Clinical analysis and surgical treatment of trigeminal neuralgia caused by vertebrobasilar dolichoectasia: A retrospective study

An Application of Combined Transpetrosal Approach With Microneurovascular Transposition in Recurrent Trigeminal Neuralgia Caused by Dolichoectatic Vertebral Artery

BACKGROUND

In general, the superior cerebellar artery is the most prevalent vessel that compresses the trigeminal nerve root exit zone (TGNREZ) and is responsible for trigeminal neuralgia (TGN). Nevertheless, the surgical outcome is less efficacious when the offending vessel is a dolichoectatic vertebrobasilar vessel (DVB). In addition, the potential for postprocedural adhesion and fibrosis renders recurrent TGN after prior surgery, an extremely challenging operation.

METHODS

We describe our surgical strategy and procedure that effectively resolved recurrent TGN in a patient whose offending vessel was a large DVB following standard microvascular decompression surgery. The size and nature of the offending DVB indicated that there was limited space for mobilization away from the TGNREZ, as evidenced by previous operative findings. Consequently, the patient's TGN may not be effectively treated by reoperating with the same standard lateral suboccipital approach.

RESULTS

Our surgical approach comprised the creation of an expanded area to facilitate the mobilization of the DVB from the TGNREZ, as well as the untethering of the trigeminal nerve and its subsequent mobilization from the DVB using the transposition technique.

CONCLUSIONS

A combined transpetrosal approach with microneurovascular transposition technique was selected to achieve all objectives. A case illustration with a surgical video is demonstrated.

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.

Factors associated with outcomes following microvascular decompression for the treatment of primary trigeminal neuralgia in adults: a systematic review and meta-analysis

This study aimed to evaluate pain assessment strategies and factors associated with outcomes after microvascular decompression for the treatment of primary trigeminal neuralgia in adults. We conducted a systematic review and meta-analysis of English, Spanish, and French literature. We searched three databases, PubMed, Ovid, and EBSCO, from 2010 to 2022 and selected studies including patients with primary trigeminal neuralgia, clear pain assessment, and pain outcomes. Population means and standard deviations were calculated. Studies that included factors associated with postoperative outcomes were included in the meta-analysis. A total of 995 studies involving 5673 patients with primary trigeminal neuralgia following microvascular decompression were included. Patients with arteries compressing the trigeminal nerve demonstrated optimal outcomes following microvascular decompression (odds ratio [OR]= 0.39; 95% confidence interval [CI] = 0.19-0.80; X2 = 46.31; Dof = 15; I2 = 68%; P = < 0.0001). Conversely, when comparing arterial vs venous compression of the trigeminal nerve (OR = 2.72; 95% CI = 1.16-6.38; X2 = 23.23; Dof = 10; I2 = 57%; P = 0.01), venous compression demonstrated poor outcomes after microvascular decompression. Additionally, when comparing single-vessel vs multiple-vessel compression (OR = 2.72; 95% CI = 1.18-6.25; X2 = 21.17; Dof = 9; I2 = 57%; P = 0.01), patients demonstrated unfavorable outcomes after microvascular decompression. This systematic review and meta-analysis evaluated factors associated with outcomes following microvascular decompression (MVD) for primary trigeminal neuralgia (PTN). Although MVD is an optimal treatment strategy for PTN, a gap exists in interpreting the results when considering the lack of evidence for most pain assessment strategies.

A Case With Twists and Turns: A Report of Vertebrobasilar Dolichoectasia

Vertebrobasilar dolichoectasia (VBD) is a rare anatomical abnormality of the vertebral artery system, defined as irregular expansion, elongation, and tortuosity of vertebral arteries. Anomalies of the vertebrobasilar artery can have a wide variety of clinical presentations, ranging from simple headaches to debilitating strokes. We present the case of an atypical presentation of VBD which mimicked trigeminal neuralgia by compressing the trigeminal nerve. There are currently no guidelines concerning the management of VBD, nor is there evidence of a definitive cure. This case invoked discussions among the medical team as to whether management should be medically or surgically focused, as well as long-term outcomes for patients with VBD. The superiority of medical versus surgical treatment of this issue is still a debated topic. This patient trialed medical management with dexamethasone and carbamazepine with no improvement in symptoms. He then underwent surgical gamma knife treatment but even this invasive measure was unsuccessful at relieving his symptoms. We hope that by presenting this case, we can display how the therapies available for VBD are limited and often unsuccessful in relieving the disease burden in patients with VBD.

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.

Efficacy and safety of computed tomography-guided percutaneous balloon compression for trigeminal neuralgia secondary to vertebrobasilar dolichoectasia

Percutaneous balloon compression (PBC) of Gasserian ganglion has been popularly used to treat trigeminal neuralgia (TN), one of the most painful syndromes in human experience. Vertebrobasilar dolichoectasia (VBD) is a rare cause of TN and remains challenging to treat. To our knowledge, no study has reported the therapeutic outcome of PBC for VBD-related TN (VBD-TN). In this retrospective study, we collected and analyzed the medical records of all patients undergoing PBC procedure for VBD-TN under the guidance of CT plus three-dimensional reconstruction at the Pain Management Center of Beijing Tiantan Hospital from January 2017 to December 2022. All 23 patients (15 men and 8 women) had a substantial pain relief as modified Barrow Neurological Institute (BNI) I-IIIb immediately after procedure. The follow-up duration ranged from 2 to 63 months, and at the last follow-up visit, only 3 patients (13%) relapsed (BNI IV-V). The cumulative recurrence-free survival was 95%, 87%, and 74% within 1, 3, and 5 years, respectively. Patients' reported satisfactory rate was 100% as Likert scale 4-5 throughout the whole follow-up period, with no severe complications occurring. Our data revealed promising efficacy and safety of PBC procedure for treatment of VBD-TN, thus suggesting a valuable option for pain control in these rare cases of TN. However, there has been no supporting evidence that PBC treatment is a preferred option to other treatments.

Contact-free transposition and interposition techniques for trigeminal neuralgia: a systematic review

INTRODUCTION

Surgical treatment for trigeminal neuralgia (TGN), by means of interposition of material between nerve and offending vessel, has been shown to be highly efficient. In recent years, treatment by means of vessel transposition has become more frequent, as in singular cases of recurrence, nerval reactions towards interposed material have been noted. In this review we research the classic microvascular decompression (MVD) techniques (interposition) as well as the more recent transposition and their effectiveness, considering patient outcomes as well as complications and recurrences.

EVIDENCE ACQUISITION

We searched online databases MEDLINE and LIVIVO, using key words trigeminal neuralgia AND transposition/ AND sling/ AND non compressive technique/ AND microvascular decompression.

EVIDENCE SYNTHESIS

We included 8 studies for transposition and 20 studies for the interposition, combining for 2045 patients (302 for transposition and 1743 for interposition). 96.1% of patients in the transposition and 93.1% in the interposition group reported a positive outcome immediately postoperatively. At follow-up, 87.4% in the transposition group (follow-up 51.2 months) and 87.9% of patients in the interposition group (follow-up 36.5 months), reported a positive outcome. 16.2% of patients in the transposition and 13.1% in the interposition group had postoperative complications. Recurrence was reported in 5.6% of patients treated with transposition and 2.3% of patients treated with interposition.

CONCLUSIONS

Transposition presents similar results concerning short- and long-term patient satisfaction for treatment of TGN as well as similar numbers of complications of recurrences as interposition. Yet, current evidence is restricted to a few retrospective studies, thus, evidence is limited so far.

Postoperative hemorrhage after biomedical glue sling technique in microvascular decompression for vertebrobasilar artery-associated cranial nerve diseases: A retrospective study of 14 cases

Background

The biomedical glue sling technique is a convenient and effective method for vertebrobasilar artery-associated cranial nerve diseases but postoperative hemorrhage is poorly understood.

Methods

We retrospectively reviewed 14 of 1157 patients associated with cranial nerve diseases who were subjected to the biomedical glue sling technique in microvascular decompression at our hospital from January 2015 to January 2020.

Results

There were 14 patients with cranial nerve diseases included in this study. A clinical diagnosis of postoperative hemorrhage was made after an average of 41.75 h (ranging between 0.5 and 95 h). A cerebellopontine angle hemorrhage was presented in 5 patients, while basal ganglia hemorrhage was observed in 2 patients. Both a cerebellopontine angle and brainstem hemorrhage was seen in 1 patient. Distal supratentorial subdural hemorrhage was recorded in 6 patients. The correlation coefficient was -0.1601 (p = 0.7094) between the standard deviation of systolic blood pressure and the Hemphill Score, -0.2422 (p = 0.5633) between the coefficient of variation of systolic blood pressure and the Hemphill Score, and -0.0272 (p = 0.9489) between the range of systolic blood pressure and the Hemphill Score.

Conclusions

The incidence of postoperative hemorrhage after MVD with the biomedical glue sling technique is higher than with traditional MVD and most cases have a favorable prognosis. Postoperative symptoms are the main area of concern and changes in symptoms usually suggest the occurrence of hemorrhage. Several factors, including surgical procedures, the release of CSF, and blood pressure might be associated with hemorrhaging. We still believe such a technique is an efficient approach to treating complicated cranial nerve diseases.

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 by interposition method for treatment of trigeminal neuralgia due to vertebrobasilar dolichoectasia: a retrospective single-center study

Trigeminal neuralgia (TN) due to vertebrobasilar dolichoectasia (VBD) is a rare disease that can be challenging to treat. The objectives of this study are to investigate the characteristics of patients with TN due to VBD and to analyze the efficacy of microvascular decompression (MVD) by the interposition method for treatment of the condition. From 2010 until 2020, the data of 30 patients with TN due to VBD who were treated with MVD by the interposition method were analyzed retrospectively. The characteristics of the patients were compared with those of patients with non-VBD TN (n = 815). Kaplan-Meier survival analysis was performed to determine pain-free survival. The 30 patients (21 males, 9 females; mean age, 63.03 years) accounted for 3.55% of all patients with TN during the study period. In 30 patients, the offending vessel was the basilar artery (BA) in 1 patient, the vertebral artery (VA) in 6 patients, the VA plus the superior cerebellar artery (SCA) in 6 patients, the VA plus the anterior inferior cerebellar artery (AICA) in 12 patients, and the VA + SCA + AICA in 5 patients. Compared to non-VBD TN patients, those with TN due to VBD were significantly more likely to be male, to have TN of the left side, and to have hypertension (all P < 0.001). Mean age at surgery (P = 0.057) and symptom duration (P = 0.308) were comparable between the two groups. All 30 patients had immediate relief of facial pain after MVD and could stop medication. There were no postoperative complications. Over mean follow-up of 76.67 months, 3 patients had recurrence. The mean duration of pain-free survival was 70.77 months. In conclusions, TN due to VBD appears to be more likely in males, in those with hypertension, and to involve the left side. The interposition method performed by experienced and skilled neurosurgeons is a safe and effective treatment for TN due to VBD. Further studies are needed to analyze the associated long-term results and the pain recurrence rate among this special population.

Comparison of Microvascular Decompression and Two Isocenters Gamma Knife for the Treatment of Trigeminal Neuralgia Caused by Vertebrobasilar Dolichoectasia

Background: Vertebrobasilar dolichoectasia (VBD) is one of the rare causes of trigeminal neuralgia (TN). The common surgical treatments for patients with TN caused by VBD (VBD-TN) are microvascular decompression (MVD) and Gamma Knife radiosurgery (GKRS). However, the therapeutic effects of the two methods have not been clinically compared, so this study was performed to evaluate the treatment outcomes of MVD and GKRS for patients with VBD-TN.

Methods: The retrospective study was performed from March 2011 to March 2019 in Wuhan Union Hospital. A total of 80 patients diagnosed with VBD-TN were included in this study, and they were divided into the MVD group (n = 46) and GKRS group (n = 34) according to the surgical methods. The imaging data, intraoperative findings, treatment outcomes, and complications of the two groups were analyzed and compared. Meanwhile, the influencing factors of the treatment effect are also explored on the two groups.

Results: Patients who underwent MVD were younger than patients who underwent GKRS (median ages were 61.1 and 65.4 years old, respectively, p = 0.03). The median follow-up was 61.1 months for the MVD group and 56.8 months for the GKRS group. The favorable outcomes [Barrow Neurological Institute (BNI) pain score, BNI scores I–II] occurred in 97.8% of patients treated with MVD and in 78.9% of patients treated with GKRS (p = 0.009). The favorable outcomes in the percentage of patients after MVD 1, 3, 5, and 7 years were 95.7, 85.1, 74.2, and 74.2%, respectively, whereas the corresponding percentages after GKRS were 76.5, 66.2, 56.6, and 47.2%, respectively (p = 0.031). The postoperative complications (except facial numbness) in the MVD group were higher than those in the GKRS group (p = 0.036), but the incidence of new and worsening facial numbness was lower in the GKRS group (p < 0.001).

Conclusions: MVD is superior to GKRS in obtaining and maintaining favorable outcomes for patients with VBD-TN, but it also comes with more complications other than facial numbness. Thus, the treatment program can be tailored to a patient's unique condition and wishes.

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.

Comparative Analysis of Trigeminal Neuralgia Caused by Sole Arterial and Venous Compression: Clinical Features and Surgical Outcomes From 222 Cases

Background: Compared with trigeminal neuralgia (TN) caused by arterial neurovascular conflict (NVC), the clinical characteristics and managements for TN with venous NVC are not well-established. This study aims to comparatively summarize the clinical features and surgical outcomes of microvascular decompression (MVD) for patients with TN caused by sole arterial and venous compression, with a particular focus on the morphological features of posterior cranial fossa (PCF).

Methods: A total of 222 patients with TN caused by sole arterial NVC (188/84.7%) and venous NVC (34/15.3%) underwent MVD in our department from January 2014 to December 2018. The patient data were analyzed retrospectively. Particularly, we focused on the potential impact of PCF on surgical outcomes.

Results: Compared with arterial NVC, V3 branch of the trigeminal nerve was more frequently involved in venous NVC (p = 0.009). The most common compression site was root entry zone for arterial NVC (68.6%) and midcisternal segment for venous NVC (76.5%) (p < 0.001). No serious post-operative complication was observed in the two groups. Both short- and long-term outcomes were relatively worse in venous NVC cases compared with arterial NVC cases (p = 0.001 and p = 0.030, respectively); and a dominantly higher rate of delayed cure was demonstrated in venous NVC cases (p < 0.001). TN patients with venous NVC revealed a more flat-shaped PCF than those with arterial NVC. Moreover, flat-shaped PCF morphometry was negatively correlated with surgical outcomes of TN patients with arterial NVC, but not with those of venous NVC cases.

Conclusions: MVD is an effective and safe treatment for patients with TN caused by either arterial or venous NVC. Patients with a more flat-shaped PCF might be vulnerable to venous compression. Our study demonstrated that PCF morphometry only affected the surgical outcomes of patients with TN caused by arterial NVC, but not the outcomes of those with venous NVC.

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

BACKGROUND

Separation of the vertebrobasilar artery (VBA) from the trigeminal nerve root in microvascular decompression (MVD) is technically challenging. This study aimed to review the clinical features of VBA involvement in trigeminal neuralgia and evaluate surgical decompression techniques in the long term.

METHODS

We retrospectively reviewed the surgical outcomes of 26 patients (4.4%) with VBA involvement in 585 consecutive MVDs for TGN using a Teflon roll for repositioning the VBA. The final operative status of the nerve decompression was categorized into two groups: the separation group and the contact group. Separation of the VBA from the nerve root was completed in 13 patients in the separation group, and slight vascular contact remained in the remaining 13 patients of the contact group. The clinical features of VBA-related TGN were investigated and the operative results were analyzed.

RESULTS

Multiple arteries are involved in neurovascular compression (NVC) in most cases. The anterior inferior cerebellar artery was the most common concomitant artery (69%). The site of the NVC varies from the root entry zone to the distal portion of the root. All patients were pain-free immediately after surgery and maintained medication-free status during the follow-up period, except for one patient (3.8%) who had recurrent facial pain 8 years after surgery. Postoperative facial numbness was observed in six patients (23%). Of these, one patient showed improvement within 3 months and the other five patients had persistent facial numbness (19.2%). Other neurological deficits include one dry eye, one diplopia due to trochlear nerve palsy, two decreased hearing (< 50 db), two facial weaknesses, and two cerebellar ataxia. Although most of them were transient, one dry eye, two hearing impairments, and one cerebellar ataxia became persistent deficits. Statistical analyses revealed no difference in surgical efficacy or complications in the long term between the two groups.

CONCLUSIONS

Slightly remaining vascular contact does not affect pain relief in the long term. Our study indicated that once the tense trigeminal nerve is loosened, further attempts to mobilize the VBA are not necessary.

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.

Microvascular decompression for trigeminal neuralgia caused by vertebrobasilar dolichoectasia: interposition technique versus transposition technique

BACKGROUND

Various techniques of microvascular decompression have been proposed for trigeminal neuralgia (TN) caused by vertebrobasilar dolichoectasia (VBD) with two main modalities: interposition and transposition. This retrospective study compares the outcomes of two techniques belonging to different modalities for VBD-associated TN.

METHODS

From January 2011 to April 2017, 39 patients underwent MVD for VBD-associated TN. The transposition method chosen was the biomedical glue sling technique. Patients were divided into the interposition group (n = 16) and the transposition group (n = 23). The radiologic data, intraoperative findings, complications, and outcomes were analyzed.

RESULTS

The 1-, 3-, and 5-year pain-free (BNI class I) maintenance rates were 100.0, 91.1, and 91.1%, respectively, in the transposition group and 87.5, 74.5, and 58.7% in the interposition group (p = 0.032). Postoperative complications were similar in both groups, but there was a trend for higher incidence of postoperative facial hypoesthesia using the interposition technique (p = 0.06).

CONCLUSION

In cases of VBD-associated TN, the transposition technique using biomedical glue was superior to the traditional interposition technique in maintaining a pain-free status, with no increase in the incidence of complication.

Vestibulocochlear Symptoms Caused by Vertebrobasilar Dolichoectasia

OBJECTIVES

Vertebrobasilar dolichoectasia (VBD), an elongation and distension of vertebrobasilar artery, may present with cranial nerve symptoms due to nerve root compression. The objectives of this study are to summarize vestibulocochlear manifestations in subjects with VBD through a case series and to discuss the needs of thorough oto-neurotologic evaluation in VBD subjects before selecting treatment modalities.

METHODS

Four VBD subjects with vestibulocochlear manifestations were reviewed retrospectively. VBD was confirmed by either brain or internal auditory canal magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). Patient information, medical history, MRI/MRA findings, and audiometry or vestibular function tests were reviewed according to patient's specific symptom.

RESULTS

Of the four subjects, three presented with ipsilesional sensorineural hearing loss (SNHL), three with paroxysmal recurrent vertigo, and two with typewriter tinnitus. The MRI/MRA of the four subjects revealed unilateral VBD with neurovascular compression of cisternal segment or the brainstem causing displacement, angulation, or deformity of the cranial nerve VII or VIII that corresponded to the symptoms.

CONCLUSION

Vestibulocochlear symptoms such as SNHL, recurrent paroxysmal vertigo, or typewriter tinnitus can be precipitated from a neurovascular compression of the vestibulocochlear nerve by VBD. Because proper medical or surgical treatments may stop the disease progression or improve audio-vestibular symptoms in subjects with VBD, a high index of suspicion and meticulous radiologic evaluation are needed when vestibulocochlear symptoms are not otherwise explainable, and if VBD is confirmed to cause audiovestibular manifestation, a thorough oto-neurotologic evaluation should be performed before initial treatment.

Treatment Outcomes in Trigeminal Neuralgia-A Systematic Review of Domains, Dimensions and Measures

BACKGROUND

Trigeminal neuralgia (TN) is a painful disorder characterized by sudden electric shock-like pain. It is a rare condition for which multiple treatments are available, including medical and surgical. The best treatment option is yet to be defined, and this is related to the lack of definition in the treatment outcomes and outcome measures. The aim of this systematic review was to summarize all the outcomes and outcomes measures that have been published to date and highlight variability in their use.

METHODS

We have conducted a literature search using a wide range of databases (1946-2019 for medical and 2008-2019 for surgical treatment), for all intervention studies in TN. Four hundred and sixty-seven studies were selected for data extraction on TN classification, data collection method, intervention, and treatment outcomes mapped to the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT guidelines).

RESULTS

Most studies collected data on pain (n = 459) and side effects (n = 386) domains; however, very few collected data on the impact of treatment on physical (n = 46) and emotional functioning (n = 17) and on patient satisfaction (n = 35). There was high variability on outcome measures used for pain relief (n = 10), pain intensity (n = 9), and frequency of pain episodes (n = 3).

CONCLUSIONS

A clear definition of what are the important outcomes for patients with TN is essential. The choice of standardized outcome measures allowing for consistent reporting in TN treatment will allow for comparison of studies and facilitate treatment choice for patients and clinicians thus, improving health outcomes and reducing health care cost.

Pain Outcomes Following Microvascular Decompression for Drug-Resistant Trigeminal Neuralgia: A Systematic Review and Meta-Analysis

BACKGROUND

Microvascular decompression (MVD) is a potentially curative surgery for drug-resistant trigeminal neuralgia (TN). Predictors of pain freedom after MVD are not fully understood.

OBJECTIVE

To describe rates and predictors for pain freedom following MVD.

METHODS

Using preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, PubMed, Cochrane Library, and Scopus were queried for primary studies examining pain outcomes after MVD for TN published between 1988 and March 2018. Potential biases were assessed for included studies. Pain freedom (ie, Barrow Neurological Institute score of 1) at last follow-up was the primary outcome measure. Variables associated with pain freedom on preliminary analysis underwent formal meta-analysis. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for possible predictors.

RESULTS

Outcome data were analyzed for 3897 patients from 46 studies (7 prospective, 39 retrospective). Overall, 76.0% of patients achieved pain freedom after MVD with a mean follow-up of 1.7 ± 1.3 (standard deviation) yr. Predictors of pain freedom on meta-analysis using random effects models included (1) disease duration ≤5 yr (OR = 2.06, 95% CI = 1.08-3.95); (2) arterial compression over venous or other (OR = 3.35, 95% CI = 1.91-5.88); (3) superior cerebellar artery involvement (OR = 2.02, 95% CI = 1.02-4.03), and (4) type 1 Burchiel classification (OR = 2.49, 95% CI = 1.32-4.67).

CONCLUSION

Approximately three-quarters of patients with drug-resistant TN achieve pain freedom after MVD. Shorter disease duration, arterial compression, and type 1 Burchiel classification may predict more favorable outcome. These results may improve patient selection and provider expectations.

Kawase Approach for Dolichoectactic Basilar Artery Macrovascular Decompression in a Patient With Trigeminal Neuralgia: Case Report

BACKGROUND AND IMPORTANCE

Trigeminal neuralgia (TN) secondary to a dolichoectatic basilar artery (DBA) is an extremely rare phenomenon. The Kawase approach for macrovascular decompression of this rare pathology been used rarely.

CLINICAL PRESENTATION

This report describes macrovascular decompression and basilar artery transposition in a 69-yr-old male presenting with progressively worsening left-sided typical TN secondary to a DBA compression. The DBA was successfully decompressed off of the trigeminal nerve via a pterional craniotomy and anterior petrosectomy. The patient had immediate improvement in TN symptoms postoperatively. The patient remained symptom free with nonbothersome facial numbness in the V3 segment at 8-mo postoperative follow-up in clinic. The patient suffered a sixth nerve palsy following surgery, which was later corrected by strabismus surgery. The natural history and epidemiology of TN, results of macrovascular decompression secondary to DBA compression via a traditional suboccipital retrosigmoid approach, and potential advantages of the Kawase approach are also discussed.

CONCLUSION

The macrovascular decompression strategy succeeded because the compressive force was applied by the DBA to the nerve in a superolateral direction, and the decompressive sling pulled the DBA away from the nerve in an inferomedial direction. The working space and access to the clival dura through the Kawase approach allowed proper corrective pull with a sling.

Successive occurrence of vertebrobasilar dolichectasia induced trigeminal neuralgia, vestibular paroxysmia and hemifacial spasm: A case report

RATIONALE

Study reported an extremely rare case of trigeminal neuralgia, vestibular paroxysmia, and hemifacial spasm successively occurring in a patient with vertebrobasilar dolichoectasia (VBD).

PATIENT CONCERNS

A 66-year-old female patient presented with episodic vertigo for 20 days before she was admitted to our hospital. Vertigo suddenly occurred when the patient rotated her head 20 days ago, the symptoms of vertigo were improved after continuous 1 to 3 seconds, and similar symptoms were repeated in sleep and rest, with a frequency of 30 to 40 times per day. The patient had a history of hypertension with poor blood pressure control for more than 20 years.

DIAGNOSES

The final diagnosis was vertebrobasilar dolichectasia, right trigeminal neuralgia, and vestibular paroxysmia.

INTERVENTIONS

Vitamin B1 (10 mg), methylcobalamin (0.5 mg), and carbamazepine (0.1 g) were given orally 3 times a day to relieve the symptoms.

OUTCOMES

On the seventh day of drug treatment, the symptoms of paroxysmal vertigo and trigeminal neuralgia were completely relieved, but occasional episodes occurred during the follow-up period. Five months after discharge, right hemifacial spasm appeared in the patient, which did not affect the quality of life of the patient, so the patient did not choose further treatment. Six months after discharge, the patient was lost to follow-up.

LESSONS

Comprehensive treatment to control VBD risk factors, delay the progression of VBD, and improve clinical symptoms may have a better effect on such patients. However, further research is needed.