Ureteroscopy-Assisted Retrograde Nephrostomy

Abstract

Introduction: Lawson et al first developed retrograde nephrostomy in 1983.1 Hunter et al reported 30 cases of retrograde nephrostomy in 1985.2 Ureteroscopy (URS)-assisted retrograde nephrostomy (UARN) was reported as a new technique for percutaneous nephrolithotomy (PCNL) in 2011, and this institute performed more than 30 cases of UARN.3 This video presents the details of the UARN technique based on this experience. Materials and Methods: The patient is placed in the Galdakao-modified Valdivia position under general and epidural anesthesia.4 A ureteral access sheath (UAS) is inserted and a flexible ureteroscope (Flex-X2®; Karl Storz) is inserted through the UAS. The target calculi are carefully observed to identify the appropriate renal calyx to be punctured. A Lawson retrograde nephrostomy puncture wire (Lawson Retrograde Nephrostomy Wire Puncture Set; COOK Urological) is carefully set into the flexible URS. The flexible ureteroscope approaches the desired renal calyx again, and the route from the renal calyx to the exit skin is then confirmed under fluoroscopy. The puncture is performed under ultrasonography after rechecking the preoperative computed tomography to avoid injury to the spleen, liver, intestines, or pleural cavity. The puncture wire passes through the muscle easily and tents the skin at the posterior axillary line. The skin is incised and the needle is delivered. Next, 22G and 18G needle dilators are placed over the puncture wire, which is advanced through the skin, subcutaneous fat, abdominal wall musculature, and perinephric fat until it reaches the renal parenchyma. The catheter is dilated up to 12F and a safety guidewire is placed through the UAS. A 30F percutaneous nephroaccess sheath (NAS; X-Force®N30 Nephrostomy Balloon Dilation Catheter; BARD) is passed over the balloon into the calyx under ureteroscopic and fluoroscopic guidance, and then the balloon is removed. PCNL is then performed. Results: A total of 32 patients were treated by UARN from September 2010 to November 2011. According to this procedure, 81.3% of the patients achieved a stone-free outcome and there were no blood transfusions or any complications in patients with a Clavien score of two or more. The median operation time was 160 minutes. Nephrostomy was therefore not performed on patients who achieved a stone-free outcome, and ureteral stents were put in place at the conclusion of this procedure in all patients.5 UARN was abandoned in one case because of URS mechanical trouble. These patients included two cases of horseshoe kidney, one case of complete staghorn calculi, and two cases of obese patients. Conclusions: UARN is considered to be the most suitable procedure for puncturing the middle calix. UARN is a safe, effective, and minimally invasive procedure for PCNL because continuous observation can be obtained with URS. No competing financial interests exist. Runtime of video: 5 mins 17 secs