Retrosigmoid approach for glycerin rhizotomy in the treatment of trigeminal neuralgia without overt arterial compression: updated case series

Restricted access


Trigeminal neuralgia (TN) is a neuropathic pain disorder characterized by severe, lancinating facial pain that is commonly treated with neuropathic medication, percutaneous rhizotomy, and/or microvascular decompression (MVD). Patients who are not found to have distinct arterial compression during MVD present a management challenge. In 2013, the authors reported on a small case series of such patients in whom glycerin was injected intraoperatively into the cisternal segment of the trigeminal nerve. The objective of the authors’ present study was to report their updated experience with this technique to further validate this novel approach.


The authors performed a retrospective analysis of data obtained in patients in whom glycerin was directly injected into the inferior third of the cisternal portion of the trigeminal nerve. Seventy-four patients, including 14 patients from the authors’ prior study, were identified, and demographic information, intraoperative findings, postoperative course, and complications were recorded. Fisher’s exact test, unpaired t-tests, and Kaplan-Meier survival curves using Mantel log-rank test were used to compare the 74 patients with a cohort of 476 patients who received standard MVD by the same surgeon.


The 74 patients who underwent MVD and glycerin injection had an average follow-up of 19.1 ± 18.0 months, and the male/female ratio was 1:2.9. In 33 patients (44.6%), a previous intervention for TN had failed. On average, patients had an improvement in the Barrow Neurological Institute Pain Intensity score from 4.1 ± 0.4 before surgery to 2.1 ± 1.2 after surgery. Pain improvement after the surgery was documented in 95.9% of patients. Thirteen patients (17.6%) developed burning pain following surgery. Five patients developed complications (6.7%), including incisional infection, facial palsy, CSF leak, and hearing deficit, all of which were minor.


Intraoperative injection of glycerin into the trigeminal nerve is a generally safe and potentially effective treatment for TN when no distinct site of arterial compression is identified during surgery or when decompression of the nerve is deemed to be inadequate.

ABBREVIATIONS BNI = Barrow Neurological Institute; MS = multiple sclerosis; MVD = microvascular decompression; TN = trigeminal neuralgia.

Article Information

Correspondence Michael Lim: Johns Hopkins Hospital, Baltimore, MD.

INCLUDE WHEN CITING Published online March 8, 2019; DOI: 10.3171/2018.12.JNS182572.

Disclosures Dr. Bettegowda reports being a consultant for DePuy Synthes. Dr. Lim reports being a consultant for Aegenus, BMS, Regeneron, Oncorus, Boston Biomedical, Tocagen, SQZ Technologies, Stryker, and Baxter, and he has received research support from Arbor, Aegenus, Altor, BMS, Immunocellular, Celldex, Accuray, and DNAtrix.

© AANS, except where prohibited by US copyright law.



  • View in gallery

    Kaplan-Meier pain recurrence rate after treatment of patients who underwent MVD only and MVD+glycerin injection. No statistical significance was found (p = 0.08). Figure is available in color online only.





All Time Past Year Past 30 Days
Abstract Views 494 494 76
Full Text Views 59 59 6
PDF Downloads 45 45 1
EPUB Downloads 0 0 0


Google Scholar