Phacodonesis is best described as which of the following?

• A. Iridodonesis
• B. Endophthalmitis
• C. Pupil dilation
• D. Wobble or tremulousness of the lens due to zonular laxity

Answer: (D)

Phacodonesis describes wobble or tremulousness of the lens itself caused by lax or damaged zonules. When the eye moves, a loosened suspensory system lets the lens tilt or shift, producing visible tremor of the lens during examination. This is different from iridodonesis, which is a tremor of the iris that can occur when the lens support is compromised or absent, rather than the lens moving. Endophthalmitis is an intraocular infection with symptoms like pain, redness, and vision loss, not a mechanical tremor of the lens. Pupil dilation refers to enlargement of the pupil, not movement or tremor of the lens. Recognizing phacodonesis highlights zonular weakness or subluxation scenarios (such as trauma or conditions like Marfan syndrome), and alerts to potential lens instability and challenges in intraocular procedures.