Abstract
Abstract: :
Purpose: To describe the clinical, FA, OCT, ERG, and mERG findings of Bietti’s Crystalline Dystrophy (BCD) in a 31 year old male and his 37 year old sister. Methods: An OCT, ERG, mERG, FA and clinical exam were performed in two patients diagnosed with BCD. Results: The FA demonstrated distinct areas of hypofluorescence, interspaced within a more confluent background of mottled hyperfluorescence throughout the posterior pole. The fundus findings suggested a generalized atrophy of the RPE, with minimal sparing of the central fovea. The ERG showed subnormal a and b waves (2/3 normal) with a normal implicit time in response to scotopic and photopic stimuli. The oscillatory potentials were elicited but reduced. The responses were symmetric. The mERG showed a severe and diffuse decrease in amplitude of the first and second order Kernels while the implicit times showed minimal to no delay. OCT revealed a normal vitreoretinal interface. The retina demonstrated normal thickness with a physiologic foveal depression; no abnormal signal was detected within the retinal layers. The RPE and choriocapillaris layers were thickened bilaterally with contour irregularities. There was shadowing deep to this layer corresponding to intraepithelial deposits. Clinical examination demonstrated abnormal crystalline material within the tear film, conjunctiva and peripheral cornea as well as the retina (Figure 1). Visual acuity was reduced in one of two patients. Conclusion: To our knowledge this is the first report of the OCT and mERG in a patient with BCD. The mERG results demonstrate the focal nature of BCD in a young person while the OCT findings confirm the location of the crystalline deposits within the RPE and choriocapillaris. The identification of crystalline material within the tear film of patients with BCD has not previously been reported. Figure 1. Fundus photograph of male patient with BCD
Keywords: 554 retina • 432 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 395 electroretinography: clinical