2022 Volume 31 Issue 8 Pages 524-529
Trigeminal neuralgia (TN) caused by the primitive trigeminal artery (PTA) and PTA variants is very unusual, accounting for 0.2-0.6% of TN cases, particularly the intermediate PTA type which is extremely rare and has only been reported twice in previous studies. We describe a case of TN caused by an anomalous artery originating directly from the PTA.
A 68-year-old woman with a 4-year history of TN in the right V2 distribution visited our hospital. The patient's pain was poorly controlled with oral medicine. The 3D MRI/MRA fusion and MR constructive interference in steady state (CISS) images revealed an abnormal artery branching from the PTA compressing the trigeminal nerve in the cerebellopontine angle. During microvascular decompression (MVD), the offending artery was transposed at two points on the trigeminal nerve, the root entry zone, and the cisternal portion. The patient's TN improved immediately after surgery. The patient's postoperative course was uneventful.
Both, 3T MRI/MRA 3D fusion and CISS images were useful in identifying the anatomical relationship between the PTA and the trigeminal nerve, thus, allowing the optimal operative strategy.
