S. Dominique

A 970 Hounsfield units (HU) threshold of kidney stone density on non-contrast computed tomography (NCCT) improves patients' selection for extracorporeal shockwave lithotripsy (ESWL): evidence from a prospective study.

Study Type – Therapy (prospective cohort)

The Learning Curve of Transrectal Ultrasound-guided Prostate Biopsies: Implications for Training Programs

OBJECTIVE To assess the quality of specimens obtained from prostate biopsies performed by urology residents and evaluate the number of procedures required to perform high-quality transrectal ultrasound (TRUS)-guided prostate biopsies. MATERIALS AND METHODS Between 2006 and 2009, 770 patients underwent TRUS-guided prostate biopsies in our academic center. During the 6 semesters of this period, 24 residents (4 per semester) performed 1 session of 5.6±1.5 procedures each month for a total of 33.6±9 procedures during the study. The first session was performed with a senior urologist. Prostate cancer detection rate and standards of quality (average length of prostatic core biopsy specimens and absence of prostatic tissue) were retrospectively studied between the beginning and the end of each semester. RESULTS A total of 12,760 biopsy cores were performed for 770 procedures. Mean patient age (64.5±6.1 years), and median prostate-specific antigen (8.7±3.7 ng/mL) were comparable between the study periods. The average length of biopsy cores significantly improved (+10%) from the first (12±2.7 mm) to the last month (13.2±2.1 mm) with a plateau after 12 procedures. Overall, cancer detection rate was 47% and was stable during the semester (41.3% the first month vs 44.1% the last month; P=.39). On univariate and multivariate analysis the mean length of biopsy specimens was associated with the number of procedures (P<.001) and the number of cores performed (P<.001). CONCLUSION Twelve procedures are necessary to perform high-quality TRUS-guided prostate biopsies without compromising prostate cancer detection. In current training programs, we strongly recommend that residents have direct supervision for a minimum of 12 cases before they are allowed to perform TRUS-guided biopsies with indirect supervision.

Double J stent reduces the efficacy of extracorporeal shock wave lithotripsy in the treatment of lumbar ureteral stones

Introduction We evaluated the effect of the presence of a double J stent on the efficacy of extracorporeal shock wave lithotripsy (ESWL) in the treatment of lumbar ureteral stones. Material and methods Between January 2007 and February 2012, we performed a retrospective cohort study. Forty–four patients were treated by ESWL for lumbar ureteral stones and included into two groups for the analysis: group 1, non–stented (n = 27) and group 2, stented patients (n = 17). Treatment efficacy was evaluated by abdominal X–ray or CT–scan at 1 month. Stone–free patients and those with a residual stone ≤4 mm were considered to be cured. Results Mean stone size and density in groups 1 and 2 were 8.2mm/831HU, and 9.7 mm/986HU respectively. Both groups were comparable for age, BMI, stone size and density, number, and power of ESWL shots given. The success rates in groups 1 and 2 where 81.5% and 47.1%, respectively (p = 0.017). There was no difference between the groups for stones measuring 8 mm or less (p = 0.574). For stones >8 mm, the success rates were respectively 76% and 22.2% for groups 1 and 2 (p = 0.030). Logistic regression analysis revealed a higher failure rate when a double J stent was associated with a stone >8 mm (p = 0.033). Conclusions The presence of a double J stent affects the efficacy of ESWL in the treatment of lumbar ureteral stones. This effect is significant for stones >8 mm. Ureteroscopy should be considered as the first–line treatment in such patients.