Otolaryngology–Head and Neck Surgery Outcomes
Thyroid and Parathyroid Surgery
Preservation of recurrent laryngeal nerves
One of the most common complications of thyroid and parathyroid surgery is injury to the recurrent laryngeal nerve (RLN), which sits next to the thyroid. Injury to the RLN, which controls the voice box, can result in voice loss, inability to swallow and, if bilateral, inability to breathe with need for a tracheotomy.
Surgeons in the Division of Thyroid and Parathyroid Endocrine Surgery have participated in the development of national guidelines created to optimize the preservation of the RLN during thyroid and parathyroid surgeries1.
98.5-to-99.6 percent of patients treated at Mass Eye and Ear had voice and laryngeal assessments prior to surgery compliant with existing national guidelines for this metric. 99-to-99.6 percent of patients were found to have normal voice or laryngeal assessments after surgery consistent with successful RLN preservation.
Percentage of patients with normal voice / laryngeal exam (all surgeries)
Parathyroid hormone levels (PTH) after thyroid surgery
The four parathyroid glands, which are adjacent to the thyroid gland, are frequently injured during thyroid surgery. This occurrence is referred to as hypoparathyroidism.
Hypoparathyroidism has been associated with increased risk of renal insufficiency, the development of secondary malignancies, increased cardiovascular disease and increased risk of mortality2. In patients undergoing a thyroidectomy, national and international large databases suggest permanent hypoparathyroidism may occur in approximately 10 percent of patients. A measure of preserved parathyroid function is normal parathyroid hormone levels (PTH) after surgery.
The mean PTH level in Mass Eye and Ear patients undergoing total thyroidectomy was 34.9 pg/mL, which was consistent with normal postoperative parathyroid function in these patients.
Mean parathyroid hormone levels in patients undergoing thyroid surgery (pg/mL)
Calcium levels after parathyroid surgery
Hyperparathyroidism is a common condition of excess parathyroid function caused by one or more enlarged glands secreting more PTH than necessary for normal calcium hemostasis. As a result, calcium levels rise and can be associated with the development of kidney stones, severe osteoporosis or dangerous elevation of calcium level. Such patients generally undergo surgery to remove the gland, or glands, causing the elevation of PTH.
One quality measure of surgery is the occurrence of normal calcium levels after the procedure. At Mass Eye and Ear, patients who underwent parathyroid surgery for hyperparathyroidism had average postoperative calcium levels ranging from 9.7-to-9.8 pg/dL, which are within normal ranges in these patients.
Mean calcium level in patients undergoing parathyroid surgery (mg/dL)
- Chandrasekhar S, Randolph GW, Seidman MS, Rosenfeld R, Angelos P, Barkmeier-Kraemer J, S. Benninger M, Blumin J, Dennis G, Hanks J, Haymart M, Kloos RT, Seals B, Schreibstein J M, Thomas T M, Waddington C, Warren B, Robertson PJ American Academy of Otolaryngology Head and Neck Surgery Clinical Practice Guideline: Improving Voice Outcomes after Thyroid Surgery. Otolaryngol Head Neck Surg. 2013 Jun; 148 (6 Suppl): S1-37.
- Bergenfelz A, Nordenstrom E, Almquist M Morbidity of in Patients with Permanent Hypoparathyroidism after Total Thyroidectomy. Surgery 2020 167 124- 128