====== Retrosigmoid approach for glycerin rhizotomy ======

{{ ::retrosigmoid_approach_for_glycerin_rhizotomy.png?200|}}

In [[2013]] Goodwin et al., performed a [[retrospective]] analysis of patients who received standard [[microvascular decompression]] and injection of [[glycerin]] to the inferior third of the [[Trigeminal nerve cisternal portion]] anterior to the [[root entry zone]] with lack of a compressive vessel on MRI as the primary indication. Fourteen patients were identified and demographic information, post-operative course and [[complication]]s were recorded.

There were eleven [[female]]s and three [[male]]s with an average age at time of surgery of 54.8 years. 100% of patients reported that their trigeminal pain was significantly improved following surgical [[intervention]]. Four out of fourteen patients reported a 50-80% decrease from the pre-surgery baseline pain at one month and three month follow up. One patient developed a [[CSF]] [[leak]], and no surgical site [[infection]]s or [[motor deficit]]s were observed.

Intra-operative glycerin rhizotomy in conjunction with [[microvascular decompression]] can be used to safely treat patients suffering from [[trigeminal neuralgia]]
((Goodwin CR, Yang JX, Bettegowda C, Hwang B, James C, Biser A, Raza S, Bender
M, Carson B, Lee JY, Lim M. Glycerol rhizotomy via a retrosigmoid approach as an 
alternative treatment for trigeminal neuralgia. Clin Neurol Neurosurg. 2013
Dec;115(12):2454-6. doi: 10.1016/j.clineuro.2013.09.009. Epub 2013 Sep 25. PubMed
PMID: 24161889.
)).

In 2019 their updated experience with this technique to further validate this novel approach by a [[retrospective]] [[analysis]] of [[data]] obtained in [[patient]]s 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 [[logrank 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 leakage]], 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
((Kim TY, Jackson CM, Xia Y, Mashouf LA, Patel KK, Kim ES, Hung AL, Wu A,
Garzon-Muvdi T, Bender MT, Bettegowda C, Lee JYK, Lim M. Retrosigmoid approach
for glycerin rhizotomy in the treatment of trigeminal neuralgia without overt
arterial compression: updated case series. J Neurosurg. 2019 Mar 8:1-7. doi:
10.3171/2018.12.JNS182572. [Epub ahead of print] PubMed PMID: 30849763.
)).

===== References =====