Surgical effect and electrophysiological study of patients with hemifacial spasm treated with botulinum toxin or acupuncture before microvascular decompression

Decompression Surgery in Elderly Patients with Hemifacial Spasm Refractory to Botulinum Toxin

BACKGROUND

Botulinum toxin is an effective treatment for hemifacial spasm in elderly patients. However, some patients do not tolerate the side effects and frequency of botulinum toxin treatments.

OBJECTIVES

The purpose of this study was to evaluate the characteristics and outcomes of a cohort of elderly patients referred by neurologists for surgical decompression of the facial nerve following botulinum toxin treatment.

METHODS

In a prospective cohort study, logistic regression was used to detect potential predictors of spasm-freedom after surgical decompression of the facial nerve in elderly patients that received ≤8 and >8 botulinum toxin treatments for hemifacial spasm before surgery. Age, sex, side, preoperative symptom duration, and preoperative botulinum toxin treatment were assessed as potential predictors of spasm-freedom at last follow-up.

RESULTS

Of 76 elderly patients with hemifacial spasm treated with botulinum toxin and microvascular decompression, with at least 2-years of follow-up (median, 44.5 months), 84.2% were spasm-free at last follow-up. Age (P = 0.38), sex (P = 0.59), side (P = 0.15), preoperative symptom duration (P = 0.7), and number of preoperative botulinum toxin treatments (P = 0.3) were not predictors of long-term spasm-freedom. Permanent ipsilateral hearing loss was the most frequent complication (3.9%).

CONCLUSION

This study provides evidence that elderly patients can undergo botulinum toxin treatment for hemifacial spasm without compromising their likelihood of achieving spasm-freedom with future surgical decompression. Therefore, surgical decompression of the facial nerve is an effective therapy for elderly patients with hemifacial spasm refractory to botulinum toxin.

Intraoperative findings of abnormal muscle response for hemifacial spasm following botulinum neurotoxin treatment

OBJECTIVE

This study aimed to investigate the effect of preoperative botulinum toxin (BTX) injection on intraoperative abnormal muscle response (AMR) in patients with hemifacial spasm (HFS).

METHODS

A total of 104 patients (32 men, 72 women) who underwent microvascular decompression (MVD) for HFS were included in this study. A total of 62 patients without and 42 patients with preoperative BTX treatments were assigned to group A and group B, respectively. AMR recordings were obtained from the orbicularis oculi and mentalis muscles by stimulation of the marginal mandibular branch and zygomatic branch of the facial nerve, respectively. The intraoperative AMR monitoring findings and therapeutic effects were compared between groups A and B.

RESULTS

The rates of the patients with unavailable AMRs recorded from the orbicularis oculi muscles in group B (38.1%) were significantly higher than those in group A (14.5%, p = 0.006). Moreover, in cases with over 4 times BTX injection, the recordings of AMR from the orbicularis oculi muscles were poorer than the cases with less BTX injection (p = 0.001). There were no significant differences in the rates of the patients with unavailable AMRs recorded from the mentalis muscles between the two groups. There were no significant differences in the surgical results obtained between the two groups.

CONCLUSIONS

Preoperative BTX injections should be less than 4 times to ensure effective AMR monitoring. MVD using AMR monitoring is useful for patients with HFS who were previously treated by BTX as well as those who were not treated.

Hemifacial Spasm: Comparison of Results between Patients Older and Younger than 70 Years Operated on with Microvascular Decompression

OBJECTIVE

 The aim of the present study was to evaluate the efficacy and safety of microvascular decompression (MVD) for primary hemifacial spasm (HFS) in patients aged ≥70 years and to compare the outcome with a control cohort of younger patients(<70 years).

METHODS

 In this retrospective study, subjects were divided into two groups: an elderly group (patients who were ≥70 years) and a younger group. We compared demographic and clinical data, surgical outcome, MVD-related complications, and duration of operation and hospitalization after MVD between the two groups.

RESULTS

 At a mean follow-up of 32 ± 4.2 months, 188 elderly patients (90.4%) reported an effective outcome without need for any medication versus 379 (91.1%) of the younger cohort. There was no mortality in both cohorts. The prevalence of delayed facial palsy was 4.8% in the elderly group and 4.1% in the younger group. One (0.5%) patient in the elderly group and 3 (0.7%) patients in the younger group suffered cerebrospinal fluid (CSF) leakage. There was no significant difference between the two groups in terms of MVD-related complications, such as delayed facial palsy, hearing impairment, CSF leakage, and hematoma.

CONCLUSIONS

 MVD is an effective treatment option in elderly patients with HFS as well as in younger patients. Age itself seems to be no relevant contraindication or, alternatively, risk factor regarding MVD.

Facial root entry/exit zone contact in microvascular decompression for hemifacial spasm: a historical control study

Background

Microvascular decompression (MVD) surgery is recognized as an effective treatment for hemifacial spasm (HFS). In MVD surgery, biocompatible materials are usually implanted in situ at the neurovascular conflict site in contact with the offending vessel and the facial root entry/exit zone (REZ). Another procedure of implanting the materials between the responsible vessel and the supraolivary fossa without REZ contact has also been applied. However, it is unclear whether there are any differences between these 2 procedures (REZ-contact procedure vs. REZ-non-contact procedure). Therefore, the aim of the present study was to investigate the effect of the placement of implants (contacting or not contacting the facial REZ) on surgical operations and outcomes

Methods

A historical control study was performed. Clinical data of HFS patients who underwent MVD between December 2016 and November 2018 were reviewed and categorized into 1 group with the REZ-contact procedure or another group with the REZ-non-contact procedure according to the decompression strategy they received. Clinical demographics, postoperative outcomes, and complications were collected and compared between the two groups.

Results

Not all patients are suitable for REZ-non-contact decompression. A total of 205 patients were enrolled: 112 in the REZ-contact group and 93 in the REZ-non-contact group. In the early postoperative period, the complete cure rate in the REZ-non-contact group was significantly higher than that in the REZ-contact group. The reappearance and partial relief rates in the REZ-contact group were significantly higher than those in the REZ-non-contact group. The incidence of short-term neurological complications, especially hearing loss and transient facial palsy, was lower in the REZ-non-contact group (P=0.043). But for long-term follow-up of >1 year, there was no significant difference between the two groups in either curative effects or neurological complications. The operating time for REZ-non-contact decompression was relatively longer than for REZ-contact decompression (P=0.000). An unexpected subdural hemorrhage occurred in the REZ-non-contact group.

Conclusions

REZ-non-contact decompression procedure showed superiority only in short-term postoperative outcomes. Given its limitations and potential risks, the REZ-non-contact procedure can be used as an alternative individualized strategy in MVD, and there is no need to pursue REZ-non-contact during the decompression.