Optic Nerve Root Enhancement in Gadolinium-Enhanced Magnetic Resonance Imaging of Rathke's Cleft Cyst.

Background: Although most patients with Rathke's cleft cysts (RCCs) remain asymptomatic throughout their lives, visual impairment in RCCs usually indicates surgical interventions, including endoscopic drainage of the cyst. We report a case of RCC with unique findings in the optic nerve root (ONR) by magnetic resonance imaging (MRI).

Case Description: A 58-year-old man admitted to our hospital complained of progressive left visual impairment. Preoperative computed tomography MRI revealed a suprasellar cystic lesion that extended anteriorly, and the bilateral ONRs were lateralized with the cyst and were partially enhanced with gadolinium administration. The cyst content was drained, and the cyst wall was partially removed by endoscopic transsphenoidal surgery. Postoperatively, the patient was administered corticosteroid intravenously for 3 days, and his visual acuity improved dramatically. Postoperative MRI revealed that the volume of the cyst decreased, and the position of the bilateral ONRs normalized. Additionally, enhancement of the ONRs with gadolinium administration was not observed. Histological examination of the surgical specimen revealed a ciliated single-layer columnar epithelium with inflammatory cell infiltration.

Conclusions: To our knowledge, we report the first case of a patient with RCC with ONR enhancement with gadolinium administration on MRI. This unique finding might prove that inflammation is one of the causes of visual impairment in RCC as in optic neuritis.