The document discusses anisometropia, a condition characterized by unequal refraction in the eyes, and its tolerance levels, types, diagnosis, and treatment options. Aniseikonia, defined as unequal image sizes or shapes projected from the retina, is also explored, detailing its types, symptoms, and treatments. Both conditions can lead to issues with binocular vision and depth perception, with various corrective measures available depending on the severity and type of each condition.

1. 𝗔𝗡𝗜𝗦𝗢𝗠𝗘𝗧𝗥𝗢𝗣𝗜𝗔
𝗔𝗡𝗗
𝗔𝗡𝗜𝗦𝗘𝗜𝗞𝗢𝗡𝗜𝗔

2. 𝗔𝗡𝗜𝗦𝗢𝗠𝗘𝗧𝗥𝗢𝗣𝗜𝗔
• The optical state with equal refraction in two eyes is termed
‘ISOMETROPIA ’. When the total refraction of the two eyeS iS
unequal the condition iS called ‘ ANISOMETROPIA ’.
• An anisometropia up to 2.5 D is well tolerated and that between 2.5
and 4 D can be tolerated depending upon the individual sensitivity.
However, if it is more than 4D , it is not tolerated and is a matter of
concern.

3. 𝗘𝗧𝗜𝗢𝗟𝗢𝗚𝗬
𝟭- 𝗖𝗼𝗻𝗴𝗲𝗻𝗶𝘁𝗮𝗹 𝗮𝗻𝗱 𝗱𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁𝗮𝗹 𝗮𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮
𝟮- 𝗔𝗰𝗾𝘂𝗶𝗿𝗲𝗱 𝗮𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮
𝟭- 𝗖𝗼𝗻𝗴𝗲𝗻𝗶𝘁𝗮𝗹 𝗮𝗻𝗱 𝗱𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁𝗮𝗹
𝗮𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮 – occurs due to differential growth of the two
eyeballs.
𝟮- 𝗔𝗰𝗾𝘂𝗶𝗿𝗲𝗱 𝗮𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮 – it may occur due to asymmetric
age change, Uniocular Aphakia aftet removal of cataractous lens or due
to implantation of IOL of wrong power.

4. 𝗖𝗟𝗜𝗡𝗜𝗖𝗔𝗟 𝗧𝗬𝗣𝗘𝗦
𝟷- SIMPLE ANISOMETROPIA
𝟸- COMPOᴜND ANISOMETROPIA
𝟹- MIXED ANISOMETROPIA
𝟺- SIMPLE ASTIGMATISM ANISOMETROPIA
𝟻- COMPOᴜND ASTIGMATISM ANISOMETROPIA

5. 𝟭. 𝗦𝗶𝗺𝗽𝗹𝗲 𝗔𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮 –
In this conditions, one eye is normal ( emmetropic) and the other
either myopic ( SIMPLE MYOPIC ANISOMETROPIA) or hypermetropic
( SIMPLE HYPERMETROPIC ANISOMETROPIA) .
𝟮. 𝗖𝗼𝗺𝗽𝗼𝘂𝗻𝗱 𝗔𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮 -
In thiS conditionS, both eyeS are either hypermetropic ( COMPOᴜND
HYPERMETROPIC ANISOMETROPIA) or myopic ( COMPOᴜND MYOPIC
ANISOMETROPIA) , but one eye iS having higher refractive error than
the other.

6. 𝟯. 𝗠𝗶𝘅𝗲𝗱 𝗔𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮 –
In this conditions, one eye is myopic and the other eye is
hypermetropic. ThiS iS called alSo “ 𝘼𝙉𝙏𝙄𝙈𝙀𝙏𝙍𝙊𝙋𝙄𝘼 „ .
𝟰. 𝗦𝗶𝗺𝗽𝗹𝗲 𝗔𝘀𝘁𝗶𝗴𝗺𝗮𝘁𝗶𝘀𝗺 𝗔𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮 –
In this conditions, one eye is normal and the other eye has either
simple myopic or hypermetropic astigmatism.
𝟱. 𝗖𝗼𝗺𝗽𝗼𝘂𝗻𝗱 𝗔𝘀𝘁𝗶𝗴𝗺𝗮𝘁𝗶𝘀𝗺 𝗔𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮 –
In this conditions, both eyes are asthmatic but of unequal degree.

7. 𝗦𝘁𝗮𝘁𝘂𝘀 𝗼𝗳
𝗯𝗶𝗻𝗼𝗰𝘂𝗹𝗮𝗿 𝘃𝗶𝘀𝗶𝗼𝗻 𝗶𝗻
𝗔𝗻𝗶𝘀𝗼𝗺𝗲𝘁𝗿𝗼𝗽𝗶𝗮
𝟭. 𝗕𝗶𝗻𝗼𝗰𝘂𝗹𝗮𝗿 𝘀𝗶𝗻𝗴𝗹𝗲 𝘃𝗶𝘀𝗶𝗼𝗻 - is present in small
degree of
anisometropia ( 𝙡𝙚𝙨𝙨 𝙩𝙝𝙖𝙣 3𝘿 )
𝟮. 𝗨𝗻𝗶𝗼𝗰𝘂𝗹𝗮𝗿 𝘃𝗶𝘀𝗶𝗼𝗻-when refractive error in one eye is of high
degree, that eye is suppressed and develops Anisometropia
Amblyopia thus the pt. Has Only uniocular vision.
𝟯. 𝗔𝗹𝘁𝗲𝗿𝗻𝗮𝘁𝗲 𝘃𝗶𝘀𝗶𝗼𝗻 – one eye is hypermetropic and other
myopic
The hypermetropic eye is used for distant vision and myopic for near
vision.

8. 𝗗𝗜𝗔𝗚𝗡𝗢𝗦𝗜𝗦
1Retinoscopic examination
2Testing for state of binocular vision
a. FRIEND test
b. Worth’S four – dot test

9. 𝗧𝗥𝗘𝗔𝗧𝗠𝗘𝗡𝗧
𝟭. 𝗚𝗹𝗮𝘀𝘀𝗲𝘀
𝟮. 𝗖𝗼𝗻𝘁𝗮𝗰𝘁 𝗹𝗲𝗻𝘀
𝟯. 𝗔𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗰 𝗴𝗹𝗮𝘀𝘀𝗲𝘀
𝟰. 𝗥𝗲𝗳𝗿𝗮𝗰𝘁𝗶𝘃𝗲 𝗰𝗼𝗿𝗻𝗲𝗮𝗹 𝘀𝘂𝗿𝗴𝗲𝗿𝘆
𝟱. 𝗣𝗵𝗮𝗸𝗶𝗰 𝗿𝗲𝗳𝗿𝗮𝗰𝘁𝗶𝘃𝗲 𝗹𝗲𝗻𝘀𝗲𝘀 ( 𝗣𝗥𝗟)
𝟭- 𝗚𝗟𝗔𝗦𝗦𝗘𝗦 – the corrective spectacles can be tolerated up to
a maximum difference of 4D . After that there occur Diplopia.

10. 𝗖𝗼𝗻𝘁𝗮𝗰𝘁 𝗹𝗲𝗻𝘀𝗲𝘀- are advised for higher degree of
anisometropia.
Contact lenses may be very useful in young children with high
anisometropia.
𝗔𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗰 𝗴𝗹𝗮𝘀𝘀𝗲𝘀 – are also available, but their clinical results
Are often disappointing.
𝗥𝗲𝗳𝗿𝗮𝗰𝘁𝗶𝘃𝗲 𝗰𝗼𝗿𝗻𝗲𝗮𝗹 𝘀𝘂𝗿𝗴𝗲𝗿𝘆 - for unilateral high myopia,
astigmatism And hypermetropia.

11. 𝗔𝗡𝗜𝗦𝗘𝗜𝗞𝗢𝗡𝗜𝗔
ANISEIKONIA is defind as a Condition wherein the image projected to
the visual cortex from the two retinae are abnormally unequal size or
shape.
Aniseikonia = Unequal images
ANAMOLY OF BINOCULAR VISION, WHERE OCULAR IMAGES ARE
UNEQUAL IN SIZE OR SHAPE OR BOTH.

12. 𝗘𝘁𝗶𝗼𝗹𝗼𝗴𝗶𝗰𝗮𝗹 𝘁𝘆𝗽𝗲𝘀
𝟭. 𝗢𝗽𝘁𝗶𝗰𝗮𝗹 𝗔𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗮 – May occur due to either inherent Or
acquired anisometropia of high degree.
𝟮. 𝗥𝗲𝘁𝗶𝗻𝗮𝗹 𝗔𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗮 - May develop due to –
• Displacement of retinal elements towards the nodal
point in the one eye and
• Stretching or Oedema of the retina.
𝟯. 𝗖𝗼𝗿𝘁𝗶𝗰𝗮𝗹 𝗔𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗮 -

13. 𝗖𝗟𝗜𝗡𝗜𝗖𝗔𝗟 𝗧𝗬𝗣𝗘𝗦
𝟭. 𝗦𝘆𝗺𝗺𝗲𝘁𝗿𝗶𝗰𝗮𝗹 𝗮𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗮
a.Spherical – image may be magnified or minified equally in both
meridians.
b.Cylindrical – image is magnified or minified symmetrical in one
meridians.
𝟮. 𝗔𝘀𝘆𝗺𝗺𝗲𝘁𝗿𝗶𝗰𝗮𝗹 𝗮𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗮
c.Prismatic . b. Pin- cushion .
c. Barrel distortion .d. Oblique distortion.

14. A. PRISMATIC – difference increases progressively in one direction
B. PIN- CUSHION – distortion increases progressively in both direction
C. BARREL DISTORTION – distortion decrease progressively in both
direction as seen with high (-) correction.
Oblique DISTORTION –the size of image is same but there occurs an
oblique distortion of shape.

15. 𝗧𝘆𝗽𝗲𝘀 𝗼𝗳
𝗔𝗻𝗶𝘀𝗲𝗶𝗸𝗼𝗻𝗶𝗮

16. 𝗦𝘆𝗺𝗽𝘁𝗼𝗺𝘀
Asthenopia – eyeache browache and tiredness of eyes.
Diplopia - due to difficult binocular vision when the difference in
Images of two eyes is more than 5% .
Difficulty in depth perception is often noticed.

17. 𝗧𝗥𝗘𝗔𝗧𝗠𝗘𝗡𝗧
• 1 optical - Aniseikonia may be corrected by aniseikonic glasses,
Contact lenses, Intraocular lenses or other refractive
Surgery depending upon the situation.
• 2 Retinal Aniseikonia may be corrected by treating the cause.
• 3 Cortical Aniseikonia is very difficult to treat.