LAUSR

Objective To report our experience of hydro-dissection ultrasonography (US)-guided percutaneous nephrolithotomy (HU-PCNL) used to facilitate entry to the pelvi-calyceal system (PCS) and optical HU-PCNL (OHU-PCNL) to visualise tissue layers during PCS entry. Both HU-PCNL and OHU-PCNL are used for difficult cases of renal stones that are not candidates for classical PCNL by use of US guidance, e.g. in obese patients, horseshoe kidney, ectopic pelvic kidney, transplanted kidney, and lower calyx stones covered by colon; and used in ectopic pelvic kidney PCNL to avoid abdominal organs injury. OHU-PCNL visualises the stone directly at the moment of entry to the PCS then passes the infundibulum, enters the pelvis, and allows selection of the optimum side for guidewire insertion. OHU-PCNL avoids colonic injury and if the needle perforates the colon it can be seen allowing removal of the needle and a change in direction. Methods Between January 2016 to October 2017, 30 patients underwent HU-PCNL with a mean (range) age of 36.4 (3–67) years (13 female, 17 male). Two patients had horseshoe kidneys, one patient had a transplanted kidney, one patient had a single kidney, and two patients had malrotated kidneys. In all, seven patients underwent OHU-PCNL with a mean (range) age of 39.7 (30–50) years (three female, four male), one patient had a left ectopic pelvic kidney. Results Five patients had renal stones (stone size 15–40 mm), one of which had a left ectopic pelvic kidney. The mean operation time was 90 min, four patients were in prone position and one in supine position due to an ectopic pelvic kidney, the mean age was 39.2 years. In four males and one female, the mean (range) operation time was 94 (60–180) min), and there were no abdominal organs injury or blood transfusions. The patients were admitted for only 1 day, except for the patient with the pelvic ectopic kidney who was admitted for 3 days. Conclusion OHU-PCNL is a safe novel method used in difficult cases of renal stones, especially in ectopic pelvic kidneys to prevent and allow early diagnosis of bowel injury. OHU-PCNL can avoid colonic injury and allow tangential entrance to the PCS.