Urethrostomy is a surgical procedure that creates a permanent opening in the urethra, commonly to remove obstructions to urine flow. The procedure is most often performed in male cats, where the opening is made in the perineum. Urethrostomy is a surgical procedure that creates a permanent opening in the urethra, commonly to remove obstructions to urine flow. The procedure is most often performed in male cats, where the opening is made in the perineum. For many years perineal urethrostomy has been used in cattle, sheep and goats, especially young males that have been castrated at a young age, for obstruction by uroliths. However, the anatomy of the male cat is quite different and the urethra is very small in diameter. Perineal urethrostomy in the male cat was developed in 1962 and published in the Journal of the American Veterinary Medical Association in 1963. It was modified in 1967, and further modified in 1971.