Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-4
pubmed:dateCreated
1994-8-25
pubmed:abstractText
It is generally assumed that hemifacial spasm (HFS) is caused by vascular compression of the facial nerve at the root exit zone (REZ), but the mechanism for the development of HFS is not known. Evidence has been previously presented that the signs of HFS are caused by hyperactivity of the facial motonucleus that is caused by the irritation to the facial nerve from the vascular contact. This assumption has been supported by the finding that daily electrical stimulation of the facial nerve in the rat facilitates the development of an abnormal muscle response that is a characteristic sign of HFS in man and is an indication of an abnormal cross-transmission that makes it possible to elicit a contraction of muscles innervated by one branch of the facial nerve by electrically stimulating another branch of the facial nerve. In the present study we show that close contact between a peripheral branch of the facial nerve and an artery also facilitates the development of an abnormal muscle response, but only if the facial nerve has previously been slightly injured (by a chromic suture) at the location of the arterial contact. We also show that blocking neural conduction in the facial nerve proximal to the artificial vascular compression abolishes the abnormal muscle contraction, which supports the assumption that the anatomical location of cross-transmission that is causing the abnormal muscle response is central to the vascular compression, most likely in the facial motonucleus. These findings may explain why the facial nerve is only susceptible to vascular compression near its REZ, where an injury to its myelin is more likely to occur than where the nerve is covered with schwann cell myelin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0001-6268
pubmed:author
pubmed:issnType
Print
pubmed:volume
126
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
149-57
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Facial nerve demyelination and vascular compression are both needed to induce facial hyperactivity: a study in rats.
pubmed:affiliation
Department of Surgical Neurology, Yamagata University School of Medicine, Japan.
pubmed:publicationType
Journal Article