Laparoscopic and Robot-assisted Laparoscopic Reimplantation for Lower Ureter Pathology. A Multi-institutional Comparative Study in 1343 Patients.

OBJECTIVE: To evaluate the outcomes of children with vesicoureteral reflux (VUR) and obstructive megaureter (OM) utilizing various laparoscopic and robot-assisted approaches. MATERIALS AND METHODS: Retrospective review of all pediatric laparoscopic and robot-assisted cases for lower ureter pathology was performed between 2016-2022 in 13 academic centers worldwide. Five surgical approaches were assessed: LEUR, LVCUR, LDECUR, RALUR, and RADECUR. RESULTS: One thousand three hundred forty-three patients (490 boys and 853 girls) with a median age of 30 months (IQR 12-63) were treated at 13 centers. Nine hundred and eight patients (68%) underwent reimplantation due to VUR (unilateral in 818 and bilateral in 90 patients). Four hundred thirty-five (32%) had a surgery due to ureterovesical junction (UVJ) obstruction. Mean length of follow-up was 14 months (IQR 8-33). Median operative time was 202 minutes (IQR 142-220) in the robotic arm compared to 240 minutes (IQR 160-267) in the laparoscopic (P = .45). Intracorporeal excisional tapering was performed in 118 (8%) of the patients. Six patients in the OM group required additional surgery due to progressive obstruction. In the VUR group, 84% underwent voiding cystourethrography postoperatively. 5.6% showed residual reflux. Grade 1-2 Clavien-Dindo complications occurred in 10 patients (0.7%) and 6 (0.4%) in the laparoscopic and robotic arm, respectively. Grade 3 complications occurred in 17 (1.2%) and 8 (0.5%) in both arms, respectively. Surgical success was achieved in 96% of patients. CONCLUSION: Laparoscopic and robot-assisted laparoscopic approaches are simple, safe, and effective for treating all grades of VUR and OM. Robot-assisted approach is beneficial in terms of operative time, intracorporeal suturing, and lower complications rate.

Effect of copper oxide on the structure of nano-sized Ni(x)Zn(y)Fe2O4 powders prepared by using self-propagating high temperature synthesis.

Nano-sized Cu(x)Ni(x)Zn(1-x-y)Fe2O4 ferrites were prepared by using self-propagating high-temperature synthesis (SHS) and mechanical ball milling. As oxygen pressure increases and copper content decreases in the initial composition, average combustion temperature and combustion velocity increases in the ranges of 947 to 1150 degrees C and 4.2 to 6.5 mm/sec, respectively. The SHS products were agglomerated crystalline powders in which fine particles were present. The average particle of the pulverized SHS product was about 200 nm. Lattice parameters determined by neutron diffractometry are 8.4125 angstroms for Ni0.38Zn0.62Fe2O4 and a = 8.3540 angstroms for Cu0.29Ni0.28Zn0.43Fe2O4.