MRI Investigation of Kidneys, Ureters and Urinary Bladder in Rabbits

Twelve clinically healthy and sexually mature New Zealand White rabbits were studied. The non-contrast imaging included T1-weighted and T2-weighted spin-echo and gradient-echo sequences in the transverse, sagittal and dorsal planes. Transverse MRI (T2-weighted image) through L1 demonstrated only the right kidney. The transverse T2-weighted image through L2 showed both kidneys. The cranial part of the urinary bladder on T1-weighted transverse scans through L4 was flexed to the left. The T2-weighted sagittal image 30 mm to the right of the median plane showed the right kidney, the right ureter and the urinary bladder. The T2-weighted sagittal image 30 mm to the left of the median plane showed part of the left kidney, the left ureter and the urinary bladder. The T2-weighted sagittal image 45 mm to the left of the median plane presented the lateral part of the left kidney. The dorsal MRI image (T2-weighted sequence) through the horizontal plane 30 mm ventral to the spine demonstrated the whole organs. These data will be useful in imaging anatomy and diagnostic studies of various pathologies of the excretory system in rabbits and other mammalian species.

Diagnostic Imaging of the Renal System in Exotic Companion Mammals

Radiographs can be used to easily visualize common types of urinary calculi in all parts of the urinary tract. Positive-contrast excretory urography and cystourethrography are sensitive to diseases within the ureters and urethra, most commonly obstruction. Ultrasound is widely available and noninvasive and can be used to evaluate renal architecture, ureteral dilation, urinary bladder wall disease, and urolithiasis. Computed tomography is increasing in availability and provides a large amount of cross-sectional information quickly and noninvasively. Multiple imaging modalities can be used to estimate or quantify glomerular filtration rate.

640-slice DVCT multi-dimensionally and dynamically presents changes in bladder volume and urine flow rate

The present study aimed to explore the application of 640-slice dynamic volume computed tomography (DVCT) to excretory cystography and urethrography. A total of 70 healthy subjects were included in the study. Excretory cystography and urethrography using 640-slice DVCT was conducted to continuously record the motions of the bladder and the proximal female and male urethra. The patients' voiding process was divided into early, early to middle, middle, middle to late, and late voiding phases. The subjects were analyzed using DVCT and conventional CT. The cross-sectional areas of various sections of the male and female urethra were evaluated, and the average urine flow rate was calculated. The 640-slice DVCT technique was used to dynamically observe the urine flow rate and changes in bladder volume at all voiding phases. The urine volume detected by 640-slice DVCT exhibited no significant difference compared with the actual volume, and no significant difference compared with that determined using conventional CT. Furthermore, no significant difference in the volume of the bladder at each phase of the voiding process was detected between 640-slice DVCT and conventional CT. The results indicate that 640-slice DVCT can accurately evaluate the status of the male posterior urethra and female urethra. In conclusion, 640-slice DVCT is able to multi-dimensionally and dynamically present changes in bladder volume and urine flow rate, and could obtain similar results to conventional CT in detecting urine volume, as well as the status of the male posterior urethra and female urethra.