Is endoscopic mucosal resection-precutting superior to conventional methods for removing sessile colorectal polyps?

We reviewed a study that reported a comparative analysis of the effects of endoscopic mucosal resection(EMR)precutting and conventional EMR for removing non-pedunculated,10-20 mm sized colorectal polyps.We identified some statistical deficiencies in this study.In addition,we believe that the differences between the treatments failed to achieve significance,and therefore,further analysis is required.

Endoscopic mucosal resection-precutting vs conventional endoscopic mucosal resection for sessile colorectal polyps sized 10-20 mm

BACKGROUND The optimal method to remove sessile colorectal lesions sized 10-20 mm remains uncertain.Piecemeal and incomplete resection are major limitations in current practice,such as endoscopic mucosal resection(EMR)and cold or hot snare polypectomy.Recently,EMR with circumferential precutting(EMR-P)has emerged as an effective technique,but the quality of current evidence in comparative studies of conventional EMR(CEMR)and EMR-P is limited.AIM To investigate whether EMR-P is superior to CEMR in removing sessile colorectal polyps.METHODS This multicenter randomized controlled trial involved seven medical institutions in China.Patients with colorectal polyps sized 10-20 mm were enrolled and randomly assigned to undergo EMR-P or CEMR.EMR-P was performed following submucosal injection,and a circumferential mucosa incision(precutting)was conducted using a snare tip.Primary outcomes included a comparison of the rates of en bloc and R0 resection,defined as one-piece resection and one-piece resection with histologically assessed clear margins,respectively.RESULTS A total of 110 patients in the EMR-P group and 110 patients in the CEMR group were finally evaluated.In the per-protocol analysis,the proportion of en bloc resections was 94.3%[95%confidence interval(CI):88.2%-97.4%]in the EMR-P group and 86%(95%CI:78.2%-91.3%)in the CEMR group(P=0.041),while subgroup analysis showed that for lesions>15 mm,EMR-P also resulted in a higher en bloc resection rate(92.0%vs 58.8%P=0.029).The proportion of R0 resections was 81.1%(95%CI:72.6%-87.4%)in the EMR-P group and 76.6%(95%CI:68.8%-84.4%)in the CEMR group(P=0.521).The EMR-P group showed a longer median procedure time(6.4 vs 3.0 min;P<0.001).No significant difference was found in the proportion of patients with adverse events(EMR-P:9.1%;CEMR:6.4%;P=0.449).CONCLUSION In this study,EMR-P served as an alternative to CEMR for removing nonpedunculated colorectal polyps sized 10-20 mm,particularly polyps>15 mm in diameter,with higher R0 and en bloc resection rates and without increasing adverse events.However,EMR-P required a relatively longer procedure time than CEMR.Considering its potential benefits for en bloc and R0 resection,EMR-P may be a promising technique in colorectal polyp resection.

Can early precut reduce post-endoscopic retrograde cholangiopancreatography pancreatitis in patients with difficult bile duct cannulation?

BACKGROUND Endoscopic retrograde cholangiopancreatography(ERCP)is associated with a variety of adverse events(AEs).One of the most important AEs is post-ERCP pancreatitis(PEP),which is most common in cases of difficult biliary cannulation.Although the precut technique has been reported as a PEP risk factor,recent studies indicate that early precut could reduce PEP,and that precut itself is not a risk factor.AIM To evaluate the safety of the precut technique,especially in terms of PEP.METHODS We conducted a retrospective study,spanning the period from November 2011 through December 2021.It included 1556 patients,aged≥20 years,who underwent their initial ERCP attempt for biliary disease with a naïve papilla at the Kawasaki University General Medical Center.We compared the PEP risk between the early precut and the delayed precut group.RESULTS The PEP incidence rate did not significantly differ between the precut and nonprecut groups.However,the PEP incidence was significantly lower in the early precut group than the delayed precut group(3.5%vs 10.5%;P=0.02).The PEP incidence in the delayed precut group without pancreatic stent insertion(17.3%)was significantly higher compared to other cases(P<0.01).CONCLUSION Our findings indicate that early precut may reduce PEP incidence.If the precut decision is delayed,a pancreatic stent should be inserted to prevent PEP.

Precut技术在胆胰疾病治疗性内镜下逆行胰胆管造影术中的应用价值

摘要：目的探讨治疗性内镜下逆行胰胆管造影术（endoscopicretrogradecholangiopancreatography，ER—CP）在胆胰系统疾病中的治疗价值。方法对2004年2月～2011年11月的1328例经内镜下逆行胰胆管造影术ERCP治疗的病例资料进行回顾性分析，对经ERCP治疗中插管困难者运用Precut技术（乳头预切开技术，包括乳头弓形刀乳头括约肌预切开术、经胰管弓形刀乳头括约肌预切开术、针状刀乳头括约肌预切开术或针状刀乳头括约肌开窗术辅助插管及取石），使部分ERCP插管困难的病例均取得成功，评价治疗性ERCP在各种胆胰疾病中的应用价值。结果治疗病例中胆管结石最多，占65．13％，其次为恶性胆道梗阻，占18．56％，乳头良性狭窄占9．35％，急性胆源性胰腺炎占8．45％，急性梗阻}生化脓性胆管炎占7．25％，医源性胆道损伤占2．52％，慢性胰腺炎占2．11％，胆道蛔虫占0．26％，其他O．16％。并发症发生率3．12％，其中穿孔3例，死亡1例。结论治疗性ERCP对多种胆胰疾病疗效确切，是一种安全有效的胆胰疾病治疗手段，Precut技术是ERCP插管困难病例达到插管成功的有效、安全的办法，可由有经验的消化内镜医生应用于确实有需要进行治疗性ERCP的病例。

Precut技术在ERCP插管困难患者中的有效应用

目的探讨Precut技术在经内镜逆行胰胆管造影(ERCP)插管困难患者中的有效应用。方法收集胆囊切除术后良性胆管狭窄行治疗性ERCP患者68例,按照就诊顺序随机分为试验组和对照组,各34例。对照组予以双导丝辅助切开术进行治疗,试验组予以经胰管乳头括约肌预切开术(Precut技术)进行治疗。比较两组患者ERCP成功率、术中并发症发生情况、中期临床疗效以及狭窄复发情况。结果试验组ERCP成功率为94.12%,对照组ERCP成功率为67.65%,试验组ERCP成功率高于对照组,差异具有统计学意义(P<0.05)。试验组并发症总发生率52.94%,对照组并发症总发生率20.59%,试验组并发症总发生率高于对照组,差异具有统计学意义(P<0.05)。试验组治疗有效率93.75%,对照组治疗有效率60.87%,试验组治疗后中期临床有效率高于对照组,差异具有统计学意义(P<0.05)。随诊12个月观察患者是否存在狭窄复发,对照组出现7例狭窄复发,狭窄复发率为30.43%,试验组出现3例狭窄复发,狭窄复发率为9.38%,试验组狭窄复发率低于对照组,差异具有统计学意义(P<0.05)。结论 Precut技术可以提高胆管插管成功率,但是术后胰腺炎、高淀粉酶血症等并发症发生率较双导丝辅助切开术高。

Precut技术在ERCP插管困难病例中的作用及安全性研究

目的探讨Precut技术在ERCP插管困难病例中的作用及其安全性。方法回顾性分析1997年9月至2007年12月间进行ERCP诊断与治疗操作中常规插管,包括导丝辅助均无法插入胆管且实施了Precut操作的病例。Precut实施采用的是弓形刀和/或针状刀,Precut方法包括经乳头弓形刀乳头括约肌预切开术、经胰管弓形刀乳头括约肌预切开术、针状刀乳头括约肌预切开术和针状刀乳头括约肌开窗术。所有行Precut后能成功深插管的病例如有必要则改用常规方法将十二指肠乳头开口扩大至理想的大小。结果共有65例因ERCP插管困难而实施了Precut操作,年龄19～78岁,平均53岁。总的成功率为83.1%(54/65)。术后高淀粉酶血症的发生率为46.2%(30/65),轻症急性胰腺炎发生率为3.1%(2/65),经治疗3～5天后均能恢复至正常。未出现术后出血与穿孔并发症。结论Precut技术是ERCP插管困难病例达到插管成功的有效、安全的办法,可由资深的消化内镜医生应用于确实有需要进行治疗性ERCP的病例。

Double guidewire technique vs transpancreatic precut sphincterotomy in difficult biliary cannulation

AIM:To compare the outcomes between doubleguidewire technique(DGT) and transpancreatic precut sphincterotomy(TPS) in patients with difficult biliary cannulation.METHODS:This was a prospective,randomized study conducted in single tertiary referral hospital in Korea.Between January 2005 and September 2010.A total of 71 patients,who bile duct cannulation was not possible and selective pancreatic duct cannulation was achieved,were randomized into DGT(n = 34) and TPS(n = 37) groups.DGT or TPS was done for selective biliary cannulation.We measured the technical success rates of biliary cannulation,median cannulation time,and procedure related complications.RESULTS:The distribution of patients after randomization was balanced,and both groups were comparable in baseline characteristics,except the higher percentage of endoscopic nasobiliary drainage in the DGT group(55.9% vs 13.5%,P < 0.001).Successful cannulation rate and mean cannulation times in DGT and TPS groups were 91.2% vs 91.9% and 14.1 ± 13.2 min vs 15.4 ± 17.9 min,P = 0.732,respectively.There was no significant difference between the two groups.The overall incidence of post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis was 38.2% vs 10.8%,P < 0.011 in the DGT group and the TPS group;post-procedure pancreatitis was significantly higher in the DGT group.But the overall incidence of post-ERCP hyperamylasemia was no significant difference between the two groups;DGT group vs TPS group:14.7% vs 16.2%,P < 1.0.CONCLUSION:When free bile duct cannulation was difficult and selective pancreatic duct cannulation was achieved,DGT and TPS facilitated biliary cannulation and showed similar success rates.However,post-procedure pancreatitis was significantly higher in the DGT group.

Precut sphincterotomy:A reliable salvage for difficult biliary cannulation

Even experienced endoscopists have 90% success in achieving deep biliary cannulation with standard methods. Biliary cannulation may become difficult in 10%-15% of patients with biliary obstruction and pre- cut (access) sphincterotomy is frequently chosen as a rescue treatment in these cases. Generally, precut sphincterotomy ensures a rate of 90%-100% success- ful deep biliary cannulation. The precut technique has been performed as either a fistulotomy with a needle knife sphincterotome or as a transpapillary septotomy with a standard sphincterotome. Both methods have similar efficacy and complication rates when adminis- tered to the proper patient. Although precut sphincter- otomy ensures over 90% success of biliary cannula- tion, it has been characterized as an independent risk factor for pancreatitis. The complications of the precut technique are not limited to pancreatitis. Two more important ones, bleeding and perforation, are also re- ported in some publications as being observed more commonly than during standard sphincterotomy. It is also reported that precut sphincterotomy increases morbidity when performed in patients without dilata- tion of their biliary tract. Nevertheless, precut sphinc- terotomy is a good alternative as a rescue method in the setting of a failed standard cannulation method. This paper discusses the technical details, timing, ef- ficacy and potential complications of precut sphincter- otomy.

Comparison of efficacy and safety of transpancreatic septotomy, needle-knife fistulotomy or both based on biliary cannulation unintentional pancreatic access and papillary morphology

Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce data are available on different precut techniques for difficult biliary cannulation. This study aimed to evaluate the efficacy and safety of transpancreatic septotomy(TPS), needle-knife fistulotomy(NKF) or both based on the presence of unintentional pancreatic access and papillary morphology. Methods: Between March 2008 and December 2016, 157 consecutive patients undergoing precutting for an inaccessible bile duct during ERCP were identified. Precut techniques were chosen depending on repetitive inadvertent pancreatic cannulation and the papillary morphology. We retrospectively assessed the rates of cannulation success and procedure-related complications among three groups, namely TPS, NKF, and TPS followed by NKF. Results: The baseline characteristics of the three groups were comparable. The overall success rate of biliary cannulation reached 98.1%, including 111 of 113(98.2%) with TPS, 35 of 36(97.2%) with NKF and 8 of 8(100%) with NKF following TPS, without significant difference among groups. The incidences of total complications and post-ERCP pancreatitis were 9.6% and 7.6%, respectively. There was a trend towards less frequent post-ERCP pancreatitis after NKF(0%) compared with 11 cases(9.7%) after TPS and one case(12.5%) after NKF following TPS, but not significantly different( P = 0.07). No severe adverse event occurred during this study period. Conclusions: The choice of precut techniques by the presence of unintended pancreatic access and the papillary morphology brought about a high success rate without increasing risk in difficult biliary cannulation.

Effect of precut sphincterotomy on post-endoscopic retrograde cholangiopancreatography pancreatitis:A systematic review and meta-analysis

AIM: To conduct a systemic review and meta-analysis to investigate the role of early precut technique. Multiple randomized controlled trails (RCTs) have reported conflicting results of the early precut sphincterotomy.

Safety and success of precut biliary sphincterotomy: Is it linked to experience or expertise?

AIM： To determine the rates of success and complications of precut biliary sphincterotomy （PBS） based on prior experience and to compare the complication rates between PBS and standard endoscopic sphincterotomy （ES）. METHODS： A retrospective evaluation of prospectively collected non-randomized data at an academic tertiary referral center, The study included all patients in an eight-year period who underwent PBS and ES by a single endoscopist who had no formal training in PBS. The main outcorne measures of the study were success and complications of PBS with a comparison to complications of ES.RESULTS： A total of 2939 endoscopic retrograde chola ngiopancreatographies （ERCPs） were performed during the study period, including 818 （28%） ES and 150 （5%） PBS procedures. Selective biliary cannulation via PBS was successful at the first attempt in 75% of the patients. Cannulation was achieved in an additional 13% of the patients at a subsequent attempt （total 87%）. Complication rate from PBS was 45% higher than ES, but did not differ significantly [7% （10/50） vs 5% （38/818）, P = 0.29]. None of the complications from PBS was severe. A significant trend towards increasing success existed with regard to the endoscopist＇s first attempt at precut （P = 0.0393, Cochran-Armitage exact test for trend, Z = -1.7588）. CONCLUSION： Despite the lack of specific training in this technique, PBS was performed with a high success rate and a complication rate similar to or less than reports from other experienced centers. These results suggest that endoscopic experience and perhaps innate endoscopic skill may play an important role in the outcome of this procedure.

Difficult biliary cannulation: Historical perspective, practical updates, and guide for the endoscopist

Despite improvements in endoscopic technologies and accessories, development of advanced endoscopy fellowship programs, and advances in ancillary imaging techniques, biliary cannulation in endoscopic retrograde cholangiopancreatography(ERCP) can still be unsuccessful in up to 20% of patients, even in referral centers. Once cannulation has been deemed to be difficult, the risk of post-ERCP pancreatitis and technical failure inherently increases. A number of factors, including endoscopist experience and patient anatomy, have been associated with difficult biliary cannulation, but predicting a case of difficult cannulation a priori is often not possible. Numerous techniques such as pancreatic guidewire and stenting, early pre-cut, and rendezvous may be employed when standard approaches fail. Data regarding the rate of success and adverse events of these techniques have been variable, though most studies suggest that pancreatic duct stenting generally reduces the rate of post-ERCP pancreatitis in instances of difficult biliary cannulation. Here we provide a review on difficult biliary cannulation and discuss how the choice of which techniques to employ and how to best employ them should be individualized and take into account the skill of the endoscopist, the disorder being treated, the anatomy of the patient, and the available biomedical literature.

Study on magnetic memory signals of medium carbon steel specimens with surface crack precut during loading process

Static tensile test and tensile-tensile fatigue test of medium carbon steel sheet specimens with surface crack precut were performed on MTS810 hydraulic testing machine to clear the meaning of the point of Hp(y) value zero. Magnetic memory signals were measured during the test process. The results show that only one point of Hp(y) zero value exists in all measured magnetic signal curves during the loading process, which should be a sign of intersection of positive-negative magnetic poles after magnetic ordered state appears and does not indicate the position of surface crack precut. The analysis shows that the surface crack precut can not interrupt the magnetic ordered state occurred during the test completely, hence its Hp(y) value is not zero. However, the crack extending to a penetrated defect at the instant of specimen′s fracture leads to the discontinuance of magnetic ordered state.

Precut技术在ERCP插管困难患者中的应用研究

目的探讨经胰管乳头括约肌预切开术(Precut术)在经内镜逆行胰胆管造影(ERCP)插管困难患者中的应用效果。方法选取2016年3月～2018年2月本院收治的86例ERCP插管困难患者,依照治疗方式的不同将其分为对照组(n=43)与观察组(n=43),对照组施以双导丝辅助切开术治疗,观察组施以Precut术治疗,观察两组患者ERCP成功率、并发症发生情况、治疗后中期疗效与狭窄复发情况。结果观察组的ERCP成功率、总有效率与并发症发生率明显高于对照组,差异有统计学意义(P <0.05);观察组的复发率明显低于对照组,差异有统计学意义(P <0.05)。结论 Precut技术在ERCP插管困难患者中的应用具有显著效果,不仅能够提升ERCP成功率与治疗后中期疗效,同时能够有效的降低狭窄复发率,具有较高的临床价值。

Repeat endoscopic retrograde cholangiopancreaticography after failed initial precut sphincterotomy for biliary cannulation

AIM: To investigate the outcome of repeating endoscopic retrograde cholangiopancreaticography (ERCP) after initially failed precut sphincterotomy to achieve biliary cannulation.

Management of difficult bile duct cannulation in ERCP

In Encoscopic Retrograde Cholangiopancreatography(ERCP),the main concern is to gain access into the bile duct while avoiding the pancreatic duct because of the risk of post-ERCP pancreatitis.Diffi cult cannulation is defined as a situation where the endoscopist,using his/her regularly used cannulation technique,fails within a certain time limit or after a certain number of unsuccessful attempts.Different methods have been developed to manage diffi cult cannulation.The most common solution is to perform a precut papillotomy either with a needle knife or with a sphincterotome with or without a guide wire.This review describes different methods to overcome cases of difficult cannulation.We will discuss the success rate and complication rates associated with different methods of reaching the biliary tract.

Failed biliary cannulation: Clinical and technical outcomes after tertiary referral endoscopic retrograde cholangiopancreatography

AIM: Prospective evaluation of repeat endoscopic retrograde cholangiopancreatography (ERCP) for failed Schutz grade 1 biliary cannulation in a high-volume center. METHODS: Prospective intention-to-treat analysis of patients referred for biliary cannulation following recent unsuccessful ERCP. RESULTS: Fifty-one patients (35 female; mean age: 62.5 years; age range: 40-87 years) with previous failed biliary cannulation were referred for repeat ERCP. The indication for ERCP was primarily choledocholithiasis (45%) or pancreatic malignancy (18%). Successful biliary can- nulation was 100%. The precut needle knife sphincterotomy (NKS) rate was 27.4%. Complications occurred in 3.9% (post-ERCP pancreatitis). An identif iable reason for initial unsuccessful biliary cannulation was present in 55% of cases. Compared to a cohort of 940 nave pa-pilla patients (female 61%; mean age: 59.9 years; age range: 18-94 years) who required sphincterotomy over the same time period, there was no statistical difference in the cannulation success rate (100% vs 98%) or postERCP pancreatitis (3.1% vs 3.9%). Precut NKS use was more frequent (27.4% vs 12.7%) (P = 0.017). CONCLUSION: Referral to a high-volume center following unsuccessful ERCP is associated with high technical success, with a favorable complication rate, compared to routine ERCP procedures.

Escalating complexity of endoscopic retrograde cholangiopancreatography over the last decade with increasing reliance on advanced cannulation techniques

BACKGROUND At our academic tertiary care medical center, we have noted patients referred for endoscopic retrograde cholangiopancreatography(ERCP) who increasingly require advanced cannulation techniques. This trend is noted despite increased endoscopist experience and annual ERCP volume over the same period.AIM To evaluate this phenomenon of perceived escalation in complexity of cannulation at ERCP and assessed potential underlying factors.METHODS Demographic/clinical variables and records of ERCP patients at the beginning(2008), middle(2013) and end(2018) of the last decade were reviewed retrospectively. Cannulation approaches were classified as "standard" or "advanced" and duodenoscope position was labeled as "standard"(short position) or "non-standard"(e.g., long, semi-long).RESULTS Patients undergoing ERCP were older in 2018 compared to 2008(69.7 ± 15.2 years vs 55.1 ± 14.7, P < 0.05). Increased ampullary distortion and peri-ampullary diverticula were noted in 2018(P < 0.001). ERCPs were increasingly performed with a non-standard duodenoscope position, from 2.2%(2008) to 5.6%(2013) and 16.1%(2018)(P < 0.001). Utilization of more than one advanced cannulation technique for a given ERCP increased from 0.7%(2008) to 0.9%(2013) to 6.6%(2018)(P < 0.001). Primary mass size > 4 cm, pancreatic uncinate mass, and bilirubin > 10 mg/d L predicted use of advanced cannulation techniques(P < 0.03 for each).CONCLUSION Complexity of cannulation at ERCP has sharply increased over the past 5 years, with an increased proportion of elderly patients and those with malignancy requiring advanced cannulation approaches. These data suggest that complexity of cannulation at ERCP may be predicted based on patient/ampulla characteristics. This may inform selection of experienced, high-volume endoscopists to perform these complex procedures.

预切开术(Precut)是困难胆管插管的一有效和安全的方法?

内镜下十二指肠乳头切开术(EPT)的开始使胆道疾病的治疗有了根本性的转变。内镜下经乳头取石已不仅限于高危外科手术患者。如今EPT已被广泛地使用双腔或三腔乳头切开刀导线进行引导。

Precut技术对高龄乳头嵌顿性胆结石患者的疗效及安全性研究

目的探讨Precut技术对高龄乳头嵌顿性胆结石患者的治疗效果及安全性的研究。方法总结回顾分析2007年1月至2009年12月38例高龄患者ERCP术后确诊乳头嵌顿性胆总管结石的患者，对经内镜逆行胰胆管造影术（ERCP）治疗中插管困难者运用Precut技术辅助插管及取石，行乳头括约肌切开后，结石常能自行脱出。结果38例高龄ERCP插管困难患者，行Precut技术取石成功率100％，无死亡病例，其中弓形刀切开8例，针状刀切开10例，两刀联合切开20例。结论治疗性ERCP是乳头嵌顿性胆结石患者一种安全有效的治疗手段，尤其对高龄无法耐受外科手术的患者，这类患者常伴插管及取石困难，Precut技术无疑是取石成功的关键。