For ureteral injuries, reconstruction with one’s own urinary tract tissue is the preferred clinical option. However, if the length of the ureteral defect cannot be replaced by its own urinary tract tissue, ileal substitution ureterotomy is an alternative and effective treatment. It can maintain the continuity of the urinary tract and preserve and improve renal function. However, there are strict indications and contraindications for ileal substitution ureterotomy, and the surgical technique is difficult, so it is rarely performed in China. Therefore, this article summarizes a case of ileal substitution ureterotomy for the treatment of a patient with long segmental ureteral defect and reviews the relevant literature in order to provide reference and guidance for clinical work. I. MEDICAL HISTORY: The patient was a 53-year-old male who presented to a local hospital with “left low back pain for six months”. Ultrasound and intravenous urography showed bilateral kidney stones, left ureteral stones and left hydronephrosis. In May 2010, she underwent pneumatic ballistic lithotripsy via left ureteroscopy in an outside hospital, during which the ureter was damaged and the stone was not removed. After the operation, she had fever and left hydronephrosis for a short period of time. Under local anesthesia, left percutaneous nephrolithotomy was performed. The left ureteral orifice was not found by cystoscopy 2 weeks after the operation. Second, auxiliary examination: preoperative abdominal plain film and left nephrostomy tube contrast showed: stones were visible in both renal regions, left renal pelvis was dilated, and the upper part of the left ureter was atretic. Urologic CT enhancement examination: multiple irregular stones of different sizes were seen in both renal pelvis and calyces, the largest one was located in the right renal pelvis with a size of 11mm×8mm, and another one was seen in the upper part of the left ureter with a class of round stones with a diameter of about 8mm. the left renal pelvis and upper part of left ureter were dilated, and fistulae could be seen in the left renal pelvis. The middle and lower part of the left ureter and the upper part of the ureter below the third lumbar vertebrae were striated, and the lumen disappeared. Renal dynamic examination showed that the left kidney had reduced perfusion and impaired function, the left upper urinary tract drainage was not poor (open nephrostomy tube), the right kidney had normal perfusion and function, and the right upper urinary tract drainage was poor.GFR: 28ml/min on the left side, 40ml/min on the right side. Cystoscopy under anesthesia: scarring was seen in the vicinity of the left ureter, and the left ureteral orifice was not found. The patient had a ureteral injury caused by pneumatic ballistic lithotripsy for left ureteral stone. Combined with preoperative pyelogram and urologic CT examination, the length of the ureteral defect was estimated to be about 20 cm, which was a long ureteral defect. Ureterocystocele reanastomosis and ureterocystocele flap anastomosis (Boari procedure) were not suitable. Surgical options that can be considered are long-term nephrostomy, autologous kidney transplantation, ileocecal substitution ureterotomy, and nephrectomy. Long-term nephrostomy increases the risk of infection, requires regular replacement of the fistula, and affects the patient’s quality of life. Nephrectomy of the affected side does not save the corresponding renal function, and the patient refused to undergo nephrectomy. The patient refused to undergo nephrectomy. After ureteral injury, inflammatory adhesions were caused by extravasation of urine from the left perirenal area, which made it difficult to obtain a donor kidney for autologous renal transplantation, and the length of the ureter for cystocele anastomosis was relatively short. After comprehensive consideration, the decision was made to perform ileal substitution ureteral surgery. Surgical method: A median incision was chosen to enter the abdomen, and the left paracolic groove was opened. After touching the ureteral stone, the ureter was freed to reveal the severe adhesion and remove the ureteral stone. The ureter was completely atretic at the distal end of the stone. The length of the damaged ureteral segment was measured to be about 20 cm. 25 cm of the ileal segment was cut, and the mesentery of the ileal segment was preserved. A window was opened in the descending mesentery, and the ileal segment was pulled through the window into the retroperitoneal space, closing the mesenteric fissure, taking care to avoid stenosis and to ensure that the ileal segment was oriented in a peristaltic direction from top to bottom. The bowel segment reaches the ureteral dissection superiorly and the pelvis inferiorly, avoiding excessive mesenteric tension. The proximal ureter is cut obliquely and anastomosed to the ileocecal segment. The left posterior wall of the bladder is opened and the whole bladder is anastomosed intermittently to the severed end of the bowel, after which the second layer is sutured intermittently with a slight trocar, and the anti-reflux ileocecal papillary structures are not done because the patient is a patient with renal calculi. The mesenteric and retroperitoneal gap was closed and the intestinal collaterals were placed behind the descending colon. V. Postoperative management: Soft cystoscopic observation and removal of the left double J-tube 4 weeks after surgery. The right double J-tube was left in place at the same time because the right kidney stone was obstructing the right ureter. The left nephrostomy tube imaging was performed 45 days after the operation, which showed that the left ileum substituted for the ureter was patent, there was no stenosis in the anastomosis, and the left hydronephrosis was significantly improved. The left nephrostomy tube was removed. ESWL for right renal stone was performed in February after surgery, and the right D-J tube was removed. Intravenous urography was performed in 2 months after surgery, which showed disappearance of stone shadow in both renal regions, no hydronephrosis bilaterally, and patency of the left ileocecal substitute ureter. Vesicoureteral refluxography on 65 days after surgery showed mild reflux of contrast medium into the lower end of the left ileocecal substitute ureter during bladder filling and urination, without entering the renal pelvis. Renal dynamics were reviewed 3 months postoperatively: left renal GFR 39 ml/min, right renal GFR 41 ml/min. bilateral upper urinary tract drainage was patent. DISCUSSION I. OVERVIEW In 2007, the first case of ileal substitution ureteral surgery was reported by Shoemaker for the treatment of female patients with urinary tract tuberculosis. A series of clinical and basic studies have since evaluated ileal vas deferens.In 1958, Hinman et al. studied the physiologic and metabolic effects of ileal vas deferens in a dog model. This technique further matured after the 1970s and 1980s, and a large number of clinical applications have been reported in the foreign literature [1,2]. However, this procedure has been carried out less in China. Second, indications and contraindications The indications for ileal substitution ureterotomy are usually long segment ureteral lesions that cannot be replaced by their own urinary tract tissue. Ureteral specific lesions are associated with a variety of diseases, and a meta-analysis of previous reports in the literature [Table 2] found that the top 5 etiologies for this procedure were ureteral injury due to urologic surgery (22.8%), recurrent stones (12.7%), schistosomiasis (12.2%), ureteral stenosis due to radiotherapy (10.3%), and retroperitoneal fibrosis (9%). The spectrum of diseases for which ileocecal vesicoureteral surgery is performed has changed over the years, most notably the increasing proportion of ureteral stenosis due to radiotherapy, ureteral injuries due to surgery, and the decreasing number of patients undergoing the procedure due to stones and schistosomiasis.Armatys et al. reported 91 cases of ileocecal vesicoureteral surgeries in 2009, with 43 cases of surgical vesicoureteral injuries, 17 cases of ureteral stenosis due to radiotherapy, 17 cases of ureteral stenosis due to radiotherapy, and 17 cases of abdominal fibrosis. There were 43 cases of surgical ureteral injury, 17 cases of radiation therapy-induced ureteral stenosis, 11 cases of retroperitoneal fibrosis, only 3 cases of stones, and no cases of schistosomiasis. The intestinal segments of the intestinal substitute ureter were the small intestine and the colon. The small bowel is more often used in this procedure because of the ease of freeing, anastomosis and easy identification of intraoperative supply vessels. The colon limits its use due to its potential for a variety of pathologies, such as ulcerative colitis, diverticulosis, and aspiration, but it is still an option to be considered in cases of radiolucent small bowel inflammation, and in patients with a short bowel. Relative contraindications to ileal vas deferens surgery include underlying renal insufficiency with serum creatinine greater than 2 mg/dl; bladder dysfunction or bladder outlet obstruction; and inflammatory bowel disease or radiolucent small bowel inflammation.Boxer et al. reported that of 89 cases of ileal vas deferens surgery in patients with normal preoperative renal function, only 12% developed relatively significant metabolic problems postoperatively.Chung et al. reported that in 6 cases, preoperative blood creatinine was at 2.0 mg/dl or more, three patients with postoperative renal function deterioration and three with acidosis. In patients with preoperative renal insufficiency, renal function should be improved by nephrostomy before surgery, and the use of shorter intestinal segments can reduce the emergence of postoperative metabolic complications, and should be closely followed up after surgery. The case reported in this article is a long ureteral segment injury after pneumatic ballistic lithotripsy for left ureteral stone. The preoperative renal dynamic examination showed that the left side was 28 ml/min and the right side was 40 ml/min. The preoperative blood creatinine was in the normal range, and the patient underwent nephrostomy in the left kidney to improve the left hydronephrosis. After surgery, the patient’s left hydronephrosis was improved and there was no obvious metabolic disorder. Surgical points The surgical points of ileocecal ureter replacement include: the bowel segment replaces the ureter in a parasympathetic manner, ensuring tension-free anastomosis, placing a suitable stent in the ureteral segment and placing a drain in the bladder after the operation. The need for an antireflux approach to surgery remains controversial.Shokeir et al[5] reported a prospective randomized controlled trial of 42 patients. The antireflux group used a papillary structure at the ileocecal junction. It was concluded that the antireflux procedure significantly reduced the incidence of postoperative reflux, but 21.7% (5/23) of the ileocecal papillary structures were decannulated postoperatively.In 1999, Waldner et al[6] prospectively investigated the relationship between the presence of reflux and renal function in 19 ileocecal vesicoureteral cases.Nine cases presented with vesicoureteral reflux postoperatively, but renal function improved postoperatively in all cases. The authors concluded that postoperative reflux had no significant effect on renal function, and that as long as the ileal segment taken was greater than 15 cm reflux to the renal pelvis could be avoided, and an anastomotic approach with anti-reflux was not necessary.In 2003, Brain et al[7] reported 16 cases who underwent a non-anti-reflux procedure, and no patient experienced a deterioration in the affected side of renal function or in overall renal function. It has also been reported in the literature that after ileal substitution ureterotomy, upper urinary tract stones are more easily passed and help to reduce symptoms in patients with upper urinary tract stones [8]. Therefore, in patients with stone disease who undergo this procedure, the anti-reflux procedure is generally not performed. In the case of this paper, the left side was operated with ileum instead of ureter, with no anti-reflux approach, and the ileal segment taken was 25 cm. only mild vesicoureteral reflux was observed after the operation. The left hydronephrosis improved significantly, and the renal function did not deteriorate significantly. The improvement of renal function and complications after ileal substitution ureteroplasty are not consistent in different literature reports, which are obviously related to the underlying lesion, operator experience and surgical approach, and preoperative renal function. Hyperchloremic acidosis often occurs after ileal substitution ureterotomy due to the reabsorption of urine by the intestinal mucosa and changes in the structure of the urinary tract. In addition anastomotic fistula, anastomotic stenosis, and urinary tract infection are also common complications. Cao Zhengguo [9] and Chen Rong [10] reported 21 cases of ileal substitution for urine transfusion surgery, postoperative blood creatinine were normalized, two cases of hyperchlorhydria, one case of urinary tract infection, were discharged from the hospital after treatment with medication and symptomatic treatment, and one case of postoperative mild ileal reflux of the bladder occurred. et al. reported that 16 patients (18 sides) underwent ileocecal vesicoureteral surgery, and all of them had stabilized or improved renal function after surgery, and only 2 cases developed urinary tract infections.Long-term follow-up results of 18 patients undergoing ileocecal vesicoureteral surgery were reported by Frank et al. Short-term complications (<3 months) included uretero-ileal anastomotic fistula in 2 cases, and long-term complications (>3 months) included metabolic acidosis in 2 cases, recurrent urinary tract infections in 6 cases, and fibrosis of the ileo-ureteral anastomosis in 4 cases. At 65-month postoperative follow-up, renal function had improved in 15 patients (83%), and 2 patients underwent nephrectomy of the affected side because of recurrent hematuria and multiple launch venous malformations, respectively. Fifty-six patients with intestinal pronephric ureter surgery were followed up for a mean of 6.04 months (median 3.2 months).Ten (17.9%) patients had mild postoperative complications, including pyelonephritis, fever of unknown origin, recurrent urinary stones, incisional hernia, and deep vein thrombosis.Six (10.5%) patients had more serious complications, including anastomotic stricture, obstruction of the intestinal segment of the pronephric ureter, wound dehiscence, and chronic renal failure.Renal function was stabilized or improved in 53 patients (94.6%). Ninety-one (99) ileal substitute ureter cases were followed up. The mean follow-up was 36 months.Complications occurred in 39 patients (42.9%) in the short term postoperative period (within 30 days postoperatively).Due to multiple complications in some patients, the cumulative number of complications amounted to 76, of which 14 were urinary tract infections, and 9 were wound infections.Complications were observed in 21 patients (23%) in the long term follow up. Of these, 3 (3.3%) had anastomotic stenosis and 6 (6.6%) anastomotic fistulae, all of which underwent reoperation. Another 3 cases of hyperchloremic metabolic acidosis required oral sodium bicarbonate for correction. 68 cases (74.7%) had reduced or stabilized blood creatinine after surgery. The results of the above clinical studies can confirm that the long-term results of ileal substitution ureterotomy are good, most patients have improved renal function, and the complication rate is acceptable. V. Improvement of surgical modality With the development and maturity of laparoscopic technology, laparoscopic surgery has gradually covered various fields of urology and achieved better therapeutic results. 2000, Gill et al. first reported laparoscopic ileal substitution ureterotomy. stein et al. compared the differences in perioperative efficacy between 7 cases of laparoscopic and 7 cases of open ileal substitution ureterotomy. All patients had improved renal function. Relative to open surgery, laparoscopic patients had a significantly shorter postoperative recovery time (4 weeks vs. 5.5 weeks) and a significantly lower dose of narcotic analgesics (mean dosages of 38.9 mg and 322.2 mg, respectively). In addition, the average hospitalization time was shorter in the laparoscopic group (5 and 8 days, respectively), but the average operation time was prolonged (470min and 383min, respectively), although no statistical difference was reached. Postoperative complications and biochemical and electrolyte changes were not significantly different between the two groups. Ali-el-Dein et al. from Egypt reported 10 cases of Yang-Monti method of cropping of tipped ileum in place of ureter. This procedure replaces the ureter with a small segment of ileum that is cropped and re-formed. At a mean follow-up of 9.6 months, renal function was stable or improved in all cases, and the replacement ureter drained smoothly without obstruction, with only one case of reflux. The shorter ileal segment (4-5 cm) used in this procedure reduces the intestinal mucosal area, and no cases developed hyperchloremic substitution and electrolyte disorders after the procedure. In addition, the diameter of the tailored pronephric ureter was more appropriate, which reduced the possibility of postoperative reflux. In China, Yang Jianjun et al. carried out a controlled trial on rabbits and concluded that the cropped ileal substitute ureter based on the Yang-Monti principle can be adapted to the substitution requirements of long-segment ureteral defects, and has little interference with the normal physiological function of the intestinal tract, with fewer postoperative complications, which makes it a more desirable surgical method for substituting long-segment ureteral defects. VI.CONCLUSION In conclusion, ileal substitution ureter surgery to replace the defective long-segment ureter with intestinal segments with vascularized tips has good therapeutic effect for the appropriately selected cases, and renal function can be effectively improved in the majority of the patients after surgery. The rate of postoperative complications is acceptable, including anastomotic fistula, anastomotic stricture, urinary tract infection, vesico-ileal reflux, and metabolic disorders.