What causes laryngeal hemiplegia?
The precise cause remains unknown. It appears that the nerve that supplies the laryngeal muscle, which is responsible for opening the arytenoid cartilage, becomes damaged. The nerves supplying the left and right sides of the larynx follow different courses although both start from the base of the brain, inside the skull. The nerve on the right travels more directly along the throat and to the muscles of the larynx. The nerve on the left side follows a considerably longer and more tortuous path; travelling down the neck and into the chest where it wraps around part of the heart before coming all the way back up to the larynx (hence its name recurrent left laryngeal nerve). This long pathway is thought to predispose to degeneration within the left nerve. Hence the left side of the larynx is more commonly affected than the right. So why is there controversy over scoping? Unfortunately, the diagnosis of laryngeal hemiplegia is not straightforward. There is a large grey area between what is
