Unilateral hypoplasia of the trigeminal ganglion

Case report: We report a case of unilateral anaesthesia of the V ₁ (ophthalmic) division of the trigeminal cranial nerve presenting with persistent corneal erosions and ulceration secondary to trigeminal ganglion hypoplasia. The patient had a lifelong history of unexplained left-sided ophthalmic symptoms for which numerous diagnoses were provided. Cranial nerve testing demonstrated partial trigeminal dysfunction on the left side. Further investigation eliminated viral etiologies, and subsequent magnetic resonance imaging determined that the patient had a hypoplastic left trigeminal ganglion. Comments: We present the case to alert clinicians to the possibility of this rare condition.