If extensive ischemia or necrosis is the result of an injury, the
ureter injury is best treated by excising the injured segment of the
ureter and reestablishing continuity with the urinary system. If the ureteral injury occurred above the pelvic brim, the simplest reconstruction is a ureteroureterostomy, a procedure that is indicated for injuries to short segments of the ureter (ie, <2 cm), in which an anastomosis is performed between the 2 cut edges of the ureter"
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