in nuclear cataract since there is un- opacified cotrex between the lens and the iris then there should be formation of iris shadow but why in reality it doesn’t form iris shadow?
In nuclear cataract, the opacification occurs primarily in the central portion (nucleus) of the lens, which is located behind the iris. The opacification in this area can cause the lens to become yellow or brown, leading to reduced transparency and visual impairment.
While the opacification affects the central part of the lens, it does not necessarily result in the formation of an iris shadow. The reason for this is the way light is transmitted through the eye and the way the opacified lens interacts with incoming light.
When light enters the eye, it passes through the cornea, pupil, and then the lens before reaching the retina at the back of the eye. In a normal eye, the lens is transparent, allowing light to pass through it unimpeded. However, in nuclear cataract, the opacification of the central part of the lens can scatter or block some of the incoming light.
The scattering or blocking of light by the opacified lens prevents a clear image from forming on the retina. As a result, the individual may experience blurred vision or difficulty seeing clearly. However, since the opacification is occurring within the lens itself and not in the space between the lens and the iris, it does not typically produce a distinct shadow of the iris.
It’s important to note that the specific characteristics and effects of cataracts can vary among individuals. The absence of an iris shadow in nuclear cataract is a general observation, but individual variations may exist. If you have specific concerns about your eye health or vision, it is recommended to consult with an ophthalmologist for a comprehensive evaluation and personalized advice.