19 Aug 2020
“These findings may function as a guiding rule… by providing an intraoperative measure of how likely re-obstruction and stricture formation is to occur” – Journal of Small Animal Practice editor Nicola Di Girolamo.
James Westgate
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Image © BSAVA
A new study has shown it may be possible to predict the likelihood of re-obstruction and stricture formation occurring following surgery in male cats.
The research, published in the latest issue of the Journal of Small Animal Practice (JSAP), evaluated urethral orifice cross-section dimensions and correlation with stricture formation following perineal urethrostomy.
Perineal urethrostomy is a procedure used to relieve urethral obstruction in male cats in which medical management had failed. In the procedure, a permanent new stoma is created in the pelvic urethra proximal to the obstruction.
In the study titled “Evaluation of urethral orifice cross-section dimensions following perineal urethrostomy in male cats”, 24 male cats with lower urinary tract disease underwent the procedure.
The urethral orifice cross-section was estimated by the largest urinary catheter that could be easily inserted through the stoma at three time points: preoperatively, intraoperatively and 12 days postoperatively.
Cases of obstruction recurrence and stricture were documented within the six-month follow-up period.
Uri Segal, corresponding author for the paper, said: “The intraoperative stoma ranged from 1Fr [French catheter scale] to 10Fr (median 10Fr) and the 12-day postoperative stoma ranged from 4Fr to 10Fr (median 8Fr). There was significant reduction of stoma size 12 days postoperatively, compared to the measurements taken intraoperatively.
“Post-surgical stricture formation and re-obstruction was documented in 5 of 24 (21%) cats. Obstruction recurrence is probable if the intraoperative stoma size is 8Fr or less. Furthermore, if the stoma size is 6Fr or less, re-obstruction is almost certain (all of these cases in the study were re-obstructions).
“Conversely, an intraoperative stoma of more than 8Fr had a low risk of recurrence.”
JSAP editor Nicola Di Girolamo added: “These findings may function as a guiding rule for surgeons performing perineal urethrostomy, by providing an intraoperative measure of how likely re-obstruction and stricture formation is to occur.
“It should be remembered, however, that the functional urethral stoma cross-section may vary during the urination cycle and the measurements in this study are likely to only represent a fraction of the functional urethral cross-section size.”
The full article can be found in the August issue of JSAP, which is free for BSAVA members. It can also be read online.
