Volumetric estimation of the prostate gland using computed tomography in normal beagle dogs

The purpose of this study was to determine and compare prostate size using ultrasound and computed tomography (CT). The prostate gland was evaluated in eight normal Beagle dogs. Length, depth, and width of the prostate gland were measured by ultrasound and volume of the prostate was obtained from the two ellipsoid formula (US1, US2). Height, length, width, area, and volume of the prostate gland were measured by CT. Ratios of prostatic height, length, and width to the sixth lumbar vertebral body length were calculated. There was no significant difference between the US1 and US2 method, and between US2 and CT method, respectively. The prostatic volume calculated by US1 method was significantly lower than those with CT (p = 0.029). The Upper limits of ratios of prostate length, height, and width to the length of the sixth lumbar vertebra were 1.3, 1.1, and 1.7, respectively. Among these prostate dimensions, prostate length and height could be a useful index in estimating prostate size regardless of body weight.