Novel method of detection of birefringent ocular amyloidosis deposits using monochromatic wavelengths of scanning laser ophthalmoscopy.

Purpose: To describe a noninvasive imaging technique for detection of ocular amyloidosis using ultrawide field (UWF) images.

Methods: This was a retrospective, case-control study of patients with familial transthyretin (TTR) amyloidosis seen at the Wills Eye Hospital, USA and Moorfields Eye Hospital, UK. Pseudocolor, 100% red and 100% green UWF fundus images of patients with familial TTR were reviewed and, sensitivity, specificity and area under the curve (AUC) for the pattern abnormalities noted on fundus images for amyloidosis were calculated.

Results: A total of 19 eyes of 10 patients with TTR amyloidosis were included. Vitreous floaters were the most common posterior segment manifestation present in 57.9% (N=11/19) eyes. The sensitivity and specificity for a hypointense or isointense pattern on 100% red and a hyperintense pattern on 100% green being amyloidosis was 57.9% (95% Cl: 33.5%-79.7%) and 100% (95% CI: 54.1%-100%) respectively. The AUC was 0.79 (95% CI: 0.68-0.90). Excluding the hypomorphic V122I mutation, the sensitivity and specificity for a hypointense or isointense pattern on 100% red and a hyperintense pattern on 100% green being amyloidosis was 64.7% (95% CI: 38.3%-85.8%) and 100% (54.1%-100%) respectively. The AUC was 0.82 (95% CI: 0.71-0.94). Histopathological analysis showed amyloid deposits were visible under green and blue filters but were not visible under the red filters.

Conclusion: The appearance of amyloid deposits can vary based on the type of scanning laser used. The methodology described here represents a novel and noninvasive approach to detect ocular amyloidosis with relatively high specificity.