Prevalence of peripheral abnormalities on ultra-widefield greenlight (532 nm) autofluorescence imaging at a tertiary care center

Abstract

Purpose: To assess the prevalence of peripheral fundus autofluorescence (FAF) abnormalities in a variety of diseases seen at a tertiary retina clinic.

Methods: We conducted a retrospective review of cases seen at the Doheny Eye Institute between November 2009 and May 2011, who had ultra-widefield FAF and pseudocolor imaging performed on new models of scanning laser ophthalmoscopes. Patients with a history of previous therapies that could alter the FAF findings, including vitrectomy, cryotherapy, laser photocoagulation, or photodynamic therapy, were excluded from the analysis. Based on their primary diagnosis the eyes were grouped into nine disease categories: age-related macular degeneration, central serous retinopathy, dystrophy, inflammatory disorders, ocular tumor, retinal vascular disorders, other, normal, and unknown. All FAF and accompanying pseudocolor images were reviewed independently by two reading center-certified graders.

Results: A total of 470 eyes of 248 patients were included for analysis of which 461 eyes had images of sufficient quality for grading. The prevalence of peripheral findings was 65.5% (n = 302) for FAF images and 68.5% (n = 316) for the pseudocolor images (P < 0.001). The prevalence of peripheral abnormalities differed significantly between the disease categories ranging from 18.5% to 82.2% for FAF and 18.5% to 82.4% for pseudocolor images.

Conclusions: Peripheral FAF abnormalities are frequent and readily revealed by FAF imaging. Interestingly, even cases with presumably macular disease demonstrated a high prevalence of peripheral findings. Further investigation in prospective studies is warranted.

Figure 1.

FAF (A) and corresponding pseudocolor image (B) of a case with atypical acute multifocal placoid pigment epitheliopathy. The FAF image is schematically sectioned to illustrate the grading process. Abnormalities outside the central FOV (labeled as Fields 1M + 2) were graded according to their location in either the superior, temporal, inferior, or nasal quadrant. Of note, the peripheral changes correlate well between FAF and pseudocolor in this case.

Figure 2.

Images (A) and (B) show a case with AMD that appears to have almost no peripheral abnormalities on FAF (B), but the abnormalities seem more evident in the pseudocolor image (A). Contrarily, (C) and (D) show a case with a retinal dystrophy. The pseudocolor image (C) does not suggest noticeable peripheral abnormalities. However, they become more clear on the FAF image (D).