What does retroillumination primarily help detect?

Retroillumination is a technique used in ophthalmology that involves shining light onto the eye, allowing the observer to assess various structures within the eye based on how the light interacts with them. This method is particularly effective at revealing changes or abnormalities in the lens. When light passes through the lens, any opacities or defects present can scatter the light, making them visible during examination. This makes retroillumination a valuable tool for detecting cataracts or other lens-related issues, as these conditions can lead to changes in transparency within the lens that might not be apparent through direct examination alone.

In contrast, while other conditions related to eye health may be important, retroillumination is not specifically designed to assess corneal curvature changes, measure intraocular pressure, or evaluate conjunctival infections. Each of those conditions typically requires different examination techniques or tools, making retroillumination specifically relevant for identifying lens opacities and defects.