Ultrasonic characteristics of normal parathyroid glands and their clinical significances / 肿瘤研究与临床

ABSTRACT

Objective To investigate the location, size, ultrasonic characteristics and clinical significances of normal parathyroid glands. Methods A total of 350 healthy subjects with no relevant diseases in Shanxi Provincial Cancer Hospital from January 2017 to December 2017 were selected. The age ranged from 9 to 83 years old. They were divided into seven groups according to age, with 50 in each group. The position, size, shape, echo, boundary, and blood flow signal characteristics of the normal parathyroid glands in these healthy subjects examined by ultrasound were retrospectively analyzed, and the differences among the different groups were compared. Results The detection rate of normal parathyroid glands in 350 subjects was 95.4％ (1335/1400). The normal parathyroid glands were oval, fusiform or irregular shape hyperechoic or isoechoic nodules, with homogeneous echoes and clear borders. There was no obvious blood flow signal in most glands. The proportion of fusiform shape in upper parathyroid glands (24.4％, 161/659) was higher than that in lower parathyroid glands (18.4％, 125/676), the difference was statistically significant (χ2=6.99, P< 0.05). The superior parathyroid gland was mainly located in the superior thyroid region, while the inferior parathyroid gland was mainly located in the inferior thyroid region, especially within the range of 2 cm from the inferior thyroid pole. In the age ≤ 20 years old group, the proportion of patients with upper parathyroid gland in the upper thyroid region (80.4％, 74/92) was higher than that in the other age groups, and the proportion of patients with lower parathyroid gland in the subthyroid region (30.6％, 30/98) was higher than that in the other age groups, the difference was statistically significant (χ2= 3.35, P< 0.05). There was no significant difference in the size of parathyroid gland among different age groups (P> 0.05). Conclusions The detection rate of normal parathyroid glands is high, and they mainly located in the upper and lower thyroid regions within 2 cm from the lower margin of the thyroid. Ultrasound images are mainly characterized by the clear elliptical shape and the uniform high echo. The ultrasonic characteristics of normal parathyroidglands are conducive to preoperative localization of parathyroid glands and provides a reliable basis for finding and retaining parathyroid glands in thyroid surgery.