OBJECTIVETo explore the protection methods of parathyroid glands (PTGs) and their functions during total thyroidectomy.

METHODSThe locations and the blood supplies of parathyroid glands in 292 cases underwent total thyroidectomy between February 1990 and December 2009 were studied. The protective measures for PTGs and their blood supplies during total thyroidectomy were analyzed.

RESULTSTotal of 542 superior PTGs and 467 inferior PTGs were found in 296 cases of total thyroidectomy. Of the superior PTGs, 444 (81.9%) consistently located in the back sides of the thyroid glands and at the level of inferior edge of thyroid cartilage. The locations of the inferior PTGs were variable, 231 (49.5%) of them located in the inferior 1/3 part of the back sides of the thyroids and 116 (24.8%) at the inferior thyroid, in where inferior thyroid artery (ITA) branches enter thyroid. The fine dissections showed that the blood supplies to superior PTGs were mainly from the upper branch of ITA, accounting for 71 (68.3%) of 104 superior PTGs and the blood supplies to inferior PTGs were from the inferior branches of ITA system, accounting for 114 (80.3%) of 142 inferior PTGs. There was 13 cases with short-term hypocalcemia postoperatively, but no case with permanent hypoparathyroidism.

CONCLUSIONSThe blood supplies of PTGs are associated with their locations. During total or subtotal thyroidectomy, parathyroid glands and their artery blood-supply should be exposed and preserved to prevent hypoparathyroidism after surgery.