Percutaneous Renal Access by Urologist or Radiologist: A Review of the Literature

Background: Percutaneous nephrolithotomy (PCNL) is the preferred treatment for renal calculi greater than 2cm in diameter. In both the United States and United Kingdom, interventional radiologists often perform percutaneous access rather than urologists obtaining their own access. Objectives: We present a local cohort of urologist versus radiologist obtained percutaneous access and a relevant literature review. In addition, access techniques and the role of training urologists to obtain percutaneous access are reviewed. Patients and Methods: The records of 233 patients undergoing PCNL at the University of Pittsburgh Medical Center (UPMC) between 2000 and 2008 were retrospectively reviewed. Patients were stratified according to percutaneous access by urologists (group 1) or a group of interventional radiologists (group 2) in 195 and 38 patients, respectively. Radiologist-acquired access was performed for collecting system decompression in 33.3% of patients in group 2. A predicted access difficulty score was calculated using demographic, stone, and operative variables. Percutaneous access complications and stone-free rates were compared between groups. A Medline search of pertinent articles was conducted. Additional sources were identified from the reference sections of relevant manuscripts. Results: Rates of stone clearance are superior with urologist-obtained renal access as compared to radiologist-obtained access when there is no preoperative communication between groups. Complication rates are similar between groups. Among urologists, the learning curve for PCNL is 60 cases for competence and 100-115 cases for excellence. Several models for virtual training in percutaneous renal access are available. The use of retrograde endoscopy can reduce the number of tracts required for access, thereby reducing perioperative blood loss. Ultrasound has been used as an adjunct imaging modality for PCNL and reduces the risk of radiation to patients and staff. Conclusions: Urologists can safely obtain percutaneous renal access. Further training during and after residency is necessary to increase the number of urologists capable of obtaining access for PCNL. A number of virtual models are available to facilitate training. Endoscopic-assisted percutaneous renal access may decrease the steep learning curve associated with obtaining percutaneous access. Efforts should be made to decrease the use of ionizing radiation during PCNL.