Background: Coats disease presents a diagnostic challenge due to its diverse clinical manifestations, which can mimic retinoblastoma. Severe vision loss and potential enucleation are late consequences of the disease. In this study, we provide an analysis of the main histopathological findings in enucleated eyes affected by Coats disease, supplemented with a review of the existing literature.

Methods: A retrospective analysis was conducted on all enucleated globes diagnosed with Coats disease over a 30-year period. Two pathologists reviewed the specimens, while collecting corresponding demographic data, clinical presentation, pre-operative clinical impressions, and indications for enucleation. Descriptive analysis was performed on our own series data, which was subsequently compared with relevant literature published in English between 1983 and 2021, obtained from the PUBMED database. The inclusion criterion for the analyzed published reports was the utilization of the Shields classification.

Results: We identified seven enucleated globes affected by Coats disease. The mean age at presentation was 3.2 years (range: 3 months to 9 years). The majority of cases were unilateral (100%) and exhibited a male predominance (86%). Strabismus was the most frequent initial presentation (57%), followed by leukocoria (43%). Suspected retinoblastoma was the primary indication for enucleation in most cases (57%). Four eyes were classified as stage 4, while two demonstrated advanced stage 5 changes. Histopathological analysis revealed the presence of subretinal fluid with lipid-laden macrophages in all cases. Shallow anterior chambers were observed in 5 out of 7 cases, with angle neovascularization noted in 2 cases. Telangiectatic vessels were clearly observed in 4 cases.

Conclusion: Coats disease is a visually debilitating condition that predominantly affects one eye in 95% of cases, with a male predominance of 81%. The age range varies widely, with a mean age of 17 years. In Saudi Arabia, the disease appears to manifest at a younger age, presents at more advanced stages, and can be challenging to differentiate from retinoblastoma at the time of diagnosis. Following the Shields staging system for Coats disease is highly recommended to guide treatment decisions and establish consistent outcomes.