Download E - Texas Optometric Association

2014 Certified
Paraoptometric SelfAssessment Course
Lynn E. Lawrence Sr.,
CPOT, ABOC, COA
Disclaimer…
 Disclaimer: This review course does not prepare you
for national examinations, what it does is review key
areas from the most national test outlines. To properly
prepare for a national examination you should allow
yourself ample time to fully review all tested areas for
the examination in which you are preparing.
This is a free presentation and all images
are from the public or approved sources
Practice Management
 Office Management
 Professional Issues
 Professional and Paraprofessional Functions
 Liability and Malpractice… do not go beyond your training
 Conduct, Confidentiality & Ethics… patient’s will grade you
 Hygiene and Infection Control
 OSHA… practice safely at all times
 Universal Precautions… are they infected?
 Government Rules and Regulations
 ANSI Standards… post them/know where they are
 State Laws… post them and know them
Office Procedures
 Records Management
 Confidentiality… why is this important?
 Who owns the chart? … the doctor/office
 HIPAA… how long must records be kept?
 Filing systems… what is the most widely used filing system?
 What is accounts payable mean? What the office owes
 When does an overdue bill become a bad debt? 90 days
Office Procedures/policies
Office Procedures Manual
 “Official rulebook of the practice”
 Used to clarify the policies of the practice
 It is a dangerous practice not to have one, or to
not know where it is
 Ensure emergency procedures are taught on a
reoccurring basis
 If your office does not have one contact me at
[email protected] for a sample copy
Office Procedures
Patient Recall
 Types of recall… what is the best method of
recall?
 Methods of Making appointments… when is
the best time to appt a pt?
1
Patient Handling
Telephone Techniques…1st contact
 Greeting… be pleasant and smile
 Taking messages… best method of messages?
 Handling requests for information
 Handling complaints
 Making appointments
 Confirming appointments… why? Impress your docs,
Patient Handling…builds the practice
Public/Professional Relations
 Types of correspondence and brochures







“Welcome to the Practice”
Referral letters
Consultation letters
School reports
Legal reports
Patient information pamphlet
InfantSee and Baby care programs
call pts during slow times
When and how do you handle a complaining patient?
Patient Handling
 Triage Categories:





Emergency-immediate…example
Urgent-12-24 hours…example
Routine-next available appointment
What to you do when you are not sure
Know your office policies
What does triage mean?
What does the acronym SOAPP stand for?
Office Finances
Book keeping and Banking
Procedures





Accounts Receivable… owed to you
Accounts Payable… what you owe
Petty Cash… for small office expenses
Deposits… should be done daily
Reconciling bank statements… ASAP
What is an example of a small office expense?
Office Finances
Presentation of fees… never apologize for fees
Collection… at time of service, before the patient
leaves the office
It is less manpower intensive to
Purpose of Coding
Abstract productivity data, drives manpower
 Manage workload data, demographics
 Financial restitution from insurance companies
 Accuracy is a must! Good business practice
 Good clinical picture for services provided by the
Optometrist
collect ASAP…
What is classified as a “New Patient”?
ICD-9 code is used to _________ a classification of disease?
2
New Patient
“A ‘New’ Patient is one who has not
received any professional service
from the physician or another
physician of the same specialty who
belongs to the same group practice,
within the past 3 years.”
A CPT code identifies a type of __________ ?
Importance of Documentation
Proper documentation and proper
coding is good business practice.
In addition to getting reimbursed
for the work you do, it can avoid
provoking unpleasant audits and
incurring large fines.
Established Patient
“An ‘Established’ Patient is one
who has received professional
services from the physician or
another physician of the same
specialty who belongs to the
same group practice within the
past 3 years.” (same tax ID)
Diagnosis codes should be used at their ________ level of specificity?
Confidentiality
 What is HIPAA?
 Health Information Portability & Accountability Act
 Minimum Necessary Principle
 Requires office to take reasonable steps to limit the use
or disclosure of, and request for, PHI to the minimum
necessary to accomplish intended purpose
What is necessary every time PHI is released?
Who enforces fraud in a practice?
Privacy Act and HIPAA
 HIPAA governs the use and disclosure of
protected health information (PHI) related to:
Privacy Act and HIPAA
 HIPAA gives individuals the right to:

Request restrictions on use or disclosure of their PHI

Read and/or obtain copies of their records

Amend their records

Physical or mental health

Know when and to whom their PHI has been disclosed

Provision of health care

Request alternate confidential communications

Lodge complaints

Payment for health care
Who owns the patient’s chart?
Whose rights are being protected?
3
Professional Issues…
Professional Issues
Hygiene and infection control
 Hand washing
 Instrument disinfection
 Contact lens disinfection
Cross-contamination
Sterilization
things to consider
 Dress Appearance
 Office Communications
 Staff Relationships
 Office Authority
 Conflict Resolution
 Certification
 Continuing Education
How often should you wash your hands?
Roger Staubach #12 Dallas Cowboys!
Why is it important to conduct yourself as a professional?
Tear Film Layers
oil
aqueous
Anatomy and Physiology
snot
What functions does each layer of the tear perform?
Healthy Tears
A complex mixture of proteins,
mucins, and electrolytes coated
by a lipid layer
Lipid Secretion: Meibomian Glands
Left:
Transillumination of
eyelid showing
meibomian glands
• Antimicrobial proteins
• Growth factors &
suppressors of inflammation
Right:
Secretion of lipid
at lid margin
• Soluble mucin helps
stabilize tear film
• Electrolytes for proper
osmolarity (295-300)
– pH slightly alkaline (7.4)
• The lipid layer restricts evaporation to 5-10% of tear flow
– Also helps lubricate
Why is a tear salty tasting?
Where does a contact lens rest?
4
Lipid Secretion: Meibomian Glands
Anatomy
What eye is this?
(WC Posey, Diseases of the Eye, 1902)
Transillumination of
meibomian glands
What function does the pupil have?
How does the lipid layer aid in contact lens wear?
(Transillumination image from Dry Eye and Ocular Surface Disorders, 2004)
The Eyelid
Eyebrows and Eyelashes
 Eyebrows
 Thickened ridge of skin with
short hairs
 7 Layers of the eyelids
1. Skin-thinnest layer
2. Subcutaneous
connective tissue
3. Striated Muscle
4. Sub-muscular connective
tissue
5. Tarsal plate or fibrous layer
6. Smooth muscle
7. Conjunctiva
(Bulbar/Palpebral)
How are Hordoleum and Chalazions treated?
Lacrimal Apparatus
 Sometimes a person cannot produce natural tears that they
might need some punctal plugs.
 Diverts perspiration
 Eyelashes
 Also protects
 Sebaceous glands at base of each
lash are called Glands of Zeis
which produce a lubricating
fluid
 Fluid can harden and clog the
gland, producing a stye or
painless chalazion. If painful
and infected it is called an
external hordeolum
Cataracts (myotonia) are caused by?
Anatomy and Physiology of the Eyeball
3 Layers
 Fibrous Layer
*Cornea
*Sclera
 Vascular Layer
*Choroid
*Ciliary body
*Iris
 Nerve Layer
*Retina
*Macula
*Optic nerve
What are the three main parts of the crystalline lens?
What is the main function of each layer?
5
Conjunctiva
Sclera
 An epithelial membrane
which covers the anterior
sclera and continues to the
back surfaces of the lids to
form a conjunctival sac
 Has blood vessels which can
burst and cause
subconjunctival hemorrhage
 Three parts
 White in color
 Primary function is protection
 Pierced posteriorly by the
optic nerve
 Acts as insertion points for
the six EOMs
 Junction between the cornea
 Bulbar
 Palpebral
 Fornix - where bulbar and
and sclera is called the
Limbus
palpebral meet
What is the total power of the eye?
Cornea
What is it called when blood vessels
grow onto the cornea?
What happens when a patient gets
a scar in the visual pathway?
 Index of refraction is 1.37
 Approximately .5mm in thickness
 Transparent Organ (no blood vessels / avascular)
 Primary function is refraction of light rays
 Refractive power approx + 45.00 D
Name the mucus producing cell?
Cornea
 Composed of 5 layers
 Epithelium…24 hr healing
 Outermost layer
 5 cell layers thick
 Heals very quickly
 Does not scar
 Bowman's membrane- layer just under the epithelium NOTE:
will scar
 Stroma – middle tissue that forms 90% of the cornea
 Descemet's membrane- thin elastic layer deep in the cornea
 Endothelium - only one cell layer thick; lines undersurface of
the cornea, where it regulates corneal water content
What is the crossover point for the nasal optic nerves?
What cranial nerve is tied to corneal sensations?
Endothelial detail with nuclei
Aqueous Humor
Confocal Scanner
Epithelial detail with nuclei
Which cells do not regenerate Epithelium
or Endothelium?
 Manufactured by ciliary body
 Characteristics:
 Clear
 Watery consistency (99%
H2O)
 Functions
 Refraction of light
 Intraocular Pressure (IOP)
 Probably nourishes
posterior surface of the
cornea and the crystalline
lens
 Flows from posterior chamber
through the pupil into the
anterior chamber
How does aqueous flow out of anterior chamber?
6
Crystalline Lens
Crystalline Lens
...approx 12-14 diopters of power
 3 things happen during accommodation:
 Pupils constrict
 Eyes converge
 Functions
 Lens gets thicker
 Refraction of light
 The crystalline lens contains a high degree of protein
 Accommodation


Focus adjustment of the
eye
Presbyopia is the loss in
accommodation

 Changes in the lens protein causes the lens to lose its transparency
which is a condition termed "cataract"
 Aphakia is the absence of a lens. It can be removed during cataract
extraction
First noticed around age 40.
Due to a loss in flexibility of
the lens
Name the three main parts of the lens?
Ciliary Body
Iris
 Most anterior portion of




How much focusing power does the lens have?
 Located near the base of
the vascular layer
Gives the eye its color, i.e.
blue eyes, brown eyes, etc.
Consists of blood vessels,
pigment and muscle tissue
Regulates light
Smaller with age
the iris and posterior to
it
 Composed of blood
vessels and muscle fibers
(ciliary muscle)
 Cilliary process produces
aqueous
What does the sphincter muscle control?
Ciliary body is attached to suspensatory ligaments called?
Nerve Layer - Retina
Vitreous Chamber
 Functions:
 Visual Receptors are Cones and Rods
 Cones
 Refraction of light
 Internal support


 Spots in vision may be

floaters in the vitreous
Produce color vision
Give improved acuity
Used in day vision = “Photopic” = normal and high levels of
illumination
 Rods…120 million


Produce black and white vision
Function in dim light = “Scotopic” = low level of illumination
 Cones and Rods… 6 million
Post vitreous detachment


How many chambers are inside the eye?
Used under mesopic vision = between scotopic and photopic
Both rods and cones are used.
The _____ is the strongest refractive media and has about ____ diopters of power.
7
The retina (Cranial Nerve II)
Pigment
epithelium
Vitreous
Which cranial nerve controls the superior oblique muscle?
Retina – 10 layers
Outside of eye
The levator palpebrae raises the eyelid and is innervated by CN #?
Identification of Retinal Layers
NFL
ILM
GCL
IPL
OPL
 Pigment epithelium
 Rods
 Cones
 Outer plexiform layer
 Horizontal cells
Stratus OCT™
 Bipolar cells
IS/OS
 Amacrine cells
RPE/CC
IS/OS: Junction of inner and outer
NFL: Nerve Fiber Layer
ILM: Inner Limiting Membrane photoreceptor segments
RPE: Retinal Pigment Epithelium
GCL: Ganglion Cell Layer
CC: Choriocapillaris
 Inner plexiform layer
Choroid
IPL: Inner Plexiform Layer
OPL: Outer Plexiform
 Ganglion cells
 Nerve fiber layer
Cross-sectional image of live tissue; a virtual biopsy
Vitreous (inside of eye)
Nerve Layer - Retina
Nerve Layer - Retina
 Optic nerve head (optic
 Ora Serrata
disc)
 No receptors -
physiological blind spot
 Point of exit of optic
nerve
 Appears yellow
compared to the orange
retina
 Land mark attachment site
for choroid and retina
 Most anterior portion of
retina
 Nearly all rods
How many layers are in the retina?
What is Pars Plana?
8
Anatomy and Physiology
of the extraocular muscles
Extra Ocular Muscles
 The Extra-ocular Muscles
(EOM)
 Organized into an umbrella-
like bundle among the orbital
fat, orbital blood vessels and
nerves
 Six muscles associated with
eye movements






Superior rectus (S.R.)
Inferior rectus (I.R.)
Medial rectus (M.R.)
Lateral rectus (L.R.)
Superior oblique (S.O.)
Inferior oblique (I.O.)
How many cranial nerves control these 6 muscles?
Extraocular Muscles
 Medial Rectus
- Most powerful, adduction,
CN III
 Inferior Rectus
- Primary is depression, CN III
 Lateral Rectus
- Abduction, CN VI
 Superior Rectus
- Primary is elevation
What is the name of the point where the muscles come together?
Muscles and Function
 LR6…SO4…3
 Rectus
 Obliques
 Intorsion
 Extorsion
 Elevation
 Depression
Which muscle close the eye lid and is innervated by cranial #7?
An obvious upward/superior deviation of the eye is called?
Extraocular Muscles
 Superior Oblique (SO)- has 3 functions; intorsion, depression and
abduction; innervated by the 4th (trochlear) cranial nerve
 Inferior Oblique (IO)- 3 functions; extorsion, elevation, and abduction;
innervated by the 3rd (oculomotor) cranial nerve
Extraocular Muscles
 Medial Rectus (MR)- moves the eye inward from the
straight-ahead position (adduction); innervated by the 3rd
(Oculomotor) cranial nerve
 Lateral Rectus (LR)- moves the outward (abduction)
from the straight-ahead position; innervated by the 6th
(Abducens) cranial nerve
 Inferior Rectus (IR)- 3 functions; depression, extorsion, and
adduction; innervated by the 3rd (Oculomoter) cranial nerve
Proper alignment and muscle balance of the eyes is called?
A definite and obvious turning of the eye is called?
9
Ocular Motility
Muscle Balance Testing
 Cover Test
 Version - a conjugate movement of the 2 eyes. Both eyes
 Cover/uncover
remain parallel during the movement
 Vergence - A disjunctive movement of the 2 eyes
 Alternating cover
 Hirschberg Test
 Convergence

 Location of corneal reflex
Near triad of accommodation, pupil constriction, and convergence
 Divergence
Which test checks for direction when using the cover test?
A constant tendency for the eyes to turn from the norm is called?
Extraocular Muscles
Extraocular Muscles
 Medial Rectus
 Toward the nose (adduction)
 Lateral Rectus
 Away from the nose (abduction)
 Superior Rectus
 Up;towards the nose (elevation)
 Inferior Rectus
 Down;away from the nose (depression)
 Superior Oblique
 Rotates the top of the eye toward the
nose;moves eye down
 Inferior Oblique
 Rotates the top of the eye away from the nose;
moves eye up
Where is the insertion points for these muscles?
How many extra ocular muscles are there?
Bony Orbit
Orbit
 Openings of the orbit
 Purpose of openings


Transmit arteries and/or veins to and from the orbit
Transmit nerves to and from the orbit
 Types of openings


Fissures (crevices/cracks)
Foramina (holes)
 Major openings


Optic foramen - II cranial nerve - Optic Nerve
Supraorbital fissure - IV cranial nerve - Trochlear Nerve
The transition zone between the sclera and the cornea is called?
1.
2.
3.
4.
5.
6.
Frontal bone…forehead
Ethmoid bone…weakest
Palatine bone…smallest
Zygomatic bone…strongest
Lacrimal bone
Maxillary bone
The conjunctiva has two divisions, they are?
10
Cranial Nerves LR6SO4
3
Muscles
 Lateral rectus muscles
#6 …abducens nerve
 Superior Oblique #4
…trochlear nerve
 All other muscles are
controlled by #3 …
oculomotor nerve
Name the 3 chambers of the internal eye?
Visual Pathway Objectives
Anatomy Physiology
 The Orbit
- Bones, etc.
 The Sinuses
- Locations
 Human Body Planes
 External Structures
- Eyelids
- Conjunctiva
- Eyelashes and Eyebrows
 Lacrimal System
The outer layer of the eyeball is called?
Visual Pathway
 Define the visual
pathway
 Identify structures in the
visual pathway
 Testing used for the
visual pathway
 Identify defects within
the visual pathway
Anisometropia occurs when there is a _____________?
Visual Pathway
 Physical
 Physiological
 Psychological
What causes your physiological blind spot?
Visual Pathway
 Visual pathway has seven
structures
 Retina
 Optic Nerve
 Optic Chiasm
 Optic Tract
 Lateral Geniculate Body (LGB)
 Optic Radiations
 Visual Cortex …where vision
occurs
Antimetropia occurs when __________ ?
Aniseikonia occurs when an object viewed by one eye is _________?
11
Optic Chiasm
Retina
 Divided into four quadrants like
the brain
 Temporal fibers do not
 Fovea at exact center
 Optic nerve head is located in
cross
 Nasal fibers do cross
nasal half
 Some fibers from the
 Each quadrant sees the exact
macula cross while
others do not
opposite visual field
What is an exudate?
What part of the brain does the vision occur?
What is papilledema?
Visual Field Defects
 Common types of field defects
 Blind spots - Areas of blindness
in the visual field
 Hemianopsia - Blindness in one
half of the visual field of one or
both eyes


Homonymous heminopia
Homonymous - Involving the
nasal half of the visual field of one
eye and the temporal half of the
visual field of the other eye
Incongruous -
Is this possible? You be the judge
Incongruous homonymous
Binasal defect
An area of blindness within a visual field is called?
Review Questions
 The point where the upper and lower eyelids meet is called
a. ora serrata
b. canthus
c. joint
d. sphinx
 The blockage of the meibomian gland is called the
Review Questions
 The eyelid will protect your eyes from…
a. blinking
b. dust particles
c. stray tears
d. a burning punctum
 What main muscles raises the eyelid?
___________ when it causes pain, and the _________ when
it does not cause pain.
 Name the five layers of the cornea in order
12
Review Questions
 The drain port for tears is called?
a. canal of Schlemm
b. punctum
c. lacrimal gland
d. zonnule of Zinn
 In what layer of the eye will chronic diseases normally manifest?
 What structure prevents a contact from going behind the globe of the
eye?
Review Questions
Review Questions
 What is the most anterior part of the retina.
 What is the total power of the Cornea, the crystalline lens
assembly, and the overall eye?
 What is the most posterior layer of the retina?
Review
 What are the layers of a tear film?
 Opia means what?
 Where is tear mucin produced?
 What is the difference between a tropia and a phoria?
 Why is the tear film important in contact lens wear?
 The optic nerve is which cranial nerve?
 Avascular means what?
 How many extra-ocular muscles are oblique?
 What function does the Canal of Schlemm have?
 What does the root word “papill” mean?
Review Questions
 Identify the name for the 3 parts of the conjunctiva
Review Questions
 _________ exist when the foveal lines of sight of the two
eyes do not point at the same object.
 A. binocularity
 In what layer of the eye will the retina be found?
 B. strabismus
 C. conjunctivitis
 D. FB sensation
 What is the strongest bone of the bony orbit?
 Of the following all are anomalies of the binocular system
except:
 What muscle of the lid would be involved in ptosis?
 A. strabismus
 B. Amblyopia
 C. anomalous correspondence
 D. conjunctivitis
13
Review Questions
 When the power of the crystalline lens correspond with
axial length of the eye, so that parallel light rays are
appropriately refracted to focus on the retina is called?




A. emmetropia
B. ammetropia
C. hyperopia
D. myopia
 An opacity of the crystalline lens is known as?




A. photophobia
B. cataract
C. edema
D. aphakia
Review Questions
 Which test checks for eye movement and helps detect the
dominate eye?
 A. muscle H
 B. cover test
 C. visual acuity
 D. myopia
 Glaucoma screening test that used puff of air onto the eye
surface:
 A. NCT
 B. snellen
 C. amsler grid
 D. accommodation
Review Questions
 Which test uses Pseudo Isochromatic Plates?




A. IOP
B. color test
C. cover/uncover
D. snellen
 This checks the power of the eye:




A. NCT
B. taking case history
C. Autorefractor
D. taking blood pressure
Review Questions
 Which test is used to check six cardinal position of gaze for
motility?
 A. Muscle H
 B. APD
 C. Amsler Grid
 D. Tropia
 Examination of the eye is performed by using a slit lamp or
another name for slit lamp is:
 A. non-contact tonometer
 B. biomicroscope
 C. pupilometer
 D. lensometer
Review Questions
 What is a good tear BUT?
 What device checks the brain-eye connection?
 What device measures the distance between the
pupils?
Ophthalmic Optics
& Dispensing
(20%)
 What device measures corneal thickness?
14
Face Framing
Prescriptions
 Square face
 Wide forehead cheek and
 Oval face
Components
chin, round and rimless
 Sphere, cylinder, axis
 Add power
 Prism
 Prism base direction
 Any style, avoid low temples
 Diamond face
 Round face
 Wide forehead to small chin,
choose small shallow ovals,
rectangles, or geometrics
 Large heads and round chins,
geometric shapes works well
Ordering
 Heart face
 Oblong face
 Wide forehead gradually
 Long narrow face with a
square chin, round or square
lens will add dimension
narrows to pointed chin,
rimless glasses work best
What is the Abbe or V-Value of a lens?
Prescriptions: Decentration
ED
Prescriptions: Vertex Power
D
BL
 Vertex distance and effective power
B
 Lenses gain minus or lose plus power as they are
 Decentration calculations
A
moved closer to the eye.
 Eye size plus distance
between lenses minus
patient’s PD divided by 2
 Example: 50-22-140 pt pd 60
 72 – 60 = 8 / 2 = 4
 Conversely lenses gain plus or lose minus as they are
moved away from the eye.
What is the speed of light in a vacuum?
This lens is said to be 50% lighter than glass?
Prescriptions: Verification
 Instruments used to Verify Rx
 Lensometer
 Lens power and axis location
 Presence, amount and direction of prism
 Geneva Lens Clock
 Base curve
 Colmascope or Polariscope
 Progressive add markings
 Calipers
 Lens thickness
Prescriptions: Snell’s Law 
 Snell’s Law of Refraction
 Light traveling from air into denser material is bent toward the normal
 Light traveling from denser material into air is bent away from the
normal
 Light striking material perpendicular to surface does NOT bend
 Normal = line perpendicular to the surface of mirror or lens
drawn at the point of contact with the light ray, angles are measured
from this line to the light ray
Frequency is the number of times the crest or trough passes _______?
A carrier and a segment describes what type of lens?
15
Prescriptions: Focal Length Calculations…
 Formula: (in meters) =
Prescriptions: Light Rays
 Rays move from left to
right
F=1/D
Focal length in meters (f ) =
1 / D (reciprocal of power in diopters)
Example: The focal length of 2.00 D lens:
f = 1 / 2.00 D f = .5 meter
Wavelength is measured from _____ to _______ of waves?
Prescription: Prism
 Prescribed when the two eyes do not align properly
 Can be induced when the optical centers of the
lenses do not line up with the patient’s PD
 Converging Rays
 Diverging Rays
The focal point forms
a real image
The focal point forms
a virtual image
Light always deviates toward the ______ of a prism?
Prescription: Prism
 Displaces light
Light bends toward base, Image displaced
toward apex
 Prentice’s Rule- used to calculate induced prism
Waves of the visual system is measured in _______ of a meter?
What is the speed of light in a vacuum?
Lenses: Convex & Concave
Ophthalmic Lenses
Properties of Light
Refraction - Prism
 Plus lenses –prisms stacked base to base
Prism bends light
towards its base...
apex
 Minus lenses – prisms stacked apex to apex
The _____ theory state that light moves as waves like those in water?
...but displaces images towards its
apex
base
16
Ophthalmic Lenses
Ophthalmic Lenses
Properties of Light
Refraction - Prism
Refraction - Prism
Minus lenses are prisms placed apex to apex...
Plus lenses are prisms placed base to base...
Light Rays
Light Rays
...resulting in divergence
...resulting in convergence
Vision & Ametropias
Vision & Ametropias
When light is not focused on the retina, an
ametropia is present... for example, a myopic
eye focuses light in front of the retina...
...a minus powered (diverging) lens shifts the
focus back to the retina
(focal length of eye + lens)
E
E
E
(unaided focal length of eye)
Vision & Ametropias
Vision & Ametropias
A hyperopic eye focuses light
behind the retina...
...a plus powered (converging) lens shifts the
focus up to the retina
(unaided focal length of eye)
E
E
E
(focal length of eye + lens)
17
Vision & Ametropias
Vision...a&cylindrical
Ametropias
lens is prescribed to
Astigmatism causes light along
different axes to focus at different
planes...
compensate for astigmatism in the eyecreating a common focal point on the retina...
E
E
E
E
(common focal lengths of eye + lens)
(multiple focal lengths in unaided eye)
Vision & Ametropias
Vision & Ametropias
...as the crystalline lens ages, it loses its
flexibility- and its ability to adjust focus...
this condition is called presbyopia and
typically becomes noticeable around age 40
E
E
E
As previously mentioned, the crystalline lens
enables the eye to focus on near objects...
E
accommodation
Lenses: Index of Refraction
 Definition: A comparison, or ratio, of the speed of
light in air to the speed of light in another medium
 Is a measure of the density of the material
 Values
 Speed of light in air in a vacuum:
 Air= 1.00
 Water= 1.33
186,000 mps
What is the wavelengths of visible light?
Lens Materials: Glass
Crown glass
Flint glass
Hi-Index glass
IR: 1.52
IR: 1.65
IR: 1.9
Advantages: More scratch resistant, clearer optics
Disadvantages: Heavier, less impact resistant
One inch is equal to _______ mm?
18
Lens Materials: Plastic
Lens Materials: Polycarbonate
CR-39
Hi-Index plastic
Polycarbonate
IR: 1.49
IR: 1.58-1.70
Advantages: Lighter weight, more impact
resistant compared to glass, easily tinted
Disadvantages: More prone to scratches, less
ultra-violet (UV) protection on untreated lens
IR: 1.54-1.60
Advantages: Lighter weight, more impact resistant
compared to plastic, naturally filters UV light.
Disadvantages: More prone to scratches, chromatic
aberration
What does a higher index of refraction mean?
The given density of any material is called __________?
Lens Materials: Trivex™
Lens Options
 Polarized
Trivex ™
 Combats reflected glare
IR: 1.53
Advantages: Lightest material available; less distortion;
as impact resistant as polycarbonite, highly resistant to
cracking around holes when used in drill mount frames;
quality optics; natural UV protection.
Disadvantages: Cannot be tinted darker than #2
The standard index of refraction in the industry is ________?
 Photochromatic
 Varies tint, works with UV
 Shatter resistant
 Trivex or polycarbonate
 Wrap-arounds
 Provides added side protection
Lenses: Coatings
 Scratch Resistant
 Anti-Reflective
 Ultra-Violet
 Mirror
Lenses: Tints
 #1- lightest
 Transmission 65-80%
(greatest light transmission)
 #2
 45-60%
 #3- darkest
 Transmission 15-40%
(least light transmission)
 Polarized…filters
glare
 Photochromatic
 Glass and plastic
Which coating is good for patients having a hard time with glare at night?
What is a great addition for fishing glasses?
19
Multifocals
Frame Types
 Basic types and styles
 Styles
 Materials
 Add and Intermediate powers
 Temple styles
 Children
 Jump (prism)…slab-off… pts
with anisometropia
What does the boxing system determine?
What part of the pupil is measured for a PAL?
Frames: Multifocal Placement
1. Grinding of the distance portion
on front of semi-finished lens
2. Semi-finished lens with modified
distance portion
3. Grinding of the Rx surface
4. Bifocal lens with slab-off prism
Ophthalmic Lenses
Lens Types – Bifocals
Flat-top bifocals are usually fit:
 to lower limbus (seg line @ lower lid)
 decentered 1.5mm in from Far PD
Bifocal Seg Height
Trifocal Seg Height
How is a progressive lens measured?
Ophthalmic Lenses
Lens Types – Bifocals
There are several types of bifocals suited to different
needs...
 Flat Tops








FT28
FT35
FT45
Smart Seg*
Curve Top (Cosmolit)
Executive (E-Line)
Round Seg (Kryptok)
Blended
Ophthalmic Lenses
Lens Types – Trifocals
Trifocal lenses have three focal lengths...
Distance
Intermediate
Near
...generally, the intermediate ADD is
50% of the near ADD
20
Frames: Parts & Verification
Dispensing -Frame Alignment
 Front- Xing
 Verification
 Eyewire size
 Bridge
 Temple length
How do you determine the frame PD?
 Coplanar
 Face form - positive and negative
 Nose pads - frontal, splay, vertical
A negative face form creates what type of fit?
Dispensing
 Fitting
 Standard
alignment
 Adjustment
 Pliers




Pad angling
Needle nose
Round-Flat jawed
Temple Angling
The tool in the picture is used for what purpose?
Changing Height or Vertex Distance
 By changing the vertex distance, you change the focal
point of the lens, changing the effective lens power
and the lens ability to focus on the retina
Common Frame Adjustment
Problems - Vertex Distance
 Increase vertex- bend both
end pieces in
 Decrease vertex- bend both
end pieces out
 Increasing vertex distance
effectively raises multi-focal
height and vise versa
Double D lens are what type of lens?
Adjustment Problem/Unequal Vertex Distance
 Unequal temple spread
 Decrease temple spread on side that is closer (In -
In)
 Increase temple spread on side that is farther from
 Move pad arms up will raise height of frame
 Move pad arms down will lower height of frame
 Lengthening pad arms will increase vertex distance
face (out - out)
 Unequal temple tension and bends behind
ears
 Shortening pad arms will decrease vertex distance
What is the average vertex distance?
A test used to determine if a patient has correctable vision?
21
Frame Adjustment - Pantoscopic Angle
 Increase panto - bend both
temples down
 Decrease panto - bend
both temples up
 Increasing panto will raise
the frame front height on
the face; however, it will
effectively lower the
multifocal and vice versa
Pre-Testing Procedures
(20%)
Another name for the swinging flashlight test is?
General Info
 Before using a piece of equipment with an adjustable
eyepiece, you MUST adjust it to your eye
 Before performing a test be sure to know what you are
testing and what is WNL
 Do not erase a medical record
Interpupillary Distance Measurement
 Distance and near
 PD measuring
ruler
 Pupillometer
 Monocular PD
measurement
1
2
3
4
5
6
7
1st measurement 60 mm
1
2
3
4
5
6
7
2nd measurement 64 mm
What is the best method of measuring a PD?
A test used to determine defects within the 20 degree of the central macula?
Pupillary Responses
Pupil Testing
Light the pupil for _____ seconds?
 Assure that the sensory pathway is
working
 Direct and consensual responses to
light
 Response to accommodation
Explain the accommodation portion of the PERRLA.
Assure that the sensory pathway is working
Direct/consensual responses to light
Response to accommodation
APD
What does an positive APD (+MG) identify?
22
Pupillary Response: Recording
Example #1
P= pupils are
E= equal
R= round
R= react to
L= light and
A= accommodation
-/+RAPD (relative
afferent pupillary
defect
Example #2:
5mm/4mm
2+ (reaction time)
R & R (round &
reactive)
-/+ RAPD (also called
Marcus Gunn pupil)
Near Point of Accommodation
 Ability of the eyes to focus at near
 Binocular measurement
 Amplitude of accommodation
 Binocular or monocular measurement
 Distance measured in cm
This is an ocular motility test that checks at least 6 cardinal positions?
AC/A ratio is usually _______ in elderly patients
Extra-Ocular Muscle Testing
Cover Test
 Versions
 Assess heterophoria and heterotropia
 conjugate movements of the eyes together
 Vergence
 disjunctive movements of the eyes
 Pursuits
 Movement of the eyes while following a moving target
 Saccades
 Two separate tests - unilateral and
alternate
 Tests are performed at distance and near
 Unilateral test is performed first
 Jumping movements from one target to another
An exotropic patient’s eye would deviate in what direction?
An orthophoric patient would have what type of eye deviation?
Unilateral Cover Test
 Determines heterophoria or heterotropia
 Heterophoria=tendency
 Heterotropia=constant
 Determines frequency (constant or
intermittent)
 Unilateral or alternating
An alternating cover test determines what?
Alternating Cover Test
 Determines the direction
and magnitude of the
tropia or phoria
 Eso-in
 Exo-out
 Hyper-up
 Hypo-down
Hyper
Exo
Eso
Hypo
A left eye that deviates upward is classified as _______ ?
23
Ocular Motility
 Muscle-H Test
 Ocular Motility
 Patient instructions
 Appropriate target
 Proper illumination
 Proper distance
 Accurate recording
Cover Test
 Cover Test
 Pt instructions
 Eye level position
 Proper fixation
 Procedures for
cover/uncover
 Recording accuracy
What does the Muscle H test check for?
What is the difference between a tropia and phoria?
Fusion/Suppression
Confrontation Fields
 Fusion
 Currently tested on practical exam
 Performed at arms length
 Screening for gross visual field defects
 Blending of 2 images, one from each eye
 Suppression
 Subconscious inhibition of an eye’s retinal image
 Associated with strabismus
 Comparison of examiners visual field (known) to
the patient’s (unknown)
What is the highest degree of fusion called?
True or False: A heminopsia can be identified performing a confrontation field?
Case History
■ Chief Complaint…critical for insurance filing!
■ Reason for visit-recorded in patient’s own
words
■ History of present illness
■ Detailed information on chief complaint
■ Medical/ocular history (Dx)
■ Family History (FHx)
■ Social history (age-appropriate)
■ Alcohol? Smoke? Occupation? Live alone?
Case History
 Tested during the CPOT practical exam
 Components
 Medical and ocular history


Patient
Family
 Occupation and avocation
 Confidentiality
HIPAA…how long are records maintained?
Which part of the case history is used with insurance filing?
24
Ocular Symptoms
Ocular History
 Rule out specific ocular problems
 Always ask how long has pt has symptoms
 Ask open ended questions
and conditions, such as:
 Itching
 Burning
 Glaucoma
 Tearing
 Cataracts
 Redness
 Keratoconus
 Irritation
 Blurred vision
Match the diseases to the structure…
 Other symptoms
What is itching usually a sign for allergies?
Define Visual Acuity
Medications
Name
 The measurement
of the ability of the
eye to see detail
Amount taken
Frequency
Prescribed for
Prescribed by
Illegal drugs too!
What does 5/400 mean on a visual acuity chart?
Why is illegal drug use important?
Procedure
 Always observe patient.
 No squinting. Why?
 When do you obtain pinhole acuity?
 Visual acuity better with one eye or two?
 Note any consistent pattern in the letters
missed by the patient. Why?
The Hardest Acuity
 What is the most




difficult acuity you have
ever taken
Were you prepared for
it?
Are children difficult?
What do you do with the
parents?
What happens when it is
taking too long?
What is the definition of acuity?
25
Procedure
 Patient unable to see
Visual Acuity: Snellen Fraction
the big “E”
 Walk up method
(15/400, 10/400, 5/400)
 Count Fingers- CF @
_____ft
 Hand Motion- HM
@______ft
 Light Location
 Light Perception
How is “no light perception” documented?
Types of Acuity Charts
 Snellen
 Metric (Bailey-Lovie)
 Low Vision Charts
 Illiterate Charts
 Landolt “C” or rings
 Tumbling “E”
 Numerator
 Represents the testing distance in feet or meters
 20/_____; 6/______
 Denominator
 Represents the distance at which the letter subtends
a 5-minute angle of arc in distance or meters. Also
referred to as the letter size.
How would you document a patient that can only see the big “E” at 10 feet?
Color Vision
Should use pt’s current Rx
Types of color vision tests
 Pseudoisochromatic plates (PIP)
 Farnsworth D-15
 Farnsworth 100 hue
 Nagel Anomaloscope
 Lighthouse charts
How do you document the PIP color test?
Which of these charts is the standard VA chart in the US?
Pseudoisochromatic Plates
(PIP’s)
Ishihara
14, 24, or 38 plates
Plate #1 can be read
by anyone, even those
with color defects
What happens if the patient can’t see this plate?
Significance
 8-10% Males
 .4% Females
 Green defect occurs most frequently
 This is strange due to the color of money 
Who passes the defected gene that causes color deficiencies?
26
Color Vision Classification
 Trichromatism
Color Vision:
Method for Testing
 Normal color vision
 Monocular vs. Binocular
 Protanope- without Prozac I see red
 Red deficiency
 Test distance 75 cm (30 inches)
 Deuteranope- The dew is on the grass
 Illumination
 Green deficiency
 Tritanope- King Titan of the ocean blue
 Macbeth daylight lamp
 Blue-yellow deficiency
 Illuminant C lamp
What disease can be ruled out with monocular testing?
Which sex (M/F) is most likely to have a color deficiency?
Stereopsis
 Highest degree of depth perception
 Purpose of test
 Types of stereo tests
 Titmus stereo fly
 Randot
Exam Equipment







Retinoscope
Ophthalmoscope
Biomicroscope (Slit lamp)
Phoropter
Keratometer
Fundus Camera
Optical Coherence Tomographer
 Reindeer
What type of glasses are used for this test?
Visual Acuity
Which one of these can be used during objective refraction?
Angle of Arc
 Types and charts
 Snellen
 Feinbloom (Low Vision)
 Pre-school and Illiterate



Allen picture cards
Tumbling E’s
HOTV
 Used to determine
the detail in a letter
 Each of these
arrows indicate one
minute of arc
When a child really wants glasses but there is no medical reason for them,
What is it called?
A person with normal color vision is called a _______ ?
27
Procedure
Procedure
 Distance w/out RX
 Near w/out RX
 Distance with RX
 Near with RX
 Or a variation of the
above
 Patient unable to see the big “E”
 Walk-up
 Count Fingers- CF @ _____ft
 Hand Motion- HM @______ft
 Light Projection (also known as light location)
 Light Perception
What happens when you fail to identify cc or sc glasses?
How many “minutes of arc” is the Big E?
Pinhole
 The pinhole test is used to confirm whether or
not refractive error is the cause of decreased
visual acuity. 20/30
Procedure





Always observe patient.
No squinting. Why?
When do you obtain pinhole acuity?
Is visual acuity better with one eye or two?
Note any consistent pattern in the letters
missed by the patient. Why?
A reduction in vision without any apparent cause is defined as?
Conversion
Cover Testing
 Cover Test
 Determines if there is a
 Feet to meters
 Multiply the denominator by .3
tropia
 Watch eye that is not being
covered
 Cover/Uncover Test
 Meters to feet
 Divide the denominator by 3
 Add a zero
 Determines if there is a
phoria
 Watch eye that is being
uncovered
 Direction of Deviation
 Eso (IN); Exo (Out); Hyper
(Up); Hypo (Down)
Inflammation of the eyelid is called ________ ?
Most floating object identified in a patient’s vision is where in the eye?
28
Cover Test
 Cover Test
Eye Movements
 Versions
 Pt instructions
 Eye level position
 Proper fixation
 Procedures for cover/uncover
 Recording accuracy
 A conjugate (together)
movement of the eyes such
that their meridians or lines
of reference move in the
same direction
 Vergence
 A disjunctive movement of
the eyes such that the points
of reference move in
opposite directions.
Ex: convergence
What direction does the eye turn during adduction?
Binocular Vision
The ability of the eyes to focus from a near target to a far target is called?
Is this a Tropia or Phoria/why?
 Fusion
 The act or process of blending, uniting or
cohering vision in both eyes
 Phoria
 The orientation of one eye in the absence of an
adequate fusion stimulus…latent, tendency of the
eye to turn
 Tropia
 Binocular fixation is not present under normal
seeing conditions…mostly obvious
What happens when you
cover this eye?
How would you document this condition?
What term is used to identify an out-turning of the eye?
Binocular Vision
 Strabismus
 Tropia-manifest deviation of the eyes.
 Phoria is a latent deviation held in check by
fusional vergence
 Frequency- constant/intermittent
AC/A Ratio
 Accommodative convergence to
accommodation
 Near point of convergence
 Units of prism diopters of convergence over
diopters of accommodation
What condition is this?
What happens when the
Right eye is covered?
 Ex: 4 /1D
Explain the relationship between AC/A and the age of a patient?
29
Pupil Testing
Eye Dominance
 Explain test
 Proper lighting
Eye preference
Eye used for monocular
viewing or sighting
Reasons for recording
Monovision CTL
 Perform direct and
consensual
 Swinging flashlight
 Evaluate near response
 Recording accuracy
Is it required to have corrected vision for pupil testing?
The rotation of the eye around an anteroposterior axis, such as fixation is called?
Pupil Testing
Pupil Testing
 Relative Afferent Pupillary Defect
 Adie’s Tonic Pupil-slow response to light
 Argyll Robertson-no reaction to light; reaction to
 Anisocoria- unequal pupil sizes
 “cor” = pupil
 “aniso”=difference
 Hippus- “jumping” pupil
 Most commonly seen in younger patients
accommodation
How long should the light be held in front on the eye during pupil testing?
Congenital color vision defect normally impact vision in ______ eyes?
Color Vision
 Types of tests
 Pseudo-isochromatic
plates (PIP)
 Farnsworth D-15/100
Hue
 Nagel Anomoloscope
Color Vision
 Procedure for PIP
 30 inches/75cm distance…very important
 Near Rx
 Monocular
 Daylight lamp/Illuminant C lighting
 Record number of plates correct over number of
plates tested (ex: 7/7; 4/7)
A test that measures the eyes ability to move toward the midline
and maintain binocularity is called _______ ?
What is the most common color defect?
30
Stereopsis
Keratometry
 Objective Refraction
 Procedure
 Types of tests
 Stereo Fly
 Focus eyepiece
 Randot
 Adjust instrument for
 Procedure
patient
 Polaroid filters
 Alignment
 Suppression check
 Patient instruction
 Recording
 Primary meridian-
180/secondary- 90
 Seconds of arc
 Take reading
 Record
How much of the central cornea is measured?
What is another name for a monochromat?
Corneal Topography
 Measurement
of the
curvature of the anterior
corneal surface.
Pachymetry
 A Pachymeter determines
thickness of the cornea by use of
ultrasound
 Refractive surgery
 Glaucoma diagnosis
What corneal disease can detected using
this instrument?
Tonometry
 Instruments
 Applanation- Goldmann…touches patient
This is the industry gold std
What medication is used
during this test?
How might IOP pressure be impacted by
The thickness of a cornea?
Tonometry-indentation
 Instruments
 Perkins Hand-held
tonometer… touches
patient
What is the rule for a difference in IOP
between the left and right eye?
31
Tonometry
 Instruments
 Tonopen…
 Touches pt
Tonometry
 Instruments
 Non-contact (“Airpuff)…does not touch patient
Significantly growing in use
What type of medication is
?used with this test
Tonometry
 Procedure
 Patient preparation
 Alignment
 Measurement
 Recording
 mmHg- millimeters of mercury
Why is non-contact tonometry so popular?
Visual Fields
 Types of Tests
 Confrontation
 Flat Field Tangent
Screen Amsler Grid
 PerimetryGoldmann Bowl
 Automated
What does squinting cause when performing tonometry?
Which of these visual field test is the industry standard?
Visual Fields
 Purpose is to determine the extent of the
physical space that is visible to an eye in a
given position
 Normal Visual Field parameters
 60 degrees superior … up
 75 degrees inferior…down
 105 degrees temporally…out
 60 degrees nasally… in
Fixation loses on the HVF identifies a patients ______ ?
Terminology
 Isopter
 Map of the circumference of a visual filed determined by
a test object of a certain size
 Physiological Blind Spot
 15 degrees temporal to fixation
 Represents the area in the retina occupied by the optic
nerve head
 Scotoma
 Area of partial (relative) or complete (absolute)
blindness within the confines of a normal visual field
A during a Humphrey’s Visual Field false negative means what?
32
Special Procedures
 Ultrasound
Terminology
 Isopter
 Map of the circumference of a visual filed determined
 A-Scan…sound waves in a straight line… axial length
 B-Scan…sound waves radiating… ultrasound
 Potential Acuity Meter (PAM)…cataracts
by a test object of a certain size
 Physiological Blind Spot
 15 degrees temporal to fixation
 Contrast Sensitivity…cataract, corneal opacity, or
other disease
 Biomicroscopy (Slit Lamp)…
 Represents the area in the retina occupied by the optic
nerve head
 Scotoma
 Surgery
 Area of partial (relative) or complete (absolute)
blindness within the confines of a normal visual field
 Specular microscope
What is the power of a lens that focuses light at 20mm?
Terminology
 Hemianopsia-1/2 of visual field
 Quadranopsia- quadrant
 Homonymous- same side
 Congruous- completely identical
What is the most posterior part of the retina?
Blood Pressure
 Please understand the
procedure
 Incongruous- not identical
 Correct position
 Explain it
 Hysterical- Tubular defect caused by patient’s
 Perform it
emotional state
 Document it
 No more than 3 attempts
The swinging flashlight test is used to detect what?
What is the speed in which you regulate the release of pressure during the
measurement
Sphygmomanometry
 Procedures
 Interpretation
 First number=systolic pressure (the amount of
force on the artery walls when the heart beats
 Second number=diastolic pressure (the amount of
force when the heart is at rest)
 Incidence of Hypertension
Readings
 Normal

The “normal” for adults is approximately 120mmHg
/between 70-80mmHg
 Abnormal

Mild Hypertension




145-159mmHg/90-104mmHg
Severe Hypertension
160mmHg or more/100mmHg or more
Hypotension

Below normal blood pressure
What disease is a sure indication for BP?
Can a technician determine if a patient has high blood pressure?
33
Abnormal Blood Pressures
 Systolic greater than 140*
 Diastolic greater than 90*
 Difference less than 30 between the Systolic and
Diastolic Pressures.*

These are general guidelines and may differ from the guidelines that the provider you are employed
by uses.
A patient is running late and rushes into the office, should the tech take a BP?
How Is The Test Performed?
 Inflate the cuff to approximately 20-30 mmHg
(millimeters of mercury) higher than the systolic
pressure
 Open the valve slowly…2-3 secs
 Record the number from the sphygmomanometer
when the pulse is first heard
 This is the systolic pressure
How Is The Test Performed?
 Wrap the blood pressure cuff around the upper
arm about 1 inch above the bend of the elbow
 Place the earpiece of the stethoscope into your
ears
 Place the head of the stethoscope over the
brachial artery
 Make sure that the valve is closed on the cuff.
What ocular motility test checks 6 cardinal positions
and is used to detect muscle abnormalities?
How Is The Test Performed?
 Continue releasing the valve
 The pulse will disappear
 Record this number
 This is the diastolic pressure
 Release the rest of the air and remove
the cuff
What measurement is stereo testing recorded in?
Does cuff size matter?
Contact Lens
Contact Lenses
 Pre-fit evaluation
 Palpebral fissure size…prevents glares issues
 Visual Iris Diameter- measure limbus to limbus
 Break up time- BUT- Tear Quality…


Good tear BUT 15-20 seconds
Minimal tear BUT 10-15 seconds
 Schirmer Tear test- Tear Quantity…
 Keratometry, Topography, Refraction
Movement of a contact lens upon blinking should be _____ mm?
34
Spectacle Rx
-5.00 –1.25 x 180
-5.00
-1.25
-6.25
(-5.75)
Fitting Theory
 On “K”- same Rx
 Flatter than “K”- Less minus; more plus
-5.00
(-4.75)
 Steeper than “K”- More minus;less plus
If there is not enough or too much movement on a contact,
what is the problem?
Vertex
adjusted
Rx -4.75
–1.00
x 180
Spectacle
RxCL-5.00
–1.25
X 180
Contact Lens Parameters
Fitting Theory
OZ+ 2SCW+2PCW = OAD
 Always consider the lacrimal tear layer, aka the
Overall Diameter (OAD)
lacrimal tear lens when fitting gas permeable lenses.
Optical Zone OZ
Secondary Curve (SC)
Peripheral Curve
(PC)
Secondary Curve
Width (SCW)
Peripheral Curve
Width (PCW)
What is a minimal tear BUT?
Ordering Procedures
Eye
OD
OS
RX
-2.75 – 1.00 x 030
-3.00 – 2.00 x 070
BC Dia
8.7 14.4
8.9 14.0
Brand
Remarks
AV Toric
Ciba Toric
What is used to check the fit of a contact lens?
TORIC
What is a prism ballast used for?
35
Safety First!
TRAUMATIC IRIDECTOMY
 Wash your hands!
 Procedure must be safe
 Explain procedure
 Explain do’s and don’ts
 Practical exams
automatic failure for
contact lens station
What is the minimal information needed to order contacts?
What is the correct term for bacteria free?
Care and Handling Techniques
 Lens Care Systems
 Clean
 Rinse
 Disinfect & Store
 Protein Removal
Why is it important to keep up with
current trends?
Progressive Evaluations
 History
 Visual Acuity
 Over-refraction
 Slit Lamp examination
True/False: Hygiene is a indicator of contact lens compliance?
Insertion and Removal Techniques
 Soft
 Patient comfort
 RGP
 More difficult
 Use gravity
What is required before handling contact lens?
Special Lens Designs
 Bifocal
 Toric
 Front
 Back
 Bitoric
 X-Chrome- color vision
 Rose K
 Orthokeratology
 CRT- Corneal Refractive Therapy
Which of the above contacts lens are used with Keratoconus?
36
Contact Lens Complications
FUSARIUM
 GPC- Giant Papillary
Bacterial
Ulcer
Conjunctivitis
 Contact Lens Induced
Papillary Conjunctivitis
 Keratitis-inflammation
of the cornea
 Abrasion- rubbing off of
the superficial layer
GPC
 Acanthoamoeba
 Pseudomonas
Which part of the conjunctiva is infected?
Vision Therapy
 Convergence Insufficiency- difficulty
Herpes
Fusarium Keratitis
What of the above is caused by a virus?
Amblyopia
 Strabismic
 Due to an eye turn
(tropia)
Which eye is the dominate eye?
turning eyes in
 Convergence Excess- Esophoria at
near/orthophoria at distance
What is another name for the high-plus lens magnifier?
Vision Therapy Equipment
 Haidinger Brushes
 Vectograms
 Polarized sterogram;
one image seen with one
eye; the other with the
other eye
 Tranaglyphs
 Trade name for redgreen targets used for
vergences and to
eliminate suppression
 Refractive
 Due to an uncorrected
refractive error
 Ex Anopsia
 Non use or prolonged
suppression
Vision Therapy
 Eccentric Fixation…present under monocular
conditions when retinal fixation is someplace
other than the fovea
 Anomalous Retinal Correspondence … using
another area other than the central macula is
being used to view an object
Tranaglyphs are used to identify what in vision therapy?
Red Cap desaturation testing is used to determine what?
37
Low Vision Aids
Low Vision
 Head Borne
Microscope
 Classification
 Legal Blindness

 Large field of view,
>20/200 BCV in the better eye or >20 degree visual field
in the best eye
 Low Vision
 Individuals can be helped significantly by vision
enhancement aids.
 Goals are the key to success
 Goals should be task oriented
hands free
 Hand Held Magnifier
 Portable
 Stand Magnifier
 Stable
Keratitis is an inflammation of this structure?
Anomalous Retinal Correspondence is ____________ ?
Low Vision Aids
 CCTV’S
 Electronic magnifier
 Telescope
 Magnify objects at
distance
 Non-Optical
 Large print books,
clocks, etc.
 Modified lighting
Review Questions
 A test used to detect the presence of a phoria or tropia is
 A. Broad-H test
 B. interpupillary distance
 C. Cover test
 D. alternation exotropia test
 The central portion of the retina surrounding the fovea,
CCTV
responsible for acute vision is called?
 A. macula
 B. choroids
 Cornea
 Ciliary muscle
When do headaches occur that come from uncorrected refractive error?
Review Questions
 The distance between the centers of the pupil of each eye is
called?
 A. pd
 B. retroscopic
 C. pantoscopic
 D. IOP
Review Questions
 One of the most important procedures in any eye
exam is ________?




A. Filing out insurance forms
B. taking a case history
C. determining the dominate eye
D. measuring pupillary distance
 Condition where the optic nerve is damaged from
increased ocular pressure is?
 A. glaucoma
 B. blepharitus
 C. chalazion
 D. psuedophakia
 Test distance for color vision testing is:




A. 16 inches
B. 20 inches
C. 25 inches
D. 30 inches
38
Review Questions
 Which term relates to an obvious deviation of an eye?
 A. ortho
 B. phoria
 C. tropia
 D. bino
 A duction is defined as the observation of movement of:
 A. one eye while the opposite eye is occluded
 B. both eyes in opposite directions
 C. both eyes the same direction
 D. one eye while the opposite is opened
Review Questions
 The highest degree of fusion is called




A. flat fusion
B. superimposition
C. stereopsis
D. simultaneous perception
 When the power of the crystalline lens correspond with
axial length of the eye, so that parallel light rays are
appropriately refracted to focus on the retina is called?




A. emmetropia
B. ammetropia
C. hyperopia
D. myopia
Review Questions
 What type of stereo test is done on a monocular
patient?
 Explain the finding of 20/40?
 Explain CVT 10/14?
 How is a +APD determined?
Ophthalmic Optics
and Dispensing
(20%)
 What is a common test given binocularly?
Ophthalmic Lenses
Properties of Light
Movement of Light
As light spreads from a point, it forms a wavefront...
Wave Theories
 Wave Theory
 Light moves like waves
from the ocean
 Corpuscular Theory
 Light as being minute
particles which originate
from a light source
20 ft light goes parallel
39
Optical Principles of Light
Reflection
 Visible wavelengths extend from 400-740
 A rebounding of light by the surface of a medium
nanometers (nm), 400nm being violet and 740nm
being red.
 Light is radiant energy
 A change of wavelength is perceived as color
change.
such that it continues to travel in that medium
but in an altered direction
IN
CID
EN
T
RA
Y
ANGLE OF INCIDENCE
NORMAL
OR
PERPENDICULAR
ocular center
ANGLE OF REFLECTION
400
500
600
700
Color vision testing is performed ________ correction at ______ inches?
Refraction
Y
RA
T
EC
FL
RE
What is a common household item that uses this concept?
Minus and Plus lens
The
altering of the pathway of light from
its original direction as a result of passing
through one refractive medium to another
with a different index of refraction
Air
Air
ED
Glass
Glass
Air
If a patient develops a disorder after 6 months of age it is termed ________?
 Minus lens produce a
virtual image
 Plus lens produce a real
image
 Corrects for myopia
 Thinner in the middle
 Corrects for hyperopia
 Diverges light rays
 Thicker in the middle
 Minifies images
 Converges light rays
 Apex to apex lens
 Magnifies images
 Produce virtual focal
 Base to base lens
points
 Cylinder power on the
backside of lens
 Produces a real focal
point
Info only slide
Visual Anomalies
Ametropias
An eye with insufficient focal power for its length focuses
light in front of the retina...
...this refractive error is known
as “hyperopia” uses a plus lens
for correction
Info only slide
Visual Anomalies
Ametropias
Another refractive error can occur if every axis is not
refracted evenly...
...this refractive error is known
as “astigmatism” uses a
compound lens for correction
Info only slide
40
 Back surface is called the
Visual Anomalies
Ametropias
As the eye ages, the crystalline lens loses flexibility...
ocular surface is close to –
6.00 diopter … minimizes
distortion
Base Curve
 Front surface is known as
the base curve
 Base curve becomes
steeper with plus lenses
and flatter with minus lens
...this results in a
condition known as
“presbyopia”
 Should be measured prior
Info only slide
Info only slide
Ophthalmic Lenses
Prism
 Has two flat surfaces which are not parallel

Properties of Light
Refraction - Prism
 Has two purposes
 Deviation

Correct curve lens
to each order
Light deviates towards the base
Image is displaced towards the apex
Prism bends light
towards its base...
apex
 Dispersion

Results in chromatic abberrations
All prisms break white light into its
component colors...
True/False: Amblyopia can impact binocularity?
Ophthalmic Lenses
Plus lenses are prisms placed base to base...
...but displaces images towards its
apex
base
Vision & Ametropias
...a plus powered (converging) lens shifts the
focus up to the retina
(unaided focal length of eye)
Light Rays
E
E
...resulting in convergence
(focal length of eye + lens)
41
Ophthalmic Lenses
Vision & Ametropias
Minus lenses are prisms placed apex to apex...
...a minus powered (diverging) lens shifts the
focus back to the retina
(focal length of eye + lens)
Light Rays
E
E
...resulting in divergence
(unaided focal length of eye)
Frame Selection
Frame Measurements
 Materials
 Styling
 The BOXING System
 A = horizontal
 B = vertical
 DBL
 ED = longest
ED
 Frame size
 Front, Bridge, Temples
D
BL
B
A
Where do you begin frame alignment? Pg 153 blue book
What is the average vertex distance?
Basic Formulas
Basic Formulas
Box Measurements
“B” Measurement
Box Measurements
Datum Line
“DBL”
“A” Measurement
“FPD”
B = 56
Datum (56/2) = 28
Seg Ht = 22
28-22 = 6 down
A = 58
DBL = 20
FPD = 78
NPD = 60
(78-60)/2 = 9 in
42
Lens Enhancements






Scratch resistant…CR39…12-24 months wear time
Anti-reflective…increase light transmission
Ultraviolet…filters UV upto 400nm…polycarb!
Mirror…reflect light striking the lens
Sports Coating…snow, sea, land
Tints: pink, yellow, gray, brown, green
- Tint #1 – 65-80 light transmission
- Tint #2 – 45-60 light transmission
- Tint #3 – 15-40 light transmission
 Photochromatic…change due to radiant energy
Dispensing
 Fitting
 Standard alignment
 Adjustment
 Pliers
 Pad angling
 Needle nose
 Round-flat jawed angling
 Can be glass or plastic (1989)
The higher the index of refraction, the _______ the lens material?
What does “DBL” stand for?
Special Prescription Considerations
 Aphakia
 High minus…myodisc
 Industrial/Occupational
 ANSI standards
 Occupational bifocals
 Other
What is a balanced lens?
T/F An Aphakic lens is a high minus lens?
Index of Refraction= n
 Speed of light in air (in a vacuum)
 186,000 miles per second
 Standard reference in the optical industry n= 1.530
 Index of Refraction (n) of materials is determined by
how much the material changes the speed of light
when it passes through
 Air- n=1.00
 Plastic- n= 1.49
 Cornea - n= 1.37
 Formula for index of refraction is ___speed of light in air________
speed of light in the material
How much lights slows down when passing through a material = index of refraction
This type of lens forms a virtual focal point?
Focal Length Calculations
D = 1/f’ Diopters = ¼ meters = 0.25D
 F= power in Diopters
 f’= focal length in meters
 The shorter the focal length the greater the power
 The greater the focal length the lesser power
Prescriptions: Prentice’s Formula
 Prentice’s Prism Formula – if the patient is
not looking through the optical center of the lens
that has power, they are looking through prism
Optical Center
This type of lens forms a real focal point?
Induced Prism
When the axial length of the eye corresponds with the power
of the crystalline lens, it is called _______
43
Prescriptions: Prentice’s Formula
 Prism = Power x Decentration in cm
 Prism = lens power (in diopters) multiplied by
d in cm (Where d = amount the patient PD varies
from the major reference point in cm)
 Apex …the image is deviated toward the apex
 Base…light deviates toward the base
Spherical Lens
 A lens with the same curvature across the surface
Toric /Cylindrical Lens
 A lens that differs in curvature across the surface
 Cylinder axis is aligned with sphere power and the
EX: -4.00(power) x .5cm (decentration in cm) = 2 prism
diopters
total cylinder power is 90 degrees away
Sphero-cylindrical lens: are also called compound
lens
The higher the power, the more critical the measurement
A person with a esotropic eye requires base _____ prism?
“Blephar” is a root word meaning _______ ?
Multifocals
Progressive Add Lenses (PAL)
 A lens that has more than one focus distance
 Fused multifocals
 One-piece multifocals
Distance zone
Carrier lens
Minimizes image jump
Transition zone
Near zone
Larger lines means more image jump
7mm
17mm
No vision zone
28mm
Segment or add power
“Kerat” is a root word meaning ___________ ?
The area is which a patient can see on a PAL is called _____ _______ ?
Terminology
Optical Cross
 Diagram that denotes the dioptric power in the
two principal meridians of a lens
 Front surface power + back surface power equals
the power of the lens
 The purpose of the optical cross is to understand
the concept of the lensometer, transposition and
the make up of the lens
 Diopter … the measure of lens power or amount of surface curvature
 The steeper the curve the greater the power/the flatter the curve the lesser the
power
 Optical Center … no deviation of light and no prism
 Datum line = half of the “B” measurement
 Equivalent power …Add half of the cylinder to the sphere power
 Refractive power …Power of the lens
 Effective power… Back vertex power
 Vertex distance
 Distance along the line of sight from the back surface of the lens to the
cornea
What two parts of an Rx denotes astigmatism?
What type of lens has the same power is all axis?
44
Power Cross…
Optical Cross… Cartesian coordinate systems
front and back surface measurements
Base Curve
+6.00
-7.50
-7.00
+6.00
Front
- 1.00
- 1.25
 Use algebra (those in the same axis) to determine total lens power
 Rx is -1.00 – 0.50 x 180 on a +6.00 base curve
Optical Cross minus cylinder (1 min)
- 2.50
1
090
+ 3.25
+ 1.75
110
2
030
+3.25
4
035
- 1.25
+ 2.50
Optical Cross minus cylinder
090
- 2.50
-1.25 -1.25 X 090
025
-1.75
120
125
110
115
-4.25
- 2.50
3
2
090
+ 1.75
+ 2.50
030
4
- 2.75
020
- 1.25
180
025
1
- 2.50
090
-2.50 + 1.25 X 180
+3.25
4
035
- 2.75
+3.25 -1.50 X 020
+3.25
030
115
3
025
-2.75 -1.50 X 115
-1.75
5
125
035
+3.25 – 5.00 X 125
+ 3.25
+ 1.75
110
2
-4.25
115
 3
020
- 2.75
025
-4.25 + 1.50 X 025
+1.75 + 1.50 X 110
030
+3.25
-1.75
-1.75
5
- 1.25
020
-4.25
Optical Cross plus cylinder
120
120
2
+2.50 – 3.75 X 030
180
1
+ 1.75
110
- 1.25
+ 2.50
Optical Cross plus cylinder (1 min)
- 1.25
+ 3.25
4
5
If you don’t get all of these correct, please see me after class
+ 3.25
180
1
3
020
031
To take an RX off the Optical Cross in Minus Cylinder Form:
Start with the most plus sphere power (use your number line)
Your axis is “married” to your sphere
Your cylinder is the distance traveled between the sphere and number 90
degrees away (same as using the power wheel on the lensometer)
- 1.25
115
-4.25
- 2.75
120
121
090




 Measure back surface in horizontal and vertical directions
180
+1.50
090
 Measure front surface in the horizontal and vertical directions
- 1.25
180
Total lens power
Back
090
090
- 2.50
- 4.50
-1.50
+ 2.50
125
- 1.25
-1.25 + 3.75 X 120
035
5
125
-1.75 + 5.00 X 035
45
Prescriptions: Optical Cross
Optical cross is a diagram that denotes
the dioptric power in the two principal
meridians of a lens.
One meridian is the sphere power
One meridian is the cylinder power
Hint: Think of the value of the numbers as they are read
off of the lensometer wheel.
Optical Cross Steps
 Step 1 draw a number line - ------------------------------- +
3 2 1
0 1
2 3
 Step 2 read the question (plus or minus cylinder)
 Start in the direction of the less power…document it
 Document the axis of this power
 Calculate the distance traveled from set number to
termination…this is the cylinder power is the lens
What ocular condition does a patient wearing – 4.00 DS lens have?
What type of contact lens is used to correct for astimatism?
Prescriptions: Optical Cross
 Optical Cross Example
Prescriptions: Transposition
 Transposition
 Step 1 = Combine the sphere and cylinder power
+ 3.00
Plus cylinder notation:
+3.00 +2.00 x 090
180
+ 5.00
Minus cylinder notation:
+5.00 -2.00 x 180
090
Hint: The sphere is “married” to the axis; the cylinder
is the distance between the numbers on the cross
mathematically
 Step 2 = Change the sign of the cylinder
 Step 3 = Change the axis by 90 degrees
Hint: When combining positive and negative numbers,
think in terms of money. Example: -2.00 combined with
+0.50 If you are $2.00 “in the hole” and you deposit
$0.50, what is your balance?
Answer: $1.50 “in the hole”, or -1.50.
Prescriptions: Transposition (1 min)
Prescriptions: Transposition
 -1.00 +2.00 X 160
=
 -1.00 +2.00 X 160
=
 +1.00 -2.00 x 070
 +1.25 -0.75 x 030
=
 +1.25 -0.75 x 030
=
 +0.50 +0.75 x 120
 Plano +1.00 x 090
=
 Plano +1.00 x 090
=
 +1.00 -1.00 x 180
Transposition Examples
Transposition Examples
46
Optical Cross
Optical Cross
- 2.50
- 4.50
- 1.25
+1.50
121
090
031
180
- 2.50
- 4.50
- 1.25
+1.50
121
090
031
180
 To take an RX off the Optical Cross in Minus Cylinder Form:
 To take an RX off the Optical Cross in Minus Cylinder Form:
 Step 1 Start with the most plus sphere power (use your number line)
 Step 1 Start with the most plus sphere power (use your number line)
 Step 2 Your axis is “married” to your sphere
 Step 2 Your axis is “married” to your sphere
 Step 3 Your cylinder is the distance traveled between the
 Step 3 Your cylinder is the distance traveled between the
sphere and number 90 degrees away
sphere and number 90 degrees away
L -1.25 – 3.25 X 090
R +1.50 – 4.00 X 121
Find the answers to the above equations, you 1 minute
Find the answers to the above equations
Transposition
Transposition 1 Minute Drill
 Step 1 = Combine the sphere and cylinder power
 Step 1 = Combine the sphere and cylinder power
mathematically
 Step 2 = Change the sign of the cylinder
 Step 3 = Change the axis by 90 degrees
 EX: +2.00+1.00x080
+3.00-1.00x170
The purpose of transposition is to change the
same prescription into a different form
Transposition 1 Minute Drill
 Step 1 = Combine the sphere and cylinder power
mathematically
 Step 2 = Change the sign of the cylinder
 Step 3 = Change the axis by 90 degrees
 1. + 1.75 – 0.75 X 030
 2. – 2.25 + 1.00 X 170
 3. – 1.75 + 2.00 X 125
a. + 1.00 + 0.75 X 120
a. – 1.25 – 1.00 X 080
a. + 0.25 – 2.00 X 035
mathematically
 Step 2 = Change the sign of the cylinder
 Step 3 = Change the axis by 90 degrees
 1. + 1.75 – 0.75 X 030
 2. – 2.25 + 1.00 X 170 
 3. – 1.75 + 2.00 X 125 
Spherical Equivalent
-Step 1
Take half the cylinder and add algebraically to
sphere
- Step 2
Drop the cylinder and axis and write sphere only
EX. -2.00 -0.50 X 145
(half the cylinder) -0.25
(add to sphere) 0.25 + 2.00
Answer:
-2.25 Sph
47
Spherical Equivalent 1 Minute drill
Spherical Equivalent 1 Minute drill
-Step 1
Take half the cylinder and add algebraically to
sphere
- Step 2
Drop the cylinder and axis and write sphere only
-Step 1
Take half the cylinder and add algebraically to
sphere
- Step 2
Drop the cylinder and axis and write sphere only
1. – 2.25 – 1.00 X 120
2. + 1.00 – 2.00 X 090
3. + 0.75 – 1.50 X 150 
1. – 2.25 – 1.00 X 120
2. + 1.00 – 2.00 X 090 
3. + 0.75 – 1.50 X 150 
a. – 1.75 Sph
b. Plano
c. Plano (no glasses)
Prescriptions: Decentration
Decentration 1 minute drill
 Decentration calculations
 Decentration calculations
 Eye size plus distance between lenses minus
patient’s PD divided by 2.
 Eye size plus distance between lenses minus
patient’s PD divided by 2.
 Example: 52-20-145 pt PD 62
 1. 48 – 22 – 145
 52+ 20 – 62 = 10 / 2 = 5
 2. 52 – 22 – 145
pt/pd 64
pt/pd 66
 3. 58 – 20 – 140 pt/pd 67
Remember the measurements are in mm
Decentration 1 minute drill
 Decentration calculations
 Eye size plus distance between lenses minus
patient’s PD divided by 2.
 1. 48 – 22 – 145
pt/pd 64
pt/pd 66
 3. 58 – 20 – 140 pt/pd 67
 2. 52 – 22 – 145
Remember the measurements are in mm
Prescriptions: Prentice’s Formula
 Prentice’s Prism Formula – if the patient
is not looking through the optical center of the
lens that has power, they are looking through
prism
a. 3mm
a. 3.5mm
a. 6.6mm
Remember the measurements are in mm
Optical Center
Induced Prism
48
Prentice’s Formula
Prentice’s 1 minute drill
 Prentice’s rule
 Prentice’s rule
(Please check mm)
D X d (mm)
= ________
10
= prism in diopters
D= lens power in diopters
d = decentration
D X d (mm)
= ________
10
(Please check mm)
1. How many prism diopters are in: 2.5 diopters and 4mm
2. How many prism diopters are in: 3 diopters and 6mm
3. How many prism diopters are in: 5 diopters and 5mm
= prism in diopters
D= lens power in diopters
d = decentration
Prentice’s 1 minute drill
 Prentice’s rule
= prism in diopters
D= lens power in diopters
d = decentration
D X d (mm)
= ________
10
(Please check mm)
1. How many prism diopters are in: 2.5 diopters and 4mm a. 1
2. How many prism diopters are in: 3 diopters and 6mm
a. 1.8
3. How many prism diopters are in: 5 diopters and 5mm
a. 2.5
Prescriptions: Focal Length Calculations
 Formula: f (in meters) =
1/D
Focal length in meters (f) =
1 / D (reciprocal of power in diopters)
Example: The focal length of 2.00 D lens:
f = 1 / 2.00 D f = .5 meter
Focal Length Calculations
Focal Length Calculations
F = 1/f’
F = 1/f’
(meters)
F= power in Diopters
f’= focal length in meters
Example: F = 1/20(m) = .5 diopters
(meters)
F= power in Diopters
f’= focal length in meters
1. what is the power of a lens with a 20cm focal length?
2. what is the power of a lens with a 40 cm focal length?
3. what is the power of a lens with a .8m focal length?
Make sure you read the questions carefully?
Make sure you read the questions carefully?
49
Focal Length 1 Minute drill
F = 1/f’
(meters)
1. what is the power of a lens with a 20cm focal length?
1.
5 diopters
2. what is the power of a lens with a 40 cm focal length?
1.
2.5 diopters
3. what is the power of a lens with a .8m focal length?
1.
1.25 diopters
Reading Prescription
-Take the “add” portion of the prescription and
algebraically combine it to the sphere of the
Rx
-Keep the cylinder and axis the same
Ex.
-3.00 -1.00 x 090
-2.00 -0.75 X 180
Add power +2.25
Reading Rx:
-0.75 -1.00 X 090
+0.25 -0.75 x 180
Make sure you read the questions carefully?
Vertex Distance
 A distometer is used to determine the vertex
distance, which is the distance from the anterior
cornea to the back of the lens.
 More plus power is required as a lens comes closer
to the retina.
Conversion
 Feet to meters
 Multiply the denominator by .3
 Meters to feet
 Divide the denominator by 3
 Add a zero
One meter = 39.6 inches … or use 40 inches … one inch is equal to 025 meters
Optometric Math
 MULTIPLICATION AND DIVISION OF LIKE AND UNLIKE SIGNS
 When Multiplying or dividing two numbers with like signs i.e., both
plus (+) or both (-) the answer will always be a plus (+) sign. This
means that if you multiply or divide two plus (+) numbers you will get a
plus (+) answer and if you multiply or divide two minus numbers you
will get a plus (+) answer
Optometric Math
 MULTIPLICATION AND DIVISION OF
DECIMALS
A decimal number is just a whole number and a fraction
written together in decimal form. Any multiplication or
division by 10, 100, 1000, etc. simply moves the decimal
place to the left or right. For example, multiplying a
decimal by 10 would move the decimal point 1 place to the
right
7.75 x 10 = 77.5
50
Optometric Math
Optometric Math
 MULTIPLICATION OF DECIMALS. Decimals are multiplied
exactly like whole numbers and then the decimal point is added. For
example, you would multiply 25 x 25 in this way:
 DIVISION OF DECIMALS. Divisions may be written in the form
 a=c
c
 b
or a/b = c or b/a where "a" is the DIVIDEND, "b" is the
DIVISOR, and "c" is the QUOTIENT. As with multiplication, you
divide decimals exactly like you do whole numbers and then you find
the decimal place. For example: dividing 126 by 6 gives 21 as an
answer.
Optometric Math
 METRIC SYSTEM
 The metric system is based on decimals. Changing from one unit to
another requires only the movement of the decimal place. The table
below shows the meter, which is the standard unit of length, and the
parts of a meter that we will be concerned with in Optometry. It also
shows the standard abbreviations and the number of units in a meter.

1 meter (m)
= 1 meter






decimal is relatively easy. Note in the table above that
there is a difference of 2 zeros between centimeters and
meters, 3 zeros between millimeters and meters, and 1 zero
between millimeters and centimeters. This means that
when converting between:
 If you need a length, in inches, converted to
centimeters or millimeters, first convert the inches to
meters (divide by 40) then convert to the desired unit
by moving the decimal place. Conversely, if you wish
to convert from cm or mm to inches, then first convert
to meters by moving the decimal and multiply by 40 to
convert the meters to inches.
a. Meters and centimeters move the decimal 2 places.
b. Meters and millimeters move the decimal 3 places.
place
Optometric Math
 Deciding on which direction (right or left) to move the decimal
100 centimeters (cm) = 1 meter
1000 millimeters (mm) = 1 meter
Converting inches into meters
 Dealing with the problem of how many places to move the
c. Centimeters and millimeters move the decimal 1
10 decimeters (dm) = 1 meter
requires thinking about whether you should have more or less of the
unit that you desire. For example, if you are given a length in meters
and require the length in centimeters, then you must have more
centimeters than you had meters because each centimeter is smaller
than each meter. This means that you would move the decimal 2
places TO THE RIGHT. Conversely if you were converting from
centimeters to meters, you have to move the decimal place to the left 2
places. A meter is much larger unit of length than a centimeter, thus
you would have to have fewer meters than you had centimeters. All of
the possible metric conversions you will have to make are listed on the
next page: Memorize them; if necessary
Optometric Math
 When Converting


m to cm


cm to mm


m to mm


mm to m


mm to cm


cm to m
Move Decimal
2 places right
1 place right
3 places right
3 places left
1 place left
2 places left

51
Optometric Math 1 Min drill
 Convert the unit of length on the left to the units requested on the right.
1. 42 m
_____cm
_____m
2. 500 mm
_____cm
3. 80 in
_____mm
_____in
Convert to SVN or Near Rx only
 + 1.25 – 0.75 X 125
 + 1.75 – 1.00 X 090
 Add 1.50
New Rx +2.75 -0.75 X 125
+3.25 – 1.00 X 090
 - 1.50 – 1.50 X 035
 - 0.75 – 1.00 X 150
 Add 2.00

1. 42 m
3. 80 in
5. 200 mm

 Convert the unit of length on the left to the units requested on the right.
2. 500 mm
4. 0.025 cm

Optometric Math
 Step 1
 Add the add power to
the sphere power and
write it as the new
sphere power
 Step 2
 Write the new complete
Rx Sph, Cyl, and Axis
4200 cm
4. 0.025 cm
5. 200 mm
.5m
200cm
.0025 mm
8in
Convert to SVN or Near Rx only 1 min drill
 + 3.25 – 0.75 X 125
 + 1.75 – 1.00 X 090
 Add 2.50
 - 4.50 – 1.50 X 035
 - 1.75 – 1.00 X 150
 Add 2.00
 Step 1
 Add the add power to
the sphere power and
write it as the new
sphere power
 Step 2
 Write the new complete
Rx Sph, Cyl, and Axis
New Rx +0.50 -1.50 X 035

+1.25 – 1.00 X 150
Convert to SVN or Near Rx only
Math Formulas Cont…
 + 3.25 – 0.75 X 125
 Step 1
 Add the add power to
the sphere power and
write it as the new
sphere power
 Prentiss Rule
 Step 2
 Write the new complete
Rx Sph, Cyl, and Axis
 Transpose plus/minus cylinder
 + 1.75 – 1.00 X 090
 Add 2.50

New Rx +5.75 -0.75 X 125

+4.25 – 1.00 X 090
 - 4.50 – 1.50 X 035
 - 1.75 – 1.00 X 150
 Add 2.00

 Convert focal length to Diopters
 Convert diopters length to focal
 Convert to Near Rx
 Calculate the optical cross
 Calculate decentration
New Rx -2.50 -1.50 X 035

+0.25 – 1.00 X 150
52
Review Questions 3 minutes
 -1.00 -1.00 x 090 transpose
Answer______________
 - 0.50 -2.00 x 008 transpose
Answer______________
 -1.00 -1.50 x 160 transpose
Answer______________
 - 5.00 -3.00 x 088 transpose
Review Questions
 -1.00 -1.00 x 090 transpose
Answer -2.00 + 1.00 X 180
 - 2.50 + 1.50 x 103 transpose
Answer______________
Answer -2.50 + 2.00 X 098
 -1.00 + 0.50 x 162 transpose
Answer______________
Answer -2.50 + 1.50 X 070
Answer______________
Answer - 0.50 – 0.50 X 072
 + 2.50 + 2.50 x 103 transpose
Answer pl – 2.50 X013
Answer – 8.00 + 3.00 X 178
 -2.50 + 1.00 x 029 transpose
Answer______________
Review Questions 1 minute drill
 Put the following Rx on the Optical Cross
-2.00 -1.00 x 080
 -1.00 + 0.50 x 162 transpose
 - 5.00 -3.00 x 088 transpose
Answer______________
 -3.00 -1.50 x 095 transpose
Answer – 1.00 – 1.50 X 013
 -1.00 -1.50 x 160 transpose
 + 2.50 + 2.50 x 103 transpose
Answer______________
 - 2.50 + 1.50 x 103 transpose
 - 0.50 -2.00 x 008 transpose
 -3.00 -1.50 x 095 transpose
 -2.50 + 1.00 x 029 transpose
Answer – 1.50 – 1.00 X 119
Answer – 4.50 + 1.50 005
Review Questions
 Put the following Rx on the Optical Cross
-3.00 – 2.50 x 107
-2.00 -1.00 x 080
-3.00 – 2.50 x 107
-3.00
090
-2.00
080
-5.50
-300
Review Questions 90 Seconds

Give the spherical equivalent to the following prescripts
-2.00 -1.00 x 080
-1.00 -2.00 x 010
+2.00 -1.00 x030
-3.00 – 0.50 x 070
+3.00- 1.00 x 060
Answer ____________________
Answer ____________________
Answer ____________________
Answer ____________________
Answer ____________________
017
107
Review Questions

Give the spherical equivalent to the following prescripts
-2.00 -1.00 x 080
-1.00 -2.00 x 010
+2.00 -1.00 x030
-3.00 – 0.50 x 070
+3.00- 1.00 x 060
Answer -2.50 Sph
Answer –1.50 Sph
Answer +1.50 Sph
Answer –3.25 Sph
Answer +2.50 Sph
53
Review Questions

Convert the following Rx to Near Vision Only aka
NVO, SVN, reading glasses











-2.00 -1.00 x 080
-1.50 -2.00 x 180
+3.00 OU
Answer ________________
________________
-1.00 – 0.50 x 010
-2.00 -0.75 x 100
+1.25 OU
Answer________________
________________










-4.00 -0.25 x 090
-1.00 -0.50 x 098
+2.00 OU
Answer ________________
________________
+2.50 -1.00 x 090
+1.00 -0.75 x 180
+2.25 OU
Answer ________________
________________
Review Questions 1 minute drill
 Transpose the following Rx from plus cylinder form to minus
Review Questions

Convert the following Rx to Near Vision Only aka
NVO, SVN, reading glasses











-2.00 -1.00 x 080
-1.50 -2.00 x 180
+3.00 OU
Answer + 1.00 -1.00 X 080
+ 1.50 -2.00 X 180
-1.00 – 0.50 x 010
-2.00 -0.75 x 100
+1.25 OU
Answer +0.25 -0.50 X 010
-0.75 -0.75 X 100





-2.00 +1.00 x 090
Answer ______________
-1.00 +3.00 x 070
Answer ______________
-1.00 +1.50 x 010
Answer______________
- 0.50 +2.00 x 145
Answer______________
-3.00 +2.00 x 095
Answer______________
Review Questions 1 minute drill
 Convert the following prescription from minus cylinder to plus cylinder
format
 -1.00 -1.00 x 090
Answer______________
 - 0.50 -2.00 x 008
Answer______________
-1.00 -1.50 x 160
Answer______________
 - 5.00 -3.00 x 088
Answer______________
-3.00 -1.50 x 095
 Answer______________
-4.00 -0.25 x 090
-1.00 -0.50 x 098
+2.00 OU
Answer -2.00 -0.25 x 090
+1.00 -0.50 x 098
+2.50 -1.00 x 090
+1.00 -0.75 x 180
+2.25 OU
Answer +4.75 – 1.00 x 090
+3.25 – 0.75 x 180
Review Questions
 Transpose the following Rx from plus cylinder form to minus
cylinder form















cylinder form










-2.00 +1.00 x 090
Answer – 1.00 – 1.00 x 180
-1.00 +3.00 x 070
Answer + 2.00 – 3.00 X 160
-1.00 +1.50 x 010
Answer + 0.50 – 1.50 x 100
- 0.50 +2.00 x 145
Answer + 1.50 – 2.00 x 055
-3.00 +2.00 x 095
Answer -1.00 – 2.00 x 005
Review Questions
 Convert the following prescription from minus cylinder to plus cylinder
format
 -1.00 -1.00 x 090
Answer – 2.00 + 1.00 x 180
 - 0.50 -2.00 x 008
Answer – 2.50 + 2.00 x 098
-1.00 -1.50 x 160
Answer - 2.50 + 1.50 x 070
 - 5.00 -3.00 x 088
Answer – 8.00 + 3.00 x 178
-3.00 -1.50 x 095
 Answer – 4.50 + 1.50 x 005
54
Prescriptions: Optical Cross
Optical cross is a diagram that
denotes the dioptric power in the
two principal meridians of a lens.
Optical Cross Steps
 Step 1 draw a number line -
----------------------3 2 1 0 1 2 3
+
 Step 2 read the question (plus or minus cylinder)
 Start in the direction of the less power…document it
 Document the axis of this power
Hint: Think of the value of the numbers as they are read
off of the lensmeter wheel.
Prescriptions: Transposition
 Transposition
 Calculate the distance traveled from set number to
termination
Prescriptions: Transposition
 -1.00 +2.00 X 160
 +1.00 -2.00 x 070
 +1.25 -0.75 x 030
 +0.50 +0.75 x 120
 Plano +1.00 x 090
 +1.00 -1.00 x 180
 Step 1 = Combine the sphere and cylinder power
mathematically
 Step 2 = Change the sign of the cylinder
 Step 3 = Change the axis by 90 degrees
Hint: When combining positive and negative numbers,
think in terms of money. Example: -2.00 combined with
+0.50 If you are $2.00 “in the hole” and you deposit
$0.50, what is your balance?
Transposition Examples
Answer: $1.50 “in the hole”, or -1.50.
Optical Cross
Transposition
- 2.50
- 4.50
- 1.25
+1.50
121
090
180
mathematically
031
 To take an RX off the Optical Cross in Minus Cylinder Form:
 Start with the most plus sphere power (use your number line)
 Your axis is “married” to your sphere
 Your cylinder is the distance traveled between the sphere and
number 90 degrees away
 Step 1 = Combine the sphere and cylinder power
 Step 2 = Change the sign of the cylinder
 Step 3 = Change the axis by 90 degrees
 EX: +2.00+1.00x080
+3.00-1.00x170
The purpose of transposition is to change the
same prescription into a different form
55
Spherical Equivalent
Prentice’s Formula
-Half the cylinder and add algebraically to
sphere
-Drop the cylinder and axis and write sphere
only
 Prentice’s rule
EX. -2.00 -0.50 X 145
(half the cylinder) -0.25
(add to sphere) 0.25 + 2.00
Answer:
-2.25 Sph
D X d (mm)
= ________
10
= prism in diopters
D= lens power in diopters
d = decentration
Prescriptions: Decentration
 Decentration calculations
 Eye size plus distance between lenses minus
patient’s PD divided by 2.
 Example: 52-20-145 pt PD 62
 52+ 20 – 62 = 10 / 2 = 5
Refractive Status of the Eye
and Binocularity
(12%)
Common Ocular Diseases
 Amblyopia
 Ametropia
 Anisometropia
 Aphakia
 ARMD
 Astigmatism
 Blepharitis
 Cataracts
 Chalazion
 Conjunctivitis
 Diabetic Retinopathy
 Emmetropia
 Floaters
Emmetropia
 Glaucoma
 Hyperopia
 Hordeolum
 Keratoconus
 Myopia
 Pinguecula
 The refractive condition
where parallel light rays
focus on the retina when
the eye is at rest
 The image of an object at
2,000 yards focuses
directly on the fovea
 Psuedophakia
 Ptygerium
 Retinal Detachments
 Subconjunctival Hemorrhage
What is the medical term when an “other than normal” ocular condition exist?
56
Hyperopia
 A refractive condition
where parallel light rays
focus behind the retina
when the eye is at rest
 Termed farsightedness
 Patient may have 20/20
vision at distance and
near
What type of lens is used to correct hyperopia?
Astigmatism
Myopia
 A refractive condition
where parallel light rays
focus in front of the retina
when the eye is at rest
 Termed nearsightedness
 Patient may have 20/20
vision at near, but distance
vision will be reduced
Myopia is corrected with what type of lens?
Astigmatism
 A refractive condition where
different meridians of the eye
have different powers
 Corrected by lenses which
incorporate cylinder power
 Usually due to different
curvatures of the cornea
TRUE/FALSE: A cylindrical lens correct for astigmatism?
What type of astigmatism cannot be corrected with lens?
Seeing is:
 VISION… ability to see detail
 SIGHT… ability to see
 ACCOMMODATION…ability to see from far to near
 FACILITY… ability to move your eyes around and still see
TRUE/FALSE: A 60 y/o has a high AC/A ratio?
Astigmatism
 Simple- one ray is focused on the retina; the other
is focused either in front of (myopic) or behind
(hyperopic)
 Compound- both rays are focused in front of
(myopic) or behind (hyperopic)
 Mixed- one ray is focused in front (myopic) and
one ray is focused behind (hyperopic)
 Irregular is caused by a defect in the visual
pathway
A lost of accommodation around the age 40 describes __________ ?
57
Presbyopia
 Reduction in the ability
to accommodate
 Occurs normally with
age
 Reduction in lens
elasticity
Refractive vs. Axial
 Refractive causes of myopia, hyperopia and
astigmatism refer to the fact that the “error” lies
within the shape of the cornea and/or the lens
 Axial causes refer to the length of the eyeball
itself being the cause of the “error”
 Reduction in strength of
the ciliary muscle
The average axial length of an eyeball is _________ ?
Using the Worth 4-Dot test, if only two or three lights are seen ______ is indicated?
Amblyopia
Components of an Optical Prescription
 Prism
 A condition in which reduced visual acuity with no
 Prism is used to correct blurry or double
apparent cause and not correctable by refractive
means
 Often referred to as “lazy Eye”
 It is generally treatable even after age eight
 Scientists are exploring whether treatment for
amblyopia in older children and adults can improve
vision
vision due to deviated eyes
Label the conditions in each of these pictures
What is the clinical definition of amblyopia?
A
Anisometropia
 Condition of unequal refractive state of the two eyes
 An-not: iso-same: metric-measure
 A child may learn to alternate his or her vision, that is, to use one
eye for distance and one eye for near
 Being treated today by the use of contact lenses
 If the difference in the refractive error of the two eyes is slight,
binocular vision is easily attained
B
Aniseikonia
Difference
in the size of the two retinal images,
Inherent
aniseikonia caused by the refractive
condition of the two eyes
Acquired aniseikonia occurs as a result of the
effects of corrective lenses

Both
are related to anisometropia
What part of a Rx is used to correct for 15 diopters of strabismus?
What is the condition characterize by unequal refractive status between eyes?
58
Amblyopia
Pinhole Effect
 Reduced Visual Acuity
 Eliminates peripheral light rays which increases the
depth of focus
 Hides the patient’s myopia or hyperopia and enhances
their central visual acuity
 Similar to squinting
 No Apparent Cause
 Not Correctable With Refractive Means
 Strabismic- Amblyopia Ex Anopsia
 Abnormal binocularity, resulting in
suppression of one eye
 Refractive
 Uncorrected refractive error that remains
uncorrected for a significant period of time
When is the pinhole test used?
Arteries carry blood ____ the heart and veins carry blood ____ the heart?
Glaucoma
Cataracts
 Increased intraocular pressure
 Increased cupping (cup to disc ratio)
 Decrease in peripheral vision
What is a cataract?
What is the clinical definition of glaucoma?
Corneal Problems
 Foreign Body
Retinal Problems
Foreign Body
with Rust Ring
 Abrasions
 Dystrophy
 Keratoconus
 Ulcer
Corneal Ulcer
Confrontation visual field testing compares
the _____ visual field with the ______ visual field?
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Diabetic Retinopathy
Retinal Tears/Detachment
Retinitis Pigmentosa
Macular Degeneration
Hypertensive Retinopathy
Occlusions
Cytomegalovirus
Toxoplasmosis
Histoplasmosis
Normal Retina
A hyperoptic ocular deviation has the eye turning ______?
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Diabetes
Conjunctivitis
 Fluctuations with vision
 Bleeding in retina
 The “infamous” pink-eye
 Numerous causes:
 Bacteria
 Viruses
 Allergies
 Toxic Reactions (chemicals)
 Often difficult to diagnose exact etiology
 Exudates
What is the most accurate measure of intraocular pressure?
The white spot in this photo come from ________ deposits?
What do you think?
Ocular Emergencies/Disease
 What is an Eye

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Emergency
Comfort Zone
Time
Organic Matter
Testing
 Internal Disease
 External Disease
1
 Testing
 Time
4
 Asepsis Techniques
2
 Referral Process
Where are office emergency procedure written?
3
What do you think?
What is wrong in these photos?
RPE
Herpetic Dendrite
Large C/D ratio
Extreme Blood Pressure/ retinal bleeding
Papilledma
Torturous vessels
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The External Eye
Dry Eye
 Keratitis sicca
 Can be associated with systemic inflammatory
disorders, such as arthritis and lupus

Sjogren’s Syndrome
 Treatment options
 Eye Drops (artificial tears, cyclosporine)
 Punctal Plugs
 Cautery of punctae
Sub-marginal Ulcer
Thorns from plants
Visual Cortex
Use of this over the counter medication can cause dry eyes?
Visual Field Defects
 Located in the occipital lobe of the brain
 Broadmann's areas 17, 18, and 19
 A small segment of the cortex corresponds to each
minute area of the retina
 Visual interpretation
 Radiations carry visual
impulses from the LGB
What is an absolute scotoma?
 Common types of field defects
 Blind spots - Areas of blindness in the visual field
 Hemianopsia - Blindness in one half of the visual field of
one or both eyes

Homonymous - Involving the nasal half of the visual field of
one eye and the temporal half of the visual field of the other
eye
Visual interpretations take place in the ________ portion of the brain?
Drop Instillation
TPA – vs DPA
 Therapeutic Pharmaceutical Application…when the
problem is known and you treat the condition
 Clean hands
 Explain procedure
 Diagnostic Pharmaceutical Application…when the
problem is unknown and you treat the symptoms
 Remember safety
 Inspect bottle
 Check expiration date
What is wrong with this picture?
Phenylephrine is used to stimulate the _________ muscle?
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Pharmacology: Diagnostic Agents Mydriatic Drugs
 Phenylephrine (Neo-Synephrine, Mydfrin)
 Strength: 2.5%, 10%
 Effective: 4-6 hours
 Systemic Side Effects:
 Irregular heart beat, headache, hypertension, cardiac
arrest (very rare)
 Action: Stimulates the iris dilator muscle
Pharmacology: Diagnostic Agents
Cycloplegic Drugs
 Tropicamide (Mydriacyl)
 Strength: 0.5%, 1%
 Effective: 5-6 hours
 Systemic Side Effects: Uncommon
Cyclopentolate paralyzes both the ________ and ________ ?
Therapeutic medications are use to _________ disease?
Pharmacology: Diagnostic Agents
Cycloplegic Drugs
 Cyclopentolate (Cyclogel)
 Strength: 1.0% and 2.0%
 Effective 24 hours
 Side Effects: Dry mouth, excitation, facial flushing,
tachycardia, angle closure due to dilation
 Action: Paralyzes the sphincter muscle of the iris (dilation)
and the ciliary muscle (prevent accommodation)
Pharmacology: Diagnostic Agents Stains
 Fluorescein…used to stain cornea surface
 Strips
 Mixed with anesthetic
 Injected (angiography)
 Rose Bengal…used to stain dead cells
_________ pharmaceutical applications drugs are used to treat symptoms?
Mydriacyl is used to ________ the pupil?
Pharmacology: Anesthetics
 Commonly used anesthetics:
 Proparacaine 0.5%
 Tetracaine 0.5%
 Lidocaine 1.0%-5.0%
 Benoxinate plus fluorescein (Fluress)
 Proparacaine plus fluorescein (Fluoracaine)
Pharmacology: Therapeutic Agents
 Miotics
 Action: contraction of the iris sphincter muscle
(pupil constriction)
 Use: lowering of intraocular pressure by improving
drainage of the aqueous humor through the
trabecular meshwork.
What is the typical duration for routine anesthetics?
Fluoracaine is a combo drug that uses ________ and ________ ?
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Pharmacology: Therapeutic Agents
 Glaucoma Treating Drugs
 Adrenergic-blocking agents

Timolol, Betaxolol, Levobunolol
 Adrenergic-stimulating agents
 Epinephrine
 Dipiverfrin
 Carbonic Anhydrase Inhibitors
 Acetazolamide
 Methazolamide
 Dorzolamide
Pharmacology: Therapeutic Agents
 Glaucoma Treating
Drugs
 Alpha Agonists
 Apraclonidine
 Brimonidine
 Protaglandin Analogs
 Bimatoprost
 Latanoprost
 Travoprost
Miotic medications are used to ________ the pupil?
Timilol is a beta-blocker medication used in the treatment of _______
Pharmacology: Therapeutic Agents
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Antibiotics
Antivirals
Antifungals
Corticosteroids…prevents swelling
Non-steroidal Anti-inflammatory Drugs (NSAIDS)
Decongestants
Antihistamines
Mast Cell Stabilizers
Lubricants
Objectives
 Determine Types
 Procedures
 Testing
 Eligibility
 Terminology
 Definitions
Ophthetic is a medication used to _________ the eye?
Lasers (directed energy)
 Broad Beam Lasers
A broad beam laser uses a relatively large
beam diameter (from 6.0 to 8.0 millimeters)
that can be manipulated to ablate the cornea.
The broad-beam laser results in the shortest
procedure time. This speed creates less
likelihood of overcorrection and decentration
- a complication caused by movement of the
pupil. A disadvantage is an increased
possibility of center islands - a complication
related to ablation. However,
ophthalmologists have learned to decrease the
incidence of center islands by using several
short laser pulses to ablate the cornea instead
of one longer one.
Lasers Cont…
 Spot Scanning Lasers
These systems have the potential to
produce the smoothest ablations
and use radar technology to track
the eye's movement. They also have
the potential to treat irregular
astigmatism and link to
topography. These lasers must be
linked to eye tracking to ensure
proper centration
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Terminology
Pictures
Flap Procedures- surgeon cuts a flap in the cornea in order to access the
underlying tissue
 LASIK – Laser-Assisted In Situ Keratomileusis Keratomileusis…treats
nearsighted, farsighted, and astigmatism…flap in the stroma, then uses an
eximer laser to remove material flap
 LASEK – Laser Epithelial Keratomileusis… cuts flap in the epithelial only.
For those who flat or thin corneas
 Epi-LASEK – surgeon does not use blade or alcohol, but uses an
epikeratome which separates epithelial layers and crates a epithelial sheet
 ALK – Automated Lamellar Keratoplasty…treats high levels of
nearsightedness and mild farsightedness
1
Can you identify the type of
procedure?
2
Call it
Pictures
Can you identify the type of
procedure?
2
1
Lasik
RK
Call it
cataract
Call it
glaucoma
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Call it
Call it
keratoconus
neovascularization
Call it
Call it
PVD
Macular Degeneration
Call it
Questions
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Farsighted
What is the purpose of the fitting triangle?
Which tonometers require an anesthetic?
What instrument is used to obtain a prescription
from a contact or ophthalmic lens?
What is the heaviest lens material?
Retinal detachment
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Questions

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
What is the difference between acuity and
accommodation?
Spell the scientific name for your eyelid
______________?
What percentage of water is in a low water content
______ or high water content _______ contact lens.
Review Questions
 The point where the upper and lower eyelids meet is called?
Questions



The person who normally grinds lenses is called a(n)
_________________?
What is the difference between a mydriactic and
miotic?
What is the definition of the word “plano”?
Review Questions
 The eyelid will protect your eyes from what?
 What main muscles raises the eyelid?
 The blockage of the meibomian gland is called the ___________ when
it causes pain, and the _________ when it does not cause pain?
 What is a good tear break up time?
 What is amblyopia?
Review Questions
 What is the difference between visual acuity and accommodation?
 What is decentration?
 Convert to spherical equivalent
- 1.50 – 1.00 X 180
- 2.25 – 1.50 X 120
 What is the main layer of the eye lid?
Review Questions
 Which is the heaviest lens material?
 What is the ora serrata
 Name a test performed binocularly?
 What comprises the vascular layer?
 Through a prism the image deviates which way?
 _________ is the merging of images from each eye into one image?
 Name one of two indentation tonometers
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Review Questions
Review Questions
 The drain port for tears is called?
 Identify the name for the parts of the conjunctiva on the eye and back
of the eyelid
 What is the difference between abduction and adduction?
 Where is the eye normally resting on a eso patient?
 What is the total power of the eye_____, the cornea _____ and the
crystalline lens____?
 Transpose this Rx + 1.25 + 1.25 X 090
- 1.75 + 2.00 X 180
 What is the strongest bone of the bony orbit?
Review Questions
Review Questions
 What are the layers of a tear film?
 -1.00 -1.00 x 090
Answer______________
 Where is tear mucin produced?
Answer______________
Answer______________
 Why is the tear film important in contact lens wear?
 - 2.50 -1.50 x 103
 - 0.50 -2.00 x 008
 -1.00 -0.50 x 162
Answer______________
 -1.00 -1.50 x 160
Answer______________
 + 2.50 -1.50 x 103
 - 5.00 -3.00 x 088
Answer______________
 -2.50 -1.00 x 029
Answer______________
 What is stereopsis?
 -3.00 -1.50 x 095
Answer______________
Answer______________
Review Questions
Review
 Opia means what?

Transpose the following Rx to Near Vision
Only aka NVO, SVN, reading glasses


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




-2.00 -1.00 x 080
-1.50 -2.00 x 180
+3.00 OU
Answer ________________
________________
-1.00 – 0.50 x 010
-2.00 -0.75 x 100
+1.25 OU
Answer________________
________________
 What is the difference between a tropia and a phoria?

-4.00 -0.25 x 090

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
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




-1.00 -0.50 x 098
+2.00 OU
Answer ________________
________________
+2.50 -1.00 x 090
+1.00 -0.75 x 180
+2.25 OU
Answer ________________
________________
 Avascular means what?
 How many extra-ocular muscles are oblique?
67
Review Questions
Review Questions
 Identify the name for the parts of the conjunctiva on the eye and back
 Where does aqueous drain?
 What drug is used to slow aqueous production?
of the eyelid____ and on the ball of the _____ and where they join
______?
 What test checks your central 20 degrees?
 Name the five parts of the cornea?
 What is the difference between versions and vergence?
 Name the parts of a frame?
 Analyph glasses are used with what test?
 What is the strongest bone of the bony orbit?
Questions
 A Corneal Topography is used to determine the ______
________ of a cornea?
 Corneal Topography is used in diagnosis and treatment of
_______ and _____ _____?
 The most accurate map is the _____?
 The _____ map uses Snell’s Law?
 Pachymetry is used to measure _____ ____?
 Pachymetry is used to diagnosis and treat _______ and
Test Tips
_______?
How To Study
 Provide enough time to cover all subjects
 Interactive
 Flash cards
Study Pace
 Don’t cram…study like you want to pass the
test
 Notes
 Study, break, review, preview, and study
 Tape record notes
 No more than two hours a one time
 Study groups
 Environment
 Scented candles
 Use travel time to study
 Record your notes
 Active learning
 Keep body and mind awake
68
Before the Test
 Find the location of test early
 Don’t arrive too early on the day of the test
 Build your confidence by reviewing condensed
notes
Be patient when you are handed the test, your time
doesn’t start right away
Remain calm
How to take a Multiple Choice
Test
Recommended References
 “Self Study Course for Optometric Assisting” by AOA
Paraoptometric Section
 “The Ophthalmic Assistant” by Stein & Slatt (8 th
Edition-Stein, Stein & Freeman)
 “System for Ophthalmic Dispensing” by Brooks and
Borish
 “Dictionary of Eye Terminology by Cassin & Solomon
 YoYoBrain Web site
More Test Taking Tips
 Take your time but be aware of the time

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
Memory dump
Answer easy questions first
Mark difficult questions, return to them later
Multiple choice are T/F question arranged in
groups
Only one totally correct answer
Eliminate obvious false choices
Pick the most complete answer
Look for contextual clues
Graphics Provided By:
Eyemaginations
Essilor (Pete Hanlin)
*The
first hour = 50 questions
 Read all the questions and answers completely
 Mark your answer sheet carefully
 Once you mark your answer, don’t go back and
change it without good reason
Good Luck!
[email protected]
The person who makes a success of living is the one
who sees his goal steadily and aims for it
unswervingly. That is dedication.
Cecil B. DeMille
(1881 - 1959)
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