首页   按字顺浏览 期刊浏览 卷期浏览 Stretching of the Mueller Muscle Results in Involuntary Contraction of the Levator Musc...
Stretching of the Mueller Muscle Results in Involuntary Contraction of the Levator Muscle

 

作者: Kiyoshi Matsuo,  

 

期刊: Ophthalmic Plastic and Reconstructive Surgery  (OVID Available online 2002)
卷期: Volume 18, issue 1  

页码: 5-10

 

ISSN:0740-9303

 

年代: 2002

 

出版商: OVID

 

数据来源: OVID

 

摘要:

Purpose:Since the levator muscle involuntarily and tonically contracts against the weight and elastic resistance of the upper eyelid to maintain an adequate visual field, a mechanoreceptor such as a muscle spindle or a periodontal mechanoreceptor is thought to be essential for its functioning. It was surmised that the Mueller muscle might act as a serial kind of muscle spindle of the levator muscle.Methods:The response of the bilateral levator muscles evoked by stretching the Mueller muscle of each eyelid of 87 patients with dermatochalasis or aponeurotic blepharoptosis was electromyographically and photographically recorded.Results:Stretching of the unilateral Mueller muscle evoked contraction of the ipsilateral levator muscle in 18 and of the bilateral levator muscle in 69 of the 87 patients.Conclusions:The Mueller muscle can be thought of as a large, serial kind of muscle spindle, so that stretching by voluntary phasic contraction of the levator muscle for initial eye opening may evoke an afferent impulse to the mesencephalic trigeminal nucleus. Subsequently, this nucleus may stimulate the central caudal nucleus of the oculomotor nuclear complex, leading to involuntary tonic contraction of the ipsilateral or bilateral levator muscles, in the form of a continuous stretch reflex, to maintain an adequate visual field.

 

点击下载:  PDF (483KB)



返 回