草鹿 元

Purpose: Laryngeal framework surgery is usually performed under local anesthesia but cannot be tolerated by some patients. To develop a new procedure for these patients, we evaluated voice outcomes after arytenoid adduction combined with medialization laryngoplasty under general anesthesia using a laryngeal mask airway (LMA) for unilateral vocal cord paralysis. Materials and Methods: Eleven consecutive patients with severe unilateral vocal cord paralysis, with a maximum phonation time of less than 5 seconds, underwent arytenoid adduction combined with medialization laryngoplasty under general anesthesia using an LMA. Each paralyzed vocal cord was observed by intraoperative videolaryngoscopy. The vocal cord was moved to the position where the best vocal outcome could be expected, according to 3 parameters obtained from glottal images. Results: All patients achieved a maximum phonation time of more than 11 seconds. The mean airflow rate, which ranged from 550 to 1000 mL/s before surgery, improved to less than 390 mL/s. Perceptual evaluation using the grade, roughness, breathiness, asthenia and strain scale also improved significantly. Conclusions: These results were equivalent to those of previous reports of surgeries performed under local anesthesia. Intraoperative endoscopic vocal cord observation through the LMA may have contributed to the positive results. (C) 2012 Elsevier Inc. All rights reserved.

A 54-year-old man presented with an intracranial schwannoma of the hypoglossal nerve between the medulla and the left hypoglossal canal. The condylar fossa approach was used with intra-operative electromyography (EMG) monitoring of the lower cranial nerves. The tumor was then removed carefully without decreasing the tongue EMG responses. EMG monitoring enabled us to remove the tumor while maintaining the function of the hypoglossal nerve. Tongue EMG was easily recorded by stimulating the hypoglossal nerve fibers, which was useful in identifying the hypoglossal nerve and evaluating its function. This suggests that tongue EMG is a useful monitoring tool to enhance neurological outcome following removal of tumors in this region. (C) 2009 Elsevier Ltd. All rights reserved.

Botulinum toxin type A (BTX) injection into the orbicularis oculi muscle is an effective treatment for patients with hemifacial spasm (HFS). The objectives of this study were to investigate the effect of this treatment on HFS, in particular the associated hyperexcitability of the facial motor nucleus, and to discuss the potential mechanism of HFS. F waves in the mentalis muscle were examined before, 2 and 6 weeks after the BTX treatment of only the orbicularis oculi muscle in ten patients with HFS. F/M ratio, duration of F waves and frequency of F waves decreased significantly after the BTX treatment compared with those before the BTX treatment. These findings demonstrate that the excitability of the facial motonucleus decreases after BTX treatment of the orbicularis oculi muscle. From these results, we hypothesize that the trigeminal afferent input and the cortical control contribute to the hyperexcitability of the facial motor nucleus in patients with HFS. This warrants further investigation into the pathophysiology of HFS.