Characteristics of thyroid diameter and volume of children aged 8 - 10 years in Gansu Province / 中华地方病学杂志

ABSTRACT

Objective:To analyze the characteristics of thyroid diameter and volume of children aged 8 - 10 years in Gansu Province, and to provide a basis for standardizing B-ultrasound examination of children's thyroid volume and establishing a normal reference value of children's thyroid volume.Methods:The data of thyroid volume by B-ultrasound and urinary iodine determination of children aged 8 - 10 years in Gansu Province were from Institute of Endemic Disease, Gansu Center for Disease Control and Prevention. Based on the measured data of thyroid B-ultrasound of 8 - 10 years children in Gansu Province, the characteristics and relationship between thyroid diameter and volume were analyzed by nonparametric test.Results:The medians of urinary iodine of 8, 9, 10 years children ( n = 500, 503, 496) were 166.62, 167.16 and 178.78 μg/L, respectively. The length, width, thickness and volume of the left and right lobes of the thyroid in children were skewed distribution. There was a positive correlation between the left and right diameters (length, width and thickness) and between left and right thyroid volumes ( r = 0.76, 0.85, 0.72, 0.88, P < 0.001). There was no significant difference in the six diameter lines and volume values of thyroid between genders ( P > 0.05), but there was significant difference between ages ( P < 0.001). The means thyroid volume of 8, 9 and 10 years children were 2.6, 2.9 and 3.2 ml, respectively, the medians were 2.5, 2.7 and 3.0 ml, respectively, and the 97th percentile ( P97) were 4.4, 4.9 and 6.5 ml, respectively. The thyroid volume of 10 years group was higher than the current national standard (6.0 ml). The median ranges of thyroid volume of children aged 8, 9 and 10 years at the county level were from 1.8 ml to 4.1 ml, from 1.8 ml to 4.3 ml and from 1.9 ml to 4.4 ml, respectively. There was significant difference in thyroid volume of children at the county level in all age groups ( P < 0.05). Conclusions:Compared with the national standard, the P97 value of thyroid volume of children aged 8 - 10 years in Gansu Province is slightly different. The reference value of thyroid volume should be formulated according to age, and a unified reference value can be used for different genders at the same age.