Optical coherence tomography and optical coherence tomography angiography imaging in Bietti crystalline dystrophy.

Background: Bietti crystalline dystrophy (BCD) is a rare autosomal recessive disorder due to genetic defect in the CYP4V2 gene. BCD is a disease characterized by shiny yellow crystalline deposits in the retina with progressive atrophy of the retinal pigment epithelium and choriocapillaris. Our aim is to present ocular imaging findings of a patient with BCD.Materials and Metods: A 38-year-old female patient with BCD was evaluated and the findings of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) were examined.

Results: OCT imaging revealed multiple outer retinal tubulations (ORTs) with a few hyperreflective crystalline deposits. OCTA imaging showed that the vessel density of superficial anddeep capillary plexus and choriocapillaris blood flow were significantly decreased. ORTs were composedof multiple microtubules as finger-like protrusions that joined the macrotubules.

Conclusion: In BCD, crystallinedeposits, ORTs and retinal vascular morphology can be shown in detail using OCT and OCTA.