Comparison of microvascular decompression and two isocenters gamma knife for the treatment of trigeminal neuralgia caused by vertebrobasilar compression

Abstract Objective: Vertebrobasilar dolichoectasia (VBD) is one of the uncommon causes of trigeminal neuralgia (TN). The main surgical treatments for TN caused by VBD (VBD-TN) are invasive microvascular decompression (MVD) and mini-invasive Gamma Knife radiosurgery (GKRS). However, the therapeutic effects of the two methods have not been clinically reported, so this study evaluated the outcomes of MVD and GKRS for patients with VBD-TN.Methods: The retrospective study of patients diagnosed with VBD-TN in Wuhan Union Hospital was performed from March 2011 to March 2019. A total of 80 patients were included in this study, and they were divided into the MVD group (n = 46) and GKRS group (n = 34) according to the surgical methods. Among patients in the GKRS group, all performed by two isocenters gamma knife. The imaging data, intraoperative findings, outcomes, and complications of the two groups were analyzed and compared.Results: Patients who underwent MVD were younger than patients who underwent GKRS (median ages were 61.1 and 65.4 years old, p=0.03). The average follow-up was 61.1 months for the MVD group and was 56.8 months for the GKRS group. The favorable outcomes (BNI score I-II) occurred in 97.8% of patients treated with MVD and in 78.9% of patients treated with GKRS (P=0.009). The favorable outcomes in the percentage of patients after MVD 1,3,5 and 7 years were 95.7%, 85.1%, 74.2%, and 74.2%. The corresponding percentages after GKRS were 76.5%, 66.2%, 56.6% and 47.2%, respectively (P=0.031). The postoperative complications (except facial numbness) in the MVD group were higher than those in the GKRS group (P=0.036), but the incidence of new and worsening facial numbness was higher in the GKRS group (P<0.001).Conclusions: For VBD-TN, MVD is superior to GKRS in obtaining and maintaining favorable outcomes, but it also comes with more complications other than facial sensation. Treatment choice can be tailored to a patient’s unique condition and wishes.