title: Intra-operative neurophysiology during microvascular decompression for hemifacial spasm.
abstract: There is evidence that primary hemifacial spasm (HFS) in the majority of patients is related to a vascular compression of the facial nerve at its root exit zone (REZ). As a consequence, the hyperexcitability of facial nerve generates spasms of the facial muscles. Microvascular decompression (MVD) of the facial nerve near its REZ has been established as an effective treatment of HFS. Intra-operative disappearance of abnormal muscle responses (lateral spread) elicited by stimulating one of the facial nerve branches has been used as a method to predict MVD effectiveness. Other neurophysiologic techniques, such as facial F-wave, blink reflex and facial corticobulbar motor evoked potentials (FCoMEP), are feasible to intra-operatively study changes in excitability of the facial nerve and its nucleus during MVDs. Intra-operative neuromonitoring with the mentioned techniques allows a better understanding of HFS pathophysiology and helps to optimise the MVD.
authors.affiliation: Department of Intraoperative Neurophysiology, Hospital Universitari de Bellvitge, Feixa Llarga Ave., Barcelona 08907, Spain. isabelfc74@yahoo.es
authors.forename: I
authors.initials: I
authors.lastname: Fernández-Conejero
authors.forename: S
authors.initials: S
authors.lastname: Ulkatan
authors.forename: C
authors.initials: C
authors.lastname: Sen
authors.forename: V
authors.initials: V
authors.lastname: Deletis
mesh_terms: D001767:Blinking / Q000502:physiology; D019054:Evoked Potentials, Motor / Q000502:physiology; D005152:Facial Muscles / Q000294:innervation / Q000503:physiopathology / Q000601:surgery; D005154:Facial Nerve / Q000502:physiology / Q000601:surgery; D005260:Female; D019569:Hemifacial Spasm / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D008297:Male; D061145:Microvascular Decompression Surgery; D016343:Monitoring, Intraoperative / Q000379:methods; D009424:Nervous System Physiological Phenomena; D016896:Treatment Outcome