Assessment of hyperreflective foci using multimodal imaging in eyes with age-related macular degeneration

Abstract

Purpose : Hyperreflective foci (HRF) on optical coherence tomography (OCT) appear to be one of the strongest risk factors for the progression of age-related macular degeneration (AMD). The purpose of the study is to assess the multimodal imaging characteristics of these lesions by comparing HRF identified on OCT B-scans with pigmentation on color fundus photographs (CFP) and hyperreflectivity on infrared reflectance (IR) images in eyes with AMD.

Methods : A total of 117 eyes from 75 patients with intermediate AMD and HRF enrolled in the Amish Eye Study were evaluated in this retrospective analysis. Flash CFP, IR images, and OCT B-scans (Heidelberg Spectralis) obtained at the same visit were evaluated by trained reading center graders. Individual HRF identified on OCT B-scans were assessed for the qualitative presence or absence of hypotransmission tail into choroid. The corresponding IR image obtained at the time of OCT acquisition was analyzed for the presence or absence of hyperreflectivity in this region. The IR images were manually registered to the CFP image, and CFP images were inspected for the presence or absence of pigmentation at the location of HRF.

Results : A total of 494 HRF were evaluated in this analysis. For the primary analysis of qualitative presence or absence of pigmentation on CFP and hyperreflectivity on IR and locations corresponding to HRF on OCT, 301 (61.0%) of the HRFs demonstrated evidence of pigmentation on CFP, while only 115 (23.3%) showed evidence of hyperreflectivity on IR. The qualitative determination of the presence or absence of an abnormality on CFP or IR were significantly different (p <0.0001). 327 (66.2%) of the HRF showed evidence of shadowing or hypotransmission, and 80.4% of these HRF showed pigmentation on CFP, though only 23.9% (p <0.0001) demonstrated hyperreflectivity on IR. Inter-grader reproducibility revealed a high degree of agreement with Cohen’s κ= 0.97 for hyperreflectivity on IR and κ= 0.96 for pigmentation on CFP.

Conclusions : Less than two-thirds of HRF evident on OCT manifest as hyperpigmentation on color photos, though HRF with posterior shadowing are more likely to be evident as pigment. IR imaging appears to be even more poorly sensitive for visualizing HRF. These findings may be of value in the design of imaging acquisition and analysis protocols in studies of AMD.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.