Gamma Knife Radiosurgery for Recurrent Glossopharyngeal Neuralgia after Microvascular Decompression

Abstract

Background: We report the first application of Gamma Knife radiosurgery (GKR) for recurrent glossopharyngeal neuralgia (GN) after microvascular decompression (MVD). The patient is a 51-year-old male with left-sided GN. He underwent MVD and did well for almost 4 years. Later on, the patient started to experience recurrent intolerable throat pain, frequently 10/10 in intensity. Based on the application of radiosurgery for trigeminal neuralgia, GKR was offered to the patient. Methods: After careful identification of the nerve with the assistance of a neuroradiologist, we targeted the nerve root complex, which is the cisternal portion of the nerve, using the Coherent Oscillatory State Acquisition for the Manipulation of Image Contrast (COSMIC) pulse sequence with contiguous 1-mm slices obtained by an 1.5 Tesla MRI. The radiosurgery was planned utilizing the Leksell Gamma Plan version 8.1. A single shot with a 4-mm collimator was used to deliver 80 Gy to the 100% isodose line. Results: Four weeks after the treatment, the patient began to notice significant pain relief. At the 12-month follow-up, the patient’s pain, which was intolerable prior to radiosurgery, was mild and occasional. Conclusion: GKR, which is now widely used for refractory trigeminal neuralgia, can be considered for refractory or recurrent GN. With a multidisciplinary approach and advanced neuroimaging, GKR is feasible for GN after MVD, despite the shortness of the intracranial cisternal nerve portion. Further studies are necessary to establish the role of GKR for refractory GN after MVD; however, given its rarity and the lack of experience with GKR for this condition, retrospective studies with dozens of patients are almost impossible at this time.

Current neurosurgical management of glossopharyngeal neuralgia and technical nuances for microvascular decompression surgery

“…27,28,38 Most recently, stereotactic radiosurgery has also been explored. 48,59,70 Although cranial nerve IX rhizotomy is low risk 66 and has been advocated during MVD for GPN, 69 the efficacy of cranial nerve X rhizotomy, when considering the asso ciated risks, remains less defined. We therefore attempted a comprehensive review of the literature to explore the role of cranial nerve X rhizotomy in a large group of pa tients.…”

Practical considerations of linear accelerator‐based frameless extracranial radiosurgery for treatment of occipital neuralgia for nonsurgical candidates

“…SRS for functional diseases including neuralgias has been well established with demonstrable precision using both frame and frameless approaches . Kim et al.…”

“…Although occipital neuralgia has been reported to be a complication resulting from frame installation for frame‐based radiosurgery, the use of SRS for the treatment of occipital neuralgia has not been reported to date . The success of radiosurgery in the management of trigeminal and glossopharyngeal neuralgia (both cranial‐based functional diseases) has been well established . SRS for trigeminal neuralgia and glossopharyngeal neuralgia involves single‐fraction high doses to the isocenter placed along the course of the nerve after exiting the central nervous system.…”

Gamma Knife Radiosurgery for Glossopharyngeal Neuralgia by Targeting the Medial Cisternal Segment of the Glossopharyngeal Nerve: Report of 3 Cases

“…The va- gal meatus is inevitably included in the 50% isodose area [12,[14][15][16][17][18] . The vagus nerve may receive a much higher degree of radiation than in targeting the cisternal segment of the glossopharyngeal nerve.…”