Download Ophthalmic Surgery

Ophthalmic Surgery
Surgery of the Eyes
Anatomy of the Eye
 Bony Orbit – two
orbital cavities
 7 bones form the
orbit






Maxilla
Palatine
Frontal
Sphenoid
Zygomatic
Ethmoid
Lacrimal
Anatomy of the Eye
 Bony Orbit
 Above – ant cranial fossa, frontal sinus
 Medial – nasal cavity
 Below – maxillary sinus
 Laterally - middle cranial and temporal
fossae
 Periosteum of bony orbit is continuous
with dura mater
Anatomy of the Eye
 Contents of the
Bony Orbit





Eyeball
Muscles
Nerves
Vessels
Other nerves and
vessels of facial
area around socket
Lacrimal apparatus
 Lacrimal gland-
lateral

Produces tears
and secretes
them through a
series of ducts
into the
conjunctival sac
 Puncta -
medial- opening
Lacrimal apparatus
 Lacrimal
canaliculi

Passage between
conjunctiva and
the Lacrimal sac
 Nasolacrimal
duct

Directs to the
inferior meatus of
the nose
Conjunctiva
 Thin transparent mucous membrane,
divided into two parts


Palpebral – lines back of eyelids, contains
the puncta
Bulbar - lines front of globe, allows sclera
to show through
Conjunctiva
 Continuous at
limbus with anterior
epithelium of
cornea
 Conjunctival sac,
with an opening in
front of eye
between margins of
eyelids called the
Palpebral fissure
Eyelids

Musculofibrinous folds



Protect globe and eye from light
Upper larger and more mobile
Canthi – medial and lateral angles on edge of
eye
Eyelids
 Obicularis
oculi muscle


Circular
muscle acts
as a sphincter
Closes eye
Eyelids
 Levator muscle


Opens upper lid
Innervated by the third cranial nerve and relaxing
of orbicular muscle
Eyelids
 Layers of eyelid




Skin
Subcutaneous with
lymphatics
Muscles
Tarsal cartilage –
dense fibrous
tissue, forms the
framework of the
lids

Anchored by medial
and lateral
palpebral ligaments
Eyelids
 Layers of eyelid


Cilia / eyelashes
Meibomian glands –
post to lashes


Secretes a
sebaceous
substance that
keeps the lids from
adhering to each
other
Punctum lacrimale –
near med edges of
each eyelid
Muscles of the Eye
Extrinsic –
inserted into
sclera by tendons
that arise from
back of orbit
(except the
Inferior oblique)


Work in pairs –
antagonistic
Muscles of the Eye
 4 rectus – insert on
side - superior,
inferior, medial,
lateral
 2 oblique – insert
on back – superior
and inferior
Muscles of the Eye
 Muscles are supplied by the Cranial Nerves
 3rd – oculomotor- all ocular muscles except
lateral rectus and superior oblique
 4th – trochlear- superior oblique
 6th – abducens- lateral rectus muscle
Eye Muscle Simulator
 http://rad.usuhs.mil/rad/eye_simulator/e
yesim.htm
 Includes a simulator on how eye
muscles work and how the cranial
nerves effect them
Globe
 Eyeball or Oculus
 O.D. - Oculus Dexter – right eye
 O.S. – Oculus Sinister – left eye
 Supported on a cushion of fat and fascia
Layers or Tunics
 Corneoscleral
 Cornea
 Sclera
 Choroid
 Retina
External - Corneoscleral
 Sclera - joins cornea at limbus
transitional zone




Opaque layer – white
Collatgenous fibers connected with fascia
Receives tendons
Pierced by ciliary arteries and nerves and
posteriorly by the optic nerve
Cornea
 Clear, transparent
anterior portion of the
eye
 Curvature enables it to
function as an
important refractive
medium
 Continuous with the
sclera
Cornea
 5 layers
 Bowman's
membrane



Connective tissue
fibers
Forms a barrier to
trauma / infection
If damaged it does
not regenerate
and a permanent
scar is left
Cornea
 5 layers
 Stroma


90% of corneal
thickness
Multiple lamellar
fibers
Cornea
 5 layers
 Descemet’s
membrane


Thin membrane
between
endothelium and
substantia propria
(stroma)
Can become
inflamed and
herniate
Cornea
 5 layers
 Endothelium



Single layer of
cells that do not
regenerate
Responsible for
the proper state
of dehydration
that keeps the
cornea clear
Damage causes
corneal edema
and loss of
transparency
Choroid
 Middle vascular
pigmented layer

Main source of
nourishment of
receptor cell and
pigment epithelial
layer of the retina
Choroid
 Iris


Regulates light entering eye, assists with clear
images
Pupil is central opening
Retina


Thin transparent
membrane
Nerve fibers from
the retina converge
to become the optic
nerve (II)
Retina, cont.
 Optic disk (blind
spot)- point at
which nerve enters
the eyeball

Optic nerve travels
to contralateral side
of brain
Retina, cont.
 Sensory Retina

Pigment epithelium – single layer – for O2 and
nutrients


Photoreceptor cells
Macula Lutea – yellow spot, center of retina, 2mm
from optic disk
 Fovea centralis – pit of closely packed cones in
center of the macula – highest resolution and
central vision.
Retina, cont.
 Sensory Retina

Rods and cones



Cones- stimulated
by light of different
colors (color-vision)
Rods- responds to
dim light (nightvision)
Respond to light
energy and initiate
the neural response,
which goes to
occipital cortex for
interpretation
Humors
 Fluid – gives shape
 Aqueous- anterior
cavity – fills anterior
and posterior
chambers


Transparent fluid,
produced by the
cilliary body
Passes from the
posterior to the
anterior chamber,
then to the venous
system through the
canal of Schlemm
Humors
 Fluid – gives shape
 Vitrous (vitreous
body) – fills posterior
cavity (posterior to
lens)



Glasslike,
transparent,
gelatinous mass
99% water, 1%
collagen and
hyalurinic acid
fills 4/5ths of the
eyeball
Choroid
 Ciliary body
(intrinsic muscle)



Extension of
choroidal blood
vessels, muscle
mass and extension
of neuroepithelium of
retina
Effects
accommodation
Secrets aqueous
humor
Choroid
 Iris
(intrinsic muscle)



Thin membrane, is
the anterior portion of
the middle layer, and
is situated in front of
the lens
Peripheral border
attached to the ciliary
body
Divides space
between cornea and
lens
Choroid
 Iris



Anterior
chamber
Posterior
chamber
Both filled with
aqueous
humor
Refraction of the Eye
 Refractive media – bends light so rays
strike Macular area



Myopia- nearsightedness- light rays focus in front
of the retina
Hyperopia- farsightedness- light rays focus
behind the retina
Cornea - greatest refractive power – variations
change it’s power
Refraction of the Eye
 Lens – suspended behind the pupillary
opening of the iris by the suspensory
ligament and zonular fibers which
expand and contract lens
(accommodation/focus)


Does not shed cells, cells become compressed
and hard.
Presbyopia- accommodation is lost with age as
lens loses elasticity – onset usually occurs
between age 40 to 45
Blood Supply
 Ophthalmic artery – for orbit and globe,
from internal carotid


Divided into globe, muscle and eyelid
branches
Central retinal artery/vein through optic
nerve and serve inner retina
Pathology
 Leading causes of visual impairment
and blindness



1st - Macular degeneration
2nd - Cataracts
3rd - Glaucoma
Pathology
 Macular degeneration
(1st)



Leading cause of vision
impairment in persons
over 50
Degeneration in the
macular area of the
retina of the eye
This condition will not,
in itself, lead to total
blindness
Pathology
 Macular degeneration (1st)
 Can lead to loss of central vision, making it
difficult to read or do fine work


Have patient look at a grid with each eye
separately.
If central vision is impaired the lines will appear
wavy instead of straight
Pathology
 Cataracts (2nd)
 Opacification of the
lens


From Greek word,
means mist of a
waterfall
Common form results
from aging, but may be
congenital or caused
by infection, injury,
radiation exposure,
complication of
diabetes, and smoking
Pathology
 Cataracts
 Awareness and treatment goes back over
3,000 years



“Couching or reclination” tx practiced sporadically
from 2,000-1,000 BC until 1745
1745 Jacques Daviel, a French surgeon,
performed the first deliberate lens extraction on a
monk from a local monastery
18th century attempts to implant lenses were
unsuccessful
Pathology
 Cataracts

Modern implants evolved from the observation in
WWII that noted a lack of reactivity to plastic
fragments from shattered plane canopies that
penetrated the eyes of fighter pilots
Pathology
 Glaucoma (3rd)
 Increased intraocular
pressure


Results in atrophy
of the optic nerve
Occurs when the
aqueous humor
drains from the eye
to slowly to keep up
with production
Pathology
 Retinal disorders
 Damage to the
sensory receiver of
light perception



Detached retina
(pictured)
Macular
degeneration
Diabetic
retinopathy
Pathology
 Corneal transplant
 First performed around 1817
 Failed, as they used animal tissue
(xenograft) instead of human tissue
(allograft)
 First to remain clear in 1905
 1950 Ramone Castroviejo developed the
procedure, and promoted the donation of
eyes after death that resulted in the
formation of eye banks throughout the world
Pathology
 Ametropia

Imperfect refractive powers of the eye in which
the principal focus does not lie on the retina, as in
myopia, hyperopia, and astigmatism
Pathology
 Astigmatism

A form of ametropia in which the refraction of a
ray of light is spread over a diffuse area, rather
than sharply focused on the retina, due to
differences in the curvature in various areas of
the cornea and lens
Pathology
 Aphakia - absence of the crystalline
lens of the eye
Aphakia with Soemmering's ring formation.
Patient Concerns
 Preoperatively
 Orient patient to environment (for visual
and/or hearing impairment)
 Approach patient from non-affected side
 If walking a patient into OR, offer your arm
to lead them instead of pulling them
 Let them know desired results of eye
drops and sedation
 Explain what to expect from anesthetic
 Explain routine of intraoperative period
Patient Concerns
 Preoperatively
 Explain what to expect immediately after
surgery
 They may be restless, have discomfort
and anxiety
 There may be limitations in mobility and
prosthesis (positioning)
 Ask about medical problems, general and
ophthalmic (i.e. Diabetes, glaucoma, etc.)
 Ask about medications and allergies
Patient Concerns
 Postoperatively
 Give verbal and written instructions
regarding


Use of eye drops, other meds
Information on limitations on activities
(Awareness that vision with only one eye
interferes with depth perception, i.e. Going
down steps, driving, etc.)
Patient Concerns
 Postoperatively
 Give verbal and written instructions
regarding




Wound care
Signs and symptom of complications
Who to call with questions or concerns
Clinical appointment times or phone number
to schedule
Anesthesia
 Understand that most surgery is under
local anesthesia
 Should be quiet and peaceful
 Most patients are sedated
 There may be an O2 tube under drapes
Anesthesia
 Topical
 For cataract-extraction

May be supplemented with infiltration
anesthesia in anterior chamber
 Infiltration
 Injected beneath skin, subconjunctival or
into the Tenon capsule (thin connective
tissue envelope behind the conjunctiva
Anesthesia
 Peribulbar (preferred)
 Around soft tissue of globe with needle to
floor and roof of orbit
 Retrobulbar
 Injection into base of eyelids at the orbital
margins or behind the eyeball to block
ciliary ganglion

Injected 10-15 minutes prior to surgery to
paralyze extraocular muscles
Positioning
 Supine
 Stabilize head with 1” paper tape or other
head holding device
 Protect bony prominences, provide
alignment to body
Prepping
 If eyelashes are clipped, do before prepping
 Spread water soluble lubricant on scissors to
catch hairs
 May order 5% povodine-iodine on
conjunctiva

1 –2 drops on surface before prep - then rinse
with NS
Prepping
 Cleanse eyelids of operative eye, lid margins,
lashes, eyebrows and surrounding skin
 Lid margins cleaned by everting the lids and
cleaning with cotton-tipped applicator
moistened with disinfectant.
 Don’t allow entry into eye or ear.
 Irrigate with NS in irrigation bulb, should flow
medially to laterally
Draping
 Eliminate lint and fiber particles
 Water repellent
 Adequate air exchange
 Place Mayo stand above the patient’s
chest or face shield, drape over
Draping
 Use one-piece fenestrated drape
 Plastic, sticky around hole
 ALT: head drape with fenestrated
plastic eye sheet
 A fluid drainage bag with wicking strip
may be adhered to eye sheet
Surgical Needs
 Be sure implants or prostheses are
present
 Microscope drape or sterile handles
 Field with lint-free barriers
 Gloves lubricant free or wiped
 Powder irritates the cornea
Surgical Needs
 Instrument part used in wound not
touched with gloves
 Debris cleaned with cellulose sponge
 Meds instilled into eyes
 Hold light pressure over lacrimal duct for 1
minute to prevent system absorption and
drying inner canthus after each drop
Surgical Needs
 Let patient know what to expect from
meds.
 Protect cornea after anesthetic instilled
to prevent damage
 Need to irrigate eye regularly to prevent
corneal drying.
 Know that pressure on eye/tension or
traction on ocular muscles can produce
bradycardia.
Instruments
 Microscopic, nonreflective finish
 Storage cases protect tips and cutting
surfaces
 Inspect under magnifiers each time for
burrs, nicks, alignment
 Clean with non fibrous sponge
Instruments
 Know name and purpose of
instruments
 Place on Mayo in order of use
 Clean in ultrasonic with each not
touching another
 Rinse and dry with blower, not cloth
Instruments
 No instrument milk on irrigating
cannulas to prevent damage to eye
 Do routine maintenance to sharpen,
realign, and adjust
 Tonometer- instrument used for
measuring IOP
Instruments
 Fixation forceps – hold tissue or
provide traction before incision

Angled tooth that overlaps for secure
fixation
 Suturing forceps single toothed at right
angle
 Tying forceps with flat platform to hold
suture
Suture
 4-0 to 10-0
 Handle as little as possible – prevent
weakening and fraying
 Gut and collagen should be rinsed
before use
 Needles are delicate, check for burrs
and handle carefully
Drugs
 Alex- 669, 670 & 671

“Medications Used During Opthalmic
Surgery”

Table 18-1
Dressings
 Prevent palpebral movements
 Protect wound from contaminants
 Absorb blood and tears
 Area cleansed with saline sponges
 Antibiotic ointment may be spread over
plastic repairs, lids and lashes to
prevent sticking to dressing
Dressings
 Dressing
 Sterile eye pad with tape
 After intraocular – perforated aluminum plate
/ shield prevents external pressure on eyes
 Pressure dressing – pad with roller gauze
around head prevents eye globe movement
 Cataract – may use collage corneal shields –
rehydrated with anti-infective- antiinflammatory solution for dressing
 May have no dressing
Surgical Interventions
 Removal of Chalazion
 Incision and curettage of a chronic
granulomatous tumor or cyst of one or
more of the meibomian glands in the
tarsal plate of the eyelid

Performed under local anesthesia
Surgical Interventions
 Repair of Entropion
 Perform a blepharoplasty to correct




Entropion- turning inward of the lower lid
margin
In-turned lashes and skin rub and irritate
the cornea
Seldom occurs in people under age 40
Performed under local anesthesia
Surgical Interventions
 Repair of Ectropion
 Lateral canthal sling repositions and
tightens the lower lid in a horizontal
direction



Ectropion- sagging and eversion of the lower
lid
Usually bilateral, and usually in older persons
Symptoms include tearing, conjunctival
infection and irritation, and inadequate
corneal protection leading to corneal injury
Surgical Interventions
 Surgery for Ptosis
 Correction of drooping of the upper lid,
commonly by a levator apponeurosis
repair


Incision is made in the upper lid apponeurosis
is dissected, divided, and reattached
proximally with interrupted 6-0 n.a.
Performed under local anesthetic- awake
patient is asked to look forward so the sutures
may be adjusted
Surgical Interventions
 Dacryocystorhinostomy
 Establishment of a new tear passageway
for drainage into the nasal cavity


Performed for chronic dacryocystitis (infection
of the lacrimal sac) causing resistant
obstruction of the nasolacrimal duct
Performed under general anesthesia
Surgical Interventions
 Evisceration
 Removal of the contents of the eye,
leaving intact the sclera and the attached
muscles

Implant may be placed within the empty shell
Surgical Interventions
 Enucleation
 Removal of the entire eyeball, usually with
insertion of a round implant into the
socket to replace the globe

May use donor sclera to reattach the muscles
to the globe for movement
Surgical Interventions
 Exenteration
 Removal of the entire orbital contents,
including the periosteum


Performed for certain malignancies of the
globe or orbit
Procedure may or may not include removal of
the eyelids
Surgical Interventions
 Stabismus

Inability to direct the
two eyes on the
same object
because of lack of
coordination of the
extraocular
muscles
Surgical Interventions
 Stabismus
 Deviation commonly
corrected by:

Resection- removal of
a portion of the muscle
and attachment of the
cut ends- strengthens
the muscle
Surgical Interventions
 Stabismus
 Deviation commonly
corrected by:

Recession- severs the
muscle from its original
insertion with
reattachment more
posteriorly on the
sclera- weakens the
muscle
Surgical Interventions
 Pterygium excision
 Excision of a fleshy, triangular encroachment of
conjunctiva onto the peripheral area of the
cornea

Tend to be recurrent, so surgery is delayed until
vision is affected by encroachment on the visual
axis
Surgical Interventions
 Keratoplasty (aka- corneal transplant)
 Graft of tissue from one human eye to
another


Performed when the patients cornea is
thickened and opacified by disease or
degeneration, or if the transparency of the
cornea is impaired as the result of scars,
infections, or burns
Trephine
 A cutting instrument used to make a circular cut
of the cornea
Pathology
 Keratoplasty (aka- corneal transplant)
Surgical Interventions
 Radial Keratotomy
 Refractive procedure to correct myopia,
hyperopia, astigmatism, and aphakia



Series of precise, partial-thickness radial
incisions in the cornea
Results in a flattening of the cornea, which
reduces the refractive error
First performed in 1978
Surgical Interventions
 Radial Keratotomy
Surgical Interventions
 LASIK Surgery
 Refractive procedure to correct myopia,
hyperopia, astigmatism, and aphakia


Laser-assisted in-situ keratomileusis
Curvature of the cornea is modified using a
excimer laser
Surgical Interventions
 Cataract extraction
Surgical Interventions
 Cataract extraction- removal of the
opaque lens from the interior of the eye

ICCE- intracapsular cataract extraction




Removes the lens within its capsule
Rarely performed today
Requires breaking the zonules
Cryoprobe “frozen” to the lens
Surgical Interventions
 Cataract extraction
 ECCE- extracapsular cataract
extraction

Anterior capsule is ruptured and removed,
and the lens is expressed from the eye,
generally using phaecoemulsification
(ultrasonic energy with irrigation and
aspiration, aka cavitron unit)
Surgical Interventions
 Cataract extraction
 IOL- intraocular lens


Optics- clear round portion
Haptics- springs on either side- hold lens in
position
Surgical Interventions
 Iridectomy
 Removal of a section of iris tissue


Performed to reestablish communication
between the posterior and anterior chambers
Performed to treat glaucoma
Surgical Interventions
 Scleral buckling
 Performed to treat retinal detachment



Causes an intrusion or push into the eye at the site
Performed under general anesthesia
May use cryosurgery (cold) or diathermy (use of
high frequency current to generate heat for
electrocoagulation)
Surgical Interventions
 Vitrectomy
 Removal of all or
a part of the
vitreous body
(gel)

May also include
coagulation of
retinal vessels for
bleeding, which
causes the fluid to
become opaque
You made it through
Eyes!
Have a GREAT day!!! 