Expanded spectrum of focal scleral nodule: focal scleral nodules can be bifocal

Abstract

Background: To assess multimodal imaging findings of focal scleral nodule (FSN) to evaluate its origin and natural course.

Methods: This was a retrospective observational case series and included 14 patients with FSN who underwent multimodal imaging. Clinical information was gathered from patients' medical records. Primary outcome measures were standardized grading of imaging features.

Results: The mean follow-up duration was 68.8 ± 43.6 months (range, 6-139 months). Most lesions were solitary (92.6%), but one patient had two adjacent lesions (7.1%). Optical coherence tomography revealed that all lesions were confined to the sclera. Lesions showed mostly outer retinal abnormality, with external limiting membrane thinning or absence in 41.6% of lesions and ellipsoid layer absence in 84.6% of lesions. Most lesions showed an absence (69.2%) or thinning (23.1%) of the choroid above the lesion, and the mean choroidal thickness above the lesion for choroids with measurable thickness was 36 ± 75 μm (median, 0; range, 0-265 μm). Of 13 lesions with available follow-up data, only three lesions showed minimal growth over time.

Conclusions: This study demonstrates for the first time that bifocal lesions of FSN in the same eye are possible and reaffirms the relative stability of this entity.