Congenital hydronephrosis is the most common kidney malformation, mostly in boys, and almost always occurs during fetal life. The main cause is the narrowing of the junction between the renal pelvis and the ureter, and the accumulation of urine in the kidney, leading to the development of “hydrocele”. A fetus can produce urine from 4 months of age, and hydronephrosis is likely to be more than 5 months old at birth. If left untreated, the fluid is likely to lead to infection and stones, which can affect kidney function. The only cure for this condition is surgical removal of the stenotic segment followed by reshaping of the pelvic ureter. Traditional surgery requires more drains to be left in place or even drainage from the nephrostomy, which is more invasive and has more complications. It is no longer the main measure for the treatment of this disease. Minimally invasive surgery using lumpectomy can be done with minimal trauma and almost no scarring of the abdominal wall, and current studies show that minimally invasive surgery is better than traditional open surgery in all aspects, and can significantly shorten hospital stays and reduce treatment costs. What is “pneumoperitoneoscopy”? What are the benefits? Pneumoperitoneoscopy is a technique that uses an advanced pediatric laparoscopic system to create a surgical space inside the bladder using carbon dioxide and to perform surgical operations. Traditional bladder surgery involves opening the abdomen and bladder, which results in large wounds, a time-consuming operation, and a slow post-operative recovery. Pneumatic bladder surgery is minimally invasive, no sutures or stitches are required, and it is particularly suitable for infants and children because of its mild pain and quick recovery.