Cataract

Cortical senile cataract. Its main biochemical features are decreased levels of total proteins, amino acids and potassium associated with increased concentration of sodium and marked hydration of the lens, followed by coagulation of proteins. The probable course of events leading to senile opacification of cortex

Clinical features Symptoms. An opacity of the lens may be present without causing any symptoms; and may be discovered on routine ocular examination.

Common symptoms of cataract are as follows: 1. Glare. One of the earliest visual disturbances with the cataract is glare or intolerance of bright light; such as direct sunlight. Early nuclear senile cataract. an oncoming motor vehicle. The amount of glare or dazzle will vary with the location and size of the opacity.

1. Uniocular polyopia (i.e., doubling or trebling of objects): It is also one of the early symptoms. It occurs due to irregular refraction by the lens owing to variable refractive index as a result of cataractous process.
2. Coloured halos. These may be perceived by some patients owing to breaking of white light into coloured spectrum due to presence of water droplets in the lens.
3. Black spots in front of eyes. Stationary black spots may be perceived by some patients.
4. Image blur, distortion of images and misty vision may occur in early stages of cataract.
5. Loss of vision. Visual deterioration due to senile cataract has some typical features. It is painless and gradually progressive in nature