hypermetropia. hypermetropia: program hypermetropia: program i generalities: –definition...
TRANSCRIPT
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 from age 0 to 6– Hypermetropes from age 6 to 20 – Hypermetropes between 20 and 45– Hypermetropes between 45 and 65– Hypermetropes 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
• 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)
H TOTAL = H MANIFEST + H LATENT
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
• 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
H TOTAL = H FACULTATIVE + H ABSOLUTE
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 AgeAm Accom.
totalAm. Accom.
Comfort
Necessary
Accom. DV
ExpectedVA DV
NecessaryAccom. 40cm
ExpectedVA
40cm
EMMETROPE
20
40
60
HYPERMETROPE
+2,50 sc
20
40
60
MYOPE-2,50 sc
20
40
60
Hypermetropia, VA and age
Condition AgeAm Accom.
total
Am comfort
. Accom.
NecessaryAccom. DV
ExpectedVA DV
NecessaryAccom. 40cm
ExpectedVA
40cm
EMMETROPE
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
HYPERMETROPE
+2,50 sc
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
MYOPE-2,50 sc
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
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
• 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:
IMPORTANT: Do not confuse mydriatic effect with cycloplegic effect
MEDICATIONOPTIMAL CYCLE
DURATIONEFFECT
RESIDUAL ACCOM.
Atropina 24 – 48 h12 – 18
días+
Ciclopentolate 30’ – 45’ 8 – 10 h ++
Tropicamide 20’ 2 – 5 h +++
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/intro.htm
• http://www.healthatoz.com/healthatoz/Atoz/ency/hyperopia.jsp
• http://www.eyemdlink.com/Condition.asp?ConditionID=229
• http://en.wikipedia.org/wiki/Hyperopia• http://www.nlm.nih.gov/medlineplus/ency/
article/001020.htm• http://www.tarso.com/Hiper.html