Abstract:
White dot syndromes are classified on the basis of clinical signs, as well as clinical and angiographic evolution. So far, there is little histopathological correlation available in either active or quiescent stages of these diseases. With the help of an en–face OCT, "optical biopsies" were taken and analysed in patients with multifocal (MFC) and serpiginous choroiditis (SC).
Twelve patients with a diagnosis of MFC, and 4 patients with SC underwent ophthalmologic examination and fundus photography. Patient demographics, treatment, disease duration, and fundoscopic findings were recorded. Each patient was scanned with a prototype OCT Ophthalmoscope in both longitudinal and transversal directions (OCT B– and C–scans). Representative areas on the fundus photographs were selected and compared with the OCT findings. These were analysed for retinal integrity (thickness and structure), appearance of the RPE, and of the choroid.
One MFC and one SC patient had an active lesion at the time of scanning. On both OCT B– and C–scans, the active MFC lesion was imaged as a lesion with increased retinal reflectivity in all layers, with loss of retinal structure. Retinal thickness was unchanged. In the active SC lesion, increased reflectivity was only seen in the outer retina. Chronic MFC lesions were characterized by retinal atrophy, loss of retinal integrity, and pigment migration into the retina. Chronic lesions in SC showed more RPE irregularities. Retinal atrophy was only noted in large lesions, while the inner retina was often preserved in smaller SC lesions.
The OCT allows for the distinction of retinal pathological processes during both the active and scarred stages of disease. These findings seem to relate to particular disease entities, but also to severity.
Keywords: imaging/image analysis: clinical • chorioretinitis • retinochoroiditis