Microvascular Decompressive Surgery for Hemifacial Spasm

Study Overview
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Brief Summary
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Review the clinical outcomes of Micro vascular decompression of Hemi facial Spasm. Assess safety and efficacy of Micro vascular decompression. Improve the outcome of these patients and decease rate of recurrence and complications.

Detailed Description
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Hemi facial spasm (HFS), a term described in 1905 by Babinski but first reported by Schultz in 1875, is a highly morbid movement disorder characterized by intermittent involuntary movement of muscles innervated by the facial nerve. (HFS) affects roughly 10 in 100,000 individuals in fifth or sixth decades of life. Primary HFS is commonly attributed to vascular loops compressing the seventh cranial nerve at its exit zone from the brainstem. The facial nerve compression is thought to lead to ephaptic transmission and to hyperactivity of the facial nucleus, resulting in the involuntary facial movements. Secondary HFS frequently follows peripheral facial palsy or may arise from facial nerve damage produced by tumours, demyelinating disorders, traumatisms, and infections accounting for 1-2 & of HFS. Over four in five primary HFS cases involve either anterior or posterior inferior cerebellar artery as the primary offender although vertebral artery, multiple vessels and veins may be involved. EMG recordings confirm the diagnosis by showing a typical electrophysiological signature: clonic facial muscle contractions, hyperactivity, and synkinesis, lateral spread evoked responses. Imaging can be useful for confirming that HFS is primary in nature and due to a neurovascular compression. In most cases (95% of the patients) the compressive vessel, generally an artery, is seen on MRI combined with MR-Angiography (MRA). High resolution T2-sequence is to be used to get good delineation of the facial nerve. Many treatments for HFS have been reported, including pharmacological agents, botulinum toxin injection, facial nerve blockage, physical therapy, radiofrequency ablation, acupuncture, as well as facial nerve combing and microvascular decompression (MVD). However, while MVD is effective, there are still significant postoperative complications.

Official Title
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Microvascular Decompressive Surgery for Hemifacial Spasm: Nuances of Technique and Outcome

Conditions
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Hemifacial Spasm

Intervention / Treatment
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* Other: Microvascular Decompressive Surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Primary Hemi facial spasm Unilateral Adults 20-60 years Clinical Diagnosis confirmed by Facial Evoked potential & Neuroimaging Exclusion Criteria: Secondary Hemi facial spasm caused by intracranial masses or other lesions Recurrent Hemi facial spasm Patients who are unfit for any neurosurgical interventions.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Microvascular Decompressive Surgery|Microvascular decompression for hemifacial spasm|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Samsung Medical center Grading system for Severity of Hemifacial Spasm | Success rate by assessing the degree of hemifacial spasm pre and post-operative using the SMC grading system proposed by Lee et all | one month | 
| Hearing Affection | Audiometry: to detect the degree of post-operative hearing affection using WHO Grading system For Hearing Loss | one month | 
| Recurrence | Recurrence rate within the duration of follow up | Six Month | 
| Morbidity and mortality | Morbidity and mortality rates related to the procedure using modified Rankin Scale | Six Month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in facial evoked EMG | Detect the changes in facial evoked EMG preoperative and postoperative and its correlation to outcomes (esp. disappearance of lateral spread response) | one month |