Shifting crystalline pseudohypopyon secondary to lens absorption with spontaneous openings in the anterior lens capsule.

This is the first reported case of a crystalline pseudohypopyon presenting as a layer of "snowdrift deposits" that settled inferiorly in the anterior chamber of the eye of a 55-year-old man and was associated with freely floating crystals in the aqueous humor, producing a "snowy Christmas Eve" appearance. The cause was spontaneous openings in the center of the anterior capsule with leaching of the crystalline substance into the anterior chamber. A dense membranous cataract was left after the lens material was partly absorbed. There was no history of trauma, surgery, or known systemic disease, and the patient presented with a unilateral, mobile, 4.0 mm white pseudohypopyon with no global pain, photophobia, or lacrimation. Although the eye was not injected on admission, repetitive head shaking resulted in dusky-red perilimbal hyperemia. A B-mode ultrasound revealed an advanced retinal detachment, and electroretinographic recordings were undetectable. Visual acuity decreased to hand motions in the affected eye, and the patient ultimately required anterior chamber paracentesis. Such sediments should be differentiated from other forms of true or pseudohypopyons because the course, treatment, and prognosis are different for each.