Can stone density on plain radiography predict the outcome of extracorporeal shockwave lithotripsy for ureteral stones?

PURPOSE: The objective was to determine whether stone density on plain radiography (kidney-ureter-bladder, KUB) could predict the outcome of extracorporeal shockwave lithotripsy (ESWL) for ureteral stones. MATERIALS AND METHODS: A total of 223 patients treated by ESWL for radio-opaque ureteral stones of 5 to 20 mm were included in this retrospective study. All patients underwent routine blood and urine analyses, plain radiography (KUB), and noncontrast computed tomography (NCCT) before ESWL. Demographic, stone, and radiological characteristics on KUB and NCCT were analyzed. The patients were categorized into two groups: lower-density (LD) group (radiodensity less than or equal to that of the 12th rib, n=163) and higher-density (HD) group (radiodensity greater than that of the 12th rib, n=60). Stone-free status was assessed by KUB every week after ESWL. A successful outcome was defined as stone free within 1 month after ESWL. RESULTS: Mean stone size in the LD group was significantly smaller than that in the HD group (7.5+/-1.4 mm compared with 9.9+/-2.9 mm, p=0.002). The overall success rates in the LD and HD groups were 82.1% and 60.0%, respectively (p=0.007). The mean duration of stone-free status and average number of SWL sessions required for success in the two groups were 21.7 compared with 39.2 days and 1.8 compared with 2.3, respectively (p<0.05). On multivariate logistic analysis, stone size and time to ESWL since colic and radiodensity of the stone on KUB were independent predictors of successful ESWL. CONCLUSIONS: Our data suggest that larger stone size, longer time to ESWL, and ureteral stones with a radiodensity greater than that of the 12th rib may be at a relatively higher risk of ESWL failure 1 month after the procedure.

Predictors of Successful Trial without Catheter for Postoperative Urinary Retention Following Non-Urological Surgery / 대한배뇨장애요실금학회지

PURPOSE: To investigate the success rate of trial without catheter (TWOC) for postoperative urinary retention (POUR) after non-urological surgery and to determine predictors of successful TWOC. METHODS: A total of 104 patients who underwent non-urological surgery and were referred to the department of urology for POUR were included in this retrospective study. All eligible patients underwent indwelling catheterization as an initial treatment and then TWOC was performed 3 to 7 days later. POUR was defined as micturition difficulty with greater than 400 mL of postvoid residual (PVR) urine volume measured by catheterization after non-urological surgery. Successful TWOC was defined as voiding with less than 100 mL of PVR urine volume. Predictive factors were identified by multivariate regression analysis. All definitions corresponded to recommendations of the International Continence Society. RESULTS: The mean age of the patients was 65.2 (range, 23 to 92) years. There were 45 male and 59 female patients. Intraoperative indwelling catheterization was performed in 69 (66.3%) patients. Mean duration of indwelling catheterization for POUR was 5.0 (range, 3.0 to 7.0) days and 83 (79.8%) patients received medication with an alpha-blocker. A successful TWOC was observed in 70 (67.4%) patients. The mean age of the patients with failure of TWOC was significantly higher than that of the patients with successful TWOC. The percentages of female patients, spinal surgery, and prone position during surgery in patients with unsuccessful TWOC were higher than in those with successful TWOC. In the multivariate logistic regression analysis, age and location of surgery (spine vs. non-spine) were the independent predictors of successful TWOC for POUR. CONCLUSIONS: Our data suggest that older age and spinal surgery may be important risk factors for failure of TWOC for POUR after non-urological surgery. Thus, adequate prevention measures may be necessary for POUR after non-urological surgery, especially in patients with these risk factors.