Intra- and Inter-observer Variability of Computed Tomographic Measurements of the Prostate Gland in Neutered Dogs

Digital postprocessing analysis of prostatic perfusion in neutered dogs

B-mode ultrasound is routinely performed to evaluate the prostate gland in neutered dogs, although, the detection of malignancies may be challenging. Contrast-enhanced ultrasound (CEUS) has shown to be useful for the assessment of prostatic perfusion in normal and diseased dogs, although the interpretation of contrast ultrasonographic features may still be subjective. A quantitative tool for evaluating prostatic perfusion might improve the reliability of the results in terms of early detection of prostate neoplasia in neutered dogs. The present study aimed to evaluate the applicability of a postprocessing analysis tool to CEUS of the prostate in healthy neutered dogs, to provide quantitative measurements, and to study the influence of individual characteristics on prostatic regression. Twenty-three neutered dogs underwent a B-mode and CEUS examination of the prostate to acquire data about prostatic morphology and microcirculation. The prostate was imaged using a 5-7.5 MHz linear transducer and contrast was administered intravenously. Videoclips were analyzed by using Qontrast software and a postprocessing digital analysis tool (ImageJ) to measure perfusion peak intensity, time to peak, and vascularization ratio at the moment of the peak, which were then related to body weight, age, and time elapsed since orchiectomy. Correlation tests revealed higher vascularization in younger compared with older dogs (P < .05) and in smaller compared with larger dogs (P < .05). Time elapsed since orchiectomy (P > .05) did not affect prostatic perfusion. Contrast-enhanced ultrasound and the postprocessing analysis tool ImageJ allowed analysis of vascular perfusion in all dogs and have the potential to improve the diagnostic possibilities for andrological examination.

Ultrasonographic measurements of the prostate gland in castrated adult dogs

Background

The dimensions of the prostatic gland in castrated adult dogs, as assessed by ultrasonography, is currently not yet reported in veterinary literature. The current study was aimed at reporting the prostatic dimensions in castrated dogs and investigate the relationship between the dogs’ body weight and prostate size. A second aim of the study was to investigate whether there was a relationship between the dogs’ age and prostate dimensions. A prospective, single-centre, observational study was conducted and 72 privately owned, adult, male castrated dogs with a range of breeds and ages met the final inclusion criteria. The subjects were divided into three categories based on body weight.

Results

A Kruskal–Wallis test found prostatic length and prostatic depth in the longitudinal orientation to be significantly different among the 3 categories (P < 0.005), with an increase in both prostatic length and prostatic depth with increasing body weight. Linear regression of the data set provided comprehensive formulas calculating prostatic length and depth based on the body weight of the dog (r² of 0.69 and 0.53 for prostatic length and depth respectively). Kendall’s Tau rank test showed no correlation between dogs’ age and prostate dimensions (P > 0.100).

Conclusions

The current study is the first to provide a comprehensive, weight-based reference for the canine prostate gland of castrated dogs when assessed on ultrasonography.