Category: Clinical Stones: PCNL

MP7-3 - Comparison Of Conventional Bulls-eye, The Laser Direct Alignment Radiation Reduction Technique And A Novel Low-Radiation Targeting Needle During Percutaneous Renal Access: A Bench-Top Model

Fri, Sep 21
10:00 AM - 12:00 PM

Introduction & Objective :

Cumulative radiation exposure during percutaneous nephrolithotomy (PCNL) can result in the development of radiation-induced complications. We have previously described the laser direct alignment radiation reduction technique (DARRT) to reduce radiation exposure when obtaining renal access for PCNL. The purpose of this study was to compare the laser DARRT to a novel low-radiation targeting (LRT) needle technique and a conventional bulls-eye technique.


Methods :

The laser DARRT employs a laser beam and pulsed fluoroscopy to guide renal access. The LRT needle uses a specialized radiodense ring targeting system to facilitate use of low radiation settings. Conventional needle access utilizes continuous fluoroscopy. Twenty two subjects (6 attendings, 6 residents, and 10 medical students) accessed the upper, middle, and lower poles of a phantom renal model with each of the three techniques. The primary endpoint was total fluoroscopic time and secondary endpoints were total needle insertion time, number of punctures, and number of course corrections. Comparison between groups was performed using a one-way ANOVA with p<0.05 indicating significance.


Results :

Compared to conventional access (22.0 s), a significant reduction in fluoroscopy time was seen for the laser DARRT (2.2 s) and LRT needle (3.5 s; p<0.0001). This reduction in fluoroscopic time was seen in all three subject groups (p<0.0001). There was no significant difference between the three access techniques in the number of course corrections (p=0.24) or number of punctures needed to reach the calyx (p=0.63). Total access time varied by group but was not significantly different for attendings (p=0.82) or residents (p=0.23) between techniques. Needle insertion time for students was faster in the conventional needle technique (25.7 s) compared to the LRT needle (33.2 s) and laser DARRT (36.8 s; p=0.014).


Conclusions :

Total mean fluoroscopy time was reduced by 89.8% with the laser DARRT and 81.8% with the LRT needle compared to conventional needle access. These low-radiation access techniques can reduce the risk of radiation exposure to patients and staff during PCNL without increasing the length of time, course corrections, or number of punctures for residents or attendings.

Mohammad Hajiha

clinical instructor
LOMA LINDA UNIVERSITY MEDICAL CENTER│Department of Urology
Loma Linda, California

Michael Wilkinson

Loma Linda, California

Jonathan Ewald

Loma Linda, California

Shawn Engelhart

Loma Linda, California

Hillary Wagner

Loma Linda, California

Muhannad Alsyouf

Resident Physician
LOMA LINDA UNIVERSITY MEDICAL CENTER │ Department of Urology
Loma Linda, California

Urology Resident at Loma Linda University Medical Center, California USA

Milan Shah

Loma Linda, California

Samuel Abourbih

Loma Linda, California

Akin Soner Amasyali

Loma Linda, California

Duane D. Baldwin

Professor, Director of Urologic Research
Loma Linda University Medical Center
Loma Linda, California

Dr. Duane Baldwin is Professor of Endourology and Director of the Endourology Fellowship and Living Donor Program at the Department of Urology, Loma Linda University School of Medicine. He specializes in endourology, laparoscopy, and robotic surgery. He also directs the research program for the urology residency program.

Dr. Baldwin received his M.D. degree from Loma Linda University School of Medicine in 1991 followed by his urology residency training that he completed in 1997, also at Loma Linda University. He was a member of the United States Air Force and attended the School of Aerospace Medicine in 1988. He was stationed at Andrews Air Force Base for four years from 1997-2001 and was a faculty member at the Uniformed Services University of the Health Sciences. He completed an endourology fellowship in 2002 at Vanderbilt University under Dr. Elspeth McDougal and Dr. Duke Herrell. He returned to Loma Linda University in 2002 and is currently also on staff at Arrowhead Regional Medical Center, Riverside University Health System, the Jerry L. Pettis Memorial Veterans Medical Center, and Highland Springs Surgical Center.

His current research interests are broad and include efforts to reduce the invasiveness of donor nephrectomy, LESS nephrectomy and NOTES surgery. He also has published extensively in the field of urinary stone disease. He is an advocate for reduced radiation exposure to patients and surgeons and he has been invited to present this work at the national and international level.