Fully endoscopic microvascular decompression for the treatment of hemifacial spasm, trigeminal neuralgia, and glossopharyngeal neuralgia: a retrospective study
Authors: Peng Weicheng , Zhao Rui , Guan Feng , Liang Xin , Jing Bei , Zhu Guangtong , Mao Beibei , Hu Zhiqiang 
Published: October 2023

Abstract
Background
Microvascular decompression (MVD) is already the preferred surgical treatment for medically refractory neurovascular compression syndromes (NVC) such as hemifacial spasm (HFS), trigeminal neuralgia (TN), and glossopharyngeal neuralgia (GPN). Endoscopy has significantly advanced surgery and provides enhanced visualization of MVD. The aim of this study is to analyze the efficacy and safety of fully endoscopic microvascular decompression (E-MVD) for the treatment of HFS, TN, and GPN, as well as to present our initial experience.

Materials and methods
This retrospective case series investigated fully E-MVD performed in 248 patients (123 patients with HFS, 115 patients with TN, and 10 patients with GPN ) from December 2008 to October 2021 at a single institution. The operation duration, clinical outcomes, responsible vessels, intra- and postoperative complications, and recurrences were recorded. Preoperative and immediate postoperative magnetic resonance imaging (MRI) and computerized tomography (CT) were performed for imageological evaluation. The Shorr grading and Barrow Neurological Institute (BNI) pain score were used to evaluate clinical outcomes. The efficacy, safety, and risk factors related to the recurrence of the operation were retrospectively analysed, and the surgical techniques of fully E-MVD were summarised.

Results
A total of 248 patients (103 males) met the inclusion criteria and underwent fully E-MVD were retrospectively studied. The effective rate of 123 patients with HFS was 99.1%, of which 113 cases were completely relieved and 9 cases were significantly relieved. The effective rate of 115 patients with TN was 98.9%, of which 105 cases had completely pain relieved after surgery, 5 cases had significant pain relieved, 4 cases had partial pain relieved but still needed to be controlled by medication. The effective rate of 10 patients with GPN was 100%, 10 cases of GPN were completely relieved after surgery. As for complications, temporary facial numbness occurred in 4 cases, temporary hearing loss in 5 cases, dizziness with frequent nausea and vomiting in 8 cases, headache in 12 cases, and no cerebral hemorrhage, intracranial infection, and other complications occurred. Follow-up ranged from 3 to 42 months, with a mean of 18.6 ± 3.3 months. There were 4 cases of recurrence of HFS and 11 cases of recurrence of TN. The other effective patients had no recurrence or worsening of postoperative symptoms. The cerebellopontine angle (CPA) area ratio (healthy/affected side), the length of disease duration, and the type of responsible vessels are the risk factors related to the recurrence of HFS, TN, and GPN treated by fully E-MVD.

Conclusions
In this retrospective study, our results suggest that the fully E-MVD for the treatment of NVC such as HFS, TN, and GPN, is a safe and effective surgical method. Fully E-MVD for the treatment of NVC has advantages and techniques not available with microscopic MVD, which may reduce the incidence of surgical complications while improving the curative effect and reducing the recurrence rate.