Place of non contrast thin-slice spiral computed tomography in evaluation of stone-free ratio after percutaneous nephrolithotomy

A prospective randomized comparison among SWL, PCNL and RIRS for lower calyceal stones less than 2 cm: a multicenter experience : A better understanding on the treatment options for lower pole stones

PURPOSE

To prospectively evaluate the efficacy and safety of RIRS, SWL and PCNL for lower calyceal stones sized 1-2 cm.

MATERIALS AND METHODS

Patients with a single lower calyceal stone with an evidence of a CT diameter between 1 and 2 cm were enrolled in this multicenter, randomized, unblinded, clinical trial study. Patients were randomized into three groups: group A: SWL (194 pts); group B: RIRS (207 pts); group C: PCNL (181 pts). Patients were evaluated with KUB radiography (US for uric acid stones) at day 10 and a CT scan after 3 months. The CONSORT 2010 statement was adhered to where possible. The collected data were analyzed.

RESULTS

The mean stone size was 13.78 mm in group A, 14.82 mm in group B and 15.23 mm in group C (p = 0.34). Group C compared to group B showed longer operative time [72.3 vs. 55.8 min (p = 0.082)], fluoroscopic time [175.6 vs. 31.8 min (p = 0.004)] and hospital stay [3.7 vs. 1.3 days (p = 0.039)]. The overall stone-free rate (SFR) was 61.8% for group A, 82.1% for group B and 87.3% for group C. The re-treatment rate was significantly higher in group A compared to the other two groups, 61.3% (p < 0.05). The auxiliary procedure rate was comparable for groups A and B and lower for group C (p < 0.05). The complication rate was 6.7, 14.5 and 19.3% for groups A, B and C, respectively.

CONCLUSIONS

RIRS and PCNL were more effective than SWL to obtain a better SFR and less auxiliary and re-treatment rate in single lower calyceal stone with a CT diameter between 1 and 2 cm. RIRS compared to PCNL offers the best outcome in terms of procedure length, radiation exposure and hospital stay. ISRCTN 55546280.

Residual stones after percutaneous nephrolithotomy: comparison of intraoperative assessment and postoperative non-contrast computerized tomography

OBJECTIVES

To compare the intraoperative surgeon perspective for detection of residual fragments (RFs) after percutaneous nephrolithotomy (PNL) with postoperative NCCT.

METHODS

A prospective study of adult patients who underwent PNL between March and September 2014 was conducted. Stone complexity was evaluated using the Guy's stone score (GSS). All patients were evaluated by pre- and postoperative NCCT. After the procedure, the surgeon had been asked whether there were residual stones or not. The sensitivity, specificity and predictive values were tested against postoperative NCCT. Predictors of accurate intraoperative assessment were determined using univariate and multivariate statistical analyses.

RESULTS

The study included 306 consecutive patients. The surgeons reported no residual stones in 236 procedures; of whom 170 (72%) were reported stone-free by NCCT. On the other hand, 65 out of 70 procedures (93%) reported with residual stones by the surgeons were true by NCCT. The sensitivity was 50% and the NPV was 72%, while the specificity was 97% and the PPV was 93%. On multivariate analysis, only lower GSS (p < 0.001) was independently associated with true negative surgeon opinion.

CONCLUSIONS

Although there was a high surgeon ability to detect post-PNL residual stones, postoperative imaging is mandatory because of the high false negative rates and low NPV. The surgeon opinions can be judged only in stones with lower GSS. The NPV could be enhanced if a consistent definition of clinically significant RFs is introduced.