|Title||NEW INSIGHTS INTO MORPHOLOGIC CHARACTERISTICS OF DIFFERENT TYPES OF DRUSEN AS REVEALED BY SD-OCT|
|Author, Co-Author||Elena Zaharova, Jerome Sherman|
|Abstract|| PURPOSE: To identify the unique reflective characteristics of cuticular hard drusen, infiltrative hard drusen, subretinal drusenoid deposits, soft drusen and geographic atrophy using Spectral Domain Optical Coherence Tomography (SD-OCT) imaging technology and retinal layer-by-layer analysis.
METHODS: A retrospective review of 1200 images performed with SD-OCT (Topcon, 3DOCT-2000, Oakland, NJ, USA) at SUNY State College of Optometry. A total of 52 scans containing drusen were identified. The following morphologic characteristics were evaluated: integrity of the retinal pigment epithelium (RPE) and the photoreceptor integrity line (PIL) layers, location of drusenoid deposits and associated visual function.
RESULTS: Cuticular hard drusen appear as discrete dome-shaped elevations of RPE layer due to the deposits external to the RPE basement membrane. The distinguishing feature is the presence of attenuated PIL on top of the cuticular deposits. Infiltrative hard drusen appear as multiple discrete deposits that infiltrate through the RPE and PIL with disruption of both layers. Subretinal drusenoid deposits are localized between the RPE and the PIL layers with the presence of intact PIL and the RPE layers. Soft drusen have a classical pigment epithelium detachment (PED)-like appearance with less reflective material inside. The largely elevated drusen are typically associated with a compromised PIL and enhanced visibility of Bruch’s membrane. Geographical atrophy appears to have missing PIL and the RPE layers, along with the easily visualized Bruch’s membrane. The integrity of the PIL is associated with visual function as revealed by Fundus Autofluorescence and macular integrity assessment (Centervue, MAIA, Santa Clara, CA, USA).
CONCLUSIONS: Although different types of drusen are composed of similar components, they can be distinguished by careful layer-by-layer analysis of SD-OCT imaging. Morphologic differences between the distinct subclasses of drusen may be useful imaging biomarkers for assessing disease severity.
|Affiliation of Co-Authors||State University of New York, College of Optometry|