Assessment of Thyroid Gland Volume in A Healthy Adult Sudanese in Khartoum State using Ultrasonography

Abstract

This was cross sectional study aimed to establish a local reference of thyroid gland volume in Sudanese normal subjects using ultrasound, and to correlate the values with gender, age, weight and height. The study was done in Alrakha medical centre in Omdurman. The ultrasound system used was Mendray medical system, a grey scale real-time ultrasound machine, fitted with a 7.5 MHz linear transducer. The subjects were examined in supine position, with pillow placed under their shoulders to hyperextend the neck. US gel was applied over the thyroid area. The transducer was directly placed on the skin over the thyroid gland, and an image of each lobe was obtained in transverse and longitudinal planes. A total of 120 healthy subjects, 32 (26.7%) males and 88 (73.3%) females were comprised in the study. Thyroid volume was estimated using ellipsoid formula (the volume = length * width * depth *0.52), and the total thyroid volume obtained by adding the volume of both lobes. The mean age and range of the subjects was 35.85 ± 13.6 (18 –77) years; the mean body weight was (70.46 ± 15) kg, and mean height was (168± 8.6) cm. The overall mean volume ± SD volume of the thyroid gland for both lobes in all the patients studied was 7.56 ± 2.88 cm3. The mean volume for both lobes in females and males were 7.22 ± 2.7cm3 and 8.48 ± 2.94 cm3, respectively. The male's thyroid volume was greater than the females. The mean volume of the right and left lobes of the thyroid gland were 3.78 ± 1.5 cm3 and 3.49 ± 1.4 cm3 (in females) and were 4.55 ± 1.6cm3 and 3.6 ± 1.48 cm3 (in males) respectively. The right thyroid lobe volume was greater than the left. The study also shows there is a linear correlation between thyroid V gland volume with age, weight and height (significant correlation with weight and height). In conclusion the normal volume of the thyroid gland in normal adult Sudanese population in Khartoum state using ultrasound has been determined. It is hoped that this value will serve as a reference standard in ultrasonographic evaluation of the thyroid gland in Khartoum.