Consequences to the upper urinary tract after ureteric torsion.

Area of Science:

• Urology
• Surgical Research
• Animal Models

Background:

• Ureteric torsion is a rare condition.
• Understanding its effects on the upper urinary tract is crucial for surgical management.

Purpose of the Study:

• To investigate the impact of ureteric torsion on the upper urinary tract in a porcine model.
• To determine the threshold for obstruction and histological changes associated with ureteric torsion.

Main Methods:

• Eight pigs were used to model ureteric torsion.
• Distal ureter torsion (1-5 twists) and proximal ureter torsion (1-3 twists) were performed.
• Surgical reimplantation and re-anastomosis were utilized, followed by functional and histological assessment.

Main Results:

• Distal ureter torsion of 1-2 twists did not cause obstruction.
• Proximal ureter torsion of 360 degrees (1 twist) led to mechanical obstruction and dysfunction.
• Ischaemic changes were observed only after multiple torsions in histological examinations.

Conclusions:

• Proximal ureter torsion is more susceptible to causing obstruction than distal ureter torsion.
• Significant ureteric dysfunction can result from relatively minor degrees of proximal ureter torsion.
• Histological evidence of ischaemia requires substantial torsion, suggesting a high tolerance to torsion in the absence of mechanical obstruction.