Visual field loss in Sturge–Weber syndrome and phakomatosis pigmentovascularis: Implications for glaucoma assessment

Objectives: To evaluate the patterns of visual field (VF) defects in patients with Sturge–Weber syndrome (SWS) and phakomatosis pigmentovascularis (PPV) using standard automated perimetry. Methods: This retrospective study analyzed the clinical and VF data of patients with SWS or PPV undergoing treatment for glaucoma and had VF test data over a 27-year period. VF defects were classified as glaucomatous, neurological, combined, or unclassifiable. Statistical analyses were performed to determine factors associated with type of field defects. Results: A total of 86 patients (172 eyes) were included, with 62 (72%) having SWS and 24 (28%) PPV. Glaucoma was present in 49.2% of SWS eyes and 91.6% of PPV eyes. Reliable VF tests were more common in SWS than in PPV ( P < 0.001). Glaucomatous defects were observed in 35.5% of eyes, 7.7% had neurological defects, and 4.1% had combined defects. Advanced field loss was the most common glaucomatous defect (54%). Eyes treated with external beam radiotherapy for diffuse choroidal hemangioma developed localized field defects mimicking glaucoma and homonymous hemianopia. Conclusions: Glaucoma remains the primary cause of VF loss in SWS and PPV, with a significant proportion of patients demonstrating advanced glaucomatous damage. Accurate interpretation of VF results is crucial for differentiating glaucomatous progression from other ocular and neurological causes in these rare phakomatoses.