Objective To analyze the characteristics of medically-induced ureteral injuries and summarize the experience of prevention, diagnosis and treatment of medically-induced ureteral injuries. Methods To analyze the cause of injury, location, treatment time, method, and treatment results of 17 cases of medical-origin ureteral injuries admitted between 1997 and 2003. Results Among the 17 cases of medically originated ureteral injuries, gynecology, general surgery, and endoluminal urology led to ureteral injuries in 12 (70.6%), 4 (23.5%), and 1 (5.9%) cases, respectively, of which 66% (11/17) appeared in the lower part of the ureter, 17% (3/17) appeared in the middle part of the ureter, and 17% (3/17) appeared in the upper part of the ureter; the modes of injuries were Ligation, angulation, dissection, and perforation in 5 (29%), 7 (41%), 4 (24%), and 1 (6%) cases, respectively; 4 cases were detected intraoperatively, 9 cases were detected 2-11 days postoperatively, and 4 cases were diagnosed and treated at 3 months to 6 months postinjury; 7 cases of anastomosis of severed ends of the ureter, 3 cases of reimplantation of ureteral bladder, 1 case of ureteral exploratory lithotripsy, and 3 cases of ureteral laxation alone were detected and treated, 3 cases of simple ureteral loosening, 3 cases of double J tube placement after loosening; all the operations in this group were successful, with follow-up from 6 months to 3 years, and none of them had urinary tract infection, hydronephrosis and decreased renal function. Conclusion The site and type of ureteral injury determine the mode of treatment; a comprehensive understanding of ureteral anatomy is the key to preventing ureteral injury; when ureteral injury occurs, mastering the diagnostic steps and familiarizing oneself with the principles of treatment are the core of improving the cure rate of medically induced ureteral injury. Trauma and injury; Ureter; Diagnosis; Urologic surgical methods; Medical-origin injury Medical-origin ureteral injury is the main cause of ureteral injury, especially after delayed diagnosis and treatment, it is prone to a high level of complications, whether it is post-injury ureteral obstruction or urinary extravasation, which can lead to impaired nephrokinesis and infections, which may affect the quality of life in the less severe cases, or even endanger life in severe cases of serious damage to the kidneys on the injured side. We summarize the information of 17 cases of medically induced ureteral injuries admitted from 1997 to 2003, with satisfactory clinical treatment results, and hereby report the relevant clinical data and discuss them with the literature as follows. 1, clinical information 1.1, general information 15 cases of women and 2 cases of men in this group, age 27-68 years old, average 45 years old. There were 12 cases due to obstetrics and gynecology surgery, accounting for 71%, including 10 cases of hysterectomy and 2 cases of ovarian cyst removal; 1 case each of colon cancer and adhesion to the upper and middle ureter in general surgery, 2 cases of left lower ureteral injuries due to radical surgery of rectal cancer (Mile’s surgery), and 1 case of perforation of the upper part of the ureter due to ureteroscopy of endoluminal ureteroscope with gas-pressure ballistic lithotripsy. The time of discovery of ureteral injury in this group of patients: 4 cases were discovered during surgery, 9 cases were discovered 2-11 days after surgery, and 4 cases were diagnosed and treated at 3 months to half a year. Clinical manifestations included fever, low back pain, epigastric discomfort, nausea, vaginal leakage, hydronephrosis; examinations included routine laboratory tests, biochemistry, ultrasound, IVP, retrograde urography of the upper urinary tract, MRU, or/and CT. 1．2．Treatment Seventeen patients were subjected to ureteral exploration and treatment surgery after definitive diagnosis, and ureteral injuries were found intraoperatively in the form of ligature, pulling at an angle after partial ligature, disarticulation, and perforation. 5 (29%), 7 (41%), 4 (24%), and 1 (6%) cases, respectively. Four patients were found intraoperatively: one case of ureteroscopic perforation injury, change position for exploration of the upper ureter, incision above the stone to remove the stone, the perforation was not treated, and a double J-tube stent was placed to drain urine; one case of abdominal tumor adhesion with the ureter, one case of intraoperative dissection, one case of loosening, and one case of anastomosis of the severed end of the ureter; one case of gynecologic tumor found at the end of the surgery, there was non-haematogenous fluid leaking out of the abdominal cavity, and it was suspected that there was a ureteral injury, and a partial ligation leakage of the lower part of the ureter was found during the exploration, and a loose end was found in one case. The ureter was partially ligated for leakage of urine, and the ureter was loosened and a drain was placed around it in 1 case. Nine patients were found 2-11 days after surgery: edema and adhesion of different degrees in the tissues around the ureter were detected, 1 case of simple ureteral release, 3 cases of double J-tube drainage were placed after release, 3 cases of end-to-end anastomosis of the ureter, and 2 cases of reimplantation of the ureteral bladder were found, and all of them were placed with double J-tube drainage during the anastomosis. The other 4 cases were diagnosed 3 months to 6 months after the operation: 1 case of ureterovaginal fistula with ureteral end-to-end anastomosis and 1 case of ureteral bladder reimplantation; 2 cases of hydronephrosis and lower ureteral obstruction with ureteral end-to-end anastomosis. 2.Results There were no fatal cases in this group, and there were no complications in the reoperation patients. All patients were followed up for 6 months to 3 years, none of them had urinary tract infection, none of them had hydronephrosis aggravation or decreased renal function, and the results were satisfactory. 3, Discussion 3.1, the incidence of medical ureteral injury Traumatic ureteral injury is relatively rare, but ureteral injury caused by abdominal, pelvic and endoluminal urological surgery occurs from time to time. A recent statistical report showed that the incidence of ureteral injuries due to open abdominal and pelvic surgery ranged from 0.1 to 2.5%, ureteral injuries originating from gynecologic surgery accounted for 75%, injuries originating from general surgery accounted for 20%, and other causes (e.g., endoluminal urology) accounted for about 5% [1]. In recent years, with the introduction of the concept of minimally invasive surgery and the development of various forms of treatment, there is a trend of elevated ureteral injuries of laparoscopic origin. Although no large number of cases have been counted so far, Assimos [2] reported that the incidence of ureteral injuries caused by laparoscopy was 0.5%, and that of ureteral injuries caused by ureteroscopy was 3.0%; the incidence of injuries caused by gynecological laparoscopy was 25% of the total. Injuries caused by gynecologic laparoscopy accounted for 25% of the total incidence. Among the ureteral injuries in this group, 70.6% (12/17), 23.5% (4/17), and 5.9% (1/17) of the injuries were caused by gynecology, general surgery, and endoluminal urology, respectively, which are similar to those reported in the literature. 3.2, Sites and causes of ureteral injury The common site of ureteral injury is the distal 3 cm of the ureter, which is 0.5-2.1 cm from the cervix in females, and the ureter crosses the main ligament at the uterine vessels [1], and the other common sites of injury are the ureter into the pelvic rim, and the upper and middle portions of the ureter, respectively. Ureteral injury often occurs when the operator tries to control bleeding, at this time, due to the deep pelvic location, exposure difficulties, as well as bleeding when the surrounding tissue relationship is unclear, easy to ureteral injury; in addition, malignant tumors adhesion, enlarged uterus, non-normal dissection, as well as pelvic organs prolapse, etc., most of these cases change the normal anatomical relationship of the ureter and its surrounding, separating the tissue difficulties resulting in ureteral injury; entry into the mirror Improper access, forced maneuvering, blind catheter insertion, and careless operation of lithotripter are important causes of ureteral luminal injuries. The most common types of injury reported in the literature were ligation, suture pulling, followed by clamping, loss of blood supply, compression and dissection. 17 cases in this group were injured by ligation, pulling at an angle, dissection, and perforation in 5, 7, 4, and 1 cases, respectively. 3.3 Diagnosis of ureteral injury Ureteral fracture injury is often manifested intraoperatively by the presence of persistent clear fluid in the operative field, and sometimes tubular breaks or fissures can be seen. Most of the other types of ureteral injuries do not have special performance at the time of operation, and can only rely on the operator’s feeling and experience, any suspected ureteral injuries, one of the more reliable methods is to rely on the intravenous injection of indigo cochineal combined with cystoscopic examination of the ureteral spraying situation, to determine whether the ureter is damaged. In postoperative ureteral injury, early signs are often fever, low back pain in the flank area, persistent bowel obstruction, ascites, hematuria and anuria, and increased serum creatinine; late clinical signs include urinary cysts, ureteral fistulae formation (e.g., vaginal, intestinal, or cutaneous leakage of urine), and hydronephrosis and renal atrophy secondary to stenosis [6]. Diagnostic tests to evaluate ureteral injuries include laboratory tests, cystoscopy, and imaging techniques. Elevated blood creatinine of 0.8-1.0 mg/dL has been reported 24-72 hours after unilateral ureteral ligation [3].IVP is useful in evaluating hydronephrosis, unilateral renal function, and the continuity of the ureteral integrity; however, 7% of cases after ureteral injury show a normal IVP [6].In comparison, retrograde ureterography has an almost 100% rate of correctness in the diagnosis of ureteral injuries, and it is able to CT, urinalysis and cystoscopy are indispensable in the diagnosis and can assist retrograde ureterography to clarify the diagnosis; ultrasound has no advantage in showing ureteral injury, but it can indicate the presence of hydronephrosis. Once ureteral injury is diagnosed intraoperatively, the site, degree and type of injury should be evaluated first. In general, clamp injury or ligature pulling into the angle if there is no ischemia and necrosis, simple loosening or placing a ureteral stent tube for 7-10 days, in order to prevent postoperative ureteral stenosis; if there is ischemia and necrosis, the injured end of the ureter needs to be trimmed, and then treated the same as the treatment of discrete injuries, i.e., end-to-end anastomosis or uretero-cystocele anastomosis. A partially dissected ureter requires adequate freeing, can be spoon-shaped end-to-end anastomosis, and if the injury occurs in the ureter proximal to the bladder where it is not easily manageable, a ureterocystograft is performed. The management of complete ureteral dissection is based on the level of injury, Payne [4] suggests that ureteral end-to-end anastomosis is performed when the injury is located more than 5 cm from the ureterobladder junction, and conversely ureterocystocele anastomosis is easy to perform when the location is less than 5 cm. The anastomosis should be performed with non-invasive forceps, freshly trimmed anastomotic ends to avoid unnecessary resection, moderate anastomotic tension, and internal stent drainage with a double-J tube. In our group, all kinds of anastomoses were drained with double J tube internal stent except simple loosening, which has the advantages of simple operation, fast recovery, and reduction of postoperative complications. According to the operator’s experience and the patient’s clinical manifestations, the diagnosis of ureteral injury may be early or late, and the treatment method of our group shows that the earlier the diagnosis, the simpler the operation is performed. If the injury is detected during the operation, most of the operations are performed with loosening and draining, and more than 3 months after the operation, ureteral anastomoses and ureterocystic anastomoses are often performed. When the diagnosis of medical ureteral injury has been delayed, ureteral repair does not have to be performed immediately at the time of diagnosis, most of the literature [4-5] believe that the injury is diagnosed at 72 hours after surgery, and can be repaired immediately; the injury is diagnosed in 1~2 weeks, such as the patient’s condition permits, but also can be immediately surgical exploration; when the injury is clearly diagnosed in more than 2 weeks, in order to avoid the serious tissue edema and adhesion, and anastomoses are prone to ischemia and necrosis In order to avoid serious tissue edema and adhesion, the anastomosis is prone to ischemic necrosis and urine leakage, it is advisable to perform percutaneous nephrostomy on the injured side first to drain the urine from the kidney, and the best way to repair the injury is to do it at 8-12 weeks. Contraindications to immediate repair of ureteral injury include deferred diagnosis of ureteral injury for more than 2 weeks, poor general condition, recent pelvic surgery on the affected side, and postoperative infection. Pathophysiology confirms the emergence of neoplastic migratory epithelium in the ureteral anastomosis at two weeks and the formation of peristalsis at four weeks [3]. Post-ureteral repair management involves bladder catheter drainage, and Foley’s urinary catheter can be removed if periureteral drainage is less than 30 ml; routinely, the catheter is left in place for 2-3 days when the bladder is not opened for repair surgery, and for 7-10 days when the bladder is opened. If periureteral drainage increases after removal of the urinary catheter, the catheter needs to be repositioned; conversely, if there is no increase, the periureteral drain can be removed. Intraureteral drainage double J tube usually needs to be placed for 3~6 weeks, all catheters are removed and IVP is done after one month, IVP suggests normal, and later ultrasound is done for 3~6 months for follow up. Obviously, the best treatment for ureteral injury is prevention. Familiarity with ureteral anatomy and meticulous intraoperative operation are the keys to preventing ureteral injury, while adequate exposure of the operative field is the prerequisite for avoiding blind operation. If the pelvic ureter is not easily visible, the Grave’s avascular zone of the posterior peritoneum should be exposed in women, and by separating the round ligament and freeing the peritoneum parallel to the pelvic funnel ligament and the posterior broad ligament of blood vessels, the lower part of the ureter located at the middle lobe of the posterior broad ligament can be easily recognized; in addition, there is also a conventional method of the ureter into the pelvic rim across the iliac vessels, which is superficial and easy to identify the location of the ureter. The ureter is superficial and easily recognized. Many physicians consider routine separation, palpation, and visualization of the ureter to be essential to avoid ureteral injury in abdominal and pelvic surgery.