Dual outflow upper arm arteriovenous fistula: An effective technique to prevent cephalic arch stenosis.

Cephalic arch stenosis (CAS) is critical point to maintain functional arteriovenous fistula (AVF) in patients undergoing hemodialysis with brachio-cephalic AVFs. In this study, we aimed to determine the effectiveness of dual outflow (cephalic and basilic veins) as a surgical method to prevent CAS. Between July 2016 and December 2019, 369 patients underwent upper arm AVF creation. Among them the 251 patients were enrolled in this retrospective study. Two hundred seven underwent brachio-cephalic arteriovenous fistula (BCAVF) and 44 underwent brachio-cephalicbasilic arteriovenous fistula (BCBAVF). From the 251 patients, diabetes mellitus (66.7% vs 36.4%, P < .001) and hypertension (91.3% vs 75%, P = .002) were more common in the patient group who underwent BCAVF surgery; however, the difference in volume flow to the fistula did not differ between the 2 groups. CAS (30.4% vs 9.1%, P = .004) and fistula occlusion (15.9% vs 4.5%, P = .048) were likely to occur in the BCAVF group. The primary patency rates at 12 months were 74.3% and 86.4% for the BCAVFs and BCBAVFs, respectively (P = .075). The primary-assisted patency rates at 12 months were 87.0% for BCAVFs and 93.2% for BCBAVFs, respectively (P = .145). Secondary patency rates at 12 months were 92.2% for BCAVFs and 93.2% for BCBAVFs, respectively (P = .023). Compared to BCAVF, traditional upper arm AVF, upper arm AVF with cephalic and basilic vein dual drainage can be optimal surgical method to preventing CAS.

Prevention of Rectal Stenosis After Procedure for Prolapse and Hemorrhoids by Anastomotic Thread-Drawing and Anal Enlargement.

PURPOSE: to investigate preventive measures of rectal stricture after procedure for prolapse and hemorrhoids (PPH) and to intervene early. METHODS: A total of 400 patients with severe mixed hemorrhoids hospitalized in the [anonymous hospital] from January 2018 to February 2022 were randomly divided into the experimental group and control group A, B, and C, with 100 patients in each group. Experimental group: Thread-drawing during operation and anal enlargement after PPH. Group A: Thread-drawing during PPH surgery, group B: Anal enlargement after PPH, and group C: PPH alone. The anastomotic sites of the 4 groups were observed for 1-2 months and followed up for 1-3 years. RESULTS: The effective rate of mixed hemorrhoid treatment in the 4 groups was 100%. There was no rectal stenosis in the experimental group, 11% in group A, 7% in group B, and 14% in group C. CONCLUSION: Multipoint thread-drawing and anal enlargement after PPH can avoid postoperative rectal stenosis and can strengthen anastomosis and reduce bleeding, while being a simple procedure that can be easily popularized.

Modified Collard technique is more effective than circular stapled for cervical esophagogastric anastomosis in prevention of anastomotic stricture: a propensity score-matched study.

The anastomotic technique after esophagectomy is of great interest in the prevention of anastomotic complications that adversely affect postoperative recovery. This study aimed to compare the clinical outcomes of modified Collard (MC) and circular stapled (CS) anastomoses after esophagectomy. A total of 504 consecutive patients with thoracic esophageal cancer who underwent esophagectomy and cervical esophagogastric CS or MC anastomosis from January 2013 to December 2019 were enrolled. Out of 504 patients, 134 and 370 underwent CS and MC anastomoses. The frequency of anastomotic leakage and stricture was significantly lesser in the MC group than in the CS group (3.0 vs. 10.5%, P = 0.0014 and 11.1 vs. 34.3%, P < 0.001, respectively). CS anastomosis was an independent risk factor for anastomotic stricture (odds ratio, 4.89; P < 0.001). Oral intake was significantly higher in the group without anastomotic stricture than in the group with anastomotic stricture at 2, 3, and 6 months postoperatively (P < 0.001, P = 0.013, and P < 0.001, respectively). The percentage body weight loss (%BWL) was -12.2% in the group with anastomotic stricture and -7.5% in the group without anastomotic stricture at 3 months postoperatively (P = 0.0012). Anastomotic stricture was an independent factor associated with %BWL (odds ratio, 4.86; P = 0.010). Propensity score-matched analysis, which included 88 pairs of patients, confirmed a significantly lower anastomotic stricture rate in the MC group than in the CS group (10.2 vs. 35.2%, P < 0.001). MC anastomosis is better than CS anastomosis for reducing the frequency of anastomotic stricture, which may be useful for maintaining early postoperative nutritional status.

Mixed-methods feasibility study to inform a randomised controlled trial of proton pump inhibitors to reduce strictures following neonatal surgery for oesophageal atresia.

OBJECTIVES: This mixed-methods feasibility study aimed to explore parents' and medical practitioners' views on the acceptability and design of a clinical trial to determine whether routine prophylactic proton pump inhibitors (PPI) reduce the incidence of anastomotic stricture in infants with oesophageal atresia (OA). DESIGN: Semi-structured interviews with UK parents of an infant with OA and an online survey, telephone interviews and focus groups with clinicians. Data were analysed using reflexive thematic analysis and descriptive statistics. PARTICIPANTS AND SETTING: We interviewed 18 parents of infants with OA. Fifty-one clinicians (49 surgeons, 2 neonatologists) from 20/25 (80%) units involved in OA repair completed an online survey and 10 took part in 1 of 2 focus groups. Interviews were conducted with two clinicians whose survey responses indicated they had concerns about the trial. OUTCOME MEASURES: Parents and clinicians ranked the same top four outcomes ('Severity of anastomotic stricture', 'Incidence of anastomotic stricture', 'Need for treatment of reflux' and 'Presence of symptoms of reflux') as important to measure for the proposed trial. RESULTS: All parents and most clinicians found the use, dose and duration of omeprazole as the intervention medication, and the placebo control, as acceptable. Parents stated they would hypothetically consent to their child's participation in the trial. Concerns of a few parents and clinicians about infants suffering with symptomatic reflux, and the impact of this for study retention, appeared to be alleviated through the symptomatic reflux treatment pathway. Hesitant clinician views appeared to change through discussion of parental support for the study and by highlighting existing research that questions current practice of PPI treatment. CONCLUSIONS: Our findings indicate that parents and most clinicians view the proposed Treating Oesophageal Atresia with prophylactic proton pump inhibitors to prevent STricture (TOAST) trial to be feasible and acceptable so long as infants can be given PPI if clinicians deem it clinically necessary. This insight into parent and clinician views and concerns will inform pilot phase trial monitoring, staff training and the development of the trial protocol.

Gastroduodenal artery disconnection during liver transplantation decreases non-anastomotic stricture incidence.

BACKGROUND: The hepatic artery is the only blood source nourishing the biliary duct and associated with biliary complication after liver transplantation (LT). Gastroduodenal artery (GDA) disconnection increased proper hepatic artery flow. Whether this procedure attenuates biliary non-anastomotic stricture (NAS) is not clear. METHODS: A total of 241 patients with LT were retrospectively analyzed. The patients were divided into the GDA disconnection (GDA-) and GDA preservation (GDA+) groups. Propensity score matching (PSM) was administrated to reduce bias. Logistic regression was conducted to analyze risk factors for biliary NAS before and after PSM. Postoperative complications were compared. Kaplan-Meier survival analysis and log-rank tests were performed to compare overall survival. RESULTS: In all, 99 patients (41.1%) underwent GDA disconnection, and 49 (20.3%) developed NAS. Multivariate logistic regression revealed that GDA preservation (OR = 2.24, 95% CI: 1.11-4.53; P = 0.025) and model for end-stage liver disease (MELD) score > 15 (OR = 2.14, 95% CI: 1.12-4.11; P = 0.022) were risk factors for biliary NAS. PSM provided 66 pairs using 1:2 matching method, including 66 GDA disconnection and 99 GDA preservation patients. Multivariate logistic regression after PSM also showed that GDA preservation (OR = 3.15, 95% CI: 1.26-7.89; P = 0.014) and MELD score > 15 (OR = 2.41, 95% CI: 1.08-5.36; P = 0.031) were risk factors for NAS. When comparing complications between the two groups, GDA preservation was associated with a higher incidence of biliary NAS before and after PSM (P = 0.031 and 0.017, respectively). In contrast, other complications including early allograft dysfunction (P = 0.620), small-for-size graft syndrome (P = 0.441), abdominal hemorrhage (P = 1.000), major complications (Clavien-Dindo grade ≥ 3, P = 0.318), and overall survival (P = 0.088) were not significantly different between the two groups. CONCLUSIONS: GDA disconnection during LT ameliorates biliary NAS incidence and may be recommended for application in clinical practice.

Closure of large mucosal defects for prevention of strictures after duodenal endoscopic submucosal dissection (with video).

BACKGROUND AND AIMS: Although lesions occupying a large circumference are associated with the risk of post-endoscopic submucosal dissection (ESD) strictures, the corresponding data for duodenal lesions are unknown. We aimed to analyze the incidence of post-ESD strictures after wide-field duodenal ESD. METHODS: In this retrospective study of duodenal lesions treated with ESD between July 2010 and August 2021, we included lesions that resulted in mucosal defects occupying more than half of the circumference and excluded lesions located in bulbs and involving Vater's papilla. We analyzed the incidence rates of stricture and luminal narrowing, in addition to bleeding and perforation as the outcomes in this study. Stricture was defined as the inability of the endoscope to pass through the lumen. A single endoscopist reviewed all endoscopic images and judged the degree of luminal narrowing. RESULTS: Eighty lesions were included, of which 2 involved mucosal defects occupying more than 90% of the circumference. The wound was closed, at least partially, in 90% in all lesions and in 86% of lesions with a mucosal defect occupying more than 75% of the circumference. None of the lesions caused delayed perforation and stricture, whereas 2 lesions caused delayed bleeding. Only 6 lesions caused luminal narrowing. When examined by the degree of closure, the rate of luminal narrowing increased with complete closure, incomplete closure, and nonclosure (4.9%, 9.1%, and 25.0%, respectively). CONCLUSIONS: Suturing may prevent post-ESD bleeding and perforation as well as stricture formation in cases of duodenal tumors, with mucosal defects occupying a large circumference.

Acid suppression duration does not alter anastomotic stricture rates after esophageal atresia with distal tracheoesophageal fistula repair: A prospective multi-institutional cohort study.

INTRODUCTION: Anastomotic stricture is the most common complication after esophageal atresia (EA) repair. We sought to determine if postoperative acid suppression is associated with reduced stricture formation. METHODS: A prospective, multi-institutional cohort study of infants undergoing primary EA repair from 2016 to 2020 was performed. Landmark analysis and multivariate Cox regression were used to explore if initial duration of acid suppression was associated with stricture formation at hospital discharge (DC), 3-, 6-, and 9-months postoperatively. RESULTS: Of 156 patients, 79 (51%) developed strictures and 60 (76%) strictures occurred within three months following repair. Acid suppression was used in 141 patients (90%). Landmark analysis showed acid suppression was not associated with reduction in initial stricture formation at DC, 3-, 6- and 9-months, respectively (p = 0.19-0.95). Multivariate regression demonstrated use of a transanastomotic tube was significantly associated with stricture formation at DC (Hazard Ratio (HR) = 2.21 (95% CI 1.24-3.95, p<0.01) and 3-months (HR 5.31, 95% CI 1.65-17.16, p<0.01). There was no association between acid suppression duration and stricture formation. CONCLUSION: No association between the duration of postoperative acid suppression and anastomotic stricture was observed. Transanastomotic tube use increased the risk of anastomotic strictures at hospital discharge and 3 months after repair.

Novel vaginoplasty technique involving the use of peritoneal flaps during laparoscopic radical hysterectomy for early-stage cervical cancer.

Radical hysterectomy is often performed to treat early-stage cervical cancer in women of reproductive age, and sexual dysfunction due to postoperative vaginal shortening is a major concern [1,2]. Vaginoplasty using various techniques is commonly performed in patients with congenital vaginal agenesis [3]. However, there are few reports of vaginoplasty being performed for vaginal shortening after radical hysterectomy in a patient with cervical cancer [4,5]. We demonstrate a novel vaginoplasty technique in which peritoneal flaps are used during laparoscopic radical hysterectomy to prevent postoperative vaginal shortening and consequent sexual dysfunction in patients with early-stage cervical cancer. A 37-year-old woman with early-stage cervical cancer who wished to perform sexual activity postoperatively underwent laparoscopic radical hysterectomy and vaginoplasty. After radical hysterectomy, the residual vaginal length was 4 cm. The dissected peritoneum of pouch of Douglas (posterior peritoneal flap) was sutured to the posterior vaginal stump. The supravesical peritoneum was dissected from the ventral to the dorsal side to create an anterior peritoneal flap, which was inverted, pulled down, and sutured to the anterior vaginal stump. The anterior peritoneal flap and suprarectal peritoneum were sutured to create a 10-cm neovaginal vault. Subsequently, a methacrylic resin mold was inserted into the neovagina to prevent postoperative neovaginal stenosis. The patient had sexual intercourse 3 months postoperatively. She was satisfied with the sexual activity and experienced no vaginal shortening or stenosis. Our novel vaginoplasty technique is feasible and effective for preventing sexual dysfunction by lengthening the vagina during laparoscopic radical hysterectomy for early-stage cervical cancer. Trial Registration: Japan Registry of Clinical Trials Identifier: jRCT1030210227.

Circular Stapler Method for Avoiding Stricture of Cervical Esophagogastric Anastomosis.

BACKGROUND: This study was performed to verify the superiority of a new "non-tensioning method" for avoiding stricture of the cervical esophagogastric anastomosis by circular stapling compared with the conventional method. METHODS: In total, 395 consecutive patients who underwent McKeown esophagectomy with gastric conduit (GC) reconstruction were reviewed. A 4 cm-wide GC was created and pulled up at the cervical site through the retrosternal route. The esophagogastrostomy site of the GC was planned as far caudally as possible on the greater curvature side. In the conventional technique, the stapler was fired while pulling the GC to avoid tissue slack. In the non-tensioning technique, the stapler was fired through the natural thickness of the stomach wall. The length of the blind end was changed from 4 to 2 cm in the non-tensioning technique. Anastomotic leakage and stricture formation were compared between the two techniques, and adjustment was performed using propensity score matching. RESULTS: The conventional group comprised 315 patients, and the non-tensioning group comprised 80 patients. Anastomotic leakage occurred in 22 (7%) and 2 (2.5%) patients, respectively (P = 0.134) [and in 9 (2.9%) and 2 (2.5%) patients, respectively, if leakage at the blind end was excluded]. Anastomotic stricture occurred in 92 (29.2%) and 3 (3.8%) patients, respectively (P < 0.001). The propensity score-matching analysis including 79 pairs of patients confirmed a lower stricture rate in the non-tensioning than conventional group (2.5% vs. 29.1%, P < 0.001). CONCLUSIONS: The non-tensioning technique significantly reduced the incidence of anastomotic stricture compared with the conventional technique.

Ureteral stents cannot decrease the incidence of ureteroileal anastomotic stricture and leakage: A systematic review and meta-analysis.

BACKGROUND: The ileal conduit and ileal orthotopic neobladder were the most popular methods for urinary diversion following radical cystectomy. Stenting the anastomosis of ileo-ureter or ureter-neobladder was a common practice. However, it is still controversial if ureteral stents could prevent complications such as ureteroileal anastomosis stricture (UIAS) and ureteroileal anastomosis leakage (UIAL) after ureteral anastomosis. OBJECTIVES: This study aims to investigate the role of the ureteral stent in preventing UIAS and UIAL. DATA SOURCES: We systematically searched the related studies in PubMed, Embase, and Cochrane Library up to June 2020. STUDY ELIGIBILITY CRITERIA: Cohort studies that identified the use of stent and the incidence of UIAS or UIAL were recorded. DATA SYNTHESIS: Comparative meta-analysis was conducted on four cohort studies for comparison of UIAS and UIAL between the stented and nonstented groups. Besides, eleven studies which reported the events of UIAS and UIAL were used for meta-analysis of single proportion. RESULTS: A total of 11 studies were qualified for analysis. Comparative meta-analysis identified that the incidence of UIAS was higher in the stented group than that in the nonstented group, but this did not reach a significant difference (odds ratio [OR]: 1.64; 95% confidence interval [CI]: 0.88-3.05; P = 0.12). Besides, there was no difference in the incidences of UIAL between the stented and the nonstented groups. On meta-analysis of single proportion, the incidence of UIAS was 7% (95% CI: 3%-10%) in the stented group and 3% (95% CI: 1%-6%) in the nonstented group. The UIAL rate was 1% (95% CI, 0%-4%) in stented patients and 2% (95% CI, 1%-4%) in nonstented patients. CONCLUSION: Stenting the ureteroileal anastomosis resulted in a higher incidence of UIAS. There is no evidence to support ureteral stents could prevent the occurrence of UIAL after urinary diversion.

A Novel Use of Modified Tracheostomy Tubes in Preventing External Auditory Canal Stenosis.

BACKGROUND: Postoperative or post-traumatic canal restenosis in patients with external auditory canal (EAC) stenosis is a troublesome complication faced by many ear surgeons following canalplasty or meatoplasty. Many ear prostheses and surgical methods have been introduced to prevent the occurrence of such complication. Our aim in this study is to explore the feasibility of using modified non-fenestrated uncuffed tracheostomy tubes (TT) as postoperative stents after ear canal surgery. METHODS: Canalplasty or meatoplasty was performed under general anesthesia via the posterior auricular transcanal approach. The EAC diameter and length were measured and a non-fenestrated uncuffed TT of suitable size was fitted into the ear canal. The TT was then modified during fitting, to fit onto the concha. Patients were advised on the importance of compliance. The adequacy of the size of the EAC after the surgery was assessed during follow-ups. RESULTS: A total of 3 patients (4 ears) were included in our study. Various sizes of TTs were fitted into their EAC following canalplasty or meatoplasty. All of them showed excellent postoperative outcome on follow up 2 years after the surgery, with no evidence of postoperative EAC stenosis. CONCLUSION: Modified TT stent after canalplasty or meatoplasty is proposed as an excellent alternative in preventing restenosis of EAC in centers with limited resources.

Topical estrogen, testosterone, and vaginal dilator in the prevention of vaginal stenosis after radiotherapy in women with cervical cancer: a randomized clinical trial.

BACKGROUND: We aimed to evaluate the effects of different therapeutic options to prevent the evolution of vaginal stenosis after pelvic radiotherapy in women with cervical cancer. METHODS: open-label randomized clinical trial of 195 women, stage I-IIIB, aged 18-75 years, using topical estrogen (66), topical testosterone (34), water-based intimate lubricant gel (66), and vaginal dilators (29) to assess the incidence and severity of vaginal stenosis after radiotherapy at UNICAMP-Brazil, from January/2013 to May/2018. The main outcome measure was vaginal stenosis assessed using the Common Terminology Criteria for Adverse Events (CTCAE) scale and percental changes in vaginal volume. The women were evaluated at four different times: shortly after the end of radiotherapy, and four, eight, and 12 months after the beginning of the intervention. Statistical analysis was carried out using Symmetry test, Kruskal-Wallis test and multiple regression. RESULTS: the mean age of women was 46.78 (±13.01) years, 61,03% were premenopausal and 73,84% had stage IIB-IIIB tumors. The mean reduction in vaginal volume in the total group was 25.47%, with similar worsening in the four treatment groups with no statistical difference throughout the intervention period. There was worsening of vaginal stenosis evaluated by CTCAE scale after 1 year in all groups (p < 0.01), except for the users of vaginal dilator (p = 0.37). CONCLUSIONS: there was a reduction in vaginal volume in all treatment groups analyzed, with no significant difference between them. However, women who used vaginal dilators had a lower frequency and severity of vaginal stenosis assessed by the CTCAE scale after one year of treatment. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials, RBR-23w5fv . Registered 10 January 2017 - Retrospectively registered.

Major modifications to minimize thoracic esophago-gastric leak and eradicate esophageal stricture after Ivor Lewis esophagectomy.

BACKGROUND: The Ivor Lewis esophagectomy (ILE) remains the procedure of choice for localized middle or lower esophageal carcinoma. Nevertheless, anastomotic leak remains a common complication with rates from 3% to 25% and a stricture rate as high as 40%. The frequency of these complications suggests that the procedure itself may have inherent limitations including the use of potentially ischemic tissue for the esophagogastric anastomosis. We introduce a modified technique that reduces operative steps, preserves blood supply, and uses a modified esophagogastric anastomosis. METHODS: All consecutive patients undergoing ILE with the described modified technique were identified. An esophagram was performed on postoperative day six or seven. To ensure that all cases were identified, anastomotic leaks were defined as any radiographic evidence of contrast extravasation. RESULTS: A total of 110 patients underwent the modified esophagectomy with 2 anastomotic leaks (1.82%) and zero strictures. There was 1 late death but no early deaths (<30 or 90 days) or early re-admissions (<30 days). The average number of risk factors was 2.12, and 98 patients (90%) had at least 1 risk factor in their medical history. CONCLUSIONS: The modifications proposed simplify procedural steps, limit unnecessary dissection and introduce a technique that ends the practice of connecting ischemic tissue. We believe this technique contributes to surgical durability and reduces the rate of postoperative leak and eliminates stricture.

Triangular extension of hinge flaps: A novel technique to resolve stomal stenosis and prevent restenosis in staged buccal mucosal urethroplasty.

OBJECTIVES: To verify the utility of triangular extension of a hinge flap in buccal mucosal staged urethroplasty to resolve stomal stenosis after the first stage and ultimately prevent restenosis. METHODS: A total of 23 patients (triangular extension group) were studied in 2013-2019. In the first stage, buccal mucosa was transplanted, and an extended triangle portion of the mucosa was placed beside the proximal and/or distal stoma that was created when the stricture segment of the urethra was resected. In the second stage, during tubularization of the urethral plate, an incision was made at the stoma to increase the caliber to which the triangular extension was inserted. The procedure was considered successful when a 17-Fr flexible cystoscope passed through the reconstructed urethra at 6 months after the second-stage urethroplasty and no additional surgery or bougie dilation required. The clinical course of the triangular extension group was compared with 24 patients who underwent conventional staged urethroplasty (control group). RESULTS: In total, 20 patients from each group underwent second-stage surgery. No patients in the triangular extension group required additional revision surgery because of stomal stenosis after first-stage surgery, whereas five (20%) control patients did. Urethroplasty was successful in 19 patients (95%) in the triangular extension group and in 19 patients (95%) in the control group. Uroflowmetry after the second-stage surgery indicated that the mean maximum urinary flow rate was 21.5 and 15.8 mL/s after triangular extension and the control procedure, respectively (P = 0.027). CONCLUSIONS: The triangular extension technique reduces the need for revision surgery and prevents postoperative restenosis.

Diagnosis and management of pharyngoesophageal stenosis: A comprehensive approach to prophylactic, endoscopic, and reconstructive treatment options.

BACKGROUND: Pharyngoesophageal stenosis (PES) is a serious complication that substantially impacts functional outcomes and quality of life (QOL) for up to a third of head and neck cancer patients who undergo radiotherapy. Dysphagia is often multifactorial in nature and is a devastating complication of treatment that impacts patients' QOL, general health and overall wellbeing. The authors detail the clinical presentation, risk factors, imaging characteristics, preventive measures, and multimodality treatment options for PES. METHODS: The authors present a comprehensive management algorithm for PES, including treatment by dilation, stenting, spray cryotherapy and dilation, and reconstructive treatment options utilizing different pedicled and free flaps. RESULTS: The authors advocate for a thorough assessment of the extent and degree of pharyngoesophageal involvement of PES to determine the optimal management strategy. CONCLUSIONS: The development of post treatment dysphagia requires appropriate imaging and biopsy, when indicated, to rule out the presence of persistent/recurrent cancer. Multidisciplinary management by a team of physicians well-versed in the range of diagnostic and therapeutic interventions available for PES is critical to its successful management.

Impact of physiologically shaped pancreatic stent for chronic pancreatitis.

Endoscopic pancreatic stenting is used to prevent main pancreatic duct obstruction and relieve painful symptoms of chronic pancreatitis. However, the stent typically needs to be exchanged and the rate of adverse events is high. Few studies have evaluated the effect of stent shape on those outcomes. We evaluated the adverse events, stent patency, and total medical cost within 90 days of patients who received an 8.5 French (Fr) physiologically shaped pancreatic stent by comparing these features with those associated with a conventional straight-type stent for ≥ 90 days. The total stent-related adverse event rate was significantly lower for the physiologically shaped pancreatic stent (physiologically shaped, 6.7% [2/30]; straight-type, 50.6% [44/87]; P < 0.001). Stent occlusion was significantly less frequent (P < 0.001) and the total medical costs were significantly lower (P = 0.002) for the physiologically shaped stent. The stent-related adverse event rate was significantly higher for the 10 Fr straight type stent than for the 8.5 Fr physiologically shaped stent (10 Fr, straight-type vs. 8.5 Fr, physiologically shaped: 36.1% [13/36] vs. 6.7% [2/30]; P = 0.007). In conclusion, a physiologically shaped pancreatic stent was superior to a straight-type stent in terms of the patency rate and medical costs.

Collagen Vitrigel Membrane-Coated Nylon Line Prevents Stenosis After Conization of the Cervix Uteri.

Cervical stenosis is a postoperative complication of conization for uterine cervical malignancy, but a standard method of preventing this complication has yet to be established. Collagen vitrigel is a collagen-based biomaterial that has antifibrotic and epithelization promoting actions. We evaluated the antistenotic effect of an indwelling collagen vitrigel membrane-coated nylon line (CVNL) after cervical conization in rabbits. In one group of rabbits, a CVNL was placed in the cervical canal after conization. In another group, a nylon line without a collagen coating was placed in the cervical canal after conization. The control group underwent cervical conization without placement of a device. The control (conization alone) and nylon (conization plus indwelling nylon line) groups exhibited cervical swelling. Rabbits in the CVNL group (cervical conization plus indwelling CVNL in the xerogel state) had a normal cervical surface. The cervical canal in the control group was enlarged and showed cystic changes attributed to cervical stenosis. The nylon group exhibited a trend toward cervical canal dilatation. In the CVNL group, the cervical canal was normal and did not show cystic dilatation. Fibrosis occurred to a lesser degree in the nylon group than in the control group, and the CVNL group exhibited minimal interstitial fibrosis. The control and nylon groups showed increased numbers of myofibroblasts in the regenerated cervix, but few myofibroblasts were observed in the CVNL group. Abundant collagen type III was observed in regenerated cervical tissue in the control and nylon groups but not in the CVNL group. The number of proliferative mesenchymal cells in the regenerated cervix was lowest in the CVNL group. The expressions of connective tissue growth factor (CTGF, a regulator of fibroblast growth and extracellular matrix secretion), extracellular signal-regulated protein kinases 1 and 2, and c-Jun N-terminal kinase (which are involved in the induction of CTGF by transforming growth factor-ß) were lower in the CVNL group than in the control or nylon groups. This study describes an indwelling CVNL that prevents cervical stenosis and cystic changes after conization. These effects were likely mediated by inhibition of fibrosis, myofibroblast emergence, CTGF expression, and collagen type III deposition in regenerating cervix. Impact statement Collagen vitrigel is a high-density collagen material that promotes epithelization, inhibits fibrosis, and suppresses inflammation in regenerating tissue. We evaluated whether a collagen vitrigel membrane-coated nylon line would prevent cervical stenosis after conization in the rabbit. We found that an indwelling collagen vitrigel membrane-coated nylon line prevented cervical canal stenosis and cystic changes after cervical conization by inhibiting fibrosis, myofibroblast emergence, connective tissue growth factor expression, and collagen type III deposition in the regenerating cervix. Our device has potential as a new method of preventing cervical canal fibrosis and stenosis after conization for cervical cancer.