Ultrasonographic measurement of the prostatic dimension-to-aortic luminal diameter in healthy intact male dogs and dogs with benign prostatic hyperplasia.

Objectives: To establish ultrasonographic measurements of the prostatic dimension-to-aortic luminal diameter ratios including the prostatic volume-to-aortic luminal diameter ratio in healthy, intact male dogs and compare these ratios between healthy dogs and dogs affected by benign prostatic hyperplasia.

Materials and methods: Healthy dogs (n = 75) and dogs affected by benign prostatic hyperplasia (n = 104) were included in the study. Prostate length, width, average height and aortic luminal diameter were measured from ultrasonographic images. In addition, prostatic volume was calculated, and prostatic volume-to-aortic luminal diameter were also compared.

Results: In healthy dogs, aortic luminal diameter was significantly associated with bodyweight and the prostatic width while body condition scores, prostate length and prostatic average height were not associated. Prostatic dimension-to-aortic luminal diameter ratios and prostatic volume-to-aortic luminal diameter ratio was not significantly different among dogs with different body condition scores either in healthy dogs or dogs affected by benign prostatic hyperplasia, except prostatic volume-to-aortic luminal diameter ratio in benign prostatic hyperplasia. Prostatic dimension-to-aortic luminal diameter ratios were significantly higher in benign prostatic hyperplasia while prostatic volume-to-aortic luminal diameter ratio significantly higher in healthy dogs. Prostatic dimension-to-aortic luminal diameter ratios demonstrated medium to high sensitivity and specificity when distinguishing between healthy dogs and dogs affected by benign prostatic hyperplasia. Prostatomegaly, should be considered when the prostatic dimension-to-aortic luminal diameter ratios increase. The calculated cut-off values were 3.68, 4.46 and 3.06 for prostate length-to-aortic luminal diameter, prostatic width- to-aortic luminal diameter and prostatic average height-to-aortic luminal diameter, respectively.

Clinical significance: The prostatic dimension-to-aortic luminal diameter ratios could be useful to evaluate the size of the prostate in dogs, as it is unaffected by the body condition scores.