[Microvascular decompression in hemifacial spasm: 13 cases report and review of the literature]

Clinical Application of Botulinum Toxin for Hemifacial Spasm

Hemifacial spasm is typically caused by contact between the facial nerve and blood vessels. Microvascular decompression, a treatment that directly addresses this pathogenesis, is often considered the most effective treatment method. However, surgery is not immediately performed for patients at risk from the surgical treatment, or for those with an unclear diagnosis. In these instances, Botulinum toxin injection can help manage the patient's symptoms. Numerous studies corroborate the effectiveness and safety of Botulinum toxin treatment, with large-scale studies indicating symptom control lasts, on average, around 15 weeks.

MRI measurements the linear volume of posterior cranial fossa in patients with hemifacial spasm

To explore the pathogenesis of hemifacial spasm (HFS) and the effect of posterior fossa volume on postoperative complications. The measurements of the antero-posterior diameter of foramen magnum, the length of supraocciput, the angle of tentorium cerebelli, clivus and occipital bone were performed on MRI. The data of measurements and postoperative complications were then analyzed and statistically examined. The antero-posterior diameter of the foramen magnum was smaller in HFS group (34.98 ± 2.83) mm than in control group (35.83 ± 2.67) mm (P < 0.05); The length of supraocciput was smaller in HFS group (44.67 ± 4.48) mm than in control group (45.84 ± 4.25) mm (P < 0.05); The angle of tentorium cerebelli was larger in HFS group (41.03 ± 5.01)°than in control group (37.28 ± 4.31)° (P < 0.05); The angle of clivus was smaller in HFS group (52.71 ± 6.22)° than in control group (56.39 ± 6.61)° (P < 0.05). The operation time was significantly longer in crowding group (107.90 ± 26.20) min than in non-crowding group (96.48 ± 20.52) min (P < 0.05); The incidence of postoperative facial paralysis was significantly higher in crowding group (16.19%) than in non-crowding group (7.20%) (P < 0.05); The incidence of postoperative hearing loss was significantly higher in crowding group (13.33%) than in non-crowding group (4.00%) (P < 0.05). Factors such as shorter antero-posterior diameter of foramen magnum, lower tentorium cerebelli, and shorter length of supraocciput in patients with HFS indicate the posterior fossa dysplasia and promote the occurrence of HFS. The crowding of the posterior fossa will increase the difficulty of the surgery and the incidence of postoperative facial paralysis and hearing loss.

Endoscope-assisted microsurgical retrosigmoid approach to the lateral posterior fossa: Cadaveric model and a review of literature

Background:

The advancement of endoscopic techniques in the past decade has improved the surgical management of cerebellopontine angle (CPA) tumors. Endoscope-assisted microsurgery improves the ability to evaluate the extent of resection, achieve safe tumor resection and reduce the risk of surgery-related morbidity.

Methods:

In this study, we used a cadaveric model to demonstrate a step by step endoscope-assisted microsurgery of the retrosigmoid approach to the lateral posterior fossa.

Results:

Retrosigmoid craniotomies were performed on four latex-injected cadaver heads (eight CPAs). Microsurgical exposures were performed to identify neurovascular structures in each segment. 0° and 30° rigid endoscope lenses were subsequently introduced into each corridor and views were compared in this manner. The endoscopic images were compared with the standard microscopic views to determine the degree of visualization with each technique. In each case, better visualization was provided by both the 0° and 30° endoscope lenses. Endoscopic views frequently clarified neurovascular relationships in obscured anatomic regions.

Conclusion:

Endoscope-assisted microsurgery could allow better visualization of various regions of the posterior fossa. Surgical planning for posterior fossa lesions should include consideration of this combined approach.

Improving recovery after microvascular decompression surgery for hemifacial spasm: experience from 530 cases with enhanced recovery after surgery (ERAS) protocol

OBJECTIVE

To assess the efficacy of microvascular decompression (MVD) for hemifacial spasm with an enhanced recovery after surgery (ERAS) protocol.

METHODS

984 hemifacial spasm patients who underwent MVD from Jan 2017 to Dec 2017 were analyzed. They were divided into the conventional treatment group (control; n = 453) and the later ERAS group (n = 531). The multimodal ERAS protocol consists of 23 perioperative elements. Time to feeding, mobilization, and urinary catheter removal, wound pain, postoperative nausea and vomiting (PONV), and total, preoperative, and perioperative hospital length of stay (LOS), along with outcomes and complications, were analyzed.

RESULTS

The patients in both groups had similar clinical characteristics. Patients in the ERAS group had significantly higher rates of early feeding (469 [88.5%], ERAS, vs. 183 [40.6%], control; p < 0.05), early mobilization (497 [93.7%], ERAS, vs. 215 [47.7%], control; p < 0.05), and early removal of urinary catheter (458 [86.4%], ERAS, vs. 175 [38.8%], control; p < 0.05). The ERAS group also had a significantly lower incidence of wound pain (135 [25.5%], ERAS, vs. 348 [77.2%], control) and PONV (173 [32.6%], ERAS, vs. 251 (55.7%), control) (p < 0.05) and significantly shorter preoperative (0.9 ± 0.3 d, ERAS, vs. 2.3 ± 0.6 d, control), postoperative (4.1 ± 0.4 d, ERAS, vs. 5.8 ± 0.7 d, control), and total LOS (5.2 ± 0.3 d, ERAS, vs. 8.8 ± 0.6 d, control) (p < 0.05). There was no significant difference in outcomes or surgical complication rates between two groups.

CONCLUSIONS

Implementation of the ERAS protocol for patients undergoing MVD procedures for the treatment of HFS improved the quality of perioperative care without an increase in adverse events.

The Value of Three-Dimensional Brain Volume Combined with Time-of-Flight MRA in Microvascular Decompression

OBJECTIVES

To explore the guidance value of preoperative 3-dimensional brain volume (3D-BRAVO) and 3-dimensional time-of-flight (3D-TOF) MRA scanning for microvascular decompression.

METHODS

One hundred thirteen patients treated with microvascular decompression from February 2016 to February 2018 in the First Affiliated Hospital of Dalian Medical University were retrospectively analyzed. All patients received 3D-BRAVO combined with 3D-TOF MRA sequence reconstruction before the operation. The anatomical relationship of neurovascular tissues was analyzed and compared with the results of intraoperative exploration.

RESULTS

The results of MVD showed that the number of positive cases was 108 (95.6%) on the diseased side. 3D-BRAVO combined with 3D-TOF sequence reconstruction resulted in 106 positive cases (93.8%), with a 98.1% positive coincidence rate and a 13.2% false positive rate (p < 0.05). 3D-BRAVO-TOF sequence reconstruction of trigeminal neuralgia showed a positive coincidence in 78 cases (92.8%) and for hemifacial spasm a positive coincidence was found in 27 cases (93.1%).

CONCLUSION

3D-BRAVO combined with 3D-TOF sequence reconstruction before microvascular decompression can fully evaluate the morphology, location, and anatomical relationship of lesions, which is of guidance value for clinical diagnosis and treatment.

Endoscope-assisted retrosigmoid approach in hemifacial spasm: our experience

Introduction

The use of surgical decompression of facial hemispasm due to the loop in the internal auditory canal is not always accepted due to the risk related to the surgical procedure. Currently a new surgical technique allows surgeons to work in safer conditions.

Objective

To report the results with endoscope-assisted retrosigmoid approach for facial nerve microvascular decompression in hemifacial spasm due to neurovascular conflict. The surgical technique is described.

Methods

We carried out a prospective study in a tertiary referral center observing 12 (5 male, 7 female) patients, mean age 57.5 years (range 49–71) affected by hemifacial spasm, that underwent to an endoscope assisted retrosigmoid approach for microvascular decompression. We evaluated intra-operative findings, postoperative HFS resolution and complication rates.

Results

Hemifacial spasm resolution was noticed in 9/12 (75%) cases within 24 h after surgery and in 12/12 (100%) subjects within 45 days. A significant (p < 0.001) correlation between preoperative historical duration of hemifacial spasm and postoperative recovery timing was recorded. Only 1 patient had a complication (meningitis), which resolved after intravenous antibiotics with no sequelae. No cases of cerebrospinal fluid leak, facial palsy or hearing impairment were recorded. Hemifacial spasm recurrence was noticed in the only subject where the neurovascular conflict was due to a vein within the internal auditory canal.

Conclusions

The endoscope assisted retrosigmoid approach technique offers an optimal visualization of the neurovascular conflict thorough a minimally invasive approach, thus allowing an accurate decompression of the facial nerve with low complication rates. Due to the less invasive nature, the procedure should be considered in functional surgery of the cerebellar pontine angle as hemifacial spasm treatment, specially when the procedure is performed by an otolaryngologist.

Retrospective clinical analysis of 320 cases of microvascular decompression for hemifacial spasm

To investigate effects of microvascular decompression (MVD) surgical treatment on hemifacial spasm.A retrospective analysis of 320 adult patients (95 male cases, 29.7% and 225 female cases, 70.3%) with hemifacial spasm treated by surgery was conducted between February 2007 to June 2016, with an average age of 49.3 years and average disease course of 4.9 years. All the 320 cases of patients received MVD. After surgery, all patients were followed up for an average of 2.3 years. Surgical effects were evaluated based on the patients' symptoms and signs. As this is just a retrospective study that does not involve any interventions, ethical approval was not necessary according to the rules of the hospital.All patients were followed up, no death occurred. Symptom was completely disappeared in 241 cases (75.3%), 50 cases (15.6%) improved; the total effective rate of surgery was 90.9%. No obvious changes of hemifacial spasm were happened in 29 cases (9.1%). There was no deteriorated case.MVD is one of the preferred treatments of hemifacial spasm, the intraoperative electrophysiological monitoring of abnormal muscle response signals contributes to the determination of responsible vessels and fully understanding of delayed resolution is helpful to the accuracy of surgical evaluation.

Endoscope-assisted decompression of facial nerve for treatment of hemifacial spasm

Microvascular decompression has become the sole method for a curative treatment of primary hemifacial spasm. Finding the responsible conflicting artery is not always easy as its location can be deeply situated within the cerebellopontine/medullary fissure at the facial root exit zone. Sole or additional offending vessel(s) may be at the meatus of the internal auditory canal (5% of the cases). Identifying the compressive vessel(s) and performing decompression is in most cases possible without cerebellar retraction by classical microsurgical techniques. However, in a number of patients the neurovascular conflict may be hidden in spite of the direct illumination of the operative microscope. Therefore, assistance by endoscopy can be useful and contribute as a minimally invasive approach. The author reports his own experience in a series of 553 patients operated on over the past three decades. A total of 93.6% had complete relief of their spasm (11% after repeated surgery). Relief was delayed in 20.8% of these patients. Recurrence was rare (0.3%). There was no mortality and morbidity was low: deafness occurred in 0.6%. There was no permanent postoperative facial palsy. CSF leakage amounted to 1% in the last period of surgery. In conclusion, the author advocates combining the use of both the endoscopy for exploration and the microscope for decompression.