Abstract

Trigeminal neuralgia is lancinating pain of a few seconds duration triggered by minor sensory stimuli such as speaking, chewing or even a breeze on the face. Vascular compression of the trigeminal nerve at the root entry zone and other vessels has been implicated in its cause. Despite the initial success of medical treatment in some cases, however, many patients become refractory over time and eventually require surgical intervention. This report describes a case involving a 62-year-old woman who presented with right orbital pain provoked by, among others, exercise and cold. Medication proved to be ineffective and, after magnetic resonance imaging, microvascular decompression and surgical observation, the diagnosis became clearer. The case highlights the importance of preoperative imaging and careful intraoperative findings to determine whether variant arteries are responsible for trigeminal neuralgia.A patient who presented with trigeminal neuralgia associated with a persistent primitive trigeminal artery (PPTA) is presented. A 62-year-old woman suffering from right orbital pain was admitted to the hospital. Medical treatment for three months was ineffective, and her neuralgia had deteriorated and gradually spread in the maxillary division. Magnetic resonance imaging demonstrated the flow void signal attached to the right trigeminal nerve. Thus, microvascular decompression was performed. The superior cerebellar artery was the responsible artery, and it was transposed to decompress the trigeminal nerve. After this manoeuvre, an artery was identified running parallel to the trigeminal nerve toward Meckel’s cave. The artery, which turned out to be a PPTA, communicated with the basilar artery. The PPTA was carefully observed, and it was found not to be the artery causing the neuralgia because it did not compress the nerve at surgical observation. No additional procedure between the PPTA and the trigeminal nerve was performed. The patient’s symptom improved dramatically following surgery, and her postoperative course was uneventful. Postoperative three-dimensional computed tomography showed the PPTA. The findings in the present case suggest that transposition of the responsible artery effectively decompresses the root entry zone and assists in determining whether the PPTA is affecting the trigeminal nerve.