A Perforating Artery Compressing the Nerve Rootlet and Causing Glossopharyngeal Neuralgia

BACKGROUND: A surgical procedure for glossopharyngeal neuralgia (GPN) was selected from microvascular decompression, glossopharyngeal and upper vagal rhizotomy, or a combination of these procedures based on the presence of arteries compressing the glossopharyngeal and vagal rootlets. The offending artery is usually a main trunk or branch of the cerebellar arteries. A perforating artery is a known but uncommon variation of the offending artery that causes GPN. The appropriate procedure for such cases is unknown. OBJECTIVE: To analyze the clinical significance of the perforating artery in GPN, we describe 2 patients with a perforating artery compressing the rootlet, and its mobilization relieved neuralgia. We examined the validity of decompressing a perforating artery as an alternative to rhizotomy in such cases. METHODS: We independently reviewed 12 GPN patients treated with microvascular decompression. The patients' pain severity, medication doses, preoperative imaging studies, intraoperative findings, and outcomes were examined. RESULTS: Eleven patients had neurovascular compression of the glossopharyngeal nerve. In 2 of the patients, a perforating artery compressed the rootlet, thereby generating an indentation and creating a discoloration of the rootlet. Mobilizing the perforating artery with no additional rhizotomy provided complete pain relief with no significant complications and allowed the discontinuation of medications. CONCLUSION: Even a small perforating artery can cause GPN when it compresses the rootlet. In such cases, mobilization of the perforating artery with no additional rhizotomy is an effective surgical option.