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HYPERMETROPIA
HYPERMETROPIA: PROGRAM
Hypermetropia: program I
• Generalities:
– Definition
– Etiology and epidemiology
– Signs and symptoms
• Classification:
– According to magnitude
– According to refraction
– According to the accomodative capacity
Hypermetropia: program II
•
Clinical exam:
–
–
–
–
–
VA: hypermetropia and age
Characteristics of the retinoscopy
Characteristics of the subjective exam
Low refraction cycloplegia
Binocularity: effect of the optical compensation
Hypermetropia: program III
• Prescription criteria:
–
–
–
–
–
Hypermetropes
Hypermetropes
Hypermetropes
Hypermetropes
Hypermetropes
from age 0 to 6
from age 6 to 20
between 20 and 45
between 45 and 65
older than 65
• Resolution of clinical cases
HYPERMETROPIA: GENERALITIES
Hypermetropia: Generalities I
• A condition in which the rays that come from a far
away object, the eye being accomodatively relaxed,
form their image behind the retina.
• The structural causes of hypermetropia can be:
– Small axial length of the eye
– Weak eye
– An error in the relation between the axial longitude
and the power
Hypermetropia: Generalities II
• Epidemiology:
– 66% of the population has a refractive error in the
range of +0,50D a +2,37D
• Etiology:
– Genetic influence
– Environment and visual demands
HYPERMETROPIA: CLASSIFICATION
Hypermetropia: Classification I
• According to the magnitude of the total
hypermetropia:
– Low hypermetropias: between +0,25 and +2,00 D
– Moderate hypermetropias: between +2,25 and
+5,00 D
– Elevated hypermetropias: above +5,00 D
Hypermetropia: Classification II
• According to refraction:
– H. Total (HT): Total magnitude of the hypermetropia. It is the value
of the retinoscopy, using an appropriate accomodation control. In
some cases the cycloplegic refraction can be necessary.
– H. Manifest (HM): that which the patient shows through the
subjective refraction. It is the part of the HT that, in some patients,
allows compensation through the lenses + (without diminishing VA
in DV)
– H. Latent (HL): that which does not appear in the realization of the
subjective exam. It is the part of the HT that, in some patients,
does not allow compensation (secondary to the excessive tone or
spasm of the ciliary muscle)
Hypermetropia: Classification III
H
TOTAL
=H
MANIFEST
+H
LATENT
• Example 1:
–
–
–
–
Youth of 16; no previous Rx
VAsc in DV: 20/20 in RE and LE
Retinoscopy: +3,50
Subjective: +1,00 (if the positive is augmented, the VA and
visual comfort from distances will be lost)
NOTE: Rx: refraction; sc: without correction; for the VA, the notation of Snellen has been used in
feet
Hypermetropia: Classification IV
• According to the accomodative capacity:
– H. Total (HT): Total magnitude of the hypermetropia. It is
the value of the retinoscopy, utilizing an appropriate
accomodation control. In some cases cycloplegic refraction
can be necessary.
– H. Absolute (HA): that which cannot be compensated for by
the accomodative capacity of the patient. It is responsible
for the fact that a hypermetrope cannot achieve a normal VA
in DV.
– H. Facultative (HF): that which can be compensated for by
the accomodative capacity of the patient.
Hypermetropia: Classification V
H
TOTAL
=H
FACULTATIVE
+H
ABSOLUTE
• Example 1:
–
–
–
–
Patient, 52-years-old ; no previous Rx
VAsc in DV: 20/40 en RE
Retinoscopy: +2,25
Positive minimum necessary in order to achieve an VA of
20/20: +1,50
– Subjective: +2,25
NOTE: Rx: refraction; sc: without correction; for the VA, we have used Snellen’s notation in feet
HYPERMETROPIA: CLINICAL EXAM
Hypermetropia: Clinical exam I
• Case history
–
–
–
–
–
Symptoms in NV
Symptoms of anticipated presbyopia
Lack of concentration
Elimination of task in NV
Occasional diplopia
Hypermetropia: Clinical exam II
• Visual acuity: The VA will be determined by:
– The grade of hypermetropia
– Age of the patient and accomodative capacity
– General state of health of the patient
• Previous concepts:
– Amplitude of monocular accomodation
– Methods to determine the amplitude of accomodation
– Amplitude of the comfortable accomodation
Hypermetropia, VA and age
Condition
Age
20
EMMETROPE
40
60
20
HYPERMETROPE
+2,50 sc
40
60
20
MYOPE
-2,50 sc
40
60
Am Accom.
total
Am. Accom.
Comfort
Necessary
Acco
m. DV
Expected
VA
DV
Necessary
Accom.
40cm
Expected
VA
40cm
Hypermetropia, VA and age
Condition
EMMETROPE
HYPERMETROPE
Age
Am Accom.
total
Am comfort.
Accom.
Necessary
Acco
m. DV
Expected
VA
DV
Necessary
Accom.
40cm
20
12,5
6,25
0
1
(20/20)
2,5
20/20
40
6,5
3,25
0
1
(20/20)
2,5
20/20
60
0,5
0,25
0
1
(20/20)
2,5
≤20/100
20
12,5
6,25
2,50
1
(20/20)
5,0
20/20
40
6,5
3,25
2,50
1
(20/20)
5,0
≈20/40
60
0,5
0,25
2,50
≤20/100
5,0
≤20/200
20
12,5
6,25
0
0,1
(20/200)
0
20/20
40
6,5
3,25
0
0,1
(20/200)
0
20/20
60
0,5
0,25
0
0,1
(20/200)
0
20/20
+2,50 sc
MYOPE
-2,50 sc
Expected
VA
40cm
Hypermetropia: Clinical exam III
• Retinoscopy without cycloplegia
–
–
–
–
Good fogging
Look for fluctuations in the reflex
Assess variations of the pupil’s diameter
Confirm astigmatisms
Hypermetropia: Clinical exam IV
IMPORTANT: Do not confuse mydriatic effect with cycloplegic effect
• Retinoscopy with cycloplegia
– When there is suspicion of a greater
hypermetropia than discovered in the retinoscopy
– When endotropias exist
– When there is very low collaboration
– Commonly used medications:
OPTIMAL
CYCLE
DURATION
EFFECT
RESIDUAL
ACCOM.
Atropina
24 – 48 h
12 – 18 días
+
Ciclopentolate
30’ – 45’
8 – 10 h
++
20’
2–5h
+++
MEDICATION
Tropicamide
Hypermetropia: Clinical exam V
• Subjective exam in hypermetropes:
– Begin the exam with the brute value of the
retinoscopy
– When the H. Total  H. Manifest special
considerations are not necessary
– When a significant grade of H. Latent exists the
subjective exam is an art
Hypermetropia: Clinical exam VI
– Subjective exam in cases of latent hypermetropia:
• Essential to maintain the fogging at all times
• The dioptric variations necessary to get a line VA are
not logical
• It is not always necessary to arrive at VA 1 the
monocular way
• The patient tends to reject or diminish retinoscopic
astigmatisms in the subjective exam (back yourself up
with keratometria)
• In anisometropias: guide yourself by the retinoscopy
Hypermetropia: clinical exam VII
• Binocularity and accomodation
– An uncorrected or partially corrected
hypermetropia can:
• Associate itself with more or less pronounced
myosis
• Associate itself to endodeviations, mainly in NV
• Simulate a fatigue or an accomodative insufficiency
HYPERMETROPIA: PRESCRIPTION
CRITERIA
Hypermetropia: Prescription criteria I
•
•
•
•
Patient’s age
Grade of hypermetropia
Symptoms
Binocular dysfunction associated
Hypermetropia: Prescription criteria II
• From 0 to 6 years of age
– Reason for the consultation:
•
•
•
•
School check-up.
It seems that one eye deviates.
Family history.
There do not tend to be subjective complaints.
Hpermetropia: Prescription criteria III
• From 0 to 6 years of age
– Hypermetropia < 3 D: does not tens to be prescribed,as
long as it is not found to be associated with a binocular
dysfunction, a low VA, or an astigmatism 1,50D.
– Hypermetropia >3 D. Generally prescribed (totally or
partially), since it can be associated with or induce:
•  VA.
•  development of binocular vision.
Hypermetropia: Prescription criteria IV
• From 0 to 6 years of age
– Hypermetropia + endotropia:
•
•
•
•
A cycloplegia tends to be necessary.
Evaluate deviation in DV and NV.
Evaluate the effect of positive lenses in NV.
Always prescribe the maximum positive power.
– Hypermetropia + exodeviations:
• Do not prescribe or PARCIALIZAR the prescription.
Hypermetropia: Prescription criteria V
• From 0 to 6 years of age
– Low bilateral vision (pathological cause): Total
prescription to reserve the accomodation for NV.
– Hypermetropia and anisometropia:
– Hypermetropia + external ocular infections:
Evaluate the necessity to prescribe in Hp > 1 D or
1,50 D.
Hypermetropia: Prescription criteria VI
• From 6 to 20 years of age
–
–
–
–
Up until puberty hypermetropia tends to diminish.
At these ages  demands on NV.
Diverse reasons for consultation.
Importance of latent hypermetropias.
Hypermetropia : Prescription criteria VII
• From 6 to 20 years of age
– Hypermetropia < 1,50D: does not tend to be
prescribed, as long as it is not found to be
associated with a binocular dysfunction or visual
fatigue in NV.
– Hypermetropia >1,50D. Generally prescribed for,
totally or partially, and especially if it is associated
with an astigmatism > 0,75D.
Hypermetropia : Prescription criteria VIII
• From 6 to 20 years of age
– Hypermetropia + endodeviation: total prescription.
Constant use or principally for NV
– Hypermetropia + exodeviations: bias the
prescription (without affecting the visual comfort
in NV)
Hypermetropia : Prescription criteria IX
• From 6 to 20 years of age
– Low bilateral vision (pathological cause): total prescription in
order to reserve the accomodation for NV.
– Hypermetropia and anisometropia:
• Up until 8-10 years of age we can prescribe for the total
anisometropia
•  10 years of age: prudence with anisometropias if they
have never before been prescribed for
– Hypermetropia + external ocular infections:
• Evaluate the necessity of prescribing in hypermetropias
> 1 D.
Hypermetropia : Prescription criteria X
• From 20 to 45 years of age
– Small hypermetropias give symptomology in NV.
– According to the grade of the hypermetropia, > 35 years of
age show signs of presbyopia.
– Reasons for consultation:
• Visual fatigue in NV.
• Conjunctival hyperaemia.
• Importance of latent hypermetropias.
Hypermetropia : Prescription criteria XI
• From 20 to 45 years of age
– Generally totally prescribed, as much when
associated with an astigmatism as when not.
Emphasizing its use for NV.
– Hypermetropia + exodeviations
– Hypermetropia and anisometropia
Hypermetropia : Prescription criteria XII
• From 45 to 65 years of age
– Age of appearance of presbyopia
– Glasses that were for near vision are now used for
distance vision.
– Latent hypermetropias become manifest.
– Facultative hypermetropias become absolute.
– Reasons for the consultation:
• Loss of VA in NV.
Hypermetropia : Prescription criteria XIII
• From 45 to 65 years of age
– Prescribe totally as much for DV as for the
corresponding addition for NV (it will permit
intermediate vision).
Hypermetropia : Prescription criteria XIV
• From 45 to 65 years of age
– Hypermetropia + exodeviations:
– Hypermetropia and anisometropia:
Hypermetropia : Prescription criteria XV
• Older than 65 years of age
– At ages > 65-years-old there can be a
diminishment of the hypermetropia (nuclear
cataracts).
– Relationship between elevated hypermetropia and
narrow anterior chamber.
HYPERMETROPIA: CASES
Hypermetropia: case 1-I
• QG, 39 years of age. Salesman.
• MC: Occasionally notes that he/she does not
see well in NV. Asthenopic symptoms when
reading.
• PH: Never worn glasses. Does not remember
previous visual revisions. No illnesses or
ingestion of medication.
• FH: Unimportant.
Hypermetropia : case 1-II
• Habitual VA in DV and NV:
– RE: 20/20; NV: 20/20
– LE: 20/20; NV: 20/25
• Binocularity in habitual conditions:
– Cover test:
• DV: ortho
• NV: low endophoria
– Proximal convergence: 10/12cm
Hypermetropia : case 1-III
• Retinoscopy:
– RE: +1,00
– LE: +1,50
• Subjective DV and VA:
– RE: +0,75; VA: 20/20
– LE: +1,25; VA: 20/20
– NV with the subjective: VA 20/20 in both eyes. Good comfort
• Amplitude of accomodation with the subjective:
– RE: 16cm≈6D
– LE: 16cm≈6D
• Ocular health exams: within normal limits
Hypermetropia : case 1-IV
• Complete diagnostic of the case
• Proposed treatment and plan of check-ups
• Possible evolution of the condition
Hypermetropia : case 1-V
• Complete diagnostic of the case
– Low hypermetropia manifests itself in both eyes
– The hypermetropia is facultative since the habitual
VA in DV is 20/20
– Endophoric tendency in NV without correction
– The rest of the test results within normal limits
Hypermetropia : case 1-VI
• Proposed treatment:
– Glasses with the value of the subjective:
• RE: +0,75
• LE: +1,25
– Use mainly for tasks involving NV.
– Can be worn for general use.
– Revision in two years or before if new
symtomology appears.
– Explain the condition to the patient.
Hypermetropia : case 1-VIII
• Possible evolution of the condition:
– Stability of the graduation until the appearance of
presbyopia.
Hypermetropia : case 2-I
• NP, 21-years-old. Student.
• MC: Visual fatigue in NV. To study the patient
uses glasses but symptoms continue
• PH: 2 years ago he/she wore glasses for NV
of +0,50 in both eyes. No illnesses or
ingestion of medication.
• FH: Irrelevant.
Hypermetropia : case 2-II
• Rx and habitual VA in DV and NV:
– REDV: 0,00; VADV: 20/20+; RENV: +0,50; VANV: 20/20
– LEDV: 0,00; VADV: 20/20+; LENV: +0,50; VANV: 20/20
Binocularity in habitual conditions:
– Cover test:
• DV: ortho
• NVcc: orthophoria
– Proximal convergence: 8/10cm
Hypermetropia : case 2-III
• Retinoscopy:
– RE: +2,75-0,50x180º
– LE: +3,50-0,50x180º
• Subjective DV and VA:
– RE: +0,50; VA: 20/20+
– LE: +0,75; VA: 20/20+
• Retinoscopy in NV (with the subjective):
– RE: +1,25 (fluctuates)
– LE: +1,50 (fluctuates)
• Ocular health tests: within normal limits
Hypermetropia : case 2-IV
• Are other tests necessary for a correct
diagnosis and treatment?
• Complete diagnostic of the case
• Proposed treatment and a plan of check-ups
• Possible evolution of the condition
Hypermetropia : case 2-V
• Are other tests necessary for a correct
diagnosis and treatment?
– Cycloplegia?
– Amplitude of accomodation?
Hypermetropia : case 2-VI
• Complete diagnostic of the case
– Moderate hypermetropia in AO. Significant latent
hypermetropia. Small manifest hypermetropia
– Low, direct astigmatism in both eyes in the
retinoscopy that is not accepted in the subjective
– The rest of the tests return result within normal
limits
Hypermetropia : case 2-VII
• Proposed treatment:
– Prescribe new glasses:
• RE: +1,75
• LE: +2,25
– Main use in NV. Use in DV is also recommended.
– Explain the condition to the patient
– New check-up in 3-4 months
Hypermetropia : case 2-VIII
• Possible evolution of the condition:
– It is hoped that with the passage of time the latent
hypermetropia will manifest itself
– The hypermetropic graduation in the glasses will
continue increasing up to the current value of the
retinoscopy or even a slightly superior value
– Greater dependence on the glasses with the passage
of time
HYPERMETROPIA : BIBLIOGRPHHY
Hypermetropia : bibliography
• Amos JF. Diagnosis and management in vision
care. Butterworth-Heinemann, 1987
• Milder B, Rubin ML. The fine art of prescribing
glasses. (2nd edition), Triad Publishing
company, 1991.
• Brookman KE. Refractive management of
ametropia. Butterworth-Heinemann, 1996
• Werner DL, Press LJ. Clinical pearls in
refractive care. Butterworth-Heinemann, 2002
Hypermetropia: bibliography
• http://www.wrongdiagnosis.com/h/hyperopia/in
tro.htm
• http://www.healthatoz.com/healthatoz/Atoz/enc
y/hyperopia.jsp
• http://www.eyemdlink.com/Condition.asp?Condi
tionID=229
• http://en.wikipedia.org/wiki/Hyperopia
• http://www.nlm.nih.gov/medlineplus/ency/articl
e/001020.htm
• http://www.tarso.com/Hiper.html