An accidental diagnosis of optic nerve meningioma in a patient affected by thyroid eye disease

A 42-year-old woman presented to our hospital owing to a history of right-sided proptosis of 4 months duration, reporting no previous trauma, fever, or recent sinusitis. Her medical record included a diagnosis of Graves’ disease. The best corrected visual acuity (BCVA) was 20/20 and a 30.2 visual field test was normal. A 3-Tesla magnetic resonance imaging (MRI) revealed an orbital apex meningioma approaching the walls of the sulcus chiasmaticus. A subsequent 60.4 perimetry test showed bilateral nasal visual field defects, thus confirming the involvement of the optic nerve. The reported case focuses on the differential diagnosis with Thyroid Eye Disease (TED) and the subsequent follow-up.