Focal Scleral Nodules: Retrospective Case Series and Novel Insight.

Purpose: The objective of this study was to add to the limited literature of Focal Scleral Nodule (FSN).

Methods: This study was a single-centre, retrospective, observational case series performed at Manchester Royal Eye Hospital (United Kingdom). Nineteen eyes from nineteen patients over a thirteen year period (January 2011 to January 2024) were included. The principal observations were taken from patient demographic data, fundal and autofluorescence imaging, and OCT-EDI imaging.

Results: Most patients with FSN were female, with median age of 47 years and median visual acuity of 20/20 Snellen. FSN were yellow, yellow-white, orange or orange halo in appearance. Median horizontal length of a FSN was 2.02mm (range 0.34mm-4.79mm) and median thickness was 417μm (range 272μm-803μm). The choroid above the FSN was thinned in 9 and absent in 10 cases. Most FSN appeared hyper-autofluorescent on autofluorescence imaging. Extramacular FSN appeared directly inferiorly to the optic disc in 7, infero-temporally in 5, supero-nasally in 2, and supero-temporally in 5 cases. Seven patients demonstrated FSN within the macula, and 2 of these had subretinal fluid. Further investigation revealed one of these patients with subretinal fluid had polypoidal choroidal vasculopathy (PCV) at the same area as the FSN.

Conclusion: This study analysed FSN lesions of a medium-sized group over a large timeframe. It provides more data in the literature for an uncommon ophthalmic lesion. Furthermore, the study described the first known case in the literature of FSN with PCV in the same area. This finding highlights a potential new complication of the condition.