The outcomes of a second and third Gamma Knife radiosurgery for recurrent essential glossopharyngeal neuralgia

Abstract

Introduction: Gamma Knife radiosurgery (GKR) is a minimally invasive surgical option for drug-resistant essential glossopharyngeal neuralgia (GPN). The authors reviewed pain outcomes and complications in GPN patients who underwent a second or a third GKR for recurrent or persistent pain.

Methods: A retrospective review of all patients treated in a single center (Marseille, France) since 2004 was performed. Median prescribed dose was 85 Gy (range 70-90 Gy) at second GKR and 85 Gy at third GKR. Clinical outcome was evaluated using the Barrow Neurological Institute (BNI) scale.

Results: Six patients (4 males, 2 females) underwent second or third GKR. The median age was 70.2 years (range 64-83 years) at second GKR and 79.8 years at third GKR. No patient had any previous surgery but GKR. Five cases had a neurovascular conflict. Median follow-up period was 12 months (range 10-94 months) after second GKR and 16 months after third GKR. The median delay to initial pain freedom response was 30 days (range 3-120 days). One patient experienced pharyngeal hypoesthesia after second GKR. After a third GKR, up to 16 months, no side effects were encountered. At the last follow-up, 3 patients were BNI I, 2 were BNI IIIa, and one did not have any improvement.

Conclusions: Second GKR resulted in pain reduction with low risk of additional morbidity. In patients unsuitable for microvascular decompression, GKR as a repeat or third treatment for intractable GPN is safe and effective. Third GKR was not associated with any side effects up to 16 months after the procedure.

Keywords: Gamma Knife; Glossopharyngeal neuralgia; Radiosurgery; Stereotactic.