A comparative study of spectral domain optical coherence tomography (SD-OCT) showing presence and characteristics of intraretinal hyperreflective foci in patients of normolipemic xanthelasma palpebrarum as compared to healthy subjects

Abstract

Background and Objectives: Hyperreflective foci (HRF) are a morphological sign of accumulation of lipid extravasation, proteinaceous material, and inflammatory cells in the layers of retina. The purpose of this study is to determine the presence, location, and characteristics of hyperreflective foci in the retina of normolipemic patients with xanthelasma palpebrarum. Methods: A total of 50 test subjects with xanthelasma were evaluated and compared with 50 control subjects. SD-OCT was performed in all patients passing through the center of fovea. On OCT, presence and absence of hyperreflective foci were noted. Following characteristics of the hyperreflective spots were evaluated and compared: location (inner retina or outer retina), shape, size, and back shadowing. Results: Hyperreflective foci were present in 87 out of 100 eyes of test subjects (87%) and none in control group (P-value < 0.001, significant). Shape of hyperreflective foci was predominantly round (54.2%), and location of hyperreflective foci was predominantly in outer nuclear and outer plexiform layer (30.1%). Back shadowing was present with frequency of 58 (80.6%). Conclusion: Hyperreflective foci are a great indicator for lipid extravasation and have been significantly associated with patients of xanthelasma having normal lipid levels. This signifies a defect in vascular integrity in patients of xanthelasma with normal lipid levels. Hence, these patients are at increased risk of atherosclerotic plaque formation and systemic complications.