Senile cataract- forms, stages and treatment. Aphakia.
Cataract refers to the development of any opacity in the lens of the eye, or its capsule; which therefore leads to a decrease in vision. Senile cataract is also referred to as ‘age related cataract’ as it affects people above 50 years of age. One eye is usually affected first, followed by the other eye.
There are two types of senile cataract:
1-Cortical (soft) cataract
2-Nuclear (hard) cataract
Stages:
- Stage of lamellar separation. The earliest senile change is demarcation of cortical fibres owing to their separation by fluid. These changes are reversible.
- Stage of incipient cataract. In this stage early detectable opacities with clear areas between them are seen. Two distinct types of senile cortical cataracts can be recognised at this stage: (a) Cuneiform senile cortical cataract. It is characterised by wedge-shaped opacities with clear areas in between. Since the cuneiform cataract starts at periphery and extends centrally, the visual disturbances are noted at a comparatively late stage. (b) Cupuliform senile cortical cataract. Here a saucer-shaped opacity develops just below the capsule usually in the central part of posterior cortex (posterior subcapsular cataract), which gradually extends outwards.
- Immature senile cataract (ISC). In this stage, opacification progresses further. The cuneiform or cupuliform patterns can be recognised till the advanced stage of ISC when opacification becomes more diffuse and irregular. The lens appears greyish white but clear cortex is still present and so iris shadow is visible.
- Mature senile cataract (MSC). In this stage, opacification becomes complete, i.e., whole of the cortex is involved. Lens becomes pearly white in colour.
- Hypermature senile cataract (HMSC). When the mature cataract is left in situ, the stage of hypermaturity sets in. The hypermature cataract may occur in any of the two forms:
- (a) Morgagnian hypermature cataract: In some patients, after maturity the whole cortex liquefies and the lens is converted into a bag of milky fluid. The small brownish nucleus settles at the bottom, altering its position with change in the position of the head.
- (b) Sclerotic type hypermature cataract: Sometimes after the stage of maturity, the cortex becomes disintegrated and the lens becomes shrunken due to leakage of water. The anterior capsule is wrinkled and thickened due to proliferation of anterior cells and a dense white capsular cataract may be formed in the pupillary area.
Treatment: