LAUSR

INTRODUCTION Ureteroscopy has been shown to be a highly efficacious and safe modality for the treatment of pediatric urolithiasis. However, conventional ureteroscopy relies on fluoroscopy for intraoperative guidance, exposing both patient and operating room personnel to ionizing radiation. Pediatric urolithiasis patients are at a particularly increased risk from this radiation exposure. The use of ultrasound in place of fluoroscopy for intraoperative guidance has emerged as one modification that can reduce radiation exposure during ureteroscopy. Although ultrasound-guided ureteroscopy has been shown to be a safe, and effective approach to stone management in adults, there have been no studies to date utilizing this approach in children. OBJECTIVE The aim was to describe our initial experience with ultrasound-guided ureteroscopy in children as a safe and feasible modality to manage pediatric urolithiasis. STUDY DESIGN A retrospective review of consecutive patients that underwent ultrasound-guided ureteroscopy by one pediatric urologist (A.K.S.) from 2014 to 2016 for symptomatic urolithiasis was performed. Patient data were extracted from our center's IRB-approved prospectively maintained database of all children with urolithiasis. MATERIALS AND METHODS Real-time ultrasonic guidance was provided by a pediatric uroradiology attending, with fluoroscopy available on standby. With the probe positioned on the patient's flank, ultrasound was used to visualize advancement of guidewire, dual-lumen catheter, and ureteroscope through the ureteral orifice and up to the renal pelvis (Figure). Stones were identified and removed via basket retrieval. At the conclusion of each case, ultrasonography was then used to confirm stent placement of indwelling double pigtail ureteral catheters. RESULTS Eleven patients were identified that underwent 12 ultrasound-guided ureteroscopic procedures in an outpatient setting. Stones were accessed in various locations and were removed by basket retrieval. Laser calycostomy into calyceal diverticulum and balloon dilations of ureterovesical junction and calyceal infundibulum were also performed. There were Clavien grade I and II complications in four patients; all of which were related to pain control. DISCUSSION To our knowledge, this is the first study reporting the successful use of ultrasound-guided ureteroscopy in children. The main limitation of this feasibility study is its small sample size. A larger series is needed to corroborate these findings and make them generalizable to a wider population. CONCLUSION This feasibility study accomplished its aim of demonstrating for the first time that ultrasound-guided ureteroscopy can be safely used in children to manage urolithiasis.