Accomodation & Its Anomalies

1. Accommodation and its Anomalies
11th September 2020
DR M SAQUIB
Vice Principal , G.S.Medical College & Hospital
MBBS,MS , FSCEH DELHI,FHVDESAI PUNE,
EX REGISTRARA JNMCH,AMU
CONSULTANT OPHTHALMOLOGIST
HOD D/O OPHTHALMOLOGY
G.S .MEDICAL COLLEGE
Founder sec: MEDICS India ,
Mail-dms2k5@gmail.com , 9634123800

2. Physiological – Presbyopia
Pharmacological –Cycloplegia
Insufficiency of Accomodation
Paralysis of Accomodation
Spasm of Accomodation
Ill sustained Accomodation
Inertia of Accomodation2

3. 3

4. ACCOMMODATION : -The facility enabling the change
in dioptric power of the crystalline lens thereby altering
the focus of the eye.
▸ Emmetropic Eye far Point –Infinity
▸ Near Point varies with Age
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Age (Years) Amplitude Of Accomodation Near Point (cm)
10 14 D 7
20 10 D 10
30 7 D 14
40 4 D 25
50 2 D 50
60 1 D 100

5. Amplitude of Accommodation:
▸ A = P – R
( P , Diopteric power value for near distance , R-Diopteric power value for far distance )
▸ 100/7 - 1/∞ = 14 D ( At age of 10 years near point 7 cm)
▸ 100/25 – 1/ ∞ = 4 Dioptres
▸ 100/100-1/ ∞ = 1 D
▸
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6. Presbyopia
▸ Physiological Age related decrease in the
amplitude of accommodation leading to a
progressive fall in near vision.
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7. Causes
▸ Age Related Change in the Lens
▸ Decrease elasticity of Lens capsule
▸ Increase in size and hardness of lens
and its substance
▸ Age-related decline in Ciliary muscle
Power
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8. Premature Presbyopia
▸ Uncorrected Hypermetropia
▸ Premature sclerosis of the Crystalline lens
▸ Presenile weakness of ciliary muscle
▸ Chronic Simple Glaucoma
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10. R
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11. ▸ https://www.youtube.com/watch?v=1yI
pyitm6eE
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12. Symptoms
▸ Diificulty in near vision
▸ Asthenopic symptom
▸ Intermitten Diplopia
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13. Pre-senile cataract
▸ Cataract is likely to reduce accommodation
▸ May be unilateral.
▸ Unequal reading adds .
▸ May have reduced VA.
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14. ▸ Determination of reading addition
▸ Objective - Dynamic Retinoscopy
▸ Subjective :
▸ (A) Complete Distance Refraction.
▸ (B) Measure Amplitudes Of Accommodation
▸ (C) Use Amplitudes As A STARTING Point To
Calculate An Approximate Reading Addition.
▸ -Rule Of Thumb - Leave 1/3rd Accommodation In
Reserve.
▸ Check Clarity And Range. Double Check With
+&Additions.14

15. ▸ Insufficiency of accommodation
▸ Etiology :
▸ 1)Premature sclerosis of lens.
▸ 2)Weakness of ciliary muscle due to systemic
causes: Debilitating illness( anemia, toxemia,
malnutrition, diabetes mellitus, pregnancy, stress
etc.
▸ 3)Weakness of ciliary muscle due to local causes:
POAG(primary open angle glaucoma), mild cyclitis
) as during onset of sympathetic ophthalmia.
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▸ Insufficiency of accommodation

16. Insufficiency of accommodation
▸ Definition :
▸ Condition in which accommodative power is
constantly less than lower limit of normal range
according to patient’s age
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17. Insufficiency of accommodation
▸ Accommodative power is significantly less than
the normal physiological limits for the patient’s
age
▸ Symptoms of insufficiency
▸ Asthenopia
▸ Blurred vision for near work
▸ Over- or under-convergence
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18. Causes
▸ Premature sclerosis of Lens
▸ Weakness of Ciliary Muscles due systemic cause
of muscle fatigue such as debilitating illness
,anaemia ,toxemia of pregnancy ,stress , etc
▸ Weakness of Ciliary Muscles associated with
Open Angle Glaucoma
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19. 1) Identification & treatment of any systemic cause.
2) Any refractive error should be corrected & if vision for
near work is seriously blurred then additional near correction
has to be prescribed same as presbyopia.
▸ 3) If associated with convergence excess then full spherical
correction.
▸ 4) Convergence insufficiency is there, then base in prisms
can be added.
▸ 5) Prismatic correction added should bring near point of
convergence to same distance as near point of
accommodation
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▸ TREATMENT OF INSUFFICIENCY

20. ▸ 6) Weakest convex lenses should be prescribed, so as to
exercise and stimulate accommodation.
▸ 7) After recovery additional correction should be made
weaker and weaker from time to time.
▸ 8) Accommodative exercises.
▸ – While do exercises patient should wear correction for
distance.
▸ – Should be done simultaneously in both eyes, even if
associated with convergence insufficiency.
– But with convergence excess then the exercise should done
with one eye alternately.
▸ – Accommodation test card exercise.
▸ Accommodative exercises useless in generalized debility
and sclerosis of lens20

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22. SPASM OF ACCOMODATION
▸ Abnormally Excess accommodation
▸ Cause- Drug Induced – Strong meiotic
▸ Children attempts to compensate refractive error
▸ Excessive near work in Unfavorable Condition ( Bad
illumination ,bad reading position ,stress of neurosis ,
mental stress, anxiety )
▸ Clinical Features-
▸ Blurred vision depending on patient’s refractive status.
▸ Macropsia. Asthenopia during close work.
▸ Pain (brows/headache).
▸ Poor concentration. Miosis.
▸ Convergence anomalies (excess or insufficiency)22

23. Treatment
▸ Investigation:-Cycloplegic refraction used to
determine true refraction.(atropine drops for 2-4
weeks or more)
▸ Aetiology:-Spasm can be further categorized into:
▸ (a) Functional spasm. (b) Organic spasm.
▸ Relaxation of Ciliary Muscles by Atropine
▸ Corrective measures
▸ Assurance ,Psychotheapy23

24. ▸ PARALYSIS OF ACCOMMODATION
▸ May be partial or total, unilateral or bilateral. Signs and
symptoms
▸ Blurred vision
▸ Micropsia -More accommodative effort required to see
near object which is then perceived to be nearer than it
actually is and therefore smaller.
▸ Markedly reduced amplitude of accommodation.
▸ If lesion is localized to the lens or ciliary body then these
will be the only signs and symptoms.
▸ If III rd. Oculomotor nerve is affected then there will be
other signs. Oculomotor nerve innervates muscles that
enable most movements of the eye and that raise the
eyelid.24

25. ▸ PARALYSIS OF ACCOMMODATION
▸ Etiology
▸ Congenital Defects - No Ciliary Muscle.
▸ Cycloplegic Drugs (Atropine) , Systemic Drugs.
Degenerative Conditions E.G. Parkinson’s-Exogenous
Poisons E.G., Snake Bites, Bee Stings.
III N Lesion (Tumors, Aneurysm , Hemorrhage).
Ocular Disease (Anterior Uveitis- Glaucoma).
Trauma To Head Or Eye (Temporary Or Permanent Paralysis-
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26. ▸ PARALYSIS OF ACCOMMODATION
Clinical Feature:
▸ Blurring Of Near Vision
▸ Photophobia/Glare
▸ Abnormal reading of near point
TREATMENT :
▸ Self recovery
▸ Dark glasses are effective in reducing the glare.
▸ Convex lenses for near vision may be prescribed
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27. Treatment
▸ Optical Treatment
▸ Surgical Treatment
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