Department of Urology: School of Medicine: University of California, Irvine


The Department of Urology has a driving interest in studying prostate cancer, bladder cancer, tissue bioengineering, surgical training through simulation, and new methods of less invasive and robotic surgery.

Ureteropelvic junction obstruction (UPJO) is the most common congenital anomaly of the ureter. A dismembered pyeloplasty represents the gold standard treatment, which can be performed using minimally invasive techniques such as keyhole laparoscopic surgery or robotic surgery.

The Urologic Surgeons at the University of California Irvine have adopted the use of robotic surgery for the repair of UPJO. In a study lead by Dr. Etafy, with the supervision of Dr. Michael Louie and Dr. Elspeth McDougall, our results on the use of the robot for the repair of UPJO will be published in the Journal of Urology June 2011 Issue. The table below is a summary of our results and a comparison of the published literature for robotic pyeloplasty.

We wish to highlight in this table that our definition of success was the most stringent published in the recent literature. Our criteria for overall success required both subjective (pain score) and objective (diuretic renal scan) success. We found this decreased our primary success rate, but we believe that the traditionally quoted success rate of 95% or better may be overstated depending on the criteria for “success”. If we defined success as either an improvement in pain or in diuretic renal scan t ½ clearance time, then our success rate would increase to 93%.

The complication rate is 12.3% which is slightly higher than most reported series, however we used the complication classification system by Clavian classification which includes lower morbidity complications. If we considered only significant complication (as outlined in other studies) ,our major complication rate will be 5%.

Further multi-center study with a standard follow up protocol that includes subjective and objective definitions of success should be performed in order to more accurately counsel patients about the surgical options for treatment of ureteropelvic junction obstruction.


Comparison of Literature on the Robotic Pyeloplasty for UPJO

Authors / Institution NO. of patients Mean age (years)
Mean OT (min)
Mean EBL (ml)
Mean LOS (days) Mean FU (months)
CR (%) Primary SR (%) Definition of success
Etafy / UCI 57 35 (19–51) 335 (247–423) 61 (13- 109) 2 (1.1-2.9) 18 (3-33) 12.3 81  Pain score < 2 & t1/2 <10
Yanke /
Thomas Jefferson University PA
18 41.2 (17/82) 196 (120–420) 39 (25–150) 2.2 (NS) 11 (6–17) 11.1 100 Subjective improvement in pain & renogram
Siddiq  /
University of Miami
26 34.5 (17–62) 245 (165–390) 69 (25–200) 2.0 (1–5) 6 (2–10) 11.5 95 t1/2<15 & improvement in pain
Weise  /
University of Iowa
31 36.3 (19–47) 299 (181–435) <100 (NS) 2.0 (1–4) 10 (1–21) 6.4 97 No significant obstruction on renogrem
Bernie /
Indiana University
7 32 (25–49) 324 (252–420) 60 (50–100) 2.5 (2–6) 10 (5–15) 6.2 100 Pain score < 2& improvement in  renogram
Palese /
Mount Sinai medical center
35 39 (15–69) 216 (161–280) 74 (22–130) 3.8 (1–13) 7.9 (2–11) 0 94 Subjective improvement in pain & renogram
Patel /
Urology center of Alabama
50 31 (16–62) 122 (60–330) 40 (25–100) 1.1 (NS) 12 (1–28) 2 96 NS
Medical university
Innsbruck Austeria
92 35 (14–74) 108 (72–215) NS 4.5 (3–11) 39 (3–73) 3 97 improvement in pain & U/S
Mufarrij / (three centers) 140 38.5 (7–79) 217 (80–510) 59 (10–600) 2.1 (0.75–7) 29 (3–63) 10 95.7 First renogram
t 1/2 <20
Or prompt nephrogram

CR = Complication rate, EBL = Estimated blood loss, FU = Follow up, LOS = length of hospital stay, NO = Number, OT = Operative time, RT = Robotic pyeloplasty, SR = Success rate, UCI = university of California Irvine, UPJ = ureteropelvic junction, UPJO = ureteropelvic junction obstruction




Dr. Ralph Clayman and his colleagues are world renowned for their expertise as surgeons and researchers in the use of minimally invasive surgery for kidney and other urological diseases. Their research has resulted in more than 500 peer-reviewed papers and book chapters. They also are asked to consult with surgeons worldwide on minimally invasive techniques and are recognized as leaders in providing educational courses on these techniques to other urologists nationwide.

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Patients benefit from these research findings with less-invasive surgeries, less blood loss and reduced recovery times. Their findings, which have been adapted to the operating room and bedside, include:

  • Expanding the use of laparoscopic minimally invasive surgery for a number of disorders, including kidney removal for benign disease and for cancer, correction of urinary tract obstruction, and application of laparoscopy to various aspects of pediatric urology.
  • Discovering a close relationship between urinary incontinence and attention deficit/hyperactivity disorder. These findings could help reverse this urinary disorder with special treatment for children with ADHD.
  • Using newly developed technology (often first tested in the UC Irvine urology laboratory) for better endoscopic treatment of patients with kidney and ureteral stones.
  • Under the guidance of Dr. Xiaolin Zi, the department has secured more than $2.5 million in peer-review research funding.