Which sign is described as lens dance (phacodenesis)?

• A. Phacodenesis (lens dance)
• B. Aphakia
• C. Iris atrophy
• D. Cataract

Answer: (A)

Phacodonesis is the tremulous movement of the crystalline lens caused by lax or damaged zonules. The sign described as lens dance directly refers to this phenomenon, where the lens visibly wobbles or “dances” with eye movements. This indicates zonular weakness or lens subluxation, as seen in conditions like trauma or connective-tissue disorders such as Marfan syndrome or homocystinuria. In contrast, aphakia means there is no lens at all, iris atrophy is degeneration of the iris tissue, and cataract is clouding of the lens—none of these describe a moving lens. So the lens dance sign is phacodonesis.