Pancreatic guidewire placement for achieving selective biliary cannulation during endoscopic retrograde cholangio-pancreatography

AIM: To investigate the frequency and risk factors for acute pancreatitis after pancreatic guidewire placement (P-GW) in achieving cannulation of the bile duct during endoscopic retrograde cholangio-pancreatography (ERCP). METHODS: P-GW was performed in 113 patients in whom cannulation of the bile duct was difficult. The success rate of biliary cannulation, the frequency and risk factors of post-ERCP pancreatitis, and the frequency of spontaneous migration of the pancreatic duct stent were investigated. RESULTS: Selective biliary cannulation with P-GW was achieved in 73% of the patients. Post-ERCP pancreatitis occurred in 12% (14 patients: mild, 13; moderate, 1). Prophylactic pancreatic stenting was attempted in 59% of the patients. Of the 64 patients who successfully underwent stent placement, three developed mild pancreatitis (4.7%). Of the 49 patients without stent placement, 11 developed pancreatitis (22%: mild, 10; moderate, 1). Of the five patients in whom stent placement was unsuccessful, two developed mild pancreatitis. Univariate and multivariate analyses revealed no pancreatic stenting to be the only significant risk factor for pancreatitis. Spontaneous migration of the stent was observed within two weeks in 92% of the patients who had undergone pancreatic duct stenting.CONCLUSION: P-GW is useful for achieving selective biliary cannulation. Pancreatic duct stenting after P-GW can reduce the incidence of post-ERCP pancreatitis, which requires evaluation by means of prospective randomized controlled trials.

Relationship between post-ERCP pancreatitis and the change of serum amylase level after the procedure

AIM: To clarify the relationship between the change of serum amylase level and post-ERCP pancreatitis. METHODS: Between January 1999 and December 2002, 1291 ERCP-related procedures were performed. Serum amylase concentrations were measured before the procedure and 3, 6, and 24 h afterward. The frequency and severity of post-ERCP pancreatitis and the relationship between these phenomena and the change in amylase level were estimated. RESULTS: Post-ERCP pancreatitis occurred in 47 patients (3.6%). Pancreatitis occurred in 1% of patients with normal amylase levels 3 h after ERCP, and in 1%, 5%, 20%, 31% and 39% of patients with amylase levels elevated 1-2 times, 2-3 times, 3-5 times, 5-10 times and over 10 times the upper normal limit at 3 h after ERCP, respectively (level < 2 times vs ≥ 2 times, P < 0.001). Of the 143 patients with levels higher than the normal limit at 3 h after ERCP followed by elevation at 6 h, pancreatitis occurred in 26%. In contrast, pancreatitis occurred in 9% of 45 patients with a level higher than two times the normal limit at 3 h after ERCP followed by a decrease at 6 h (26% vs 9%, P < 0.05). CONCLUSION: Post-ERCP pancreatitis is frequently associated with an increase in serum amylase level greater than twice the normal limit at 3 h after ERCP with an elevation at 6 h. A decrease in amylase level at 6 h after ERCP suggests the unlikelihood of development of post-ERCP pancreatitis.

Pancreaticobiliary reflux as a high-risk factor for biliary malignancy:Clinical features and diagnostic advancements

Pancreaticobiliary junction is composed of complex structure with which biliary duct and pancreatic duct assemble and go out into the ampulla of Vater during duodenum wall surrounding the sphincter of Oddi.Although the sphincter of Oddi functionally prevents the reflux of pancreatic juice,pancreaticobiliary reflux(PBR) occurs when function of the sphincter of Oddi halt.The anatomically abnormal junction is termed pancreaticobiliary maljunction(PBM) and is characterized by pancreatic and bile ducts joining outside of the duodenal wall.PBM is an important anatomical finding because many studies have revealed that biliary malignancies are related due to the carcinogenetic effect of the pancreatic back flow on the biliary mucosa.On the other hand,several studies have been published on the reflux of pancreatic juice into the bile duct without morphological PBM,and the correlation of such cases with biliary diseases,especially biliary malignancies,is drawing considerable attention.Although it has long been possible to diagnose PBM by various imaging modalities,PBR without PBM has remained difficult to assess.Therefore,the pathological features of PBR without PBM have not been yet fully elucidated.Lately,a new method of diagnosing PBR without PBM has appeared,and the features of PBR without PBM should soon be better understood.

Magnetic resonance evaluations of biliary malignancy and condition at high-risk for biliary malignancy:Current status

Tumors of the biliary tree are relatively rare; but their incidence is rising worldwide. There are several known risk factors for bile duct cancers, and these are seem to be associated with chronic inflammation of the biliary epithelium. Herein, 2 risk factors have been discussed, primary sclerosing cholangitis and reflux of pancreatic juice into the bile duct, as seen in such as an abnor- mal union of the pancreatic-biliary junction because magnetic resonance imaging(MRI) is used widely and effectively in the diagnosis of these diseases. When biliary disease is suspected, MRI can often help dif- ferentiate between benignity and malignancy, stage tumors, select surgical candidates and guide surgical planning. MRI has many advantages over other modali- ties. Therefore, MRI is a reliable noninvasive imaging tool for diagnosis and pre-surgical evaluation of bile duct tumors. Nowadays remarkable technical advances in magnetic resonance technology have expanded the clinical applications of MRI in case of biliary diseases. In this article, it is also discussed how recent develop- ments in MRI contributes to the diagnosis of the bile duct cancer and the evaluation of patients with risk fac- tors affecting bile duct cancer.

Histological changes at an endosonography-guided biliary drainage site:A case report

Endosonography-guided biliary drainage (ESBD) is a new method enabling internal drainage of an obstructed bile duct. However,the histological conditions associated with fistula development via the duodenum to the bile duct have not been reported. We performed ESBD 14 d preoperatively in a patient with an ampullary carcinoma and histologically confirmed changes in and around the fistula. The female patient developed no complications relevant to ESBD. Levels of serum bilirubin and hepatobiliary enzymes declined quickly,and pancreatoduodenectomy was carried out uneventfully. The resected specimen was sliced and stained with hematoxylin-eosin. Histological evaluation of the puncture site in the duodenum and bile-duct wall,and the sinus tract revealed no hematoma,bile leakage,or abscess in or around the sinus tract. Little sign of granulation,fibrosis,and inflammatory cell infiltration was observed. Although further large-scale confirmatory studies are needed,the findings here may encourage more active use of ESBD as a substitute for percutaneous transhepatic drainage in cases with failed/difficult endoscopic biliary stenting.

腹腔镜胆囊切除术前64层CT对胆囊动脉与胆囊管的评价

目的回顾性评价64层CT对Calot三角区胆囊动脉与胆囊管的术前评估。方法学院医学伦理委员会批准免除通知病人签署知情同意书。共245例病人（男133例，女112例）进行了检查，其中包括随后行胆囊切除术的48例病人。由2位独立的医生对CT影像进行评价，包括横断面、冠状面与矢状面多平面重组与三维容积再现影像。同时评价胆囊动脉与Calot三角的关系。Calot三角区的界限为肝脏下面，总肝管与胆囊管之间。根据胆囊动脉的起源与Calot三角区的走行对每例病人进行分类，计算其百分比与可信区间，

Carbon dioxide insufflation in esophageal endoscopic submucosal dissection reduces mediastinal emphysema: A randomized, double-blind, controlled trial

AIM To assess the efficacy of CO2 insufflation for reduction of mediastinal emphysema(ME) immediately after endoscopic submucosal dissection(ESD).METHODS A total of 46 patients who were to undergo esophageal ESD were randomly assigned to receive either CO2 insufflation(CO2 group, n = 24) or air insufflation(Air group, n = 22). Computed tomography(CT) was carried out immediately after ESD and the next morning. Pain and abdominal distention were chronologically recorded using a 100-mm visual analogue scale(VAS). The volume of residual gas in the digestive tract was measured using CT imaging. RESULTS The incidence of ME immediately after ESD in the CO2 group was significantly lower than that in the Air group(17% vs 55%, P = 0.012). The incidence of ME the next morning was 8.3% vs 32% respectively(P= 0.066). There were no differences in pain scores or distention scores at any post-procedure time points. The volume of residual gas in the digestive tract immediately after ESD was significantly smaller in the CO2 group than that in the Air group(808 m L vs 1173 m L, P = 0.013).CONCLUSION CO2 insufflation during esophageal ESD significantly reduced postprocedural ME. CO2 insufflation also reduced the volume of residual gas in the digestive tract immediately after ESD, but not the VAS scores of pain and distention.

Diffusion-weighted MRI in abdominal oncology:Clinical applications

Diffusion-weighted magnetic resonance imaging(DWI) provides image contrast that is different from that obtained by conventional magnetic resonance techniques.Although previously,DWI has been used to evaluate various diseases of the central nervous system,several technical advances have expanded the clinical applications of DWI beyond the central nervous system.As a result,many reports have been published on the use of DWI in abdominal diseases.Particularly,abdominal DWI has now being focused on evaluation of patients with abdominal cancer.DWI can be used for pretreatment tumor detection,characterization including predicting tumor response to therapy,monitoring tumor response during therapy,and follow-up study after treatment to detect possible tumor recurrence.

高b值扩散加权磁共振成像胆囊癌检出的初步研究与研究结果

本研究旨在回顾性评价高b值扩散加权成像（DWI）对于胆囊癌的检出价值。15例胆囊癌病人和14例其他病人纳入研究。所有病人均进行了DWI检查，由2位放射科医师评价影像。计算受试者工作特征曲线的曲线下面积（AUC）、测量得到的表观扩散系数（ADC）、敏感度和特异度。

Endoscopic biliary drainage for patients with unresectable pancreatic cancer with obstructive jaundice who are to undergo gemcitabine chemotherapy

AIM: To assess optimum endoscopic biliary drainage (EBD) in cases with unresectable pancreatic cancer in the era of gemcitabine (GEM). METHODS: Thirty patients with unresectable pancreatic cancer, who presented with jaundice and underwent chemotherapy using GEM after EBD were included in this study (GEM group). Fifteen cases with the same clinical manifestation and stage of pancreatic cancer treated with EBD alone were also included as controls. A covered metallic stent (CMS) or a plastic stent (PS) was used for EBD. The mean survival time (MST) in each group, risk factors of survival time, type of stent used and associated survival time, occlusion rate of stent, patency period of stent, and risk factors of stent occlusion were evaluated. RESULTS: MST in the GEM group was longer than that in the control (9.9 mo vs 6.2 mo). In the GEM group, the survival time was not different between those who underwent metallic stenting and those who underwent plastic stenting. Stent occlusion occurred in 60% of the PS group and 7% of the CMS group. The median stent patency in the PS-GEM group and the CMS-GEM group was 5 mo and 7.5 mo, respectively. Use of a PS was the only risk factor of stent occlusion. CONCLUSION: A CMS is recommended in cases presenting with jaundice due to unresectable pancreatic cancer, since the use of a CMS makes it possible to continue chemotherapy using GEM without repetition of stent replacement.

Efficacy of a newly developed dilator for endoscopic ultrasound-guided biliary drainage

To evaluate the efficacy of a newly developed dilator for endoscopic ultrasound (EUS)-guided drainage (ES Dilator). METHODSFourteen consecutive patients who had undergone EUS-guided choledochoduodenostomy (EUS-CDS) with the ES Dilator were identified from a prospectively maintained database and enrolled in the study group. Fourteen other patients who had undergone EUS-CDS without the dilator just prior to its introduction were analyzed as the control group. A historical cohort study was carried out comparing the two groups. The main outcome measurement was the procedure time. The technical success rate and early AE rate were also compared between the two groups. RESULTSThere were no significant differences in age, sex and etiology of biliary obstruction. The utilization rate of a plastic stent was higher in the control group (36% vs 0%). The technical success rate was 100% in both groups. The mean procedure time was significantly shorter in the study group than in the control group (27 ± 7 min vs 44 ± 26 min, P = 0.026). Additionally, there were no patients who required more than 40 min for the procedure in the study group. Early adverse events occurred in 29% (4/14) of the control group whereas none in the study group. The adverse events in all 4 patients was bile peritonitis, including pan-peritonitis in one patient. All patients recovered with conservative treatment by medication. CONCLUSIONThe newly developed dilator was found to be useful for shortening procedure time and would prevent adverse events related to bile leakage in EUS-CDS.

胰腺导管乳头状黏液瘤的进展:超声内镜随访病例的分析

Background: We investigated the mode of progression of intraductal papillary- mucinous neoplasm of the pancreas (IPMN) in patients who underwent follow- up in order to elucidate the characteristics of malignancy and to establish an effective treatment strategy. Methods: Fifty- one patients with IPMN (branch- duct type, 47; main- duct type, 4)who had undergone follow- up study by endoscopic ultrasonography (EUS)were included (mean follow- up duration, 41.0 ± 32.3 months; average number of EUS examinations performed during follow- up, 4.4). Chronological changes in EUS findings and histological findings of resected specimens were evaluated. Results: Of the patients with the branch- duct type, only 2% showed enlargement of the dilated branches. In the main- duct- type group, an increase in size of the main pancreatic duct (MPD) was observed in 75% of the patients. In 14 patients with papillary protrusions, an increase in size and lateral spreadwas observed in 71% and 43% , respectively. No patients developed invasive cancer. In 15 patients who had thick septum- like structures (TSS), the development of papillary protrusions and that of invasive cancer were observed in 53% and 13% , respectively. Twenty- nine patients who had thin septum- like structures showed no change. Two patients with dense multilocular large cysts and TSS developed invasive cancer without change in the cystic lesions. One patient developed carcinoma with multifocal stromal invasion. Conclusions: Patients with branch- duct type IPMNs without papillary protrusions or TSS are not immediate candidates for surgery. Those who have small papillary protrusions have a benign course. It is recommended that patients with the large branch- duct type with TSS should undergo surgery. Attention should be paid to the entire pancreas when performing follow- up examinations in patients with branch- duct type IPMN, as invasive ductal adenocarcinoma can develop at a site in the pancreas different from that of the IPMN.