According to a study published Online First today by Archives of Otolaryngology Head and Neck Surgery, one of the JAMA/Archives journals – During thyroidectomy (surgery to remove the thyroid gland), the technique surgeons use to detect a crucial nerve seems to make a difference in terms of complications, such as impairment of the parathyroid glands.
Thyroidectomy is a common operation according to background data in the study. However, it can be linked with major complications: paralysis of the recurrent laryngeal nerve (RLN, a nerve that transmits motor function and sensation to the larynx, or voice box) and hypoparathyroidism (caused by injury to the parathyroid glands). In 1-2% of cases, nerve paralysis is reported to be caused due to unintentional damage to the RLN during surgery. Temporary or permanent hypoparathyroidism may be caused due to extensive searching for the RLN during surgery. The researchers note two ways of identifying the RLN: one approach locates the nerve where it enters the larynx (superior-inferior direction), and the other locates the nerve in the trachea-esophageal groove, and traces it in the superior direction (inferior-superior direction).
To compare both techniques, an investigation was conducted by Bayram Veyseller, M.D., from Bezmialem Vakif University, Istanbul, Turkey, and colleagues. They examined patients undergoing partial or total thyroidectomy between January 2006 and August 2009. In 128 patients, the inferior-superior technique was used, and in 67 patients, the superior-inferior RLN identification method was used, according to the attending surgeons preference. In the first day after surgery the investigators analyzed patients vocal cord function and blood calcium levels. Until patients calcium levels improved, follow-up was conducted every three months, for an average of 26 months. Conditions were considered permanent if after one year blood calcium levels were still low (a sign of hypoparathyroidism) or RLN paralysis did not improve.
In the superior-inferior group no patients were affected with permanent paralysis of the RLN, however, in the other group permanent paralysis of RLN occurred in two patients. Hypoparathyroidism was temporary in four patients among the superior-inferior group and permanent in none. In the inferior-superior group patients, 14 experienced temporary hyperthyroidism and four experienced permanent. Overall, significantly fewer complications were found in terms of RLN paralysis and hypoparathyroidism in the superior-inferior group.
The researchers concluded, significantly lower rates of RLN paralysis and hypoparathyroidism were observed in thyroidectomies using a superior-inferior approach, adding that more investigations should be conducted to corroborate these results.
Written by Grace Rattue