Microvascular Decompression for Glossopharyngeal Neuralgia: Clinical Analyses of 30 Cases

Case report: Significance of the large rhomboid lip in microvascular decompression: insights from two clinical cases

The rhomboid lip (RL) is a layer of neural tissue that extends outside the fourth ventricle and is connected to the lateral recess of the fourth ventricle. Although this anatomical structure has been rigorously studied, it is often overlooked in microvascular decompression (MVD) surgery. In this report, we present two cases, one of hemifacial spasm (HFS) and one of glossopharyngeal neuralgia (GPN), in which a large RL was observed during surgery. We found that a large RL is easily confused with arachnoid cysts, and accurate identification and dissection are important to protect the lower cranial nerves.

Glossopharyngeal and vagoglossopharyngeal neuralgia: Long-term surgical outcomes in a single institution

BACKGROUND

Glossopharyngeal neuralgia (GPN) and vagoglossopharyngeal neuralgia (VGPN) are infrequent syndromes that can have great negative impact on a patient's quality of life. The objective of this study is to describe the characteristics and long-term results of patients with GPN-VGPN who are treated surgically with microvascular decompression (MVD) in one institution.

METHODS

This is a retrospective series of 20 patients with the diagnosis of GPN-VGPN who underwent MVD. Demographic characteristics, surgical results, complications, and long-term follow-up were analyzed.

RESULTS

The mean age of symptom onset was 51.25 years and the majority of patients were women (60%). The posterior inferior cerebellar artery was the main offending vessel (75%). The immediate MVD success rate was 100%, but during follow-up, two patients (10%) were diagnosed with VGPN and both cases presented pain recurrence. The mean follow-up was 120.4 (25-333) months. VGPN (P = 0.005) and a ≥5 day hospital stay (P = 0.032) were associated with unsuccessful outcomes. Two complications were documented, which resolved without sequelae. There was no surgical mortality.

CONCLUSION

MVD is an effective and safe treatment for long-term pain relief of GPN-VGPN. VGPN and a prolonged hospital stay were associated with poor outcomes. More studies are required to confirm these findings.

Factors Predicting Cerebrospinal Fluid Leaks in Microvascular Decompressions: A Case Series of 1011 Patients

BACKGROUND

Microvascular decompression (MVD) using a retrosigmoid approach is a highly effective, open-surgical procedure for neurovascular conflict in the posterior fossa, although there is a risk of postoperative cerebrospinal fluid (CSF) leak.

OBJECTIVE

To identify factors associated with postoperative CSF leakage after MVD.

METHODS

We retrospectively reviewed all patients who underwent MVDs at our institution from 2007 to 2020. Patient demographics, clinical diagnoses, and procedural characteristics were recorded and compared. Factors leading to CSF leak were analyzed using χ 2 , univariate, and multivariate regression.

RESULTS

Of 1011 patients who underwent MVDs, 37 (3.7%) presented with postoperative CSF leaks. In univariate analysis, the use of Cranios/Norian to obliterate the air cells was protective against CSF leak ( P = .01). Craniotomies ( P = .002), the use of dural substitutes such as Durepair ( P = .04), dural onlays such as DuraGen ( P = .04), muscle/fascia ( P = .03), and titanium mesh cranioplasty >5 cm ( P = .03) were associated with CSF leak. On multivariate analysis, only the presence of craniotomies ( P = .04) and nonprimary dural closure ( P = .03) were significant risk factors for CSF leak. When excluding the 34 (3.4%) patients who underwent a craniotomy, the lack of primary dural closure still remained significantly associated with postoperative CSF leak ( P = .04).

CONCLUSION

Our results represent one of the largest series of posterior fossa surgeries for a uniform indication in North America. Our study demonstrates increased risk for postoperative CSF leak when craniotomies are performed and when primary dural closure is not established. Given the small sample of patients who received a craniotomy, however, future studies corroborating this finding should be performed.

Current advances in the surgical treatment of glossopharyngeal neuralgia

Glossopharyngeal neuralgia (GPN) is a neurological condition characterized by paroxysmal, stabbing-like pain along the distribution of the glossopharyngeal nerve that lasts from a couple of seconds to minutes. Pharmacological treatment with anticonvulsants is the first line of treatment; however, about 25% of patients remain symptomatic and require surgical intervention, which is usually done via microvascular decompression (MVD) with or without rhizotomy. More recently, the use of stereotactic radiosurgery (SRS) has been utilized as an alternative treatment method to relieve patient symptoms by causing nerve ablation. We conducted a systematic review to analyze whether MVD without rhizotomy is an equally effective treatment for GPN as MVD with the use of concurrent rhizotomy. Moreover, we sought to explore if SRS, a minimally invasive alternative surgical option, achieves comparable outcomes. We included retrospective studies and case reports in our search. We consulted PubMed and Medline, including articles from the year 2000 onwards. A total of 36 articles were included for review. Of all included patients with glossopharyngeal neuralgia, the most common offending artery compressing the glossopharyngeal nerve was the posterior inferior cerebellar artery (PICA). MVD alone was successful achieving pain relief immediately postoperatively in about 85% of patients, and also long term in 65-90% of patients. The most common complication found on MVD surgery was found to be transient hoarseness and transient dysphagia. Rhizotomy alone shows an instant pain relief in 85-100% of the patients, but rate of long-term pain relief was lower compared to MVD. The most common adverse effects observed after a rhizotomy were dysphagia and dysesthesia along the distribution of the glossopharyngeal nerve. SRS had promising results in pain reduction when using 75 Gy radiation or higher; however, long-term rates of pain relief were lower. MVD, rhizotomy, and SRS are effective methods to treat GPN as they help achieve instant pain relief and the decrease use of medication. Patients with MVD alone presented with less adverse effects than the group that underwent MVD plus rhizotomy. Although SRS may be a viable alternative treatment for GPN, further studies must be done to evaluate long-term treatment efficacy.

Glossopharyngeal Neuralgia

Glossopharyngeal neuralgia (GPN) is a rare disease that must be differentiated from trigeminal neuralgia. The purpose of this article is to provide a comprehensive review of anatomy, pathophysiology, diagnostic criteria, and several options of treatment for GPN. Lessons learned through our experience of treating GPN are presented in detail, as well as cases of misdiagnosis and diagnostic pitfalls. Microvascular decompression (MVD) should be primarily considered for medically intractable GPN. Techniques employed in MVD for GPN are categorized and described. Especially, we underscore the advantages of the 'transposition' technique where insulating material is positioned 'off' the root entry zone (REZ), instead of 'on' it. We believe this 'off-the-REZ' technique can fundamentally prevent recurrence, if applicable. In addition, Gamma Knife radiosurgery can be an alternative option when a patient is ineligible for MVD, though it is categorized as a destructive procedure.

Long-term results of microvascular decompression with video endoscopy in the treatment of patients with atypical trigeminal neuralgia

The frequency of occurrence of atypical trigeminal neuralgia (aNTN) varies from 1 to 7 people per 100,000 population per year. The main cause of development is compression of the trigeminal nerve root (TN) by a vein and/or artery in the cerebellar cistern. To date, the final tactics of treatment of patients with aNTN have not been determined. The effectiveness of conservative methods of therapy does not exceed 50%. The aim of the study was to evaluate the results of microvascular decompression using video endoscopy in the treatment of patients with atypical trigeminal neuralgia. Methods. In the period from 2014 to 2021 34 patients with atypical HTN were operated on, of which 18 (53%) patients had neuropathic pain (more than 4 points on the DN4 scale), and 15 (44%) patients had a transformation of classical trigeminal neuralgia into atypical. Conservative therapy (carbamazepine, gabapentin, pregabalin), administered to all patients in the preoperative period, was not accompanied by a significant reduction in pain syndrome. The maximum intensity of pain upon admission to the hospital according to the visual analog scale (VAS) was 10 points, according to the severity of pain syndrome BNI (Barrow Neurological Institute) V (severe, persistent pain). All patients underwent internal affairs of the trigeminal nerve root with the use of Teflon; in 12 (35%) patients, in addition to a microscope, video endoscopy was additionally used. The average follow-up period after surgery was 3.4 1.7 years (from 1 to 5 years). Results. In all (100%) patients after surgery, the pain is completely stopped (BNI I). The total fiveyear excellent and good outcome of the disease on the J.Miller and BNI scale (I-II) was noted in 80% (n=27) of patients with atypical NTN. The risk of pain recurrence in the first three years after MVD was 14% (n=3), and after 5 years 34% (n=4). The use of video endoscopy made it possible to identify vessels compressing the root of the trigeminal nerve with minimal displacement of the cerebellum and cranial nerves when visualizing neurovascular conflict. Conclusion. The MVD method with video endoscopy is effective in the treatment of patients with aNTN

Routine postoperative admission to the neurocritical intensive care unit after microvascular decompression: necessary or can it be abandoned?

Postoperative neurocritical intensive care unit (NICU) admission of patients who underwent craniotomy for close observation is common practice. In this study, we performed a comparative analysis to determine if there is a real need for NICU admission after microvascular decompression (MVD) for cranial nerve disorders or whether it may be abandoned. The present study evaluates a consecutive series of 236 MVD surgeries performed for treatment of trigeminal neuralgia (213), hemifacial spasm (17), vagoglossopharyngeal neuralgia (2), paroxysmal vertigo (2), and pulsatile tinnitus (2). All patients were operated by the senior surgeon according to a standard protocol over a period of 12 years. Patients were admitted routinely to NICU during the first phase of the study (phase I), while in the second phase (phase II), only patients with specific indications would go to NICU. While 105 patients (44%) were admitted to NICU postoperatively (phase I), 131 patients (56%) returned to the ward after a short stay in a postanaesthesia care unit (PACU) (phase II). Specific indications for NICU admission in phase I were pneumothorax secondary to central venous catheter insertion (4 patients), AV block during surgery, low blood oxygen levels after extubation, and postoperative dysphagia and dysphonia (1 patient, respectively). There were no significant differences in the distribution of ASA scores or the presence of cardiac and pulmonary comorbidities like congestive heart failure, arterial hypertension, or chronic obstructive pulmonary disease between groups. There were no secondary referrals from PACU to NICU. Our study shows that routine admission of patients after eventless MVD to NICU does not provide additional value. NICU admission can be restricted to patients with specific indications. When MVD surgery is performed in experienced hands according to a standard anaesthesia protocol, clinical observation on a neurosurgical ward is sufficient to monitor the postoperative course. Such a policy results in substantial savings of costs and human resources.

Salvage gamma knife surgery for recurrent glossopharyngeal neuralgia following microvascular decompression: a retrospective case series

BACKGROUND

Although microvascular decompression (MVD) is recognized as the preferred therapy for drug-resistant idiopathic glossopharyngeal neuralgia (GPN), the management of recurrent GPN following MVD is seldom mentioned in the current literature. This study aims to demonstrate the efficacy and safety of salvage Gamma Knife surgery (GKS) in the treatment of recurrent GPN after MVD.

METHODS

From October 2012 to January 2018, seven patients (three males and four females) underwent salvage GKS for recurrent GPN following MVD, including two patients who received repeat GKS due to pain recurrence after their initial GKS salvage. The median age was 69 years (range 49-81 years) at first GKS and 72 years (67 years; 77 years) at second GKS. The delivered dose was 80 or 90 Gy at first GKS and 90 Gy at second GKS. Pain outcome was assessed according to the Barrow Neurological Institute (BNI) score.

RESULTS

The median duration of follow-up after first GKS was 68 months (range 29-89 months) and 45 months (56 months; 33 months) after second GKS. The median time to pain response was 24 days (range, 6-80 days). One patient experienced palatoglossal hyperesthesia after first GKS, and no complications were noted after second GKS. At the last follow-up, 4 patients were BNI I, 1 was BNI II, and 2 was BNI IIIa.

CONCLUSIONS

Salvage GKS is safe and effective for treating recurrent GPN after MVD, even for patients who experienced pain recurrence following their initial GKS salvage.

Reoperation after failed microvascular decompression for glossopharyngeal neuralgia

BACKGROUND

Microvascular decompression (MVD) is known as a safe and effective procedure to treat glossopharyngeal neuralgia (GN). However, some patients experienced poor pain relief after MVD, for which the mechanism is not clear yet. Reviewing the intraoperative findings and postoperative effect of reoperation for patients who failed the first MVD, is helpful to figure out why the first MVD for GN failed.

METHODS

There were eight patients with GN who failed first MVD. The possibilities for secondary GN were eliminated by physical and radiological examination. The reoperation through the previous incision was conducted, and appropriately, treatment was provided according to the intraoperative findings. The video data and prognosis of the reoperation were retrospectively reviewed. The reasons for the invalid first MVD were analyzed.

RESULTS

To the end of follow-up, there were 7 patients of pain-free, and one patient with occasional mild pain attacks (VAS 2). There was one patient who experienced transient hoarseness in 3 months after the reoperation. We summarized the causes for failed first MVD which were omission of the offending vessel in 3 cases, inadequate decompression of the nerve root in 2 cases, and excessive decompression materials which caused iatrogenic nerve root compression in 3 cases.

CONCLUSIONS

For patients with recurrent or failed after MVD, a thorough examination should be carried out to eliminate the possibility of secondary GN. Reoperation through the previous incision is safe and effective. The bone window should be close enough to the sigmoid sinus to aid the exposure of the nerve root. The nerve transection could be adopted if no offending vessels were found. And a multi-site decompression could be used when the vertebral artery is the offending vessel.

The Long-Term Outcome of CT-Guided Pulsed Radiofrequency in the Treatment of Idiopathic Glossopharyngeal Neuralgia: A Retrospective Multi-Center Case Series

Background

Safer and minimal invasive treatment options with minor side effects are in great demand in the treatment of glossopharyngeal neuralgia (GPN). Pulsed radiofrequency (PRF) is a micro-destructive procedure that could be applied repeatedly without irreversible damage to target tissue. However, few studies have reported the long-term clinical outcomes of PRF in the management of idiopathic GPN patients.

Methods

We retrospectively investigated the efficacy and safety of computed tomography (CT)-guided PRF in the treatment of 30 patients with idiopathic GPN in a multi-center clinical study. Numeric rating scale (NRS) score was used to evaluate pain intensity before and after PRF treatment. The effective rate was defined as the percentage of patients with NRS reduction of more than 50%. Baseline characteristics, surgical records, initial pain relief, time to take effect, long-term outcomes, patient satisfaction using a five-level Likert Scale, the incidence of recurrence as well as subsequent treatment choices, intraoperative and postoperative complications were retrieved from electronic medical records.

Results

A total of 30 idiopathic GPN patients who received PRF under CT-guidance were included in our study and the initial effective rate was 93.3%. The cumulative proportion of patients with satisfactory pain relief survival was 93.3% at 12 months, 89.6% at 24 months, 85.3% at 36 months, 79.6% at 48 months, 73.0% at 60 months and 72 months, and 54.8% at 84 months, 108 months as well as 120 months. No serious morbidity or mortality were observed in any of the cases. The median patient satisfaction in Likert scale rating was 4.0 (IQR, 3.0–5.0).

Conclusion

According to our results, PRF is an effective and safe therapy for patients with idiopathic GPN. This minimally invasive, micro-destructive, neuro-modulatory technique could be a potential intervention of choice for the treatment of GPN patients who respond poorly to pharmacological treatment.

Microvascular decompression: is routine postoperative CT imaging necessary?

BACKGROUND

Postoperative head CT imaging is routinely performed for detection of postoperative complications following intracranial procedures. However, it remains unclear whether with regard to radiation exposure, costs, and possibly lack of consequences this practice is truly justified in various operative procedures. The objective of this study was to analyze whether routine postoperative CT imaging after microvascular decompression (MVD) is necessary or whether it may be abandoned.

METHODS

A series of 202 MVD surgeries for trigeminal neuralgia (179), hemifacial spasm (17), vagoglossopharyngeal neuralgia (2), paroxysmal vertigo (2), and pulsatile tinnitus (2) operated by the senior surgeon (JKK) and who had postoperative routine CT imaging was analyzed.

RESULTS

Routine postoperative CT imaging detected small circumscribed postoperative hemorrhage in 9/202 (4.4%) instances. Hemorrhage was localized at the site of the Teflon felt (1/9), the cerebellum (4/9), in the frontal subdural space (3/9), and in the frontal subarachnoid space (1/9). In two patients, asymptomatic hemorrhage was accompanied by mild cerebellar edema (1%), and another patient had mild transient hydrocephalus (0.5%). Furthermore, there were small accumulations of intracranial air in 86/202 instances. No other complications such as infarction or skull fracture secondary to fixation with the Mayfield clamp were detected. MVD had been performed for trigeminal neuralgia in 6/9 patients, for hemifacial spasm in 2/9, and in one patient with both. No patient underwent a second surgery. Hemorrhage was symptomatic at the time of imaging in only one instance who had mild postoperative gait ataxia. Two patients with hemorrhage developed delayed facial palsy most likely unrelated to hemorrhage which remitted with corticosteroid treatment. At 3-month follow-up and at long-term follow-up, they had no neurological deficits.

CONCLUSION

Routine postoperative CT imaging is not necessary after MVD in a standard setting in patients who do not have postoperative neurological deficits.

Microvascular Decompression Alone without Rhizotomy Is an Effective Way of Treating Glossopharyngeal Neuralgia: Clinical Analysis of 46 Cases

BACKGROUND

Microvascular decompression (MVD) has been the right choice for glossopharyngeal neuralgia (GPN) patients. However, whether glossopharyngeal/vagal nerve root rhizotomy should be combined with MVD is still controversial.

OBJECTIVE

To evaluate whether glossopharyngeal/vagal nerve root rhizotomy during MVD is necessary for the treatment of GPN.

METHODS

We performed a retrospective study of 46 GPN patients who underwent MVD surgery alone in our hospital, and their patient demographics, clinical presentations, and intraoperative findings are shown. The immediate and long-term follow-up outcomes were investigated to show the treatment's efficiency and safety; the outcome was also compared with our previous study. The relevant literature was reviewed to show complications for GPN patients undergoing glossopharyngeal/vagal nerve root rhizotomy with MVD.

RESULTS

The most common offending vessel was the posterior inferior cerebellar artery (60.9%). 100% of the patients were pain-free (score of I on the Barrow Neurological Institute pain intensity [BNI-P] scale) immediately after MVD surgery, while 1 patient relapsed with occasional pain 12 months after the operation (score of III on the BNI-P scale). Poor wound healing and hearing loss were found in 1 case each. No complications related to the glossopharyngeal nerve/vagal nerve were reported. Some surgical techniques, such as thorough exploration of the CN IX-X rootlets, full freeing from arachnoid adhesions, and usage of a moist gelatin sponge, can improve the success rate of the operation.

CONCLUSIONS

MVD alone without rhizotomy is an effective and safe method for patients with GPN.

CT-guided percutaneous radiofrequency thermocoagulation for glossopharyngeal neuralgia: A retrospective clinical study of 117 cases

OBJECTIVE

Glossopharyngeal neuralgia (GPN) is a rare disorder of the ninth cranial nerve. Percutaneous radiofrequency thermocoagulation (PRT) is an established treatment for neuropathic pain. Since PRT was first applied with GPN, only a few studies have provided detailed reports on its clinical outcomes and complications, and the number of cases was small. The aim of this study was to investigate the effects, incidence rates, and severity of adverse events of computed tomography (CT)-guided PRT in 117 patients with GPN.

PATIENTS AND METHODS

A total of 117 patients with idiopathic GPN underwent CT-guided PRT from July 2004 to December 2016. A retrospective review of medical records was performed to investigate baseline characteristics and immediate outcomes after operation. Long-term outcomes were obtained via telephone interviews. Patients were followed up at 3 months, 6 months, and thereafter, every year after operation. According to Barrow Neurological Institute (BNI) pain scale, the effects of this treatment were categorized into 5 levels. Adverse events, frequencies, severity, and recovery times of complications were recorded.

RESULTS

Patients who were classified into BNI class I and BNI class II experienced excellent pain relief. Ninety-six patients (82.1%) achieved "excellent" pain relief immediately after treatment. The mean follow-up period was 73.6 months (range, 13-150). With regard to long-term outcomes, the percentage of patients who experienced "excellent" pain relief was 75.9% at 1 year, 63.0% at 3 years, 54.0% at 5 years, 44.2% at 10 years, and 39.3% at 12.5 years. Complications, which included dysphagia, lingual numbness, pharynx and larynx numbness, hoarseness, and abnormal sense of taste, were graded 1 as defined by the Landriel Ibanez classification, and all complications disappeared within 12.9 ± 5.1 weeks.

CONCLUSION

This study indicates that PRT is a minimally invasive procedure that leads to minor complications and is proven to have immediate and long-term effectiveness for managing GPN. It is especially suitable for patients with contraindication to surgery and patients who require recurrent treatment. We provide a detailed report of the adverse events experienced by GPN patients who underwent PRT.

Does Glossopharyngeal Neuralgia Need Rhizotomy in Neurovascular Decompression Surgery?

OBJECTIVE

To evaluate and compare the long-term efficacy and safety of microvascular decompression (MVD) and glossopharyngeal nerve roots rhizotomy (GNR) in the treatment of glossopharyngeal neuralgia (GN).

PATIENTS AND METHODS

The data of 37 patients with glossopharyngeal neuralgia undergoing MVD alone and MVD + GNR from July 2004 to March 2017 were analyzed retrospectively. Among them, 22 were MVD alone and 15 were MVD + GNR. All patients underwent preoperative cocaine experiments to verify diagnoses, preoperative magnetic resonance imaging examinations to detect compressing vessels near the root entry zone of the glossopharyngeal nerve. Operation via retrosigmoid approach, keyhole craniotomy, and postoperative efficacy was followed up.

RESULTS

Efficacy: In the 22 patients with MVD alone, 19 patients were cured and 3 patients improved. In the 15 patients with MVD + GNR, 14 patients were cured and 1 patient improved. There was no significant difference between the 2 groups (χ test, P > 0.05).

COMPLICATIONS

Postoperative complications in MVD group: 2 patients had short-term hoarseness and drinking cough, 1 patient with cerebrospinal fluid leakage, 1 patient with intracranial infection, 1 patient with ipsilateral hearing loss, and no deaths; postoperative complications in MVD + GNR group: permanent hoarseness in 2 patients, short-term drinking cough and hoarseness in 4 patients, ipsilateral facial paralysis in 1 patient, 1 patient with cerebrospinal fluid leakage, no intracranial infection and death. The incidence of postoperative hoarseness and drinking cough in MVD + GNR group was higher than that in MVD group (χ test, P < 0.05).

CONCLUSION

The MVD alone was a safe and effective method for the treatment of primary glossopharyngeal neuralgia, the efficacy was equivalent to MVD + GNR, and had low incidence of hoarseness and drinking cough.

Glossopharyngeal Neuralgia Treatment Outcomes After Nerve Section, Microvascular Decompression, or Stereotactic Radiosurgery: A Systematic Review and Meta-Analysis

BACKGROUND

Glossopharyngeal neuralgia (GPN) is a rare neuralgic pain syndrome amenable to neurosurgical treatments, including nerve section (NS), microvascular decompression (MVD), and stereotactic radiosurgery (SRS). However, thorough comparisons of the modalities have not been performed to date. The objective of the present study was to compare the pain and complication outcomes after these approaches to GPN.

METHODS

Searches of 7 electronic databases from inception to June 2018 were conducted following the appropriate guidelines. The incidence rates (IRs) of short-term (≤3 months) and long-term (≥12 months) pain relief and complications were extracted and analyzed using a meta-analysis. Meta-regression was used to assess for heterogeneity.

RESULTS

A total of 792 GPN cases managed by NS, MVD, or SRS were described by 6, 11, and 6 studies, reporting outcomes for 282 (36%), 446 (56%), and 67 (8%) cases. The short-term pain relief rate was highest after NS postoperatively (IR, 94%; 95% confidence interval [CI], 88%-98%) and lowest after SRS at 3 months postoperatively (IR, 80%; 95% CI, 68%-96%). The postoperative complication rate was greatest after MVD (IR, 26%; 95% CI, 16%-38%) and lowest after SRS (IR, 0%; 95% CI, 0%-4%). The long-term pain relief rate was greatest after NS (IR, 96%; 95% CI, 91%-99%) and lowest after SRS (IR, 82%; 95% CI, 67%-94%). Statistically significant differences between the approaches were found for each outcome.

CONCLUSION

Neurosurgical treatment of GPN is frequently performed by 1 of 3 modalities with unique outcomes profiles. NS might provide the most favorable treatment response, with respect to short- and long-term pain relief and postoperative outcomes.

Veins of the Cerebellopontine Angle and Specific Complications of Sacrifice, with Special Emphasis on Microvascular Decompression Surgery. A Review

Good knowledge of the anatomy of veins is of crucial importance for the functional surgery of cranial nerve (CN) disorders, especially microvascular decompression for trigeminal neuralgia (TN), hemifacial spasm (HFS), and vagoglossopharyngeal neuralgia (VGPN). Although controversial, veins may be involved in neurovascular conflicts and may constitute dangerous obstacles to access to the CNs. With the aim of estimating the implications of veins in those diseases and evaluating the linked surgical difficulties, we carried out a review of the literature from 2000 to the end of February 2018. For this review, articles found on PubMed that gave enough precision about veins were retained (39 articles on TN, 38 on HFS, 8 on VGPN, and 26 on complications related to venous sacrifices). Before this review, we described a simplified anatomic classification of veins, amenable to easing the surgical approach to CNs. Access to the trigeminal nerve, via the infratentorial-supracerebellar route, is almost always affected by the superficial superior petrosal venous system, whereas access to the facial and cochleovestibular complex as well as to the lower CNs, through the infrafloccular trajectory, is almost always exempt of important venous obstacles. Respective incidences of venous compression at the origin of hyperactive CN syndromes are given. The percentages of a venous conflict alone were calculated at 10.8% for TN, 0.1% for HFS, and 2.9% for VGPN. We review the complications considered in relation with venous sacrifices. Precautions to minimize these complications are given.

Management of Recurrent Glossopharyngeal Neuralgia Following Microvascular Decompression Surgery

BACKGROUND

Glossopharyngeal neuralgia (GPN) is a rare condition, commonly misdiagnosed as trigeminal neuralgia. Microvascular decompression (MVD) is considered the first line of treatment in medically refractive idiopathic GPN, and the recurrence rate is reported to be 7.1%. We present our first case report on the surgical management of a patient with recurrent GPN and analyze the possible causes for recurrence after MVD.

CASE DESCRIPTION

A 73-year-old gentleman was referred to us with a diagnosis of recurrent left GPN. He was diagnosed 6 years ago with left mandibular branch trigeminal neuralgia for the complaint of left-side tongue pain. He received left mandibular nerve block twice earlier and Gamma Knife radiotherapy 2 years ago without relief. A year ago he was diagnosed with GPN by a neurosurgeon, and MVD was performed. The posterior inferior cerebellar artery and vertebral artery were the offending vessels and were interposed with Teflon. After a temporary pain relief, the patient had a recurrence. Redo-MVD with transposition of the vertebral artery and further interposition of posterior inferior cerebellar artery did not help. After referral to us, we operated on the patient again and found 2 small arteries at the root entry zone (REZ). Interposition with Teflon and splitting of the rootlets relieved the pain.

CONCLUSIONS

MVD is considered the first line of treatment in drug-resistant idiopathic GPN. Thorough exploration of REZ for small arteries and veins is mandatory to prevent recurrence. Vascular compression can occur at the cisternal portion or at the REZ. In recurrent cases, splitting of the glossopharyngeal nerve rootlets adds to the good outcome.