Objective To understand anatomy of parathyroid gland and explore its application value in protection of parathyroid gland function during thyroidectomy. Methods The literatures, which were associated with the parathyroid anatomy and hypoparathyroidism were collected. The origin, function, anatomical location, number, blood supply, lymphatic system of the parathyroid gland and its relationship with surrounding tissues of parathyroid gland and its clinical significance in the thyroidectomy, were reviewed. Results The position of the superior parathyroid gland was relatively constant, and the inferior parathyroid gland was more likely to be ectopic. The number of the parathyroid gland was uncertain. The mainstream view was that the arterial supply of the parathyroid glands was mainly ensured by the inferior thyroid artery, a few by anastomosis of the superior and inferior thyroid arteries, or by the superior thyroid artery. However, the alternative view was that the blood supply of the parathyroid gland was not mainly derived from the inferior thyroid artery. The parathyroid gland was not easily distinguished from the adipose tissue and lymph node. Whether there was an independent lymphatic system in the parathyroid gland was still controversial. In the thyroidectomy, the parathyroid gland and its blood supply were reserved or protected by distinguishing from the Zuckerkandl tubercle, recurrent laryngeal nerve, and parathyroid specific attachment fat, which were identified by utilizing of the nanocarbon, loupe magnification, etc.. Especially in the central lymph neck dissection, the main thyroid artery trunk and its important branches should be carefully dissected or retained through the gentle capsular dissection and the correct use of energy devices for vessel sealing. The parathyroid gland in situ was reserved according to the parathyroid type. If it was not possible to be preserved, the parathyroid autotransplantation was necessary during the thyroidectomy. Conclusions Understanding origin and location of parathyroid gland, it could provide a direction for searching parathyroid gland during thyroidectomy. Being familiar with blood supply of parathyroid gland makes it possible to protect blood vessel and preserve parathyroid gland. Gentle capsular dissection, rational use of energy device, and indocyanine green angiography seem to be more important. Number of parathyroid gland allows us to treat each parathyroid gland as the last one, if it is not preserved in situ , parathyroid gland need to be autografted to avoid hypoparathyroidism.
ObjectiveTo investigate the adequate surgical procedures for well-differentiated thyroid cancer (WDTC) located in the isthmus.MethodsNineteen patients with WDTC located in the isthmus were identified with WDTC and managed by surgery in Department of General Surgery in Xuanwu Hospital of Capital University from Jun. 2013 to May. 2018.ResultsAmong the nineteen cases, fifteen patients had a solitary malignant nodule confined to the isthmus, four patients had malignant nodules located separately in the isthmus and unilateral lobe. One patient received extended isthmusectomy as well as relaryngeal and pretracheal lymphectomy; six patients received isthmusectomy with unilateral lobectomy and central compartment lymph node dissection of unilateral lobe; four patients received isthmusectomy with unilateral lobectomy and subtotal thyroidectomy on the other lobe as well as central compartment lymph node dissection of unilateral lobe; seven patients received total thyroidectomy or isthmusectomy with unilateral lobectomy and nearly total thyroidectomy on the other lobe, as well as central compartment lymph node dissection of both sides; one patient received total thyroidectomy and central compartment lymph node dissection of both sides, as well as lateral thyroid lymph node dissection of both sides. The median operative time was 126 minutes (67–313 minutes), the median intraoperative blood loss was 30 mL (10–85 mL), and the median hospital stay was 6 days (4–11 days). Hypocalcemia occurred in 12 patients. There were no complications of recurrent laryngeal nerve palsy or laryngeal nerve palsy occurred. All the nineteen patients were well followed. During the follow up period (14–69 months with median of 26 months), there were no complications of permanent hypoparathyroidism occurred, as well as the 5-year disease-specific survival rate and survival rate were both 100%.ConclusionsFor patients with well-differentiated thyroid cancer located in the isthmus with different diameters and sentinel node status, individualized surgical procedures should be adopted.