1Department of Radiology, College of Medicine, Soonchunhyang University, Korea. 2Department of Radiology, Hanseo College Hospital, Korea.
Published online: September 1, 2001.
ABSTRACT
PURPOSE: The purpose of this study was to establish the sonographic measurement of normal thyroid gland in the neonates. MATERIALS AND METHODS: Ultrasonographic evaluation of the thyroid gland was performed in the first week of life in 107 term neonates. The serum level of thyroid stimulating hormone was normal in all neonates. Their gestational age at birth was range from 37 to 41 weeks and birth weight was 3305 +/-57.74 g. Sonography was performed with 7.5 MHz linear array transducer (SA-8800MT, Medison, Korea) within the first week of postnatal age. Maximal transverse (T), anteroposterior (AP), and longitudinal (L) dimensions of thyroid gland were measured. The volume of each lobe was estimated by using standard geometric formula; volume of a prolate elipsoid= T x AP x L x n/6. The total volume of the thyroid gland was calculated as the sum of the each lobe. Thecorrelations with total thyroid volume and weight, height, the body surface area, gestational age of the neonate were estimated by Pearson's coefficient and p value on Bivariate correlation analysis. RESULTS: Total thyroid volume was 0.68 +/-0.23 cm3, left and right lobe volumes of thyroid gland were 0.32 +/-0.12cm3 and 0.36 +/-0.14 cm3, respectively. T, AP, and L dimension of right lobe were 0.69 +/-0.14 cm, 0.71 +/-0.13cm, 1.37 +/-0.22 cm, espectively. And those of left lobe were 0.70 +/-0.11 cm, 0.65 +/-0.13 cm, 1.31 +/-0.21 cm,respectively. The Pearson's coefficients for total thyroid volume with the weight, and body surface area of neonate were 0.385, 0.395(p<0.05), respectively, representing ignificant correlation. CONCLUSION: The total thyroid volume of the term euthyroid neonate was 0.68 +/-0.23 cm3 and was significantly correlated with the weight and body surface area.