面肌痉挛怎样治疗

面肌痉挛如何治疗配图，仅供参考

TREATMENT
As is already well known,widely-accepted treatment modalities of HFS include injections of Botulinum toxin as less invasive procedure and microvascular decompression (MVD) as the definite treatment .
# Botulinum toxin A (BTX-A)
Botulinum toxin type A (BTX-A) injections have been widely accepted as a safe and efficacious modality for the treatment of both blepharospasm and HFS . BTX-A,which has been approved by Food and Drug Administration for HFS in U.S.,can be injected subcutaneously or intramuscularly into the involved facial muscles. At the early state of HFS,BTX-A injection is very attractive method because it is less invasive and easily approached by physicians. The onset of action is about 3 to 5 days and the mean duration of benefit is 3 to 6 months. Thus,patients require repetitive injections two to four times per year. Complications of BTX-A injection include ptosis,blurred vision,and diplopia that usually improve in days to weeks. Most common injection sites are pretarsal and preseptal portions. Cakmur et al. showed that pretarsal injections of BTX-A in patients with involuntary eyelid closure due to contractions of the orbicularis oculi muscle are associated with higher efficacy and lower frequency of complications than preseptal injections . Although BTX-A injection shows high success rate of treatment of HFS and blepharospasm,its substantial limitation is that it required repeat injection,which eventually lead to charge of high economic cost because of uncoverage under current national health insurance policy.
# Microvascular decompression (MVD)
Whereas Botulinum toxin injection does not provide long-term relief because of its temporary benefit,surgical treatment using MVD results in long-term relief of the symptoms in the majority of patients . The detailed surgical procedures are as follows.
Opening
The operation technique for MVD is variable according to the surgeons preference. For example,some authors favor supine position and others lateral decubitus position (it is so called "park-bench position") . In our series,all of the surgical procedures were performed via a lateral retrosigmoid suboccipital approach. The patient is placed in a lateral park bench position with the head rotated approximately 10 degrees away from the affected site and the vertex dropped 15 degrees toward the floor. A 20?25 mm sized craniectomy is performed with extension to the flat occipital squama inferiorly and the sigmoid sinus laterally,below the posterior end of the digastric notch on the mastoid process.
Intradural procedure
After the cisterna magna or lateral cerebellomedullary cistern is opened,the cerebellum gives way so that the VIIth to VIIIth cranial nerve complex can be approached with minimal use of brain retractors. Some drainage of CSF is necessary to minimize potential injury by placing the retractor on the cerebellum. After CSF is drained,a tapered retractor blade is placed over the previously placed rubber dam and cottonoid. After careful dissection of the arachnoid membrane and gentle retraction of the flocculus,the root exit zone (REZ) of the facial nerve can be visualized. A good access from below is of most importance,because most conflicts are located ventrocaudal to the facial exit zone at the brainstem . Jannetta et al. and Sindou et al. indicated that reaching the facial nerve along an infra-floccular route was important for two reasons; 1) Neurovacular conflicts are usually located ventro-caudally at the REZ,2) A lateral-to-medial retraction of the cerebellar hemisphere would exert stretching of the VIIIth nerve and lead to hearing loss .
To reduce the cerebellar retraction,according to Nakanishis approach,the operators head and the patients head are at the same height,and the operator can look at the surgical field through the microscope in a horizontal direction . The compressing vessel,so called offender,can be identified near to the REZ. Several pieces of Teflon sponge are placed between the compressing vessel and the REZ.
Microanatomical observations
In our accumulated experience of about 900 cases,we found that the patterns of neurovascular conflicts by offending vessels are so variable in each case. As anatomical variation of neurovascular conflicts could be observed in trigeminal neuralgia,we found that a variety of anatomical compressive patterns contributed to the neurovascular conflicts. In some instances,focal thick arachnoid band was often a major contributing factor to compression. In others,two or even three compressing vessels were often observed with a type of sandwich,branching vessels,or multiple perforating vessels (unpublished data,[Fig. 1](https://ncbi.nlm.nih.gov/pmc/articles/PMC2588188/figure/F1/) ). These findings were already mentioned by Sindou et al. and it could be the source of insufficient decompressive surgery and consequently surgical failure . However,no statistical significance was shown between variable neuro-vascular conflicts and clinical outcome.
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[Open in a separate window](https://ncbi.nlm.nih.gov/pmc/articles/PMC2588188/figure/F1/?report=objectonly) [Fig. 1](https://ncbi.nlm.nih.gov/pmc/articles/PMC2588188/figure/F1/)
Variable patterns on microanatomical findings of neurovascular conflicts. (Park et al. in processing). (A : thick arachnoid bands,B : branching vessels,C : sandwich vessels,D : small perforating vessels).
Closure
After the neurovascular decompression,the dura mater can be closed in the following fashion which was newly designed . Four to five interrupted stitches are made at intervals of 6-7 mm. Several pieces of muscle that have been obtained from the adjacent muscles can be interposed into the space between the stitches. The muscle piece should be small enough to enter the slit but large enough to fill the defect between the stitches . In cases where the mastoid cavity is opened,bone wax should be applied to completely seal the opened surface of the cavity. Cranioplasty is performed using polymethyl methacrylate (PMMA) bone cement according to the surgeons preference. No fixation device is necessary because of the bulky muscle groups placed over the lesion. Irrigation with droplets of papaverine solution (10% concentration) is used in all cases as routine during surgical dissection of the neurovascular conflict and before closing of the dura mater.","department":"