Familial hemifacial spasm associated with arterial compression of the facial nerve. Case report

Exome Sequencing Implicates Impaired GABA Signaling and Neuronal Ion Transport in Trigeminal Neuralgia

Trigeminal neuralgia (TN) is a common, debilitating neuropathic face pain syndrome often resistant to therapy. The familial clustering of TN cases suggests that genetic factors play a role in disease pathogenesis. However, no unbiased, large-scale genomic study of TN has been performed to date. Analysis of 290 whole exome-sequenced TN probands, including 20 multiplex kindreds and 70 parent-offspring trios, revealed enrichment of rare, damaging variants in GABA receptor-binding genes in cases. Mice engineered with a TN-associated de novo mutation (p.Cys188Trp) in the GABA_A receptor Cl⁻ channel γ-1 subunit (GABRG1) exhibited trigeminal mechanical allodynia and face pain behavior. Other TN probands harbored rare damaging variants in Na⁺ and Ca⁺ channels, including a significant variant burden in the α-1H subunit of the voltage-gated Ca²⁺ channel Ca_v3.2 (CACNA1H). These results provide exome-level insight into TN and implicate genetically encoded impairment of GABA signaling and neuronal ion transport in TN pathogenesis.

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Genomic analysis of trigeminal neuralgia (TN) using exome sequencing

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Rare mutations in GABA signaling and ion transport genes are enriched in TN cases

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Generation of a genetic TN mouse model engineered with a patient-specific mutation

Microvascular decompression for familial hemifacial spasm : single institute experience

Objective

The purpose of this study was to evaluate the characteristics and surgical outcomes of familial hemifacial spasm (HFS) and to discuss the role of genetic susceptibility.

Methods

Between 2001 and 2011, 20 familial HFS patients with ten different pedigrees visited our hospital. The data from comprehensive evaluation of these patients, including clinical, radiological and electrophysiological data and surgical outcomes were reviewed to characterize familial HFS and to compare the characteristics between familial HFS and sporadic HFS.

Results

According to the family tree, the inheritance pattern was difficult to define clearly using these data. Radiologic findings suggested that the vertebral artery (VA) was a more frequent offender in familial HFS than in sporadic cases (35.0% vs. 10.0%, p<0.001). Chi-square test showed that there were no correlation between VA tortuosity and underlying morbidity such as diabetes or hypertension (p=0.391). Eighteen out of 19 patients who underwent microvascular decompression showed no residual spasm. Other features of familial HFS overlap with sporadic cases. These findings suggest that certain genetic susceptibilities rather than hypertension or diabetes may influence vascular tortuosity and HFS development.

Conclusion

In this study, familial HFS seems not so different from sporadic cases. Authors thought familial HFS could have heterogeneous etiology. Further study of familial HFS including clinical, anatomic, genetic, and molecular information may help identify a gene or trait that can provide insight into the mechanisms of sporadic and familial HFS.

The many faces of hemifacial spasm: differential diagnosis of unilateral facial spasms

Hemifacial spasm is defined as unilateral, involuntary, irregular clonic or tonic movement of muscles innervated by the seventh cranial nerve. Most frequently attributed to vascular loop compression at the root exit zone of the facial nerve, there are many other etiologies of unilateral facial movements that must be considered in the differential diagnosis of hemifacial spasm. The primary purpose of this review is to draw attention to the marked heterogeneity of unilateral facial spasms and to focus on clinical characteristics of mimickers of hemifacial spasm and on atypical presentations of nonvascular cases. In addition to a comprehensive review of the literature on hemifacial spasm, medical records and videos of consecutive patients referred to the Movement Disorders Clinic at Baylor College of Medicine for hemifacial spasm between 2000 and 2010 were reviewed, and videos of illustrative cases were edited. Among 215 patients referred for evaluation of hemifacial spasm, 133 (62%) were classified as primary or idiopathic hemifacial spasm (presumably caused by vascular compression of the ipsilateral facial nerve), and 4 (2%) had hereditary hemifacial spasm. Secondary causes were found in 40 patients (19%) and included Bell's palsy (n=23, 11%), facial nerve injury (n=13, 6%), demyelination (n=2), and brain vascular insults (n=2). There were an additional 38 patients (18%) with hemifacial spasm mimickers classified as psychogenic, tics, dystonia, myoclonus, and hemimasticatory spasm. We concluded that although most cases of hemifacial spasm are idiopathic and probably caused by vascular compression of the facial nerve, other etiologies should be considered in the differential diagnosis, particularly if there are atypical features.

Clinical assessment of patients with primary and postparalytic hemifacial spasm: a retrospective study

OBJECTIVE: To compared the clinical features of 373 patients with primary and postparalytic hemifacial spasm (HFS). METHOD: Data analyzed were gender, ethnicity, age at symptom onset, disease duration, affected side, distribution of facial spasm at onset, hypertension, family history of HFS, previous history of facial palsy and latency between facial palsy and HFS. RESULTS:The prevalence of patients with Asian origin was similar in both groups such as female/male ratio, mean age at symptom onset, disease duration, affected side and distribution at onset of facial twitching. The upper left side of the face was the main affected region at onset. Almost 40% of the patients in both groups had hypertension. A prevalence of vascular abnormalities on the posterior fossa was seen in 7% and 12.5% of both groups. CONCLUSION: The clinical profile and radiological findings of patients with primary and postparalytic HFS are similar. The association of hypertension with vascular abnormalities and HFS was not frequent.

Hemifacial Spasms and Involuntary Facial Movements. Role of Magnetic Resonance in the Diagnostic Work-up. A Case Report

Caution is required when dealing with patients presenting hemifacial spasm as the symptom is common to many disorders (tumours, herpes zoster, a frigore paralysis, neurovascular conflict…). Often no reasonable cause of the spasm is found, but treatment must be attempted because hemifacial spasm can be highly debilitating. We describe a case of hemifacial spasm, initially deemed idiopathic, in which MRI demonstrated neurovascular conflict as the cause. It is not always easy to find a clear MRI pattern, but if the scan identifies the tortuousness of the arteries in the vicinity of the VII nerve root exit, it is highly probable that this is the true cause of hemifacial spasm. Even when it is not possible to identify this pattern, neurovascular compression cannot be ruled out. The good results of microvascular decompression in patients without a typical MRI pattern suggest that MRI is specific, but not always sensitive. There is no consensus in the literature on the sensitivity of MRI in the detection of neurovascular compression and values vary widely. It is generally believed that experience and different performance of the MR systems strongly influence the diagnosis of neurovascular conflict.

Familial trigeminal neuralgia: case reports and review of the literature

The paroxysmal facial pain of trigeminal neuralgia is usually idiopathic, but familial cases have been described. We describe a family with apparent autosomal dominant transmission of trigeminal neuralgia. Our cases and a review of the literature suggest that the etiology of trigeminal neuralgia may be vascular compression of the fifth cranial nerve. Autosomal dominant vascular and epileptic disorders are reviewed, and possible relationships to familial trigeminal neuralgia are considered.

Microvascular decompression to treat hemifacial spasm: long-term results for a consecutive series of 143 patients

OBJECTIVE

The concept of neurovascular decompression for the treatment of hemifacial spasm is now widely accepted. In this study, we report our long-term results for 145 cases treated with this procedure.

METHODS

The results of 145 microvascular decompressions to treat hemifacial spasm (performed between 1980 and 1998) among 143 patients (62.2% female patients and 37.8% male patients; mean age, 54.5 yr) are presented. The onset of symptoms was typical in 95.9% of cases and atypical in 4.1%. Platysma muscle involvement was observed for 24.5% of patients, with a higher incidence among female patients (74.3%). Patients were monitored with annual questionnaires. Twenty-six patients were lost to follow-up monitoring, and 117 are still undergoing follow-up monitoring, with an average period of 9.6 years (range, 1-17.6 yr).

RESULTS

At discharge, 69 patients (59%) were spasm-free and 48 patients (41%) experienced further spasm. At 6 months, the number of spasm-free patients had increased to 108 (92.3%), whereas only 9 patients (7.7%) complained of hemifacial spasm; 44 patients were spasm-free at an average time of 15 weeks. In follow-up examinations (average period, 9.4 yr), 106 patients were spasm-free. Seven patients experienced only temporary relief, with recurrence after 4.5 years. Two patients were spasm-free after 4 or 6 weeks, and the recurrence of spasm was observed 1 year later. Two patients were never completely spasm-free. Among the patients who did not undergo previous surgery elsewhere, only two experienced recurrence.

CONCLUSION

Deafness was the main postoperative complication (8.3%); most of those cases (66%) occurred before the routine use of intraoperative evoked potential monitoring. Analysis of our series demonstrates that this surgical procedure involves very low risk, is well tolerated by elderly patients, is associated with very low recurrence rates, and is a definitive treatment for more than 90% of cases.

Hemifacial spasm: clinical findings and treatment

Hemifacial spasm (HFS) is a peripherally induced movement disorder characterized by involuntary, unilateral, intermittent, irregular, tonic or clonic contractions of muscles innervated by the ipsilateral facial nerve. We reviewed the clinical features and response to different treatments in 158 patients (61% women) with HFS evaluated at our Movement Disorders Clinic. The mean age at onset was 48.5+/-14.1 years (range: 15-87) and the mean duration of symptoms was 11.4+/-8.5 (range: 0.5-53) years. The left side was affected in 56% instances; 5 patients had bilateral HFS. The lower lid was the most common site of the initial involvement followed by cheek and perioral region. Involuntary eye closure which interfered with vision and social embarrassment were the most common complaints. HFS was associated with trigeminal neuralgia in 5.1% of the cases and 5.7% had prior history of Bell's palsy. Although vascular abnormalities, facial nerve injury, and intracranial tumor were responsible for symptoms in some patients, most patients had no apparent etiology. Botulinum toxin type A (BTX-A) injections, used in 110 patients, provided marked to moderate improvement in 95% of patients. Seven of the 25 (28%) patients who had microvascular decompression reported permanent complications and the HFS recurred in 5 (20%). Although occasionally troublesome, HFS is generally a benign disorder that can be treated effectively with either BTX-A or microvascular decompression.

[Familial hemifacial spasm: report of 2 cases]

The authors report the clinical and angiographical findings of two cases of familial hemifacial spasm. This is the fifth description in the literature and presents mother and daughter at the ages of 76 and 51 respectively, in whom the left side was affected. They underwent exams of angioresonance that showed dolichobasilar with left side origin in both patients. The exams also demonstrated postero-inferior cerebellar artery very developed and irregularities in the walls of the vertebral and basilar arteries suggestive of arteriosclerosis in the mother and slightly elongated intracranial vessels in the daughter. Literature review and etiology data of the hemifacial spasm are focused.

Hemifacial spasm: endoscopic vascular decompression

Sixty patients with primitive hemifacial spasm were treated by means of a minimally invasive retrosigmoid approach in which endoscopic and microsurgical procedures were combined. Intraoperative endoscopic examination of the cerebellopontine angle showed that for 56 of the patients vessel-nerve conflict was the cause of hemifacial spasm. The most common offending vessel was the posterior inferior cerebellar artery (39 patients), next was the vertebral artery (23 patients), and last was the anterior inferior cerebellar artery (16 patients). Nineteen of the patients had multiple offending vascular loops. In one patient, another cause of hemifacial spasm was an epidermoid tumor of the cerebellopontine angle. For three patients, it was not possible to determine the exact cause of the facial disorder. Follow-up information was reviewed for 54 of 60 patients; the mean follow-up period was 14 months. Fifty of the patients were in the vessel-nerve conflict group. Forty of the 50 were free of symptoms, and four had marked improvement. The overall success rate was 88%, and there was minimal morbidity (no facial palsy, two cases of severe hearing loss).

Distribution of amyloid bodies in the aged human vestibulocochlear nerve

We tried to elucidate the localization and distribution of amyloid bodies (Corpora amylacea) in the human vestibulocochlear nerve stained with luxol fast blue-periodic acid Schiff-hematoxylin using of a combination of an image analyzing computer system and a microscope fitted with a drawing tube. After having observed each section of the vestibulocochlear nerve from the brain stem to the fundus of the internal auditory meatus, we counted the numbers of amyloid bodies in three different parts for each of three corpses, and measured the areas. We found that amyloid bodies of the vestibulocochlear nerve are concentrated to the limiting glial portion of the nerve more than to the nerve parenchyma, and amyloid bodies are not seen in the vestibulocochlear nerve peripheral to the transitional zone. Our quantitative trial proved that the amyloid body was larger in the 8th decade than in the 6th or 7th decade of life.

Magnetic resonance tomographic angiography: diagnostic value in trigeminal neuralgia

A combination of MRI, MR angiography and MR tomographic angiography (MRTA) was used to study the relationship of the root exit zone of the trigeminal nerve to surrounding vascular structures in seven patients with trigeminal neuralgia (TN) and ten patients with no evidence at a lesion in this region. MRTA is the technique for showing the relationship between vessels, cranial nerves and brain stem. MRTA clearly demonstrated the presence of a vessel at the root exit zone of the trigeminal nerve in all patients with TN. In the ten other patients, examination of 20 trigeminal nerves revealed that only one nerve (5%) was in contact with a vessel at the root exit zone. This study supports vascular compression of trigeminal nerves as a cause of TN, and demonstrates the value of MRTA as noninvasive technique for demonstrating compression.

Gliosis of the eighth nerve transitional region in patients with cerebellopontine angle schwannoma

The central-peripheral transitional region (TR) of the eighth nerve root was obtained from 8 patients with cerebellopontine angle schwannoma and investigated by light microscopy, electron microscopy, and immunohistochemistry. As a control, the TRs of 6 autopsy patients without any otologic disease were studied. Astrocytic proliferation at the TR was more prominent in the schwannoma patients than in the normal controls. Mild gliosis of the mantle zone of the TR was found in 5 schwannoma patients and moderate gliosis was noted in 3. The distribution of capillaries at the TR differed between the schwannoma patients and the normal controls. In the schwannoma patients, capillaries were rarely found in the mantle zone of the TR but were densely clustered at the glial fringe zone, especially near its border with the peripheral nervous tissue. Stasis of the capillaries in the glial fringe zone was frequently noted. These histological findings may indicate the occurrence of gliosis in response to eighth nerve degeneration. We suggest that there is increased susceptibility of the eighth nerve to injury at the TR in patients with schwannoma.

Familial hemifacial spasm

Two brothers developed hemifacial spasm at 63 and 70 years of age. Spasms occurred on the left and right sides of the face, respectively. Computed tomography scan and magnetic resonance imaging failed to show any abnormality. In addition, a third sibling reported a history of a peripheral facial palsy, which remitted spontaneously without sequelae. This is the fourth description of familial hemifacial spasms. This family is unique in that hemifacial spasm presented on different sides in the two brothers, and involvement was limited to one generation. Age at onset was later than for other familial cases and similar to sporadic cases.

Magnetic resonance tomographic angiography in the investigation of hemifacial spasm

Magnetic resonance angiography (MRA), combined with submillimeter magnetic resonance tomographic angiographic sections (MRTA) showed vascular compression of the 7th cranial nerve or its root exit zone (REZ) in the brain stem in 24 of 37 patients (64.86%) with hemifacial spasm. MRA alone was positive for REZ compression in only 19 (51.4%) cases, while conventional MRI was even less revealing, only 10 (27%) cases being positive.

Hemifacial spasm: evaluation by magnetic resonance imaging and magnetic resonance tomographic angiography

We evaluated 37 patients with hemifacial spasm and 16 age-matched control patients with other neurological disorders using magnetic resonance (MR) imaging, MR angiography, and MR tomographic angiography. MR tomographic angiography is a new technique using computer reconstruction of MR angiographic images to create coronal angiotomes that display tissue and arterial structures on the same image. Twenty-four of 37 (64.9%) patients with hemifacial spasm had ipsilateral vascular compression of cranial nerve VII or the pons noted by this technique, whereas only 1 of 16 (6.3%) control patients had compression. MR imaging and MR angiography were less sensitive and less specific in evaluating for vascular compression. This study supports vascular compression of cranial nerve VII or the pons as a cause of hemifacial spasm, and demonstrates MR tomographic angiography's value as an excellent, noninvasive technique to demonstrate the compression.