Fluorescence lifetime imaging ophthalmoscopy (FLIO) in punctate inner choroidopathy and multifocal choroiditis with panuveitis

Abstract

Purpose : To investigate patterns seen in fluorescence lifetime imaging ophthalmoscopy (FLIO) as an adjunct multimodal imaging modality in patients with punctate inner choroidopathy (PIC) and multifocal choroiditis with panuveitis (MCP), two varieties of idiopathic inflammatory posterior uveitis.

Methods : Fifteen patients with PIC/MCP underwent multimodal imaging in this clinic-based, cross-sectional study. All patients received Heidelberg Engineering FLIO measurements. Fundus autofluorescence (FAF) lifetimes of a 30° retinal field were detected in short (498-560 nm, SSC) and long (560-720 nm, LSC) spectral channels. Amplitude-weighted mean fluorescence lifetimes (t_m) were calculated. FAF intensity images and optical coherence tomography (OCT) scans were also compared with FAF lifetime patterns.

Results : In this preliminary cohort, FAF lifetimes are prolonged in the SSC in areas corresponding to classic PIC/MCP chorioretinal spots identified in FAF intensity images. Smaller spots are readily identifiable in the LSC, where they also demonstrate some heterogeneity; some have focally shorter FAF lifetimes whereas others show prolonged FAF lifetimes. Long FAF lifetimes (>350 ps, LSC) are found in larger areas of scarring due to inactive choroidal neovascularization, which is an often-noted sequela of PIC and MCP. In some patients, a border of shorter FAF lifetimes appears to extend beyond the disease area delineated by FAF intensity images, which has been correlated to atrophy in other uveitis studies and thus might be suggestive of more extensive pathology.

Conclusions : This study explores FAF lifetime patterns for PIC and MCP using FLIO. As these disease processes are rare and can be challenging to diagnose and monitor for disease progression, FLIO represents an emerging imaging modality that may contribute additional insight regarding disease activity. Further studies including longitudinal data are needed to better characterize the potential impact of these findings.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

Fundus autofluorescence intensity and lifetime images from long spectral channel (560 - 720 nm) for two patients (A) and (B) with punctate inner choroidopathy.