ABSTRACT
We present a rare case of an intradural ventral arteriovenous fistula (AVF) mimicking an intramedullary ependymoma. A 46-year-old woman presented with sudden onset of right leg weakness, which she had been experiencing for two weeks. Whole-spine magnetic resonance imaging (MRI) scan revealed a 0.5-cm-sized intramedullary lesion of high signal with a dark signal rim on a T2-weighted image at the T9 level. The T1-weighted MRI after contrast enhancement revealed a nodular and rim-like enhancement. However, a signal void, likely to be seen in the case of an engorged vein, was not obvious, thus giving the impression of an intramedullary ependymoma. Surgery was planned, but was aborted due to the observation of a large engorged vein as soon as the dura was opened.