Luxation postérieure bilatérale spontanée du cristallin

We report the case of an 89-year old female patient with a history of high blood pressure without ocular trauma. Ophthalmological examination showed bilateral visual acuity of counting fingers. Bilaterally, biomicroscopy found clear cornea, good anterior chamber, exfoliation material deposit at the edge of the pupil. In the left eye, crystalline lens was posteriorly subluxated but still visible in the pupillary area (A). Right eye fundus examination revealed dislocation of the crystalline lens into the vitreous (B). The diagnosis of spontaneous bilateral dislocation of the crystalline lens secondary to pseudoexfoliation syndrome was established. Data from the literature highlight that pseudoexfoliation syndrome is an age-related systemic disease associated with elastic microfibrillopathy due to altered LOXL1 gene. This results in the production and accumulation of fibrillar deposits within the extracellular matrix of several organs. This syndrome is most often bilateral and asymmetric. Clinical manifestations include cataract, glaucoma, bad pupillary dilatation, phacodonesis or spontaneous subluxation of the crystalline lens into the vitreous due to zonular instability. It has been reported in the literature that this zonular instability may be due to disruption secondary to the deposit of fibrillary material at the pre-equatorial zonule insertion. Other studies have reported that this may be intrinsic, given that, in affected eyes, zonular fiber examination shows differences in elastic fibers with respect to unaffected eyes.

Key words: Pseudoexfoliation syndrome, elastic microfibrillopathy, zonular instability, crystalline lens dislocation