Nephroscopy sheath characteristics and intrarenal pelvic pressure: human kidney model.

We developed an in vitro human kidney model to study the intrarenal pelvic pressures generated during percutaneous nephroscopy. Higher intrapelvic pressures were associated with nephroscopy sheaths of smaller caliber and greater length. In addition, the position of the sheath within the kidney markedly influenced intrapelvic pressure. The results of this study have influenced our practice and are especially important during cases involving percutaneous removal of infected urinary calculi and transitional-cell carcinoma.