T2 Hypointense Schwannoma Masquerading As A Vascular Lesion: A Case Report.

Spinal schwannomas are rare nerve root tumors that typically produce subtle symptoms from nerve root compression. These tumors are known to be heterogeneously hyperintense on T2-weighted MRI and avidly enhance with contrast. However, here we describe an L5 spinal schwannoma in a 66-year-old woman that was hypointense on T2-weighted imaging with other radiographic findings more closely aligning with a vascular lesion. The neuroradiologic characteristics on MRI, time resolved MR angiography, and catheter digital subtraction angiography are presented. The patient underwent a full workup for possible dural arteriovenous fistula and thrombosed venous varix before the nerve sheath tumor was discovered intraoperatively and confirmed as a schwannoma on histopathology.