This 42YO female has been followed by us for 7 years with a known history of Bietti crystalline retinopathy with homozygosity for a pathogenic CYP4V2 variant. Vision was stable at 20/400 OU.
Fundus imaging shows extensive pigmentary degeneration with subretinal crystalline deposits involving both posterior poles. The crystalline deposits are best seen on near-infrared imaging. OCT scanning shows hyperreflective dots overlying the RPE-Bruch’s membrane complex with variable outer retinal and RPE loss. The pigmentary changes extend into each retinal periphery with more typical retinitis pigmentosa-like changes, including intraretinal pigment migration (bone spicules).
Learning Points:
Bietti crystalline dystrophy is an autosomal recessive ocular disorder that affects both the anterior and posterior segments. Clinical features include crystalline deposits in the retina, cornea, and rarely the crystalline lens, as well as retinal pigment epithelial clumping and atrophy. Mutations in CYP4V2 causing dysfunctional lipid metabolism have been implicated in its pathogenesis. While there are no definite treatments, anti-VEGF therapy can be given for secondary macular neovascularization. See Saatci et al for a recent review (Clinical Ophthalmology 2023;17:953-967).
