Acta Scientific Neurology (ASNE) (ISSN: 2582-1121)

Research Article Volume 7 Issue 2

Efficacy of Internal Neurolysis for Atypical Facial Pain

Keisuke Onoda*, Kazunori Iwasa, Tomoyuki Naito, Takahiro Kumono, Tomihiro Wakamiya, Yuhei Michiwaki, Tatsuya Tanaka, Takashi Agari, Takashi Sugawara, Kazuaki Shimoji, Eiichi Suehiro, Fumitaka Yamane, Hiroshi Itokawa and Akira Matsuno

Department of Neurosurgery, International University of Health and Welfare, School of Medicine, Narita Hospital, Narita, Japan

*Corresponding Author: Keisuke Onoda, Department of Neurosurgery, International University of Health and Welfare, School of Medicine, Narita Hospital, Narita, Japan.

Received: December 27, 2023; Published: January 26, 2024


Background: Although microvascular decompression (MVD) for trigeminal neuralgia is an established fundamental treatment, approximately 4-5% of cases recur annually despite treatment. Compared with typical trigeminal neuralgia (TTN), atypical facial pain (AFP) with no triggers and persistent pain is reported to recur more often. The ideal treatment for AFP has not yet been established. Internal neurolysis (IN), in which the trigeminal nerve is physically divided longitudinally, has shown good results in cases of recurrence without vascular compression. In this study, we evaluated the usefulness of IN for treating AFP by analyzing patient outcomes in cases in which IN was administered.

Methods: Fifteen IN patients were enrolled. IN was added to conventional MVD in cases of venous compression, mild arterial compression, or severe adhesions, with the goal of preventing recurrence. Eight patients presented with AFP, and seven had TTN. Both groups were compared in terms of surgical outcomes using the Barrow Neurological Institute Pain Intensity Scale immediately after surgery and 1 year postoperatively. Surgery was performed using a conventional retrosigmoid approach. IN consists of the longitudinal transection of the trigeminal nerve in the cisternal portion, creating grooves that divide the nerve fibers.

Results: Both the TTN and AFP groups showed good outcomes for up to 1 year. No complications or recurrences were observed.

Conclusions: IN is a potential therapeutic option for AFP.

Keywords: Internal Neurolysis; Atypical Facial Pain; Microvascular Decompression; Trigeminal Neuralgia


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Citation: Keisuke Onoda., et al. “Efficacy of Internal Neurolysis for Atypical Facial Pain". Acta Scientific Neurology 7.2 (2024): 35-40.


Copyright: © 2024 Keisuke Onoda., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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