OBJECTIVE: To evaluate the restoration of the ureter of the dog after resection of a 5 cm-long middle segment. MATERIALS AND METHODS: Eight dogs underwent resection of the middle segment of the ureter, after which a 6-8 F Bard ureteric stent modelling catheter was inserted into both remaining portions of the ureter for 3 months. One month after removal of the stent the animals were killed and their ureters examined both grossly and microscopically. Paraffin-embedded sections were subjected to microscopic and immunohistochemical studies. RESULTS: The continuity of the ureter was restored but the reconstructed segment was narrowed to a variable extent. The wall of the ureter was lined by normal urothelium but consisted of fibrous connective tissue which failed to produce a regular coat. The reconstructed segment showed no smooth muscle cells (negative staining with azan and a negative reaction with monoclonal antibodies against desmin). A few smooth myocytes were found only at the border with intact portions of the ureter. CONCLUSIONS: The surgical procedure resulted in the restoration of ureteric continuity by repair and not by regeneration of its wall.
OBJECTIVE: To evaluate the restoration of the ureter of the dog after resection of a 5 cm-long middle segment. MATERIALS AND METHODS: Eight dogs underwent resection of the middle segment of the ureter, after which a 6-8 F Bard ureteric stent modelling catheter was inserted into both remaining portions of the ureter for 3 months. One month after removal of the stent the animals were killed and their ureters examined both grossly and microscopically. Paraffin-embedded sections were subjected to microscopic and immunohistochemical studies. RESULTS: The continuity of the ureter was restored but the reconstructed segment was narrowed to a variable extent. The wall of the ureter was lined by normal urothelium but consisted of fibrous connective tissue which failed to produce a regular coat. The reconstructed segment showed no smooth muscle cells (negative staining with azan and a negative reaction with monoclonal antibodies against desmin). A few smooth myocytes were found only at the border with intact portions of the ureter. CONCLUSIONS: The surgical procedure resulted in the restoration of ureteric continuity by repair and not by regeneration of its wall.