Prospective Multicenter Evaluation of Pain Before and After Removal of Nonobstructing Renal Calculi: A CoRE Initiative.

PURPOSE: Flank pain associated with stone disease is typically caused by a stone that obstructs urine flow. However, it is plausible that nonobstructing kidney stones may still cause pain. We performed a multicenter, observational trial to evaluate whether treatment of small nonobstructing calyceal stones improves pain and kidney stone-specific health-related quality of life. MATERIALS AND METHODS: Patients aged 18 years or older with nonobstructing renal stone(s) up to 10 mm in longest diameter and moderate to severe pain were recruited. All participants completed 3 questionnaires: the Brief Pain Inventory (BPI), the Patient-Reported Outcomes Measurement Information System pain interference form 6a, and the Wisconsin Stone Quality of Life questionnaire. Thereafter, all participants underwent ureteroscopy for renal stone treatment. All 3 questionnaires were repeated at 2, 6 to 8, and at 12 weeks postprocedure. The primary outcomes were change in preoperative to 12-week postoperative mean BPI score and worst BPI pain score. RESULTS: A total of 43 patients with nonobstructing kidney stones and associated flank pain were recruited. All stones were removed. Preoperatively, BPI scores for mean pain and worst pain were 5.5 and 7.2, respectively which decreased to 1.8 and 2.8 respectively at 12 weeks postoperatively. Wisconsin Stone Quality of Life questionnaire mean score increased from 70.4 to 115.3 at 12 weeks postoperatively. A total of 86% and 69% of patients had at least a 20% and 50% reduction in their mean pain scores, respectively. CONCLUSIONS: This study determined that patients benefit significantly from the removal of calyceal nonobstructing kidney stones for at least 12 weeks with a reduction in pain and an increase in quality of life. Therefore, surgical removal of these stones in this patient population should be offered as a treatment option.

Miniaturized percutaneous nephrolithotomy versus retrograde intrarenal surgery in the treatment of renal stones with a diameter <15 mm: A 3-year open-label prospective study.

AIM: The aim of this study is to compare the outcomes of miniaturized percutaneous nephrolithotomy (mini-perc) and retrograde intrarenal surgery (RIRS) in management of renal stones with a diameter <15 mm. MATERIALS AND METHODS: This was an open-label prospective study that included a total of 80 cases underwent mini-perc (n = 40) and RIRS (n = 40) between July 2014 and August 2017. The primary outcome objective was stone-free rate, retreatment rate, complications, hospital stay, operative time, and reduction in hemoglobin level. Data were analyzed using SPSS version 16.0 Software. RESULTS: Overall, 80 patients were enrolled in this study. The mean age was 40.12 and 38.20 years, and the mean stone size was 1.15 and 1.30 cm in mini-perc and RIRS group, respectively. Majority of the study participants were males. Overall, mini-perc and RIRS had stone clearance rates of 100% and 95.4%, respectively. Two patients required retreatment in RIRS group. The duration of hospital stay and the rate of complication was similar in both the groups. Operative duration was more in RIRS group. Decrease in hemoglobin level was more in mini-perc group. CONCLUSIONS: Results demonstrated that both modalities were associated with high stone clearance rates with minimal complications. RIRS was associated with less reduction in hemoglobin and could be used as standard treatment modality for small renal calculi.

Current role of microperc in the management of small renal calculi.

'Microperc' is a recently described technique in which percutaneous renal access and lithotripsy are performed in a single step using a 16 G micropuncture needle. 'Mini-microperc' is a further technical modification in which an 8 Fr sheath is used to allow insertion of ultrasonic or pneumatic lithoclast probe with suction. The available evidence indicates that microperc is safe and efficient in the management of small renal calculi in adult and pediatric population. It can also be used for renal calculi in ectopic kidneys and bladder calculi. The high stone clearance rate and lower complication rate associated with microperc make it a viable alternative to retrograde intrarenal surgery.

Micropercutaneous nephrolithotomy (microperc) vs retrograde intrarenal surgery for the management of small renal calculi: a randomized controlled trial.

OBJECTIVE: To compare micropercutaneous nephrolithotomy (microperc) and retrograde intrarenal surgery (RIRS) for the management of renal calculi <1.5 cm with regard to stone clearance rates and surgical characteristics, complications and postoperative recovery. PATIENTS AND METHODS: Seventy patients presenting with renal calculi <1.5 cm were equally randomized to a microperc or a RIRS group between February 2011 and August 2012 in this randomized controlled trial. Randomization was based on centralized computer-generated numbers. Patients and authors assessing the outcomes were not blinded to the procedure. Microperc was performed using a 4.85-F (16-gauge) needle with a 272-µm laser fibre. RIRS was performed using a uretero-renoscope. Variables studied were stone clearance rates, operating time, need for JJ stenting, intra-operative and postoperative complications (according to the Clavien-Dindo classification system), surgeon discomfort score, postoperative pain score, analgesic requirement and hospital stay. Stone clearance was assessed using ultrasonography and X-ray plain abdominal film of kidney, ureter and bladder at 3 months. RESULTS: There were 35 patients in each group. All the patients were included in the final analysis. The stone clearance rates in the microperc and RIRS groups were similar (97.1 vs 94.1%, P = 1.0). The mean [sd] operating time was similar between the groups (51.6 [18.5] vs 47.1 [17.5], P = 0.295). JJ stenting was required in a lower proportion of patients in the microperc group (20 vs 62.8%, P < 0.001). Intra-operative complications were a minor pelvic perforation in one patient and transient haematuria in two patients, all in the microperc group. One patient in each group required conversion to miniperc. One patient in the microperc group needed RIRS for small residual calculi 1 day after surgery. The decrease in haemoglobin was greater in the microperc group (0.96 vs 0.56 g/dL, P < 0.001). The incidence of postoperative fever (Clavien I) was similar in the two groups (8.6 vs 11.4%, P = 1.0). None of the patients in the study required blood transfusion. The mean [sd] postoperative pain score at 24 h was slightly higher in the microperc group (1.9 [1.2] vs 1.6 [0.8], P = 0.045). The mean [sd] analgesic requirement was higher in the microperc group (90 [72] vs 40 [41] mg tramadol, P < 0.001). The mean [sd] hospital stay was similar in the two groups (57 [22] vs 48 [18] h, P = 0.08). CONCLUSIONS: Microperc is a safe and effective alternative to RIRS for the management of small renal calculi and has similar stone clearance and complication rates when compared to RIRS. Microperc is associated with higher haemoglobin loss, increased pain and higher analgesic requirements, while RIRS is associated with a higher requirement for JJ stenting.