Hyperreflective pyramidal structures on optical coherence tomography in geographic atrophy areas.

Abstract

We observed hyperreflective dome-shaped or pyramidal structures (HPS) on spectral domain optical coherence tomography (SD-OCT) in patients affected with geographic atrophy (GA). Our purpose was to describe the multimodal imaging features of HPS identified in areas of GA in patients with age-related macular degeneration. This is a retrospective case series of patients with GA harboring HPS in atrophic areas. Multimodal imaging examination including infrared reflectance, fundus autofluorescence, and SD-OCT, was performed for each patient. Infrared and fundus autofluorescence appearance and mean SD-OCT height of HPS in GA were analyzed. A total of 36 eyes of 25 patients (20 women; mean age, 82.3 ± 5.9 years, range, 73-92 years) with GA were included. A total of 96 HPS in GA were analyzed by SD-OCT. In all HPS (96/96, 100%), the peripheral part was hyperreflective. In 66 of 96 HPS (69%), the center was heterogeneously hyperreflective, whereas in 30 of 96 HPS (31%), the center was hyporeflective. On infrared reflectance images, HPS in GA appeared as hyporeflective lesions surrounded by hyperreflective halos, within an area of background hyperreflectivity because of GA in all eyes. On fundus autofluorescence, 39 of 96 HPS (41%) were heterogeneously hyperautofluorescent, whereas 57 of 96 HPS (59%) were hypoautofluorescent. Mean height of HPS was 91 ± 50.9 μm in the foveal scan (range, 42-291 μm). We describe a multimodal imaging of distinctive lesions that presented as hyperreflective pyramidal structures on SD-OCT. We suggest the name "ghost drusen" because these HPS appear in GA areas, and because of their pyramidal or dome-shaped aspect on SD-OCT.