The authors discuss the difficult clinical scenario of patients with deteriorating visual function and an optic pathway lesion. The morbidity associated with biopsy means a highly sensitive and specific imaging technique would be of great value. The authors describe the use of combined Ga-68-DOTA-TATE PET and CT to diagnose optic pathway meningiomas. The imaging technique relies on the expression of somatostatin receptors by meningiomas. The imaging technique was used to examine 13 patients with ambiguous, symptomatic optic pathway lesions. The results of the imaging were validated by histopathology in five patients and conventional clinical / radiological examination in the others. The authors conclude that Ga-68-DOTA-TATE PET/CT is a sensitive and specific imaging modality for distinguishing meningiomas (somatostatin receptor expressing) from other tumours.