Postoperative Voice Changes Research Articles

Superior laryngeal nerve preservation in peri-apical surgery by mobilization of the viscerovertebral angle

Iatrogenic lesions of the superior laryngeal nerve (SLN) are much more common than is generally recognized. Since injury to this nerve may cause transient or even persistent changes either in quality of voice or in deglutition, an attempt should be made to localize and identify the nerve during surgery. This study included 74 patients who underwent surgical dissection near the thyroid apex in the neck. Effective prevention of SLN injury during surgery was achieved by anatomical localization of the nerve in the viscerovertebral angle and its functional identification with the nerve stimulator. Post-operative analysis consisted of subjective interview, rigid laryngoscopy, acoustic analysis, laryngeal videostroboscopy and cricothyroid electromyography. Four patients complained of post-operative voice changes; two were diagnosed as SLN injury (2.4 per cent), one as reflux laryngitis and the fourth as intubation granuloma. Surgical access to the SLN in the periapical area may be achieved through mobilization of the viscerovertebral angle. The use of a nerve stimulator during difficult situations should keep SLN injury at a minimum.

Voice changes and thyroid surgery: is pre-operative indirect laryngoscopy necessary?

Indirect laryngoscopy (IDL) is often performed prior to thyroid surgery to detect pre-existing vocal cord pathology. A retrospective chart review of 201 patients undergoing thyroid surgery at the Prince of Wales Hospital was undertaken in order to study the patterns of pre-operative and postoperative voice changes and IDL findings. A total of 9% of patients had pre-operative voice symptoms, and 22% of this group had abnormalities detected on pre-operative IDL. Of 160 documented IDL, 4% revealed vocal cord pathology in asymptomatic patients, including an asymptomatic recurrent laryngeal nerve palsy. Indirect laryngoscopy remains a useful but flawed pre-operative screening tool for patients with voice symptoms, but the literature suggests that more advanced phoniatric tests will provide superior diagnostic sensitivity. The role of routine pre-operative laryngoscopy for asymptomatic patients is of debatable value.

Surgical anatomy of structures adjacent to the thyroid apex and post-operative voice change (A review-including dissection)

Summary This paper considers the anatomy of structures contiguous to the upper pole of the thyroid gland. It also describes the findings of an anatomical dissection confined to the muscular andcarotid triangles of the neck with the nerves therein innervating the cricothyroid and infrahyoid muscles. The segmental nature of the latter is described. The variable course of the cricothyroid artery with regard to the sternothyroid muscle is noted. A superficially placed artery is accompanied by branches of the ansa cervicalis; a deeply placed one is related to the external laryngeal nerve. In addition to the external laryngeal nerve there are other nerves, including branches of the ansa cervicalis, which can be damaged during operations involving the thyroid apex or adjacent structures. A comment is made about the significance of these findings with particular reference to voice change.

Vocal cord paralysis following approaches to the anterior cervical spine.

AbstractThe charts of 85 patients who had undergone an approach to the anterior cervical spine between 1966 to 1970 were reviewed. Nine of them (11 percent) showed postoperative voice changes, three of those had permanent vocal cord paralysis. The possible causes of recurrent nerve damage are discussed.