Background/Objectives: For centuries, humans have employed animal models to progress biomedical science, to understand pathological and biological processes, and to develop and test drugs, vaccines, and surgical techniques. In the field of urology, Sampaio and his colleagues from Brazil were the pioneers in proposing that the porcine model is the most accurate representation of the human kidney. We aim to describe the relevant urinary anatomy of female Landrace pigs based on endoscopy and computed tomography (CT) scans and compare differences between the urinary anatomy of pigs and humans. Methods: Four white Landrace female pigs were used for the study: two for CT imaging and two for endoscopic assessment. CT-urograms were performed using a 64-channel tomography machine with 0.625 mm thick slices. For the endoscopic procedure, the intravaginal urethral meatus was cannulated using a cystoscope, followed by complete urethrocystoscopy. The ureteric orifices were then cannulated, and a retrograde pyelogram was performed, followed by ureterorenoscopy. The analyses were performed using SPSS (Version 28), and simulated data was created using R (version 3.5.0), with the significance set at p ≤ 0.05. The data obtained from two pigs was used to simulate an empirical data with 500 observations, using the mean and standard deviations from our n = 2 to produce a random normal distribution. Results: CT and endoscopic findings showed two multirenculate multipapillate kidneys, each receiving blood supply from a single renal artery that is further divided into cranial and caudal branches. The delayed phase of the urogram showed distal ureters passing posterior to the bladder and emptying into the bladder at the base. Urethroscopy revealed an intravaginal urethral meatus ventral to the anus, positioned midway between the mucocutaneous junction of the vulva and the cervix. Endoscopic view of the bladder neck showing patulous ureteric orifices at the bladder neck with no distinct interureteric ridge or trigone. Retrograde pyelogram showed a Group B drainage pattern in both pigs. Conclusions: While there are numerous similarities between the urinary systems of humans and pigs, there are important subtle differences that urologists and researchers need to be mindful of before using the porcine model for urological research and training.
John et al. (Tue,) studied this question.