EC Ophthalmology

Purpose: To describe a case of bilateral optic pathway gliomas (OPG) in a pediatric patient with neurofibromatosis type 1 (NF1), highlighting multimodal ophthalmic findings, radiologic correlation, and considerations for clinical management.

Case Presentation: A 4-year-old girl with recently diagnosed NF1 was referred for ophthalmologic evaluation. Best-corrected visual acuity (BCVA) was 20/40 in both eyes. Pupils were symmetric without relative afferent pupillary defect. Anterior segment examination revealed Lisch nodules, and dilated fundus evaluation showed mild bilateral optic disc pallor. Optical coherence tomography (OCT) demonstrated sectoral thinning of the circumpapillary retinal nerve fiber layer (RNFL), predominantly temporally and nasally. Due to progressive BCVA decline in subsequent visits and structural worsening on OCT, brain and orbital MRI were obtained, revealing fusiform enlargement of both optic nerves extending toward the chiasm, consistent with bilateral optic pathway gliomas. Given progressive visual involvement, the patient was referred to pediatric oncology and treated with weekly vinblastine.

Conclusion: Bilateral OPGs are a recognized manifestation of NF1. Progressive visual decline and OCT/RNFL thinning should prompt neuroimaging and multidisciplinary evaluation. Early recognition and monitoring are crucial to prevent irreversible vision loss.

 Keywords: Neurofibromatosis Type 1; Optic Pathway Glioma; Pediatric Neuro-Oncology; Retinal Nerve Fiber Layer; Lisch nodules

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