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Background: Among the symptoms seen in idiopathic intracranial hypertension (IIH), hemifacial spasm (HFS) is rare. Orthostatic-induced HFS preceding lumbar puncture (LP) is previously unreported. We treated two patients with unusual IIH presentations. This case series reviews the few reports of HFS in IIH and proposes a mechanism for spasm occurrence., Methods: Case 1: A woman in her mid-40s with previously controlled IIH developed daily headache, pulsatile tinnitus, right-sided trigeminal paresthesia, and right-sided HFS. The latter 2 symptoms occurred exclusively when moving from a sitting to a standing position. Imaging was unremarkable; opening pressure (OP) on LP was 46 cmH 2 O with normal cerebrospinal fluid (CSF) components. Case 2: A woman in her late 40s presented with severe daily headache, pulsatile tinnitus, and left-sided HFS following weight gain. Imaging was unremarkable; OP on LP was 32 cmH 2 O with normal CSF components., Results: HFS episodes persisted following LP in both patients. Increasing and initiating acetazolamide, respectively, resolved all symptoms., Conclusions: Earlier suggested mechanisms of HFS are based on elevated intracranial pressure (ICP) shifting the facial nerve into proximity of a vascular structure. HFS appearing upon standing and continuing after LP, and thus a lower ICP, contradicts this. We propose a mechanism based on the degree of ICP change. This theory is grounded in the lack of intracranial compliance in IIH, wherein substantial pressure changes occur following small volume changes., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 by North American Neuro-Ophthalmology Society.)

Microvascular decompression (MVD) has proven efficacy in trigeminal neuralgia (TN) and hemifacial spasm (HFS). This study utilized computational fluid dynamics (CFD) to investigate the impact of MVD on wall shear stress (WSS) of responsible arteries (RAs) at the neurovascular contact (NVC). A total of 21 cases (10 TN, 11 HFS) were analyzed, involving RAs at NVC validated through intraoperative photographs. Hemodynamic parameters (WSS, vessel diameter, flow rate, pressure drop) was calculated using CFD for the RAs based on 3D silent-magnetic resonance angiograms. The NVC was segmented into NVC-proximal, NVC-site, and NVC-distal portions using simulated 3D CFD images that correlated with surgical observations. WSS ratios of NVC-site to NVC-proximal (NVC-site/proximal) was calculated both before and after MVD. Prior to MVD, WSS in the RA at the NVC displayed a peaked curve with a maximum at NVC-site; however, post MVD, it presented a smooth curve without peaks. The WSS ratio exhibited a significant decrease after MVD. The impact of MVD on WSS of RAs at NVC was evaluated in both TN and HFS cases. Analyzing the hemodynamics of RAs through CFD and identifying WSS peaks at NVC portions before MVD provided a more detailed and localized understanding of the morphologically depicted NVC., (© 2024. The Author(s).)

Purpose: To investigate the effect of botulinum toxin-A (BTX-A) treatment on corneal topography, ocular biometry and keratometry in patients with benign essential blepharospasm (BEB) and hemifacial spasm (HFS)., Methods: This study comprised 66 eyes of 33 patients with BEB and 5 eyes of 5 patients with HFS who underwent BTX-A injections consecutively. Refractive error values, tear break-up time (TBUT), corneal topography [corneal power of flat axis (K1) and steep axis (K2), mean corneal power (Km), corneal astigmatism (K2-K1)] and ocular optical biometry [axial length (AL), anterior chamber depth (ACD)] were recorded before BTX-A treatment and 1 month after BTX-A treatment. The researchers calculated the expected emmetropic intraocular lens power (emm-IOL) using the SRK-T, Holladay, Hoffer-Q and Haigis formulas at each examination., Results: K1 (43.48 ± 2.02 vs. 43.57 ± 2.08, p = 0.036), Km (43.91 ± 1.99 vs. 43.99 ± 2.06, p = 0.024) and ACD (3.22 (2.77-3.76) vs. 3.41 (2.99-4.02), p < 0.001) values were found to be significantly higher. The expected emm-IOL according to the SRK-T (21.04 ± 1.6 vs. 20.93 ± 1.6, p = 0.048), Holladay (21.05 ± 1.6 vs. 20.91 ± 1.62, p = 0.037) and Hoffer-Q (21.08 ± 1.65 vs. 20.94 ± 1.68, p = 0.038) decreased significantly. The expected emm-IOL according to the Haigis formula slightly decreased, but it was not significant (p = 0.386). Additionally, TBUT was found to be significantly lower (p < 0.001) after BTX-A injection. Other parameters were not statistically significant (p > 0.05)., Conclusions: Our study is the first in the literature to compare optic biometry data and intraocular lens power calculation formulas before and after BTX-A injection in eyes with BEB and HFS. BTX-A injection could play an important role in changing the keratometric and ACD values. It should be considered that IOL power calculations that might be unpredictable due to blepharospasm, so repeated measurements and especially measurements after releasing the spasm with BTX-A injections, are necessary in BEB and HFS., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Blink reflex (BR) is an oligosynaptic reflex that involves the ophthalmic branch of the trigeminal nerve (TN), ipsilateral main sensory and trigeminospinal nuclei, bilateral facial nuclei, and the facial nerves (FNs). Theoretically, as BR tests the function of both TN and FNs simultaneously, it is an ideal tool for monitoring the status of TN and FNs during skull base surgeries. Nevertheless, it has been used only recently in surgeries as the use of anesthesia limits its use., Methods: For this systematic review, 2 authors input the search terms [(Blink Reflex) AND (Intraoperative Neuromonitoring OR Neuro Intraoperative Monitoring OR Intraoperative OR NIOM OR IONM) AND (skull base surgery OR Facial Nerve OR Trigeminal Nerve OR Microvascular Decompression OR Hemifacial Spasm)] in MEDLINE through its PubMed interface and other search engines. Articles that fulfilled the inclusion and exclusion criteria were obtained and scrutinized., Results: Seven observational articles with a total of 437 participants were included. All 5 studies that described the use of BR in FN surgery noted that intraoperative BR is beneficial, safe, sensitive, specific, and predictive of outcomes, while 2 articles describing patients with trigeminal neuralgia recommended use of BR in microvascular decompression of TN., Conclusions: Intraoperative BR is a sensitive, specific, and safe monitoring technique that has good predictability of facial paresis and paresthesia among patients undergoing MVD for trigeminal neuralgia and primary hemifacial spasm and patients undergoing cerebellopontine angle tumor resection., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: Hemifacial spasm (HFS) is a movement disorder characterized by involuntary muscle contractions on one side of the face. It is associated with disturbances in the brain's functional architecture. Despite this, the structural alterations in the brain related to HFS remain poorly understood. In this study, we investigated the cortical morphology changes in patients with HFS compared to healthy controls (HCs)., Methods: We analyzed 3D T1-weighted MRI images from 33 patients with left-sided primary HFS and 33 age- and sex-matched HCs. Measurements of cortical thickness (CTh), sulcal depth, local gyrification index (lGI), and fractal dimension were taken using a computational anatomy toolbox. A general linear model, accounting for age, gender, and total brain volume, was applied for statistical analyses. Significant clusters were then assessed for correlations with clinical parameters., Results: The HFS patients displayed several cortical abnormalities when compared to HCs, including reduced CTh in the contralateral precentral gyrus and left orbitofrontal cortex, decreased sulcal depth in the left orbitofrontal cortex, and increased lGI in the right insula and superior temporal cortex. However, fractal dimension did not differ significantly between the groups. Additionally, in HFS patients, a notable negative correlation was found between the sulcal depth in the left orbitofrontal cortex and the Beck Depression Inventory-II scores., Conclusions: Our findings reveal that HFS is associated with specific surface-based morphological changes in the brain. These alterations contribute to a deeper understanding of the neurophysiological mechanisms involved in HFS and may have implications for future research and treatment strategies., (© 2024. Fondazione Società Italiana di Neurologia.)

Background:  Hemifacial spasm (HFS) is a movement disorder caused by mechanical compression of the facial nerve after it has left the brainstem and is characterized by brief or sustained twitching of the muscles innervated by that nerve. Often we observe spasm in an awakening situation. Actually contractions persist during sleep. To our knowledge, there were no reports on how HFS manifests under disturbance of consciousness. Here, we report a case of primary HFS in which the patient's symptoms persisted in a coma., Case Presentation: A 74-year-old female with right-sided primary HFS for 20 years and had received botulinum toxin injections in our hospital. Unfortunately she was carried to emergency department after traumatic right pneumothorax by accident. During the emergency treatment, she lost consciousness due to simultaneous cardiac arrest and respiratory arrest. She was then admitted to the emergency intensive care unit for further treatment. During her hospitalization, she was in a coma with stable vital signs and persisting symptoms of HFS. Thus, a multidisciplinary consultation was requested to identify whether it was focal cortical seizures involving the right-side facial muscles. Physical examination revealed brief involuntary clonic or tonic contractions accompanied with the 'Babinski-2 sign'. A combination of relevant data, including her past history, clinical presentation and a negative computed tomography scan of the head, led to a diagnosis of right-sided HFS. As the symptoms of HFS are not life-threatening, the use of anticonvulsants is unnecessary., Conclusions: For the layperson, it is crucial to seek a multidisciplinary consultation to obtain a correct diagnosis., (© 2021. The Author(s).)

Objective: Interpreting lateral spread response (LSR) during microvascular decompression (MVD) for hemifacial spasm (HFS) is difficult when LSRs observed in different muscles do not match. We aimed to analyze LSR patterns recorded in both the orbicularis oris (oris) and mentalis muscles and their relationships with clinical outcomes., Methods: The data of 1288 HFS patients who underwent MVD between 2015 and 2018 were retrospectively reviewed. LSR was recorded in the oris and mentalis muscles through centrifugal stimulation of the temporal branch of the facial nerve after preoperative mapping. The disappearance of LSR following surgery, clinical outcomes, and the characteristics of LSR in oris were analyzed., Results: After surgery, LSR remained in 100 (7.7%) and 279 (21.6%) of the mentalis and oris muscles, respectively. The postoperative outcome correlated with LSR disappearance in the mentalis, not with that in the oris., Conclusion: LSR patterns differed in each muscle and may not be correlated with clinical outcomes. LSR in the mentalis and oris muscles should be interpreted differently., Significance: We describe a monitoring protocol characterized by preoperative facial nerve mapping, antidromic stimulation, and recording from multiple muscles. We analyze differences in LSRs in the mentalis and oris muscles and suggest technical points for interpretation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Abstract: Botulinum toxin A is considered an effective treatment for involuntary facial movements. We examined whether treatment efficacy maintained or changed over time with two products, Botox and Dysport, in patients with hemifacial spasm, facial synkinesis and benign essential blepharospasm.We retrospectively investigated 87 consecutive patients (51 women, 36 men) who had undergone treatment for ≥6 years. Long-term effects, as well as side effects of Botox or Dysport local injections were evaluated. The first three treatments were considered the titration period and not taken into account when testing for dose changes.Mean treatment duration was 10 years (range 6-11, SD 1.0), 2441 treatments were administered, 1162 with Botox and 1279 with Dysport, the two brands were interchanged as needed. Good to full improvement was seen in 90% of patients both with both brands. Injection doses and treatment responses were consistent during the study with both drugs. No major side effects were reported, and relatively few minor adverse events were reported, with clear reduction from the titration period (6.1%), to the remainder of the study (3.9%).Botulinum toxin (BTX-A) is a satisfactory long-term treatment without need for dose increase over. Both Botox and Dysport were effective when used interchangeably., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 the Author(s). Published by Wolters Kluwer Health, Inc.)

Introduction: Many researchers have assumed that neurovascular compression of the facial nerve at the site covered by central myelin sheath causes hemifacial spasm. However, some cases do not correspond to this hypothesis. The aim of this study was to clarify the myelin histology in the facial nerve., Materials and Methods: Histological analyses were conducted on 134 facial nerves from 67 cadavers. Three dimensions were measured in these sections: the length from the upper border of the medullopontine sulcus to the boundary between the central and peripheral myelin sheath along the anterior side; the length from the detachment point of the brain stem to the boundary along the posterior side; and the length of the transitional zone (TZ), known as the Obersteiner-Redlich zone., Results: Of the 134 facial nerves, 41 were available for study. The length of the central myelin segment ranged from 4.62 to 12.6 mm (mean 8.06 mm; median 7.98 mm) along the anterior side and from 0.00 to 4.58 mm (mean 1.68 mm; median 1.42 mm) along the posterior side of the facial nerve, and the length of the TZ ranged from 0.00 to 2.76 mm (mean 1.51 mm; median 1.42 mm)., Conclusions: In this study, the length of the central myelin segment in the facial nerve was found to be longer than that previously reported., (© 2020 Wiley Periodicals LLC.)

This study aimed to determine the long-term quality of life (QoL) in hemifacial spasm (HFS) patients after treating with Abo-botulinum toxin A (Abo-BTX). The study assessed the disease-specific QoL (hemifacial spasm questionnaire 30 items; HFS 30), the involuntary movements (abnormal involuntary movement scale; AIMS), general health QoL (Medical Outcomes 36-Item Short Form Health Survey; SF-36), and Depression (the Center of Epidemiologic Studies-Depression questionnaire; CES-D). A total of 74 HFS patients were enrolled from 2012 to 2017. The disease-specific QoL; involuntary movements; and the general health domain of SF 36 were significantly improved after injections of Abo-BTX A in the first few years ( p < 0.04), but significantly decreased at the fifth year of treatment without significant clinical resistance observed ( p < 0.001). Only the general health domain of SF 36 showed persistent improvement over five years ( p = 0.02). In summary, Abo-BTX A can improved quality of life in the first few years; however only the general health domain of SF-36 showed significant improvement over five years ( p = 0.02). No clinical resistance was observed.

Background: An indentation, designating a furrowed hole on the facial nerve, has been used in many studies for locating pathophysiology and assessing relevant clinical outcomes after microvascular decompression for hemifacial spasm (HFS). In this study, we sought to elucidate the contributing factors forming indentation on the facial nerve and the consequent effect of having indentation on the clinical course., Methods: We divided the patients into 2 groups: group A, the patients who had no indentation on the root exit zone of the facial nerve; and group B, the patients who had an indentation. Demographic data, intraoperative findings, and clinical outcomes were analyzed from retrospective review of the medical records., Results: Of the 132 patients, 47.0% had an indentation on the facial nerve. Our statistical analyses showed that the preoperative symptom period, compression location, and compression pattern were associated with the occurrence of the indentation. Also, we showed that HFS reappearance developed more frequently in patients in group B, who needed more time for the resolution of HFS. The final clinical outcome was less influenced by the existence of the indentation, although it was slightly poorer for group B than for group A., Conclusions: The indentation on the facial nerve was associated with longer duration of symptoms, the presence of compression in the proximal segment of the root exit zone, and loop-type pattern of compression. More patients with indentation experienced the HFS reappearance phenomenon, which lasted longer than in those who had no indentation., (Copyright © 2020 Elsevier Inc. All rights reserved.)

To explore the causes of persistent abnormal muscle response (AMR) after microvascular decompression (MVD) for hemifacial spasm (HFS) and the clinical outcomes of these patients. MVDs performed in Nanjing Drum Tower Hospital in 2017 were retrospectively studied, and 326 patients with HFS were classified into two groups based on whether AMR disappeared or persisted following MVD. The clinical features, treatment efficacy and postoperative complications were compared between the two groups. 305 patients with disappeared AMR after decompression were classified as Group A. In Group B, the 21 patients exhibited persistent AMR after successful MVD. The preoperative duration of symptoms in Group B was significantly longer than that in Group A (P < 0.001), and no significant difference was identified between the two groups in terms of gender, side, age and offending vessels (P > 0.05). The immediate postoperative cure rate of Group A (88.9%)was significantly higher than that in Group B (28.6%, P < 0.001), furthermore, the two groups were not different in the long-term outcome and the incidence of surgical complications (P > 0.05). The long preoperative duration of HFS patients may account for persistent AMR after successful decompression, and it is more likely for these patients to get delayed cured, the long-term outcomes showed no difference compared to those in patients with disappeared AMR after MVD.

Background: Microvascular decompression (MVD) is the surgical treatment of choice for hemifacial spasm (HFS). During MVD, monitoring of the abnormal lateral spread response (LSR), an evoked response to facial nerve stimulation, has been traditionally used to monitor adequacy of cranial nerve (CN) VII decompression., Objective: To assess the utility of LSR monitoring in predicting spasm-free status after MVD postoperatively., Methods: We searched PubMed, Web of Science, and Embase for relevant publications. We included studies reporting on intraoperative LSR monitoring during MVD for HFS and spasm-free status following the procedure. Sensitivity of LSR, specificity, diagnostic odds ratio, and positive predictive value were calculated., Results: From 148 studies, 26 studies with 7479 patients were ultimately included in this meta-analysis. The final intraoperative LSR status predicted the clinical outcome of MVD with the following specificities and sensitivities: 89% (0.83- 0.93) and 40% (0.30- 0.51) at discharge, 90% (0.84-0.94) and 41% (0.29-0.53) at 3 mo, 89% (0.83-0.93) and 40% (0.30-0.51) at 1 yr. When LSR persisted after MVD, the probability (95% CI) for HFS persistence was 47.8% (0.33-0.63) at discharge, 40.8% (0.23-0.61) at 3 mo, and 24.4% (0.13-0.41) at 1 yr. However, when LSR resolved, the probability for HFS persistence was 7.3% at discharge, 4.2% at 3 mo, and 4.0% at 1 yr., Conclusion: Intraoperative LSR monitoring has high specificity but modest sensitivity in predicting the spasm-free status following MVD. Persistence of LSR carries high risk for immediate and long-term facial spasm persistence. Therefore, adequacy of decompression should be thoroughly investigated before closing in cases where intraoperative LSR persists., (Copyright © 2020 by the Congress of Neurological Surgeons.)

Objective: To investigate the prognostic and predictive value of intraoperative blink reflex (BR) monitoring during microvascular decompression (MVD) for hemifacial spasm (HFS)., Methods: We retrospectively reviewed 41 patients with HFS undergoing MVD with intraoperative BR and lateral spread response (LSR) monitoring. Facial spasm was evaluated for six months postoperatively., Results: The BR resolved in 38 patients and persisted in three after MVD. For patients who exhibited BR resolution, 1-day, 1-month, and 6-month follow-ups revealed that 35 (92.1%), 35 (92.1%), and 38 (100%) patients had spasm resolution, respectively. However, of the three patients with persistent BR, one (33.3%), one (33.3%), and zero (0%) patients exhibited spasm resolution at the three corresponding follow-ups. We found a statistically significant difference in spasm resolution between the persistent and resolved BR groups at six months postoperatively. A comparison between intraoperative BR and LSR monitoring revealed that BR was a better predictor of clinical outcomes., Conclusions: Intraoperative BR monitoring is a potentially useful tool to help facilitate an adequate decompression and is a reliable prognostic predictor of surgical outcome., Significance: This study is the first to document the relationship between intraoperative BR monitoring and surgical outcome in patients with HFS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Background: Although the nonaffected side appears to be clinically normal in hemifacial spasm (HFS), it is not known whether this side can be considered normal regarding histopathological findings. The purpose of this study was to objectively evaluate and compare orbicularis oculi samples of patients with HFS (not previously treated with botulinum toxin) and control patients undergoing cosmetic upper eyelid blepharoplasty., Methods: Orbicularis oculi samples from 22 eyelids were evaluated. There were 7 samples from the affected and 7 samples from the nonaffected sides of patients with HFS who had not been previously treated with botulinum toxin, and 8 samples from normal control patients. Muscle samples were prepared using hematoxylin and eosin staining, and a digital image analysis software was used for objective analyses., Results: When compared with normal controls, endomysial and perimysial connective tissue areas were significantly increased (P = 0.015) on the affected side in HFS, suggesting that this disorder is associated with chronic alterations that lead to muscle degeneration. Cell density was significantly reduced on the affected (P = 0.028) and also on the nonaffected sides in HFS (P = 0.003) compared with normal controls. This was observed, although, clinically, there were no signs or symptoms of increased muscular contraction on the nonaffected sides in any of the patients with HFS studied., Conclusions: Significant morphological differences in the orbicularis oculi muscle in patients with HFS were observed on both the affected and nonaffected sides. Our findings suggest a potential role for muscle homeostasis disturbances on both sides for patients with HFS. Affected sides in patients with HFS did, however, demonstrate muscle degeneration that was not present on the nonaffected sides.

Objective: To perform a comprehensive meta-analysis to systematically assess the value of abnormal muscle response (AMR) in predicting the surgical outcome of patients with hemifacial spasm., Methods: The electronic database PubMed, Embase, Web of Science, and ScienceDirect were searched, and relevant articles were identified up to September 30, 2019. These data were extracted for pooled analysis, heterogeneity testing, sensitivity analysis, publication bias analysis, and Fagan plot analysis., Results: The disappearance of AMR during microvascular decompression was associated with a favorable short-term surgical outcome (pooled relative risk [RR], 1.42; 95% confidence interval [CI], 1.24-1.62; pooled RR adjusted for publication bias, 1.30; 95% CI, 1.08-1.57). The corresponding pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 0.91 (95% CI, 0.88-0.94), 0.34 (95% CI, 0.27-0.42), 1.4 (95% CI, 1.2-1.6), 0.26 (95% CI, 0.17-0.38), and 5 (95% CI, 3-9), respectively. The disappearance of AMR was almost ineffective in predicting the long-term surgical outcome (pooled RR, 1.09; 95% CI, 1.02-1.17; pooled RR adjusted for publication bias, 1.001; 95% CI, 0.92-1.09). The corresponding pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 0.90 (95% CI, 0.85-0.93), 0.28 (95% CI, 0.20-0.37), 1.2 (95% CI, 1.1-1.4), 0.38 (95% CI, 0.22-0.63), and 3 (95% CI, 2-6), respectively., Conclusions: The disappearance of AMR during microvascular decompression demonstrates limited prognostic value for a favorable short-term outcome, and does not appear effective in predicting the long-term outcome of patients with hemifacial spasm., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: In spite of the well-known importance of thalamus in hemifacial spasm (HFS), the thalamic resting-state networks in HFS is still rarely mentioned. This study aimed to investigate resting-state functional connectivity (FC) of the thalamus in HFS patients and examine its association with clinical measures., Methods: 25 HFS patients and 28 matched healthy controls underwent functional MRI at rest. Using the left and right thalamus as seed regions respectively, we compared the thalamic resting-state networks between patient and control groups using two independent sample t -test., Results: Compared with controls, HFS patients exhibited strengthened bilateral thalamus-seeded FC with the parietal cortex. Enhanced FC between right thalamus and left somatosensory association cortex was linked to worse motor disturbance, and the increased right thalamus-right supramarginal gyrus connection were correlated with improvement of affective symptoms., Conclusion: Our findings indicate that the right thalamus-left somatosensory association cortex hyperconnectivity may represent the underlying neuroplasticity related to sensorimotor dysfunction. In addition, the upregulated FC between the right thalamus and right supramarginal gyrus in HFS, is part of the thalamo-default mode network pathway involved in emotional adaptation., Advances in Knowledge: This study provides new insights on the integrative role of thalamo-parietal connectivity, which participates in differential neural circuitry as a mechanism underlying motor and emotional functions in HFS patients.

Objective: We sought to define the significance of wave I loss of brainstem auditory evoked potentials (BAEPs) during microvascular decompression (MVD) surgery for hemifacial spasm., Methods: Out of 670 patients, 36 showed wave V loss during MVD surgery. These patients were classified into the following two groups based on wave I loss: Total wave loss, including wave I loss, and wave V loss with persistent wave I. We analyzed the differences in postoperative complications between the groups. We also investigated when wave I loss occurred during MVD surgery., Results: Of the 36 patients, 24 (66.7%) exhibited wave I persistence and 12 (33.3%) exhibited total wave loss. The patients who showed total wave loss were significantly more likely to exhibit postoperative hearing loss (p = 0.009). In addition, these patients exhibited a significantly higher frequency of postoperative complications such as dizziness and tinnitus (p = 0.002 and p = 0.031, respectively). Total wave loss occurred more frequently after the decompressive procedure of MVD surgery., Conclusions: Total wave loss, including wave I loss, was more closely associated with severe postoperative complications. Total wave loss occurred more frequently after the decompressive procedure of MVD surgery., Significance: These findings suggest the significance of wave I loss of BAEPs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

To assess spontaneous blinking and anomalous eyelid movements in patients with hemifacial spasm with an emphasis on interocular differences. Spontaneous eyelid movements were registered bilaterally for 3 min using a high-speed video camera in 28 patients with hemifacial spasm (HFS) who had not been treated with botulinum toxin injections for at least 5 months. The degree of blink conjugacy, maximum velocity, and amplitude of the closing phase of the blinks were determined for the affected and non-affected sides. Out of the 28 subjects, 23 (82%) presented with abnormal nonconjugate spasms that were similar to blinks, and in 17 (61%), high-frequency eyelid twitches were detected between blinks on the affected eye. The rate of nonconjugate blink-like spasms ranged from 0.3 to 24.7 movements/min. With regard for conjugate blinks, there was no significant interocular difference in amplitudes or eyelid closure velocities. The amplitude and velocity were significantly lower for nonconjugate movements than for spontaneous blinks. HFS is a unique condition in which complex patterns of eyelid movements, including both conjugate and nonconjugate movements, are present. Conjugate movements correspond to spontaneous blinking, and the same metrics were observed in affected and non-affected eyes. Nonconjugate movements correspond to anomalous nonconjugate blink-like spasms and high-frequency eyelid twitches in the affected eye, both of which were characterized by lower amplitudes and velocities than were observed in conjugate movements.

Objective: The progression rate for clinical manifestations in hemifacial spasm (HFS) varies; however, little is known about the factors contributing to this. The purpose of this study was to identify independent factors affecting the rate of symptom progression and to evaluate clinical outcomes according to progression rates., Methods: The study enrolled 1335 patients who underwent microvascular decompression for HFS between July 2004 and January 2015. We assessed detailed history, clinical manifestations, and outcomes. Based on the duration and severity of symptoms, patients were classified into rapidly progressive and slowly progressive groups. We identified predisposing factors affecting the differences between the 2 groups and evaluated the clinical outcome in each group., Results: Of 1335 patients with HFS, 825 (61.8%) were classified as rapidly progressive, and 510 (38.2%) were classified as slowly progressive. In univariable and multivariable analyses, younger age at surgery, older age at symptom onset, and absence of intraoperative facial nerve indentation were significant predisposing factors for rapid progression. The rapidly progressive group had worse outcomes than the slowly progressive group following microvascular decompression., Conclusions: In this study, patients with rapidly progressive HFS had worse clinical outcomes. Therefore, patients with rapidly progressive symptoms should be warned in advance that the prognosis may be worse after microvascular decompression. This study is also useful to understand the differences in symptom progression rates in HFS in order to inform patients about symptom progression., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Intraoperative abnormal muscle response (AMR) is widely used as an indicator during microvascular decompression surgery for hemifacial spasm. Usually only 1 muscle is recorded, and not all patients show a response, leaving the surgery somewhat blinded. We propose an improved method to record from multiple muscles innervated by multiple branches of the facial nerve to increase the positive AMR detection rate., Methods: Retrospective analysis was performed of 1604 patients with hemifacial spasm undergoing microvascular decompression at a single center. All patients were monitored for AMR by stimulating the zygomatic branch of the facial nerve. Only mentalis was recorded in 158 cases (single-branch AMR). Orbicularis oris, frontalis, and mentalis were simultaneously monitored in 148 cases (3-branch AMR), and platysma was further added in the remaining 1298 cases (4-branch AMR). Positive AMR detection rates were compared across the groups., Results: Total positive AMR detection rates significantly increased as more muscles were included in monitoring and were 74.1% for single-branch AMR, 86.5% for 3-branch AMR, and 98.4% for 4-branch AMR. Detection rates from single muscles were not significantly different across the groups. For all available cases, rates were 73.5% from mentalis, 47.2% from frontalis, 64.1% from orbicularis oris, and 40.8% from platysma., Conclusions: This new multibranch AMR monitoring method can effectively increase the positive detection rate to as high as 98.4%. It is expected to better assist surgery., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: Microvascular decompression (MVD) has been widely accepted for treating hemifacial spasm (HFS) and glossopharyngeal neuralgia (GN); an effective surgical treatment of coexistent HFS and GN still remains to be determined, however. In this paper we discuss the operative strategy of MVD for patients with coexistent HFS and GN., Methods: This was a retrospective study. All cases of HFS with or without GN at China-Japan Friendship Hospital from January 2014 to June 2016 have been included. All patients underwent MVD and have been followed up for an average of 1.5 years., Results: A total of 5375 cases of HFS were included, wherein 8 cases coexist with GN. Eight patients had same offending vessel(s) compressing the root entry zone of glossopharyngeal nerve and facial nerve. Posterior inferior cerebellar artery was identified as at least 1 of the offending arteries in all 8 patients. After MVD, spasm ceased in all 8 cases, with 7 cases ceasing immediately and 1 within 2 months. Pain disappeared also in all cases, with 7 cases immediately and 1 case after 4 days. No recurrence or complication was observed during the follow-ups., Conclusions: HFS combined with ipsilateral GN was rare. MVD could be performed to effectively relieve nerve root compression and associated symptoms for coexistent HFS and GN. Sufficient exposure of root entry zones of both nerves and fully decompression of offending blood vessels and exploratory sequences of different nerve roots are critical points for improving operative effect and reducing complications., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: This study aims to quantitatively compare the Jankovic assessment (JA) with electromyography (EMG)-based measures for assessing changes in facial movements in patients with facial dystonia., Materials and Methods: Thirteen patients (five males and eight females) affected with different forms of facial dystonia (hemifacial spasm and synkinesis) participated in this study. All patients were treated with Botulinum Toxin (BTX) and evaluated with the JA scale and EMG-based measures, including motor unit potentials (MUP) latency and presence of polyphasic potentials before and after BTX injection. Correlation between the JA scores and the EMG-based measures was calculated. Statistical analysis was performed with the Pearson test., Results: Correlation between the JA scores and the EMG-based measures was found to be statistically significant, both before and after treatment with BTX., Conclusion and Relevance: JA scores significantly correlated with more objective EMG-based measures, suggesting that the JA scale can be used to assess facial movement changes, for example elicited by a treatment such as BTX injection. Thus, in facial dystonia patients, the JA scale may be used for evaluating treatment outcomes as a valid and low-cost alternative to EMG., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Introduction: Charcot-Marie-Tooth (CMT) phenotypes can be distinguished by electrophysiology and genetic analysis but few can be identified by their clinical characteristics. Distinctive phenotypes are useful in identifying affected individuals and providing additional clues about the mechanism of the neuropathy. Cranial neuropathies are uncommon features of CMT, and few reports of familial hemifacial spasm (HFS) and trigeminal neuralgia (TN) have been published., Methods: Sixty-three members of a large CMT 1B kindred were assessed for signs of peripheral neuropathy and cranial neuropathies then tested for the G163R mutation in the myelin protein zero (MPZ) gene., Results: Of 27 individuals with the G163R mutation in MPZ, 10 had HFS or TN. Co-existing HFS and TN were found in 3 of these and 4 had bilateral HFS or TN., Conclusions: This kindred exhibits a distinct CMT phenotype characterized by the development of HFS or TN decades after clinical signs of hereditary neuropathy are manifest. Muscle Nerve, 2019., (© 2019 Wiley Periodicals, Inc.)

Background: Polysomnography (PSG) studies in patients with facial dyskinesias are few. With regard to hemifacial spasm (HFS), one study reported the continuity of spasms during sleep which was not confirmed elsewhere using a PSG. Therefore, we sought to investigate abnormal facial movements during sleep in patients with HFS., Methods: All patients have undergone PSG assessments. Facial spasms were recorded using an electromyography (EMG) and quantified according to the duration of the hyperkinetic episodes in each epoch of 60 s. Scores were compared between wakefulness and sleep as well as within the sleep stages. Number of arousals and their association with the EMG activity is also evaluated., Results: Twelve patients with a mean age of 58 (35-76) years and disease duration of 7.8 (2-20) years were included in the study. In seven of them all sleep stages were detected. Facial spasms continued in sleep in all patients with a significant decrease compared to wakefulness (p < 0.001). No significant difference between non-REM and REM stages are found with regard to EMG activity (p = 0.35). On average, sleep was interrupted 5.9 (±2.8) times mostly in non-REM-II and least in REM sleep., Conclusion: This study confirms the continuity of hyperkinetic movements of HFS during sleep despite a significant decrease compared to wakefulness causing increased arousals. These findings highlight the importance of assessing the sleep quality in patients with HFS., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: In the present study, we investigated whether blink synkinesis monitoring during microvascular decompression (MVD) is effective for predicting long-term outcomes in patients with hemifacial spasm (HFS)., Methods: This retrospective study included 69 patients who had undergone MVD for HFS at a tertiary hospital. All patients underwent intraoperative monitoring of blink synkinesis, lateral spread responses (LSRs), and facial nerve motor-evoked potentials (FNMEPs). Baseline signals were compared to those obtained following decompression with Teflon, and postoperative outcomes were recorded., Results: A total of 65 patients were observed with complete relief of symptoms after 1 year after MVD, while 61 patients were observed with initial disappearance of blink synkinesis, 57 patients were observed with initial elimination of the LSR, and 45 patients with initial decreases in FNMEP amplitude (>50%). The highest sensitivity and accuracy values were observed for blink synkinesis. Chi-square tests comparing the sensitivity of the three methods revealed that FNMEP monitoring was associated with significantly lower sensitivity values than the remaining methods. Combined use of blink synkinesis and LSRs did not significantly increase sensitivity (61/65 vs 62/65) or accuracy (62/69 vs 63/69)., Conclusion: Our results demonstrate that blink synkinesis monitoring is safe during MVD for HFS. Furthermore, blink synkinesis was associated with the highest sensitivity and predictive values among the three methods evaluated. These findings suggest that blink synkinesis can be regarded as the first choice for intraoperative monitoring during MVD. Concurrent use of blink synkinesis and LSR monitoring may maximize the ability to predict patient prognosis and determine the extent of decompression.

The aim of the study was to evaluate the effects of writing, reading, and speaking on orbiculari oculi (OO) muscle spasms and on the blink rate in patients with blepharospasm (BSP). Patients with hemifacial spasm (HFS) and healthy subjects (HS) acted as control subjects. Thirty patients with BSP, 20 patients with primary HFS and 20 age-matched healthy subjects were videotaped according to a standardized procedure: at rest with eyes open; while writing a standard sentence on paper; while writing a standard sentence on a blackboard keeping the head straight; during a conversation based on a simple topic (speaking task); and while reading a standard text aloud. Two independent movement disorders specialists reviewed the videotapes and measured the number of OO spasms and blinks in each segment. Writing and reading reduced the number of OO spasms in BSP patients, whereas speaking did not. On the other hand, writing, reading, and speaking did not modify spasms in HFS patients. These tasks modulated the blink rate in all the three groups of subjects (BSP, HFS, and HS). Our hypothesis is that the modulation of OO spasm in BSP during writing and reading depends on influences coming from occipital areas onto the brainstem circuits. Whether cognitive training with reading and writing may be used to improve OO muscle spasms is an issue that warrants further investigation.

This study is to identify the risk factors for postoperative delirium (PODE) in patients undergoing microvascular decompression (MVD) for the treatment of primary cranial nerve disorders. We retrospectively reviewed the data of 912 patients (354 men, 558 women) with primary cranial nerve disorders (trigeminal neuralgia, 602 patients; hemifacial spasm, 296 patients; glossopharyngeal neuralgia, 14 patients) who underwent MVD in the Neurosurgery Department of Lanzhou University Second Hospital between July 2007 and June 2018. Potential risk factors for PODE were identified using univariate and multivariate stepwise logistic regression analysis.Of the 912 patients, 221 (24.2%) patients developed PODE. Patients with PODE were significantly older and significantly more likely to be male than patients without PODE. A history of hypertension, preoperative carbamazepine therapy, and postoperative sleep disturbance and tension pneumocephalus were independently associated with PODE. Variables such as body-mass index, smoking and drinking habits, cardiac disease, diabetes mellitus, cerebrovascular disease, mean operative time, affected vessel, mean blood loss, postoperative intensive care unit stay, postoperative fever (>38°C), and routine laboratory results were not associated with PODE in our patients.PODE is a common complication after MVD, and is associated with multiple risk factors, including old age, male sex, hypertension, preoperative carbamazepine use, postoperative sleep disturbance, and tension pneumocephalus., Competing Interests: The authors have declared that no competing interests exist.

Purpose: The purpose of this study was to assess the long-term outcome of onabotulinum used to treat facial dystonia and compare a flexible and fixed treatment regimen., Methods: This was a retrospective comparative study looking at benign essential blepharospasm (BEB), hemifacial spasm (HFS) and aberrant facial nerve regeneration synkinesis (AFR) treatment with onabotulinum toxin A (Botox®) over a minimum of 10 years. Fifty-one patients were recruited into the study, with each dystonia subgroup having 17 patients. Blepharospasm disability score (BDS), subjective improvement score (SIS), duration of maximal effect (DME) and complications were recorded at each visit., Results: The mean age was 63 years and gender predominately female. Thirty-seven patients underwent flexible treatment intervals compared to 14 fixed treatment intervals, averaging 3.4 and 4 per annum, respectively. Mean BDS significantly improved from 6 to 3 at last review across all 3 groups, with the highest effect on BEB. BDS improvement was greater in flexible intervals. SIS remained similar for all three conditions during follow-up, but in those undergoing flexible intervals, SIS increased by a small margin compared to fixed interval. Mean DME was 10.5 weeks across all dystonias, but increased progressively only in the flexible interval group. Complications included ptosis (30%), dry eye (14%) and lagophthalmos (8%)., Conclusion: Flexible onabotulinum provided better long-term relief on BDS for facial dystonia than a fixed regimen. Flexible interval treatment may also provide better patient satisfaction and longer DME compared to fixed treatment. Both have similar complication rates. With flexible treatment however, fewer injections were required over 10 years, leading to cost saving.

Objective: The compression of the offending vessel on the facial nerve at root exit zone is considered as the leading cause of hemifacial spasm (HFS). However, the correlation between the severity of spasm and the pressure of neurovascular compression (NVC) has not yet been investigated. The aim of this study was to investigate the clinical correlation between the severity of HFS and the pressure of NVC., Methods: A prospective study was performed, which included 52 of 151 patients who underwent microvascular decompression. We classified the preoperative spasm severity according to the Cohen scores. Codman intracranial pressure monitoring system was used to measure the NVC pressure at the root exit zone during microvascular decompression. All patients were followed up for 12-24 months., Results: Herein, the intraoperative pressure readings of NVC were in the range of 21-63 mmHg. The means of the pressure of NVC that corresponded to the Cohen scores (1-4) were 23.00 ± 1.83, 34.91 ± 12.42, 46.50 ± 9.40, and 55.40 ± 3.03 mmHg, respectively. The Spearman's rank correlation established a strong positive correlation between the pressure and the Cohen scores (r = 0.689, P < 0.0001). The simple linear analysis indicated that sex (P = 0.132), duration (P = 0.304), and delayed relief (P = 0.158) were not significantly associated with the pressure. However, a substantial correlation was determined between the pressure values and the time until the complete recovery (r = 0.949, P < 0.0001) of the delayed healing population., Conclusions: The severity of HFS exhibited a strong positive correlation with the intraoperative offending vessel's pressure values. Thus, the neurovascular pressure is a significant factor in the pathogenesis of HFS., (Copyright © 2018. Published by Elsevier Inc.)

Objective: Microvascular decompression (MVD) is widely considered the treatment of choice for hemifacial spasm (HFS), but not all patients immediately benefit from it. Numerous electrophysiological tests have been employed to monitor the integrity of the facial nerve prior to, during, and after MVD treatment. The authors sought to verify if facial motor evoked potential (FMEP) with paired transcranial magnetic stimulation (pTMS) can be utilized as a tool to predict prognosis following MVD for HFS., Methods: FMEP using pTMS was performed preoperatively and postoperatively for 527 HFS patients who underwent an MVD treatment. Various interstimuli intervals (ISIs), which included 2, 10, 20, 25, 30, 75, and 100 msec, were applied for each paired stimulation and pTMS(%) was obtained. A graph of pTMS(%) versus each ISI was drawn for every patient and its pattern was analyzed in accordance with patients' clinical outcomes., Results: With ISIs of 75 and 100 msec, pTMS(%) was physiologically further inhibited, whereas it was relatively facilitated under ISIs of 20, 25, and 30 msec; loss of this specific pattern, that is, further inhibition-relative facilitation, indicated impaired integrity of the facial nerve. Those patients who immediately benefited from an MVD and experienced no relapse tended to show proper restoration of this further inhibition-relative facilitation pattern (p = 0.01). Greater resemblance between the physiological pattern of pTMS(%) and postoperative pTMS(%) was correlated to better outcome (p = 0.019)., Conclusions: A simple linear graph of pTMS(%) versus each ISI may be a helpful tool to predict prognosis for HFS following an MVD.

Objective: Hemifacial spasm (HFS) is caused by arterial conflict at the root exit zone of the facial nerve. As the offending artery is pulsatile in nature, this study investigated the association of heart rate fluctuation with HFS., Methods: Twenty-four preoperative patients underwent simultaneous recordings of facial electromyogram and electrocardiogram overnight. Series of R-wave to R-wave intervals (RRIs) in the electrocardiogram were analyzed across subjects in relation to HFS. The degree of heart rate fluctuation was quantified by analyzing the heart rate variability (HRV). The sleep stage was evaluated during the period of HFS., Results: A 0.1 Hz fluctuation in RRIs by 5% compared to the baseline preceded a few seconds the onset of the HFS, indicating that a significant increase in the heart rate coincided with HFS. HRV analysis demonstrated that fluctuations in the heart rate were significantly enhanced during HFS. Wake or light sleep stages were more often accompanied by HFS, suggesting an association with autonomic activities., Conclusion: Our findings suggest that the etiology of HFS is more than just a mechanical compression of the facial nerve and may involve changes in pulsatile frequency in offending arteries., Significance: We propose the etiology of HFS from a unique standpoint., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Objectives: To determine whether serum levels of anti-acetylcholine receptor antibody (anti-AChR-Abs) are related to clinical parameters of blepharospasm (BSP)., Methods: Eighty-three adults with BSP, 60 outpatients with hemifacial spasm (HFS) and 58 controls were recruited. Personal history, demographic factors, response to botulinum toxin type A (BoNT-A) and other neurological conditions were recorded. Anti-AChR-Abs levels were quantified using an enzyme-linked immunosorbent assay., Results: The anti-AChR Abs levels were 0.237 ± 0.022 optical density units in the BSP group, which was significantly different from the HFS group (0.160 ± 0.064) and control group (0.126 ± 0.038). The anti-AChR Abs level was correlated with age and the duration of response to the BoNT-A injection., Conclusion: Patients with BSP had an elevated anti-AChR Abs titer, which suggests that dysimmunity plays a role in the onset of BSP. An increased anti-AChR Abs titer may be a predictor for poor response to BoNT-A in BSP.

Objective: To examine a new abnormal muscle response (AMR) monitoring method during microvascular decompression (MVD) for hemifacial spasm., Methods: 486 patients with hemifacial spasm were monitored for an AMR during MVD with a new method involving preoperative mapping and intraoperative centrifugal stimulation of the facial nerve. For the last 62 patients, we performed the AMR monitoring using both, the new and conventional methods simultaneously., Results: Preoperative facial nerve mapping showed that the maximal AMR was detected most frequently (66.9%) at the "F" location (the direction towards the frontalis muscle). An intraoperative AMR was observed in 86.2% of the patients, which disappeared after MVD in 96.4% of the patients. A comparison of the new and conventional methods respectively showed that AMR disappearance after MVD was observed in 98.2% and 61.8% of the patients, no AMR in 0% and 9.1%, and persistent AMR after MVD in 1.8% and 29.1%., Conclusions: The new AMR monitoring method demonstrated greater AMR monitoring efficacy and supports the finding that disappearance of an AMR is a good indicator of effective decompression during MVD surgery., Significance: Preoperative mapping and intraoperative centrifugal stimulation of the facial nerve during MVD surgery in HFS patients showed greater efficacy of AMR monitoring., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Objective: The aim of this study was to define the critical warning sign of real-time brainstem auditory evoked potential (BAEP) for predicting hearing loss (HL) after microvascular decompression (MVD) for hemifacial spasm (HFS)., Methods: Nine hundred and thirty-two patients with HFS who underwent MVD with intraoperative monitoring (IOM) of BAEP were analyzed. We used a 43.9 Hz/s stimulation rate and 400 averaging trials to obtain BAEP. To evaluate HL, pure-tone audiometry and speech discrimination scoring were performed before and one week after surgery. We analyzed the incidence for postoperative HL according to BAEP changes and calculated the diagnostic accuracy of significant warning criteria., Results: Only 11 (1.2%) patients experienced postoperative HL. The group showing permanent loss of wave V showed the largest percentage of postoperative HL (p < 0.001). No patient who experienced only latency prolongation (≥1 ms) had postoperative HL. Loss of wave V and latency prolongation (≥1 ms) with amplitude decrement (≥50%) were highly associated with postoperative HL., Conclusions: Loss of wave V and latency prolongation of 1 ms with amplitude decrement ≥50% were the critical warning signs of BAEP for predicting postoperative HL., Significance: These findings elucidate the critical warning sign of real-time BAEP., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

The diagnosis of primary hemifacial spasm (pHFS), due to a benign compression of the facial motor nerve by a vessel, within or close to its root exit zone, is often made with delay. Misdiagnosis includes psychogenic spasm, tics, facial myokymia or blepharospasm, but in fact post-facial palsy synkinesis (post-paralytic HFS) is the closest clinical condition, because it is limited to the territory of the facial nerve of a single hemiface. The differential diagnosis between these two entities, whose pathophysiological mechanisms are very different, can be made by electroneuromyographic (ENMG) examination. In addition, magnetic resonance imaging (MRI) is essential to show the offending vessel at the origin of pHFS and the absence of other causes of nerve compression. However, the diagnosis cannot be made on MRI basis alone, since a neurovascular conflict can be present in clinically asymptomatic subjects. This article reviews the clinical, MRI, and ENMG features in favour of a pHFS diagnosis as well as the various differential diagnoses of this involuntary facial movement disorder., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Objective: Although hearing impairment after microvasuclar decompression (MVD) for hemifacial spasm (HFS) is not common, its occurrence could detrimentally affect the patient's surgical outcome. The object of this study is to address the optimal approaches for reducing postoperative hearing problems after MVD for HFS., Methods: We retrospectively analyzed the medical records of patients with HFS who underwent MVD with the same surgeon at our institute from March 2003 to October 2016, and reviewed the pertinent literature. Patients who were followed up for more than 6 months were selected, resulting in the analysis of 1434 total patients. Postoperative hearing complications were evaluated audiometrically and subjectively (patient-reported symptoms). Clinical factors such as the intraoperative findings were reviewed to identify their correlation with auditory function., Results: Symptoms in 1333/1434 patients (93.0%) resolved more than 90% from their preoperative state. Among them, 16 patients (1.1%) complained of hearing impairment after surgery. Most impairment was transient, although 6/1333 patients (0.4%) required additional interventions for persistent hearing deficits (one surgical intervention and five hearing aids). A >50% decrease in the amplitude of brainstem auditory evoked potentials during the operation was significantly associated with postoperative hearing deficits., Conclusions: Few auditory complications, mostly transient, result from MVD. Although MVD is a commonplace surgical technique, to reduce complications it is important to emphasize the need for clean exposure of the lower cranial nerves (except for cranial nerve VIII) to obtain enough working space, sharp arachnoid dissection, minimal cerebellar retraction, and proper responses to changes identified during intraoperative monitoring., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Microvascular decompression (MVD) is the most effective treatment for hemifacial spasm (HFS). During MVD surgery, abnormal muscle response (AMR) is widely used. Z-L response (ZLR) is a new monitoring method for HFS. We compared the effectiveness of AMR plus ZLR and simple AMR., Methods: In a retrospective study of 1868 cases of HFS treated using intraoperative monitoring between January 2013 and December 2015, 896 patients underwent simple AMR monitoring and 972 underwent combined intraoperative monitoring of AMR and ZLR., Results: AMR waveforms were observed in 837 (93.42%) patients in the AMR group and in 898 (92.39%) patients in the AMR plus ZLR group (P > 0.05). During MVD, AMR waveforms disappeared in 772 patients in the AMR group and 854 patients in the AMR plus ZLR group (P < 0.05). The efficacy rate of MVD in the AMR plus ZLR group was higher compared with the AMR group when AMR was not detected or disappeared during the operation (P < 0.05). When AMR persisted during the operation, there was no significant difference between the 2 groups in efficacy of the operation (P > 0.05)., Conclusions: Regardless of whether the compression vessels of the facial nerve are simple or complicated, combined intraoperative monitoring of AMR plus ZLR monitoring provides more valuable neurosurgical guidance than simple AMR during MVD for HFS., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Microvascular decompression (MVD) is the most useful treatment for hemifacial spasm (HFS). In patients of vertebral artery (VA) compression of the facial nerve, MVD is often difficult. Many of the VA are obviously atherosclerotic. In this study, the authors retrospectively compared the effect of MVD for HFS associated with the atherosclerosis of vertebral artery (aVA) with that of MVD for HFS with normal vertebral artery (nVA)., Methods: A retrospective study of HFS treated by MVD was conducted between January 2014 and October 2015. There were 186 patients with VA-associated HFS who underwent their first MVD at the authors' institution. Among them, 52 patients of HFS were associated with aVA and 134 patients were associated with nVA., Results: At 1 day, 7 days, 1 month, 3 months, and 1 year after MVD surgery, in aVA group, the effective rate of MVD was 80.77%, 80.77%, 82.00%, 79.59%, and 82.61%, the incidence rate of complication was 15.83%, 13.46%, 14.00%, 12.24%, and 10.87%; in nVA group, the effective rate of operation was 94.03%, 94.78%, 95.42%, 94.53%, and 95.12% (P < 0.05), the incidence rate of complication was 4.48%, 4.48%, 3.82%, 3.13%, and 1.63% (P < 0.05)., Conclusion: When the HFS was associated with the aVA, the effective rate of MVD was lower and the incidence of complication was higher than those associated with nVA. In MVD of HFS associated with aVA, the full decompression of the facial nerve and the minimal traction of surrounding tissue in the operation are the key to the success of MVD.

Background: Ectopic cerebellar tissue located distantly from the normal cerebellum is very rare, and its pathophysiology remains to be elucidated., Case Presentation: We report an extremely rare case of intraosseous ectopic cerebellum detected incidentally at suboccipital craniotomy in a 46-year-old Japanese woman with hemifacial spasm. She had a small bone defect in the occipital bone, which contained a tiny area of soft tissue surrounded by cerebrospinal fluid connecting to the normal subarachnoid space through a dural opening. Histopathology demonstrated cerebellar cortex tissue consisting of molecular and granular cell layers., Conclusions: This is the first report of glioneuronal ectopia within the skull bone separated from normal brain tissue, and it is important to distinguish this entity from other osteolytic lesions.

'Painful tic convulsif' (PTC) describes the coexistence of hemifacial spasm and trigeminal neuralgia. In this report, we describe a unique presentation of bilateral PTC in a man with bilateral hemifacial spasm and trigeminal neuralgia secondary to neurovascular conflict of all four cranial nerves. Following failed medical and radiofrequency therapy, microvascular decompression of three of the four involved nerves was performed, where the offending vessels were mobilised and Teflon used to prevent conflict recurrence. He continues to respond to Botox for right hemifacial spasm. Since surgery, he remains pain free bilaterally and spasm free on the left., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

The objective of this study is to explore the cause of early abnormal muscle response (AMR) disappearance during microvascular decompression for hemifacial spasm and the clinical outcomes of these patients. Three hundred seventy-two patients received microvascular decompression (MVD) under intraoperative electrophysiological monitoring in Nanjing Drum Tower Hospital in 2014; the characteristic AMR of HFS was observed in 359 patients during the operation. And the 359 patients were divided into two groups based on whether AMR had remained before the beginning of the decompression procedure for offending vessels. Thirty-three patients who showed a permanent disappearance of AMR before the beginning of decompression were regarded as group I. Dural opening and the succeeding CSF drainage produced a permanent disappearance of AMR in 13. During the dissection of lateral cerebellomedullary cistern, a permanent disappearance of AMR was found in 20 patients. Thirty-two patients were cured immediately; delayed resolution (7 days after surgery) was found in one patient. No complications were observed and no recurrence was found during the follow-up period in the 33 patients. In the other 326 patients (group II), AMR disappeared temporarily before the beginning of the decompression procedure for offending vessels in 42 patients. After decompression, AMR disappeared completely in 305 patients. Two hundred sixty-seven patients were cured immediately and 57 patients got a delayed resolution (2 days to 45 weeks after surgery). The two left did not get a complete abolition of spasm. Three cases of hearing loss, one hoarseness, and nine delayed facial paralysis were observed. The reason of early abnormal muscle response disappearance may be that the degree of neurovascular compression was not serious; these patients were more likely to get an immediate cure. Continuous intraoperative electrophysiological monitoring of AMR is necessary.

We retrospectively compared the outcome of microvascular decompression (MVD) for hemifacial spasm (HFS) associated with the vertebral artery (VA) with that of MVD for HFS unrelated to the VA. Between April 2008 and April 2015, 22 patients with VA-associated HFS underwent MVD at our institution. The median follow-up period was 28 months (range, 12-90 months). Results were classified as excellent in 19 patients (86 %), good in one (5 %), fair in one (5 %), and poor in one (5 %). Immediate complications developed in five patients (23 %), and one of these complications (5 %) was permanent. The surgical outcome of MVD for VA-associated HFS was similar to that of MVD for HFS unrelated to the VA; however, the incidence of complications was significantly more frequent in patients whose VA compressed the more proximal portion of the facial nerve root exit zone from the caudal side at the pontomedullary sulcus. We conclude that preoperative evaluation of VA compression patterns is important to predict the difficulty of the planned MVD procedure.

OBJECTIVE Hemifacial spasm (HFS) is a cranial nerve hyperactivity disorder characterized by unique neurophysiological features, although the underlying pathophysiology remains disputed. In this study, the authors compared the effects of desflurane on facial motor evoked potentials (MEPs) from the spasm and nonspasm sides of patients who were undergoing microvascular decompression (MVD) surgery to test the hypothesis that HFS is associated with a central elevation of facial motor neuron excitability. METHODS Facial MEPs were elicited in 31 patients who were undergoing MVD for HFS and were administered total intravenous anesthesia (TIVA) with or without additional desflurane, an inhaled anesthetic known to centrally suppress MEPs. All measurements were completed before dural opening while a consistent mean arterial blood pressure was maintained and electroencephalography was performed. The activation threshold voltage and mean amplitudes of the MEPs from both sides of the face were compared. RESULTS There was a significantly lower mean activation threshold of facial MEPs on the spasm side than on the nonspasm side (mean ± SD 162.9 ± 10.1 vs 198.3 ± 10.1 V, respectively; p = 0.01). In addition, MEPs were also elicited more readily when single-pulse transcranial electrical stimulation was used on the spasm side (74% vs 31%, respectively; p = 0.03). Although desflurane (1 minimum alveolar concentration) suppressed facial MEPs on both sides, the suppressive effects of desflurane were less on the spasm side than on the nonspasm side (59% vs 79%, respectively; p = 0.03), and M waves recorded from the mentalis muscle remained unchanged, which indicates that desflurane did not affect the peripheral facial nerve or neuromuscular junction. CONCLUSIONS Centrally acting inhaled anesthetic agents can suppress facial MEPs and therefore might interfere with intraoperative monitoring. The elevated motor neuron excitability and differential effects of desflurane between the spasm and nonspasm sides support a mechanism of central pathophysiology in HFS. Clinical trial registration no.: B2012:099 ( clinicaltrials.gov ).

Hemifacial spasm (HFS) is one of the most common presentations in patients with cranial psychogenic (functional) movement disorders (PMD). Medical records and videos of patients with PMD and HFS were reviewed to identify those with psychogenic HFS and to compare the phenomenology of psychogenic HFS with organic HFS. We identified 18 (9.8%) patients with psychogenic HFS from a cohort of 184 patients with PMDs. There were 14 (78%) women and 4 men, with a mean age at onset of 33 ± 13.5 years. These were compared with 37 consecutive patients with organic (primary) HFS. Patients with psychogenic HFS were significantly younger and had more frequently tonic muscle contractions, bilateral asynchronous hemifacial involvement, isolated lower facial involvement, downward deviation of the mouth's angle, and lack of the "other Babinski sign" compared to those with organic HFS. Other features such as ipsilateral downward movements of the eyebrow; associated tremor, dystonia and hemi-masticatory spasms were more frequently observed in patients with psychogenic HFS but these differences did not reach statistical significance. Lack of other Babinski sign and tonic muscle contractions showed the highest sensitivity (1.00 and 0.87, respectively), whereas downward mouth's angle deviation showed the highest specificity (1.00) for the diagnosis of psychogenic HFS. Besides other features such as suggestibility, distractibility, periods of unexplained improvements observed in most patients with PMDs, several clinical features, such as tonic muscle contractions, downward mouth's angle deviation, predominant lower facial and bilateral involvement, may be helpful in distinguishing psychogenic from organic HFS.