Microvascular decompression for trigeminal neuralgia attributable to the vertebrobasilar artery: decompression technique and significance of separation from the nerve root

Arterial Hypertension After Macrovascular Decompression of Vertebrobasilar Dolichoectasia: Rethinking the Cause-Effect Relationship

OBJECTIVE

This study evaluates the short-term and long-term efficacy, safety, and blood pressure (BP) outcomes in patients with hyperactive dysfunction syndromes (HDSs) caused by neurovascular conflict (NVC) from vertebrobasilar dolichoectasia (VBDE) treated with macrovascular decompression (MaVD), with a focus on BP changes postsurgery.

METHODS

We retrospectively analyzed 38 patients with HDS due to VBDE who underwent MaVD at Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Istituto Neurologico Carlo Besta, Milan. Patients were grouped based on BP changes: worsened hypertension (HT), de novo HT, stable HT, and no HT. Demographic, clinical, surgical, and BP data were recorded and analyzed.

RESULTS

The majority of patients (65.8%) had hemifacial spasm, and 50% were hypertensive preoperatively. Postoperatively, 65.8% developed HT, with 52% showing worsened preoperative HT and 24% developing new HT. MaVD resolved symptoms in 86.8% of patients, with partial resolution in 13.1%. Left-sided NVC was more common, and preoperative HT was significantly associated with postoperative BP elevation. Complications included facial nerve deficits (13.1%) and hearing impairment (21%).

CONCLUSIONS

MaVD proves highly effective in treating HDS from VBDE, with most patients achieving complete symptom resolution. However, a significant proportion experienced increased BP postoperatively, especially those with preexisting HT. These findings support Jannetta et al.'s theory of neurogenic HT and suggest that cardiovascular risk factors like age, male sex, and obesity may predispose patients to BP increases. Left-sided NVC and glossopharyngeal neuralgia may be protective. The transient nature of BP elevation indicates possible long-term compensation. Further studies are needed to clarify the mechanisms behind BP changes and improve management strategies postsurgery.

Interposition versus transposition technique in microvascular decompression for trigeminal neuralgia secondary to vertebrobasilar dolichoectasia: a systematic review and pooled meta-analysis

Introduction

Limited data are available comparing the interposition and transposition techniques for microvascular decompression (MVD) in patients with trigeminal neuralgia (TN) secondary to vertebrobasilar dolichoectasia (VBD); this study aims to review current findings on TN associated with VBD and compare the interposition and transposition techniques in terms of surgical morbidity and patient outcomes.

Methods

Following the PRISMA guidelines, PubMed/Medline, Web of Science, and SCOPUS databases were searched to identify studies reporting patients undergoing MVD for TN secondary to VBD. The studies were divided into two groups, interposition and transposition, based on the microvascular decompression technique used. Studies not reporting the diagnostic criteria, included less than five cases, or were not available in English were excluded.

Results

Fourteen eligible papers were retrieved, of which five studies reported cases undergoing the interposition technique, eight studies for the transposition technique, and one study reported cases from both groups. Data including preoperative and postoperative BNI class, comorbidities, and postoperative complications were retrieved to analyze and compare the two techniques in terms of efficacy and long-term outcomes in treating TN secondary to VBD.

Conclusion

Both interposition and transposition techniques for MVD yield high rates of pain relief in patients with TN secondary to VBD. While both approaches demonstrate similar efficacy, the interposition method is associated with a lower rate of long-term complications. Further research, preferably through randomized prospective studies, is needed to refine surgical strategies and improve patient outcomes.

Microvascular Decompression for Trigeminal Neuralgia Secondary to Vertebrobasilar Dolichoectasia: Review of the Literature and Illustrative Case

Classical trigeminal neuralgia (TN) is a chronic pain disorder characterized by severe, unilateral facial pain, often resulting from vasculonervous conflict. A less common cause of TN is vertebrobasilar dolichoectasia (VBD). Microvascular decompression (MVD) is the preferred surgical intervention for TN, but in case of VBD, the surgical procedure is more complex due to the aberrant vascular anatomy. This study aims to review the evidence on MVD for VBD-induced TN, and analyze operative challenges, efficacy, and postoperative outcomes. An illustrative case is also presented. We report on the case of a 62-year-old male with a 7-year history of right-sided TN affecting the maxillary (V2) and mandibular (V3) territories. The patient underwent MVD using the interposition technique, where Teflon sponges were placed between the basilar artery and the nerve. Postoperatively, the patient experienced complete pain relief without neurological deficits. At 12 months follow-up, the patient remained pain-free and off medications. We performed an extensive literature review using PubMed, Scopus, and Web of Sciences, highlighting the most relevant studies and findings on the topic. The literature review showed that, while MVD is effective in providing long-term pain relief in VBD-induced TN, the choice between interposition and transposition techniques remains debated. Interposition is easier to perform but may inadvertently increase nerve compression in some cases, whereas transposition offers more definitive decompression but carries higher technical risks. Our case and the available literature highlight the importance of individualized treatment planning in achieving optimal outcomes for patients with VBD-induced TN. Further research is needed to refine surgical techniques and minimize complications in this subset of TN patients.

Parent artery occlusion for flow-related aneurysms at the proximal segment of the main feeding arteries of cerebellar arteriovenous malformations

BACKGROUND

Flow-related aneurysms (FRAs) associated with cerebellar arteriovenous malformations (AVMs) are complicated, and their management is difficult. We performed a retrospective study to explore the efficacy and outcome of parent artery occlusion (PAO) for FRAs at the proximal segment of the main feeding arteries of cerebellar AVMs.

MATERIALS AND METHODS

A retrospective study was performed for patients admitted for a cerebellar AVM between January 2015 and December 2019. Patients were included if (a) they presented with a ruptured or symptomatic FRA at the proximal segment of the main feeding arteries of the cerebellar AVM, (b) the cerebellar AVM did not bleed before admission, (c) the FRA was secured via PAO of the parent feeding artery, and (d) the cerebellar AVM was not intentionally managed or embolized through other feeding arteries during hospitalization.

RESULTS

Eight patients aged between 27 and 72 (48.6 ± 14.3) years were identified. Eight ruptured and symptomatic FRAs at the proximal segment of the main feeding arteries of the cerebellar AVMs underwent PAO with coils or Onyx while preserving the arteries distal to the aneurysms. All the patients achieved a favorable recovery after treatment in a follow-up ranged from 8 to 48 months. One patient experienced FRA recurrence and underwent a second PAO.

CONCLUSIONS

PAO for FRAs at the proximal segment of the main feeding arteries of cerebellar AVMs is a feasible option. This method is effective in preventing re-rupture of the FRAs and relieving the symptoms in the short term, allowing sufficient time for the patients to receive subsequent treatment.

Fully Endoscopic Microvascular Decompression for Trigeminal Neuralgia Caused by Vertebrobasilar Artery: A Case Series Review: 2-Dimensional Operative Video

BACKGROUND AND OBJECTIVE

Microvascular decompression (MVD) is the most definitive and preferred surgical treatment for trigeminal neuralgia (TN). Treatment of TN caused by the vertebrobasilar artery (VBA) has been reported to be challenging and less satisfactory in complications and recurrence. Endoscopy has been implemented to provide a comprehensive view of neurovascular conflicts and minimize brain tissue stretch injury while exploring the trigeminal nerve. However, there are few retrospective studies on the treatment of TN caused by VBA by fully endoscopic microvascular decompression (E-MVD). This article aimed to illustrate the safety and efficacy of E-MVD for TN caused by the VBA.

METHODS

Clinical data for 26 patients with TN caused by the VBA who underwent E-MVD from 2019 to 2022 were retrospectively analyzed. The characteristics of vertebrobasilar-associated TN were summarized. The safety and efficacy of E-MVD for vertebrobasilar-associated TN were estimated based on the analysis of intraoperative manipulation, postoperative symptom relief, and complications.

RESULTS

Intraoperatively, the vertebrobasilar artery was regarded as a direct offending vessel in all 26 patients with TN, the vertebral artery in 18 (69.23%) and the basilar artery in 10 (38.46%). In addition to the vertebrobasilar artery, other vessels involved included the superior cerebellar artery in 12 patients, anterior inferior cerebellar artery in 9, posterior inferior cerebellar artery in 1, and veins in 4. All patients underwent E-MVD, and TN was entirely resolved in 26 (100%) patients immediately postoperatively. During the follow-up period of 12-45 months, no recurrence or serious complications were found. There were no serious postoperative complications, such as cerebellar swelling, intracranial hemorrhage, or death.

CONCLUSION

E-MVD for vertebrobasilar-associated TN is effective and safe.

Trigeminal neuralgia caused by vertebrobasilar dolichoectasia: efficacy of stepwise decompression technique

OBJECTIVE

To explore and analyze the clinical efficacy of a stepwise decompression technique in the treatment of trigeminal neuralgia (TN) caused by vertebrobasilar dolichoectasia (VBD).

METHODS

A total of 918 patients with TN admitted to our hospital from June 2015 to May 2020 were divided into the VBD group (n = 61) and the conventional group (n = 857). The VBD group underwent stepwise decompression, while the conventional group received traditional microvascular decompression (MVD) surgery. Patients associated with the VBD were divided into direct compression (n = 14) and indirect compression group (n = 47) who had compression by other vessels in the presence of the VBD. Thereafter, the clinical data, intraoperative findings, efficacy, and complications were analyzed.

RESULTS

The curative ratio, efficacy, and recurrence rate for the VBD and conventional group were 83.6% and 89.6%, 93.4% and 95.3%, and 8.2% and 5.3%, respectively. The curative ratio, efficacy, and recurrence rate for the direct compression and indirect compression group were 85.7% and 83.0%, 92.9% and 93.6%, and 7.1% and 8.5%, separately. There were no significant differences in the curative ratio, efficacy, recurrence rate, and the incidence of complications between the two series (P > 0.05).

CONCLUSION

For TN caused by VBD, stepwise decompression not only reduces the direct compression of the trigeminal nerve by VBA but also allows identification and decompression of the actual vessels responsible for the compression. It has a good curative ratio, efficacy, and long-term pain relief rate, and it does not significantly increase the incidences of complications after surgery.

Anterior transpetrosal approach for microvascular decompression associated with the dolichoectatic vertebrobasilar artery in two patients with refractory trigeminal neuralgia: Technical note

Background

Trigeminal neuralgia (TN) due to compression from the dolichoectatic vertebrobasilar artery (DVBA) is extremely rare and difficult to treat due to its morphological characteristics. We report two cases of good transposition of DVBA and postoperative course obtained using the anterior petrosal approach and a new vasoculopexy method.

Methods

We describe two cases of microvascular decompression (MVD) for refractory TN associated with DVBA. In both cases, MVD was performed through the anterior petrosal approach. The DVBA was decompressed using a GORE-TEX sling and WECK clip in an inferomedial direction.

Results

Complete pain relief without new neurological deterioration was achieved immediately in both patients.

Conclusion

We experienced a rare condition of TN due to exclusion by the DVBA. The anterior transpetrosal approach was extremely effective in this case. This approach secured the surgical field, allowed transposition of the DVBA, and caused no perioperative complications.

Macrovascular Decompression with the Transposition Method Using Teflon Sling for Trigeminal Neuralgia Caused by the Vertebrobasilar Artery

OBJECTIVE

Complete separation of the vertebrobasilar artery (VBA) from the trigeminal nerve by microvascular decompression is technically challenging. This paper evaluates the transposition method using Teflon sling for trigeminal neuralgia (TN) caused by the VBA.

METHODS

Retrospective review of 32 patients including 2 patients with tic convulsif. Mobilization of the VBA in the anteromedial-caudal direction and repositioning of the VBA using Teflon sling and fibrin glue were performed. Pre- and postoperative pain were evaluated with the Barrow Neurological Institute (BNI) pain intensity score. Duration of surgery and postoperative neurologic complications were reviewed.

RESULTS

Preoperative BNI score ranged from III to V. Postoperative BNI score I was observed in 30 patients, II in 1 patient, and V in 1 patient as recurrence. Abducens nerve palsy was observed in 9 patients but was transient in 8. Permanent hearing loss was observed in 6 patients. Transient mild lower cranial nerve palsy was recorded in 2 patients with tic convulsif. Average surgical time was 290 minutes.

CONCLUSIONS

Our method for trigeminal neuralgia caused by VBA was very effective, but the complication rate of cranial nerve disorders was also high. A high rate of complications implied the technical difficulty of extensive vascular mobilization requiring long duration of surgery. Macrovascular decompression surgery is more descriptive of this surgery instead of microvascular decompression surgery.

Microvascular decompression for trigeminal neuralgia due to vertebrobasilar artery compression: a systematic review and meta-analysis

Trigeminal neuralgia (TN) caused by vertebrobasilar artery (VBA) compression is a rare event, reported between 2 and 6% (Linskey et al. J Neurosurg 81:1-9,1992, Vanaclocha et al.World Neurosurg 96:516-529,2016) of the time. Microvascular decompression (MVD) is advised for drug-resistant pain and, although technically challenging, is associated with an excellent outcome in current literature (Apra et al.Neurosurg Rev 40:577-582,2017, Cruccuet al. EurJ Neurol 15:1013-1028,2008, Linskey et al. J Neurosurg 81:1-9,1992). The authors performed a systematic review and meta-analysis of the literature examining the rate of MVD for trigeminal neuralgia caused by VBA compression and the post-operative outcome. The systematic search of three databases was performed for studies published between January 1990 and October 2020. Random-effects meta-analysis was used to pool the analyzed outcomes, and random-effects meta-regression was used to examine the association between the effect size and potential confounders. Funnel plot followed by Egger's linear regression was used to test publication bias. We included 9 studies, and the overall rate of TN due to VBA compression was 3.4% (95% CI 2.5-4.3%, p < 0.01, I² = 67.9%) among all MVD for TN. Immediately after surgery, 96% (p < 0.01, I² = 0%) of patients were pain-free, and at last follow-up, approximately 93% (p < 0.01, I² = 0%) of patients were classified as BNI I-II. Hearing impairment and facial numbness were the most common long-term complications ensuing MVD for VBA compression (5% and 13%, respectively). In conclusion, the surgical management of trigeminal neuralgia caused by VBA compression is associated with good outcome and low rate of post-operative complications. Further studies are needed to analyze the long-term results and the rate of pain recurrence among this population.

Location of the abducens nerve stretched by a tortuous vertebrobasilar artery in trigeminal neuralgia

BACKGROUND

Trigeminal neuralgia (TGN) caused by the vertebrobasilar artery (VBA) is uncommon. The abducens nerve root is frequently dislocated by a tortuous VBA near the trigeminal nerve root. This unusual location of the root is not well known. This study aimed to investigate the location of the stretched abducens nerve root.

METHODS

The objective is 26 patients with VBA-related TGN who underwent microvascular decompression (MVD). We retrospectively investigated the course of the abducens nerve root with magnetic resonance imaging (MRI) with three-dimensional (3D) imaging and surgical findings. The displacement of the abducens nerve root on the affected side was compared to the contralateral side.

RESULTS

The abducens nerve root was distorted by a tortuous VBA (46.2%) or the anterior inferior cerebellar artery (53.8%). The average length of the cisternal segment was stretched to 23.4 mm versus 12.4 mm on the contralateral side. The peak point of the elevated abducens nerve root was mostly located rostro-medial (65.4%) or caudo-medial (34.6%) to the neurovascular compression site of the trigeminal nerve with a mean distance of 9.1 mm. Contact with the trigeminal nerve root was observed in 7 patients (26.9%). Three-dimensional imaging was consistent with the surgical findings and useful in predicting the location of the abducens nerve root. No abducens nerve palsy was noted in our series.

CONCLUSIONS

The abducens nerve root is located near the trigeminal nerve root in VBA-related TGN. Preoperative understanding of the unusual course of the abducens nerve root contributes to avoiding accidental nerve injury during MVD.