Seung Choul Yang

What are ‘true normal’ liver stiffness values using FibroScan®?: a prospective study in healthy living liver and kidney donors in South Korea

Aims: To identify the normal range of liver stiffness (LS) values by recruiting healthy living liver and kidney donors in South Korea.

Comparison of single and multiple sessions of percutaneous sclerotherapy for simple renal cyst: PERCUTANEOUS SCLEROTHERAPY

Objective To compare the results of single and repeated percutaneous sclerotherapy in patients with simple renal cysts.

Predictors of Kidney Volume Change and Delayed Kidney Function Recovery After Donor Nephrectomy

PURPOSE To our knowledge the effects of preoperative kidney volume in living donors on the post-donation change in size and function of the remaining kidney have not been investigated. We studied the association between preoperative kidney volume, and volume change and delayed kidney function recovery in donors. MATERIALS AND METHODS From 2007 to 2008 we investigated 222 living donors. Kidney volume before and 6 months after surgery was estimated using the voxel count method. We analyzed correlations of kidney volume with patient characteristics, kidney function and actual kidney weight. To identify predictors of the volume increase of the remaining kidney and predictors of delayed kidney function recovery we performed regression analysis. RESULTS Mean +/- SD total kidney volume was 311.9 +/- 50.6 cc and it correlated with weight, body surface area and kidney function (p <0.001). The mean volume increase in the remaining kidney was 27.6% +/- 9.7% (range 4.5% to 66.1%). Younger age (p <0.001) and lower preoperative volume of the remaining kidney (p = 0.019) were significant predictors of a greater increase in kidney volume on multiple linear regression analysis. Older age (OR 1.07, p <0.001), higher body mass index (OR 1.20, p = 0.008), lower preoperative kidney volume of the remaining kidney (OR 0.98, p = 0.003) and a lower preoperative diethylenetetramine pentaacetic acid glomerular filtration rate in the remaining kidney (OR 0.95, p = 0.017) were significant predictors of delayed kidney function recovery on multiple regression analysis. CONCLUSIONS Kidney volume measured by the voxel count method was accurate and correlated with kidney function. Preoperative kidney volume is an independent predictor of the volume increase and delayed kidney function recovery in donors that could be used clinically.

Laparoendoscopic Single-Site Surgeries: A Single-Center Experience of 171 Consecutive Cases

Purpose We report our experience to date with 171 patients who underwent laparoendoscopic single-site surgery for diverse urologic diseases in a single institution. Materials and Methods Between December 2008 and August 2010, we performed 171 consecutive laparoendoscopic single-site surgeries. These included simple nephrectomy (n=18; robotic surgeries, n=1), radical nephrectomy (n=26; robotic surgeries, n=2), partial nephrectomy (n=59; robotic surgeries, n=56), nephroureterectomy (n=20; robotic surgeries, n=12), pyeloplasty (n=4), renal cyst decortications (n=22), adrenalectomy (n=4; robotic surgeries, n=2), ureterolithotomy (n=10), partial cystectomy (n=3), ureterectomy (n=1), urachal mass excision (n=1), orchiectomy (n=1), seminal vesiculectomy (n=1), and retroperitoneal mass excision (n=1). All procedures were performed by use of a homemade single-port device with a wound retractor and surgical gloves. A prospective study was performed to evaluate outcomes in 171 cases. Results Of the 171 patients, 98 underwent conventional laparoendoscopic single-site surgery and 73 underwent robotic laparoendoscopic single-site surgery. Mean patient age was 53 years, mean operative time was 190.8 minutes, and mean estimated blood loss was 204 ml. Intraoperative complications occurred in seven cases (4.1%), and postoperative complications in nine cases (5.3%). There were no complications classified as Grade IIIb or higher (Clavien-Dindo classification for surgical complications). Conversion to mini-incision open surgery occurred in seven (4.1%) cases. Regarding oncologic outcomes, no cancer-related events occurred during follow-up other than one aggressive progression of Ewing sarcoma. Conclusions Laparoendoscopic single-site surgery is technically feasible and safe for various urologic diseases; however, surgical experience and long-term follow-up are needed to test the superiority of laparoendoscopic single-site surgery.

RETROPERITONEAL ENDOSCOPIC LIVE DONOR NEPHRECTOMY: REPORT OF 3 CASES

In a variation of laparoscopic surgery we performed retroperitoneal surgery using endoscopy and a special retractor in 3 cases of live donor nephrectomy. The procedure using retroperitoneal endoscopy offers several advantages compared to conventional live donor nephrectomy. With the development of retractors to obtain operating space and the further development of surgical techniques retroperitoneal endoscopic live donor nephrectomy can be established as an alternative surgical method for harvesting donated kidneys.

Normal liver elasticity values using acoustic radiation force impulse imaging: A prospective study in healthy living liver and kidney donors

Background and Aim:  Although several studies have investigated the normal range of liver elasticity using acoustic radiation force impulse (ARFI) elastography in healthy volunteers, they could not strictly exclude the morphological and functional liver abnormalities. The aim of this study was to identify the normal range of ARFI velocity by recruiting healthy living liver and kidney donors who passed the full laboratory tests and imaging studies.

Benign Lesions After Partial Nephrectomy for Presumed Renal Cell Carcinoma in Masses 4 cm or Less: Prevalence and Predictors in Korean Patients

OBJECTIVES To investigate the prevalence and predictors associated with benign lesions in Korean patients after partial nephrectomy for presumed renal cell carcinoma (RCC) for lesions measuring ≤ 4 cm. METHODS We retrospectively investigated the medical records of 376 patients who underwent partial nephrectomy for presumed RCC with renal masses of size ≤ 4 cm between June 1997 and December 2008. Demographic and clinicopathologic parameters were compared between benign lesions and RCC. Logistic regression was done to identify parameters associated with benign lesions. RESULTS In the 376 patients, 81 tumors (21.5%) were benign, including 35 angiomyolipomas (9.3%), 26 complicated cysts (6.9%), 11 oncocytomas (2.9%), and 9 others (2.4%). Univariate analysis showed that time of surgery, female sex, younger age, and normal body mass index (body mass index (BMI) < 23 kg/m(2)) were associated with benign pathologic findings. On multiple logistic regression analysis, female sex (OR, 4.91; 95% CI, 2.76-08.75; P < .001), age (OR, 0.97; 95% CI, 0.95-0.99; P = .009), and time of surgery (OR, 0.33; 95% CI, 0.11-0.95; P = .040) were independent predictors of benign histologic features. Tumor size, incidental diagnosis, and BMI were not significant predictors (P > .05). CONCLUSIONS Our study with a large cohort of Asian patients showed that the prevalence of benign lesions was similar to previously reported Western studies. However, the most common benign lesion was angiomyolipoma, compared with oncocytoma in Western countries. The results of this study may help clinicians counsel female and younger patients recently diagnosed with small renal masses and decide the most appropriate treatment, including renal biopsies and close observation.

RETROPERITONEOSCOPY ASSISTED LIVE DONOR NEPHRECTOMY: THE YONSEI EXPERIENCE

PURPOSE Retroperitoneoscopy assisted live donor nephrectomy has become standard based on our experience with 103 consecutive cases operated on between January 1993 and May 2000. We describe the advantages of retroperitoneoscopy assisted compared to laparoscopic live donor nephrectomy. MATERIALS AND METHODS After performing more than 1,200 cases of open live donor nephrectomy (S. C. Y.), we combined our experience with open and laparoscopic surgery to develop a specific technique of minilaparotomy live donor nephrectomy. Operations were performed by 1 senior surgeon and 1 assistant, with the help of specially designed piercing abdominal and peritoneal retractors. A 5 to 7 cm. transverse pararectal skin incision is made at the level of 10th rib and the abdominal muscles are split without division. A 10 mm. port is placed at the lower abdomen to allow for the telescope. The procedure is performed extraperitoneally, combining open and laparoscopic instruments under direct vision. Renal pedicles and ureters are ligated using laparoscopic clips and sutures. The kidney is removed via laparotomy and the wound is closed. RESULTS Average operating time for the 103 live donor nephrectomies was 130 minutes (range 85 to 210), and there was no case of kidney loss, open surgical conversion or blood transfusion. Mean warm ischemia time was 2.3 +/- 1.2 minutes and average incision length was 6.5 cm. (range 5.1 to 7.0). Postoperative pain was minimal and analgesics were generally not required by postoperative day 2. Patients were fully ambulatory a mean 1.5 days (range 1 to 3.5) postoperatively. CONCLUSIONS Retroperitoneoscopy assisted live donor nephrectomy is not only feasible, but reproducible. Any surgeon with previous experience with conventional open live donor nephrectomy can perform this hybrid, minimally invasive procedure.

The Risk Factor for Urethral Recurrence after Radical Cystectomy in Patients with Transitional Cell Carcinoma of the Bladder

Purpose: We evaluated the incidence and risk factors for urethral recurrence following radical cystectomy and urinary diversion in transitional cell carcinoma. Patients and Methods: A retrospective review was performed of the 412 consecutive patients who underwent radical cystectomy and urinary diversion for transitional cell carcinoma of the bladder between 1986 and 2004. A total of 294 patients were enrolled in this study. We investigated the impact of various clinical and pathological features on urethral recurrence by univariate and multivariate analysis. Results: Urethral recurrence developed in 13 patients (4.4%) and the 5-year urethral recurrence-free probability was 94.9%. On univariate analysis, positive urethral margin, prostatic stromal invasion, and prostatic urethral involvement had a significant influence on urethral recurrence (p < 0.05). The other clinical and pathological features were not significantly associated with urethral recurrence (p > 0.05). A multivariate Cox proportional hazard model revealed that a positive urethral margin (hazards ratio (HR) = 18.33, p < 0.001), prostatic urethral involvement (HR = 7.95, p < 0.001), and prostatic stromal invasion (HR = 5.80, p = 0.018) were independent risk factors for urethral recurrence. Conclusion: A positive urethral margin is considered an absolute indication for prophylactic urethrectomy. In addition, more careful patient selection is necessary for orthotopic urinary diversion in patients with prostatic urethral involvement and prostatic stromal invasion.

Transutricular Seminal Vesiculoscopy

Disorders of the seminal vesicle have been evaluated mainly via imaging techniques. We developed a technique to examine the interior of seminal vesicles endoscopically. In 37 hemospermic patients, transrectal ultrasound (TRUS) or endorectal MRI were performed preoperatively. When the patients had definite abnormalities on the imaging studies and did not improve after medication over a period exceeding 3 months, transutricular seminal vesiculoscopy was performed using a 6F or a 9F rigid ureteroscope. Patients were then followed for at least 3 months. Endoscopic evaluation was also performed in two patients with stage B(1) and D(2) prostate carcinoma. In hemospermic patients, hemorrhage was found in the seminal vesicles or the ejaculatory ducts in 23 (62.2%) and 3 (8.1%), respectively. Calculi were present in the seminal vesicles or ejaculatory ducts in 6 (16.2%) and 2 (5.4%), respectively. In prostate carcinoma patients, seminal vesiculoscopy was similarly informative. Postoperative complications, including epididymitis or retrograde ejaculation, were not observed. Transutricular seminal vesiculoscopy can be performed easily with conventional endoscopic equipment and provides useful information.