Microvascular Decompression for Hemifacial Spasm Associated with Vertebral Artery: Biomedical Glue−Coated Teflon Sling Transposition Technique

Bridge-layered decompression technique for vertebral artery-involved hemifacial spasm: technical note

BACKGROUND

Hemifacial spasm (HFS) is most effectively treated with microvascular decompression (MVD). However, there are certain challenges in performing MVD for HFS when the vertebral artery (VA) is involved in compressing the facial nerve (VA-involved). This study aimed to introduce a "bridge-layered" decompression technique for treating patients with VA-involved HFS and to evaluate its efficacy and safety to treat patients with HFS.

METHODS

A single-center retrospective analysis was conducted on the clinical data of 62 patients with VA-involved HFS. The tortuous trunk of VA was lifted by a multi-point "bridge" decompression technique to avoid excessive traction of the cerebellum and reduce the risk of damage to the facial-acoustic nerve complex. To fully decompress all the responsible vessels, the branch vessels of VA were then isolated using the "layered" decompression technique.

RESULTS

Among the 62 patients, 59 patients were cured immediately after the surgery, two patients were delayed cured after two months, and one had occasional facial muscle twitching after the surgery. Patients were followed up for an average of 19.5 months. The long-term follow-up results showed that all patients had no recurrence of HFS during the follow-up period, and no patients developed hearing loss, facial paralysis, or other permanent neurological damage complications. Only two patients developed tinnitus after the surgery.

CONCLUSION

The "bridge-layered" decompression technique could effectively treat VA-involved HFS with satisfactory safety and a low risk of hearing loss. The technique could be used as a reference for decompression surgery for VA-involved HFS.

Meningitis after elective intracranial surgery: a systematic review and meta-analysis of prevalence

Meningitis is a potential complication of elective intracranial surgery (EIS). The prevalence of meningitis after EIS varies greatly in the literature. The objective of this study was to estimate the overall pooled prevalence of meningitis following EIS. Four databases (PubMed, Scopus, Web of Science, and Embase) were searched to identify relevant studies. Meta-analyses of proportions were used to combine data. Cochran's Q and I² statistics were used to assess and quantify heterogeneity. Additionally, several subgroup analyses were conducted to investigate the source of heterogeneity and examine differences in the prevalence based on variables such as geographical regions, income level, and meningitis type. The meta-analysis included 83 studies (30 959 patients) from 26 countries. The overall pooled prevalence of meningitis after EIS was 1.6% (95% CI 1.1-2.1), with high heterogeneity present (I² = 88%). The pooled prevalence in low- to middle-income countries and high-income countries was 2.7% (95% CI 1.6-4.1) and 1.2% (95% CI 0.8-1.7), respectively. Studies that reported only aseptic meningitis had a pooled prevalence of 3.2% (95% CI 1.3-5.8). The pooled prevalence was 2.8% (95% CI 1.5-4.5) in studies that reported only bacterial meningitis. Similar prevalence rates of meningitis were observed in the subgroups of tumor resection, microvascular decompression, and aneurysm clipping. Meningitis is a rare but not exceptional complication following EIS, with an estimated prevalence of 1.6%.

Microvascular decompression for hemifacial spasm involving the vertebral artery

Objective

Microvascular decompression (MVD) has become an accepted treatment modality for the vertebral artery (VA)–involved hemifacial spasm (HFS). The aim of this retrospective study was to evaluate clinical and surgical outcomes of HFS patients undergoing MVD and surgical and cranial nerve complications and investigate reasonable transposition procedures for two different anatomic variations of VA.

Methods

Between January and December 2018, 109 patients underwent first MVD for HFS involving VA at Nanjing Drum Tower Hospital. Based on whether the VA could be moved ventrally at the lower cranial nerves (LCNs) level, patients were assigned to Group A (movable VA, n = 72) or B (unmovable VA, n = 37), and clinical and surgical outcomes and complications on the day of post-surgery and during follow-up were assessed. All patients were followed up ranging from 17 to 24 months with a mean follow-up period of 21 months.

Results

After a mean follow-up of 21 months, the total cure rate significantly decreased in all patients compared to that achieved on the day of surgery, and Group A patients exhibited a higher cure rate versus Group B (93.1% vs. 75.7%, P = 0.015). Group B patients with unmovable VA revealed both higher incidence of surgical complications (45.9% vs. 15.3%, P = 0.001) and frequency of bilateral VA compression (27% vs. 8.3%, P = 0.009) versus Group A. No significant difference was observed in long-term cranial nerve complications.

Conclusions

VA-involved HFS can benefit from MVD strategies after preoperative assessment of VA compression. HFS patients with movable VA may receive better long-term efficacy and fewer complications. A Teflon bridge wedged between the distal VA and medulla gives rise to adequate space for decompression surgery.

Bridge technique for hemifacial spasm with vertebral artery involvement

BACKGROUND

To assess efficacy and safety of a newly developed decompression technique in microvascular decompression for hemifacial spasm (HFS) with vertebral artery (VA) involvement.

METHODS

A rigid Teflon (Bard^® PTFE Felt Pledget, USA) with the ends placed between the lower pons and the flocculus creates a free space over the root exit zone (REZ) of the facial nerve (bridge technique). The bridge technique and the conventional sling technique for VA-related neurovascular compression were compared retrospectively in 60 patients. Elapsed time for decompression, number of Teflon pieces used during the procedure, and incidences of intraoperative manipulation to the lower cranial nerves were investigated. Postoperative outcomes and complications were retrospectively compared in both techniques.

RESULTS

The time from recognition of the REZ to completion of the decompression maneuvers was significantly shorter, and fewer Teflon pieces were required in the bridge technique than in the sling technique. Lower cranial nerve manipulations were performed less in the bridge technique. Although statistical analyses revealed no significant differences in surgical outcomes except spasm-free at postoperative 1 month, the bridge technique is confirmed to provide spasm-free outcomes in the long-term without notable complications.

CONCLUSIONS

The bridge technique is a safe and effective decompression method for VA-involved HFS.

A New Application of Gelatin Sponge in the Treatment of Hemifacial Spasm by Microvascular Decompression: A Technical Note

OBJECTIVES

 Microvascular decompression (MVD) for facial nerve remains the highly efficient hemifacial spasm (HFS) treatment. Nonetheless, a variety of cases have poor response to MVD. Using Teflon plus gelatin sponge in MVD seems to be a good solution. No existing study has examined the efficacy of using Teflon combined with gelatin sponge during MVD for HFS. Therefore, this study aimed to compare the efficacy of Teflon combined with gelatin sponge in HFS patients relative to that of Teflon alone.

PATIENTS AND METHODS

 We retrospectively compared the follow-up results of patients treated with Teflon and gelatin sponge with those treated with Teflon alone previously. Six hundred and eighty-eight primary HFS patients undergoing surgery from January 2010 to January 2018 were retrospectively analyzed. Three hundred and forty-seven cases received simple Teflon, while 342 cases underwent Teflon combined with gelatin sponge.

RESULTS

 In the Teflon plus gelatin sponge group, the incidences of facial palsy and hearing loss at 1 day, 1 year, and 2 years following surgery was significantly lower than those in the simple Teflon group. Differences in the success rates between Teflon plus gelatin sponge and the simple Teflon group were not statistically significant at 1 day, 1 year, and 2 years after surgery. The recurrence rate in the Teflon plus gelatin sponge group was significantly lower at 2 years.

CONCLUSION

 For HFS patients undergoing MVD, using Teflon plus gelatin sponge can remarkably reduce the incidence of recurrence, facial palsy, and hearing loss compared with those using Teflon alone.

Efficacy and Complications of Microsurgical Neurovascular Decompression in 55 Patients With Hemifacial Spasm

OBJECTIVE

To analyze the efficacy and complications of microvascular decompression for hemifacial spasm.

STUDY DESIGN

Retrospective study.

SETTING

Regional hospital.

METHODS

Fifty-five patients with hemifacial spasm were treated by microvascular decompression. All patients with hemifacial spasm who underwent retrosigmoid microvascular decompression from May 2004 to January 2017 were included. Patients with no conflict on preoperative magnetic resonance imaging or with an alternate diagnosis were excluded.

RESULTS

The overall cure rate was 83.64%, with an average follow-up of 7.4 years. A left-sided hemifacial spasm was a healing-promoting factor (P = .01). The median healing was 0.03 months, and the mean was 6 months. The efficacy remained high in the medium term (88% at 3 years), long term (90.24% at 5 years), and very long term (90.48% at 8 years). The recurrence rate was 9.8%. Favorable criteria included a right-sided spasm (P = .01) and an average age of 62 years (P = .03). The specific complications were permanent facial palsy (3.63%), unilateral deafness (5.45%), and hearing loss (3.63%). No death was reported. Regarding the quality of life of the patients, 94.7% had a modified HFS-8 postoperative score of 0 (Hemifacial Spasm 8 Quality of Life Scale).

CONCLUSION

Microvascular decompression for hemifacial spasm is an effective and lasting technique. Its low rate of complications and the considerable quality-of-life improvement should lead surgeons to propose it to patients as soon as botulinum toxin injections become ineffective or poorly tolerated.

Transposition of Vessels for Microvascular Decompression of Posterior Fossa Cranial Nerves: Review of Literature and Intraoperative Decision-Making Scheme

INTRODUCTION

Microvascular decompression with transposition of the involved vessels provides good surgical outcomes in cases of complex and recurrent neurovascular compression syndromes. We conducted a literature review to illustrate the variations in the surgical techniques used for transposition and to provide a practical decision-making scheme for transposition of the involved vessel.

METHODS

A PubMed Medline database record search was conducted using the following algorithm ("Microvascular Decompression Surgery"[Mesh]) OR (((Microvascular) OR (Macrovascular)) AND decompression AND surgery) AND (transposition). Only articles that detailed the intraoperative techniques were included.

RESULTS

A total of 48 articles were included. The adjacent anatomical walls to which the compressing vessel can be anchored were divided into 4 groups; A: roof (tentorium cerebelli), B: anterior wall (posterior surface of petrous bone and clivus), C: posterior wall (petrosal surface of the cerebellum), and D: "no wall" required. A new decision-making scheme based on the following 2 questions was designed: 1) is the conflicting vessel amenable to transposition to a nearby wall in the cerebello-brainstem space? 2) what is the closest wall to secure the transposed vessel?

CONCLUSIONS

Transposition of the involved vessel is a valuable procedure for microvascular decompression of the posterior fossa cranial nerves. Anchoring the vessel to the adjacent anatomical wall ensures secure transposition. The proposed algorithm provides a systemic scheme to identify the optimal anatomical wall, and to determine the technique and material that can be used to anchor involved vessel. This scheme is an efficient method to inform the intraoperative decision-making process.

Spasm Freedom Following Microvascular Decompression for Hemifacial Spasm: Systematic Review and Meta-Analysis

BACKGROUND

Hemifacial spasm (HFS) is a debilitating disorder characterized by intermittent involuntary movement of muscles innervated by the facial nerve. HFS is caused by neurovascular compression along the facial nerve root exit zone and can be treated by microvascular decompression (MVD). The goal was to determine rates and predictors of spasm freedom after MVD for HFS.

METHODS

A literature search using the key terms "microvascular decompression" and "hemifacial spasm" was performed. The primary outcome variable was spasm freedom at last follow-up. Analysis was completed to evaluate for variables associated with spasm-free outcome.

RESULTS

A total of 39 studies including 6249 patients were analyzed. Overall spasm freedom rate was 90.5% (5652/6249) at a follow-up of 1.25 ± 0.04 years. There was no significant relationship between spasm freedom versus persistent spasm and age at surgery, timing of follow-up, gender, disease duration, side of disease, or vessel type. Spasm freedom was more likely after an initial surgery versus a redo MVD (odds ratio 4.16, 95% confidence interval 1.99-8.68; P < 0.01).

CONCLUSIONS

MVD works well for HFS with cure rates >90% at 1-year follow-up in 6249 patients from 39 studies. A significant predictor of long-term spasm freedom at 1 year was an initial MVD as compared to repeat MVD. The majority of published manuscripts on MVD for HFS are heterogeneous single-institutional retrospective studies. As such, a large-scale meta-analysis reporting outcome rates and evaluating significant predictors of spasm freedom provides utility in the absence of randomized controlled studies.

The efficacy of temporary clamping of V3 with a suboccipital far-lateral approach in microvascular decompression for Hemifacial spasm associated with the vertebral artery

Hemifacial spasm (HFS) is often caused by compression of the vertebral artery (VA) directly or indirectly as a result of other intervening vessels, so VA-associated HFS is difficult to treat. Recently, we have achieved good surgical outcomes using a far lateral approach and temporary clamping of V3 for VA-associated HFS. Herein, we present our method with an accompanying surgical video. From April 2018 to March 2019, 5 patients with VA-associated HFS underwent surgery, and pre-and postoperative symptoms and postoperative complications were evaluated. In the procedure, the suboccipital muscles were dissected and reflected layer by layer, and the extracranial VA (V3) was secured within the suboccipital triangle. A lateral suboccipital craniotomy followed by far lateral drilling was made to widen the surgical field from the caudolateral side. After reducing the VA flow pressure by temporary clamping of V3, the VA was transposed using a Teflon sling via two triangular space above and below the lower cranial nerves (LCNs). Causative vessels included direct VA compression in two cases and intervening vessels in three cases. The symptoms disappeared in four cases and improved satisfactorily in one case. One patient had mild hearing loss (approximately 10 dB) and hoarseness, but both improved 9 months after surgery. There was no postoperative cerebrospinal fluid leakage in any cases. A wide surgical field via the far lateral approach and the temporary clamping of V3 contributed to thorough observation of the REZ and safe and complete VA transposition.

Bioadhesives in neurosurgery: a review

OBJECTIVE

Neurosurgery presents unique surgical challenges arising from delicate neural structures, limited accessibility, and the risk of CSF leakage that can lead to CNS infections. Sutures and staples may have limited applicability in the complex anatomical constraints of cranial and spinal surgeries, especially in trauma settings when time is of the essence. Surgical bioadhesives are emerging as attractive alternatives because they avoid traumatic application methods, provide a stress-distributed fixation, and provide good cosmesis and outcomes. This article presents the history of the development of surgical bioadhesives, and is also a review of current applications of commercial surgical bioadhesives within neurosurgical procedures and the unmet clinical needs that should be addressed in bioadhesives technologies.

METHODS

A PubMed literature search was performed using the terms "(glue OR bioadhesive OR fibrin OR tisseel OR evicel OR tachosil OR cyanoacrylate OR duraseal OR bioglue) AND (neurosurgery OR spine OR spinal OR dural OR microvascular decompression OR transsphenoidal OR endovascular)." Of 2433 records screened, 168 studies were identified that described the use of bioadhesives in neurosurgical procedures.

RESULTS

The greatest number of studies describing the use of bioadhesives in neurosurgery were identified for endovascular embolization, followed by dural closure and transsphenoidal surgeries. Other common areas of application were for microvascular decompression, skin closure, peripheral nerve repair, and other novel uses. Numerous case reports were also identified describing complications associated with bioadhesive use.

CONCLUSIONS

Despite the paucity of approved indications, surgical bioadhesive use in neurosurgical procedures is prevalent. However, current bioadhesives still each have their own limitations and research is intense in the development of novel solutions.