Importance of testing visual field in one-eyed patient to diagnose a rare case of congenital neuroanomaly

Persistent craniopharyngeal canal (PCC) is a rare congenital anomaly that appears as a linear canal running from the sella turcica through the clivus and into the nasopharynx. Correct diagnosis of a PCC plays a significant role in further management of this lesion. We report a rare case of PCC presented with a complaint of diminution of vision. Temporal visual field loss was detected on the confrontation test and confirmed on perimetry. PCC was diagnosed on neuroimaging. Doing a visual field test as a part of a routine ophthalmic examination may lead you to early diagnosis and intervention of rare entities, which can be life-saving for the patient.