Preoperative hydronephrosis is a predictive factor of ureteral stenosis after flexible ureteroscopy: a propensity scores matching analysis

Objectives Ureteral stenosis is a serious complication of flexible ureteroscopy. How to predict the possibility of stricture before surgery is an important topic. This research retrospectively studied the influence of preoperative hydronephrosis on ureteral stenosis after flexible ureteroscopy, to explore whether the preoperative hydronephrosis could predict postoperative ureteral stenosis. Methods We conducted a retrospective study on patients who received flexible ureteroscopy in our hospital for upper ureteral calculi from January 2015 to June 2018. Patients were followed-up for 36 months after surgery, and intraoperative and postoperative complications were recorded. We divided patients into the mild hydronephrosis group and moderate to severe hydronephrosis group. Preoperative clinical baseline data of the patients were adjusted by propensity matching score analysis. Differences of intraoperative ureteral injury, operative time, postoperative ureteral stricture, and SFR one month after surgery was statistically analyzed. Kaplan–Meier’s method and Log-rank test were used to compare the differences in the cumulative incidence of ureteral stenosis between the two groups. Cox regression was used to compare the hazard ratio of ureteral stenosis between the two groups. Results A total of 447 patients with 469 sides surgery were included, including 349 sides in the mild hydronephrosis group and 120 sides in the moderate to severe hydronephrosis group. Twenty-nine patients with 30 sides developed ureteral stenosis. Before and after propensity, the incidence of ureteral stricture matching analysis was 6.4% and 8%, respectively. There were statistical differences in ureteral stricture and injury, but the statistical differences in SFR and operation time were inconsistent. Kaplan–Meier showed a significant difference in the cumulative incidence of ureteral stenosis between the two groups. Conclusions Patients with moderate to severe hydronephrosis before surgery were more likely to have an intraoperative ureteral injury and postoperative ureteral stricture after FRUS. Preoperative hydronephrosis is an important predictor of ureteral stricture.

Congenital midureteral stenosis in children: a 13-year retrospective study based on data from a large pediatric medical center

Background Midureteral stenosis is very rare in children and can cause congenital hydronephrosis. We report our experience treating children with congenital midureteral stenosis at our center, focusing on the differences in preoperative diagnosis and treatment compared with other congenital obstructive uropathies. Methods We retrospectively reviewed the medical records of 26 children diagnosed with congenital midureteral stenosis at our center between January 2007 and December 2020, such as preoperative examination methods, intraoperative conditions, and postoperative follow-up results. Results Of the 1625 children treated surgically for ureteral narrowing, only 26 (1.6%) were diagnosed with midureteral stenosis, including 15 infants and 11 children. Eighteen (69.2%) were boys, 13 (50%) were affected on the left side, and 23 (88.5%) had isolated ureteral stenosis. Overall, 13 (50%) of the children presented with prenatal hydronephrosis, and 13 (50%) presented with abdominal pain or a mass. All the children had undergone urinary ultrasound and intravenous urography preoperatively; the diagnostic rate of ultrasound was 92.3%. Only 7 (26.9%) children had undergone pyelography. All the children had undergone surgery. The ureteral stenotic segment was less than 1 cm long in 25 (96.2)% of the children. The mean follow-up duration was 22 months (range: 6–50 months). One child developed anastomotic strictures. Urinary tract obstruction was relieved in the other children without long-term complications. Conclusions Congenital midureteral stenosis is rare, accounting for 1.6% of all ureteral obstructions, and its diagnosis is crucial. Urinary ultrasound has a high diagnostic rate and should be the first choice for midureteral stenosis. Retrograde pyelography can be used when the diagnosis is difficult, but routine retrograde pyelography is not recommended. Congenital ureteral stenosis has a relatively short lesion range, largely within 1 cm. The treatment is mainly resection of the stenotic segment and end-to-end ureteral anastomosis, with a good prognosis.

A Case of Elastography-Assisted Laparoscopic Fertility Preservation for Severe Deep Endometriosis Causing Ureteral Stenosis and Subtype II Adenomyosis

Adenomyosis is commonly treated by total hysterectomy. Adenomyomectomy is considered for women of reproductive age who wish to preserve their fertility. However, a high recurrence rate following adenomyomectomy has been reported because complete removal of the lesion is difficult, and uterine rupture during pregnancy remains a complication. We previously reported that laparoscopic adenomyomectomy using a cold knife prevented thermal damage to the myometrium and elastography to avoid residual lesions. Here, we report the case of a patient who underwent complete resection of a subtype II adenomyosis and resection of deep endometriosis (DE) with the closure of the pouch of Douglas. The patient was 31 years old, had severe dysmenorrhea, and had left ureteral stenosis and subtype II adenomyosis associated with the closure of the pouch of Douglas by the DE. After resection of the DE posterior wall adenomyosis, residual lesions were confirmed by laparoscopic real-time elastography. Eight weeks after surgery, postoperative transvaginal ultrasound showed that the myometrium had shrunk from 28 to 22.7 mm, and the hydronephrosis had disappeared, although a stent remained necessary. In this study, we report the complete resection of subtype II adenomyosis and DE, combined with elastography to visualize the lesions during resection.

Congenital Midureteral Stenosis in Children: A 13-year Retrospective Study based on Data from a Large Pediatric Medical Center

Background: Midureteral stenosis is very rare in children and can cause congenital hydronephrosis. We report our experience treating children with congenital midureteral stenosis at our center, focusing on the differences in preoperative diagnosis and treatment compared with other congenital obstructive uropathies.Methods: We retrospectively reviewed the medical records of 26 children diagnosed with congenital midureteral stenosis at our center between January 2007 and December 2020, including preoperative examination methods, intraoperative conditions, and postoperative follow-up results.Results: Of the 1625 children treated surgically for ureteral narrowing, only 26 (1.6%) were diagnosed with midureteral stenosis, including 15 infants and 11 children; 68% were boys; 48% were affected on the left side; and 88% had isolated ureteral stenosis. In all, 50% of the children presented with prenatal hydronephrosis, and 50% presented with abdominal pain or a mass. All children underwent urinary ultrasound and intravenous urography (IVU) preoperatively; the diagnostic rate of ultrasound was 92.3%. Only 7 (26.9%) children underwent pyelography. All children underwent surgery. The ureteral stenotic segment was less than 1 cm long in 96% of the children. The mean follow-up duration was 22 months (range: 6-50 months). One child developed anastomotic strictures. Urinary tract obstruction was relieved in the other children without long-term complications.Conclusions: Congenital midureteral stenosis is rare, accounting for 1.6% of all ureteral obstructions, and its diagnosis is very important. Urinary ultrasound has a high diagnostic rate and should be the first choice for midureteral stenosis. Retrograde pyelography can be used when diagnosis is difficult, but routine retrograde pyelography is not recommended. Congenital ureteral stenosis has a relatively short lesion range, largely within 1 cm. The treatment is mainly resection of the stenotic segment and end-to-end ureteral anastomosis, with a good prognosis.

Effect of Preoperative Hydronephrosis on Ureteral Stenosis after Flexible Ureteroscopy: A Propensity Scores Matching Analysis

OBJECTIVES: Ureteral stenosis is a serious complication after flexible ureteroscopy. Other studies have confirmed that stone impaction and intraoperative ureteral injury are important factors causing stricture, and how to predict the occurrence of stricture before surgery may be an important topic. This study retrospectively studied the influence of preoperative hydronephrosis degree on ureteral stenosis after flexible ureteroscopy to explore whether preoperative hydronephrosis degree could predict postoperative ureteral stenosis. METHODS: A retrospective study was conducted on patients who received flexible ureteroscopy in our hospital for upper ureteral calculi from January 2015 to June 2018. The postoperative follow-up was performed for 36 months, and intraoperative and postoperative complications were recorded. According to the degree of hydronephrosis, the patients were divided into mild hydronephrosis group and moderate and severe hydronephrosis group. Preoperative clinical baseline data of the patients were adjusted by propensity matching score, and differences in intraoperative mucosal injury, operative time, incidence of postoperative ureteral stricture, and SFR 1 month after surgery were statistically analyzed. Kaplan-Meier method and Log-rank test were used to compare the differences in the cumulative incidence of ureteral stenosis between the two groups. Cox regression analysis was used to compare the hazard ratio of ureteral stenosis between the two groups. RESULTS: A total of 447 patients with 469 sides surgery were included, including 349 sides in the mild hydronephrosis group and 120 sides in the moderate and severe hydronephrosis group. 30 sides in 29 patients developed ureteral stenosis. The stenosis rate before propensity matching analysis was 6.4%, and 8% after propensity matching analysis. However, the SFR and operation time were not statistically consistent. Kaplan-Meier showed a significant difference in the cumulative incidence of ureteral stenosis between the two groups.CONCLUSIONS: Preoperative patients with moderate to severe hydronephrosis are more likely to have intraoperative mucosal injury, and the incidence of ureteral stricture is higher after flexible ureteroscopy. Preoperative hydronephrosis is an important predictor of ureteral stricture. Preoperative hydronephrosis is an important predictor of ureteral stricture.

Effect of Nanobubble-Based Ultrasound Imaging Technology on the Treatment of Ureteral Stenosis

In order to explore the effect of nanobubble-based ultrasound imaging technology on the treatment of ureteral stenosis, a total of 120 patients, who were confirmed as ureteral stenosis by surgery, pathology or multiple imaging examinations at a designated hospital of the study from December 2015 to December 2018, were selected as research objects and were divided into three groups of targeted nanobubble (TN) group, blank nanobubble (BN) group and control (CT) group with 40 cases in each group. The TN group utilized the nanobubbles with a particle size of (499.52±72.87) nm as carriers to compare and analyze patients’ ultrasound images for the predisposition and etiology of ureteral stenosis and the sonogram variations of hydronephrosis, renal pelvis; the BN group utilized the blank nanobubble with a particle size of (446.71±45.36) nm as carriers to perform ultrasound imaging and diagnostic analysis of ureteral stenosis; the CT group directly conducted ureteral stenosis treatment with ultrasound imaging technology. The results showed that the total coincidence rates of the targeted diagnosis for ureteral stenosis of the TN, BN and CT group were 94.38%, 87.52%, and 67.94%, respectively; the coincidence rates of different examination methods for different diagnostic parts were different and the diagnostic coincidence rates of TN group for pelvic ureteral transition area, end of ureter, and the area between pelvic ureteral transition area and end of ureter were 82.91%, 79.66%, and 75.17%, respectively; the diagnostic coincidence rates of BN group for those were 80.32%, 94.77%, respectively and 92.18% and the CT group were 58.66%, 72.14%, and 66.48%, respectively; the diagnosis coincidence rates for ureteral stenosis etiology of the TN, BN and CT group were 93.81%, 82.66% and 64.57%, respectively. Therefore, it was believed that the nanobubble-based ultrasound examination can accurately diagnose the site of ureteral stenosis through the exploration of hydronephrosis and ureteral dilatation with the advantages of simplicity, no pain, repeatable examination, and no impact on renal function, and having high clinical value for diagnosing ureteral stenosis.