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Dive into the research topics where Yu Ishii is active.

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Featured researches published by Yu Ishii.


World Journal of Gastroenterology | 2015

0.025-inch vs 0.035-inch guide wires for wire-guided cannulation during endoscopic retrograde cholangiopancreatography: A randomized study.

Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Yoshiki Sato; Tomoyuki Iwata; Tomohiro Nomoto; Akitoshi Ikegami; Hitoshi Yoshida

AIM To compare the clinical outcomes between 0.025-inch and 0.035-inch guide wires (GWs) when used in wire-guided cannulation (WGC). METHODS A single center, randomized study was conducted between April 2011 and March 2013. This study was approved by the Medical Ethics Committee at our hospital. Informed, written consent was obtained from each patient prior to study enrollment. Three hundred and twenty-two patients with a naïve papilla of Vater who underwent endoscopic retrograde cholangiopancreatography (ERCP) for the purpose of selective bile duct cannulation with WGC were enrolled in this study. Fifty-three patients were excluded based on the exclusion criteria, and 269 patients were randomly allocated to two groups by a computer and analyzed: the 0.025-inch GW group (n = 109) and the 0.035-inch GW group (n = 160). The primary endpoint was the success rate of selective bile duct cannulation with WGC. Secondary endpoints were the success rates of the pancreatic GW technique and precutting, selective bile duct cannulation time, ERCP procedure time, the rate of pancreatic duct stent placement, the final success rate of selective bile duct cannulation, and the incidence of post-ERCP pancreatitis (PEP). RESULTS The primary success rates of selective bile duct cannulation with WGC were 80.7% (88/109) and 86.3% (138/160) for the 0.025-inch and the 0.035-inch groups, respectively (P = 0.226). There were no statistically significant differences in the success rates of selective bile duct cannulation using the pancreatic duct GW technique (46.7% vs 52.4% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.884) or in the success rates of selective bile duct cannulation using precutting (66.7% vs 63.6% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.893). The final success rates for selective bile duct cannulation using these procedures were 92.7% (101/109) and 97.5% (156/160) for the 0.025-inch and 0.035-inch groups, respectively (P = 0.113). There were no significant differences in selective bile duct cannulation time (median ± interquartile range: 3.7 ± 13.9 min vs 4.0 ± 11.2 min for the 0.025-inch and 0.035-inch groups, respectively; P = 0.851), ERCP procedure time (median ± interquartile range: 32 ± 29 min vs 30 ± 25 min for the 0.025-inch and 0.035-inch groups, respectively; P = 0.184) or in the rate of pancreatic duct stent placement (14.7% vs 15.6% for the 0.025-inch and 0.035-inch groups, respectively; P = 0.832). The incidence of PEP was 2.8% (3/109) and 2.5% (4/160) for the 0.025-inch and 0.035-inch groups, respectively (P = 0.793). CONCLUSION The thickness of the GW for WGC does not appear to affect either the success rate of selective bile duct cannulation or the incidence of PEP.


World Journal of Clinical Cases | 2017

Feasibility of initial endoscopic common bile duct stone removal in patients with acute cholangitis

Akira Yamamiya; Katsuya Kitamura; Yu Ishii; Yuta Mitsui; Tomohiro Nomoto; Hitoshi Yoshida

AIM To investigate the feasibility of initial endoscopic common bile duct (CBD) stone removal in patients with acute cholangitis (AC). METHODS A single-center, retrospective study was conducted between April 2013 and December 2014 and was approved by the Medical Ethics Committee at our institution. Written informed consent was obtained from each patient prior to the procedure. The cohort comprised 31 AC patients with CBD stones who underwent endoscopic biliary drainage (EBD) for naïve papilla within 48 h after AC onset. We retrospectively divided the participants into two groups: 19 patients with initial endoscopic CBD stone removal (initial group) and 12 patients with delayed endoscopic CBD stone removal (delayed group). We evaluated the feasibility of initial endoscopic CBD stone removal in patients with AC. RESULTS We observed no significant differences between the groups regarding patient characteristics. According to the assessments based on the Tokyo Guidelines, the AC severity of patients with initial endoscopic CBD stone removal was mild to moderate. The use of antithrombotic agents before EBD was less frequent in the initial group than in the delayed group (11% vs 58%, respectively; P = 0.004). All the patients underwent successful endoscopic CBD stone removal and adverse events did not differ significantly between the groups. The number of endoscopic retrograde cholangiopancreatography procedures was significantly lower in the initial group than in the delayed group [median (interquartile range) 1 (1-1) vs 2 (2-2), respectively; P < 0.001]. The length of hospital stay was significantly shorter for the initial group than for the delayed group [10 (9-15) vs 17 (14-20), respectively; P = 0.010]. CONCLUSION Initial endoscopic CBD stone removal in patients with AC may be feasible when AC severity and the use of antithrombotic agents are carefully considered.


Endoscopy International Open | 2017

Side-by-side partially covered self-expandable metal stent placement for malignant hilar biliary obstruction

Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Yuta Mitsui; Tomohiro Nomoto; Hitoshi Yoshida

Background and study aims  This study investigated the feasibility of side-by-side (SBS) partially covered self-expandable metal stent (PCSEMS) placement for unresectable malignant hilar biliary obstruction (MHBO). Patients and methods  We retrospectively analyzed 33 patients from a single center who underwent endoscopic biliary drainage for unresectable MHBO from July 2013 to June 2015. In all patients with bilateral obstruction during complete bilateral intrahepatic cholangiograms, we performed endoscopic SBS placement of a 6-mm diameter PCSEMS using an 8-French delivery system. All patients underwent endoscopic sphincterotomy. Generally, patients with recurrent biliary obstruction (RBO) after stent placement underwent endoscopic reintervention. Our study outcomes included the technical and functional success rates, RBO rate, time to RBO (TRBO), reintervention rate, and incidence of adverse events. Results  Seventeen patients with unresectable MHBO during complete bilateral intrahepatic cholangiograms underwent endoscopic SBS PCSEMS placement (median age, 78 years; men, 9). Lesions were Bismuth types II (n = 10), III (n = 1), and IV (n = 6), including 10 cholangiocarcinomas, 3 gallbladder cancers, and 4 metastatic cancers. In all patients, the PCSEMS was placed across the duodenal papilla. The technical and functional success rates were 100 % and 82 %, respectively. The median procedure time was 43 minutes (interquartile range [IQR]: 36 – 52 minutes). Twelve patients had RBO (71 %), including 9 stent occlusions due to sludge and 3 stent migrations. The median TRBO was 79 days (IQR: 58 – 156 days) during the follow-up period (median 192 days [IQR: 88 – 551 days]). The median TRBO of patients with Bismuth type II lesions was significantly longer than that of patients with Bismuth types III and IV lesions (87 days [IQR: 70 – 244 days] vs. 54 days [IQR: 35 – 100 days]; P  = 0.030). Thirteen patients (76 %) required endoscopic reintervention. Endoscopic stent removal was possible in 6 patients without tumor ingrowth into the uncovered distal part of the stent. One late adverse event (≥ 31 days) occurred (cholangitis). Conclusions  Endoscopic SBS placement of a PCSEMS was feasible in patients with unresectable MHBO. Additionally, reinterventional stent removal was possible in the absence of tumor ingrowth.


World Journal of Gastrointestinal Endoscopy | 2014

Evaluation of diagnostic cytology via endoscopic naso-pancreatic drainage for pancreatic tumor

Tomoyuki Iwata; Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Yoshiki Sato; Tomohiro Nomoto; Akitoshi Ikegami; Hitoshi Yoshida

AIM To evaluate the usefulness of cytology of the pancreatic juice obtained via the endoscopic naso-pancreatic drainage tube (ENPD-C). METHODS ENPD was performed in cases where a diagnosis could not be made other than by using endoscopic retrograde cholangiopancreatography and in cases of pancreatic neoplasms or cystic tumors, including intraductal papillary mucinous neoplasm (IPMN) suspected to have malignant potential. 35 patients (21 males and 14 females) underwent ENPD between January 2007 and June 2013. The pancreatic duct was imaged and the procedure continued in one of ENPD-C or ENPD-C plus brush cytology (ENPD-BC). We checked the cytology result and the final diagnosis. RESULTS The mean patient age was 69 years (range, 48-86 years). ENPD-C was performed in 24 cases and ENPD-C plus brush cytology (ENPD-BC) in 11 cases. The ENPD tube was inserted for an average of 3.5 d. The final diagnosis was confirmed on the basis of the resected specimen in 18 cases and of follow-up findings at least 6 mo after ENPD in the 18 inoperable cases. Malignancy was diagnosed in 21 cases and 14 patients were diagnosed as having a benign condition. The ratios of class V/IV:III:II/I findings were 7:7:7 in malignant cases and 0:3:11 in benign cases. The sensitivity and specificity for all patients were 33.3% and 100%, respectively. The cytology-positive rate was 37.5% (6/16) for pancreatic cancer. For IPMN cases, the sensitivity and specificity were 33% and 100%, respectively. CONCLUSION Sensitivity may be further increased by adding brush cytology. Although we can diagnosis cancer in cases of a positive result, the accuracy of ENPD-C remains unsatisfactory.


Pancreas | 2017

The Prognosis of Severe Acute Pancreatitis Varies According to the Segment Presenting with Low Enhanced Pancreatic Parenchyma on Early Contrast-Enhanced Computed Tomography: A Multicenter Cohort Study

Katsuya Kitamura; Masayasu Horibe; Masamitsu Sanui; Mitsuhito Sasaki; Akira Yamamiya; Yu Ishii; Hitoshi Yoshida; Hirotaka Sawano; Takashi Goto; Tsukasa Ikeura; Tsuyoshi Hamada; Takuya Oda; Hideto Yasuda; Yuki Ogura; Dai Miyazaki; Kaoru Hirose; Nobutaka Chiba; Tetsu Ozaki; Takahiro Yamashita; Toshitaka Koinuma; Taku Oshima; Tomonori Yamamoto; Morihisa Hirota; Yoshinori Azumi; Keiji Nagata; Nobuyuki Saito; Mizuki Sato; Kyohei Miyamoto; Eisuke Iwasaki; Takanori Kanai

Objective The aim of this study was to investigate the outcomes of severe acute pancreatitis (SAP) according to the segment presenting with low enhanced pancreatic parenchyma (LEPP) on early contrast-enhanced computed tomography. Methods This was a post hoc analysis of a multicenter, retrospective study conducted at 44 institutions in Japan. Patients diagnosed as having SAP according to the Japanese Severity Score between January 2009 and December 2013 were included. We compared the effect of LEPP in each segment on mortality. Results A total of 1097 patients were assessed. The numbers of patients with LEPP in the pancreatic head (Ph), body (Pb), or tail (Pt) were 272, 273, and 204 (with some overlaps), respectively. In multivariate analysis, LEPP in Ph and Pt was significantly related to mortality (odds ratio [OR], 1.94; 95% confidence interval [CI], 1.11–3.40 [P < 0.05], for LEPP in Ph; OR, 2.44; 95% CI, 1.27–4.67 [P < 0.05], for LEPP in Pt), but LEPP in Pb was unrelated to mortality (OR, 0.70; 95% CI, 0.35–1.37; P = 0.30). Conclusions Presence of LEPP in Ph and Pt on early contrast-enhanced computed tomography was independently associated with increased mortality in SAP. These patients require close observation to ensure timely and adequate intervention.


Internal Medicine | 2017

Peripancreatic Tuberculous Lymphadenitis Diagnosed via Endoscopic Ultrasound-guided Fine-needle Aspiration and Polymerase Chain Reaction

Jun Arai; Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Tomohiro Nomoto; Tadashi Honma; Hiroo Ishida; Eisuke Shiozawa; Masafumi Takimoto; Hitoshi Yoshida

We performed endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) on a patient presenting with an asymptomatic peripancreatic mass-like lesion. The aspiration cytologic finding was class II. On positron emission tomography-computed tomography (PET-CT), there were hot spots in the left supra-clavicular lymph node and the peripancreatic lesion. A whole biopsy of the left supra-clavicular lymph node revealed tuberculous lymphadenitis. Polymerase chain reaction (PCR) using tissue obtained via EUS-FNA showed that the peripancreatic mass-like lesion was also positive for tuberculosis. We made a diagnosis of peripancreatic tuberculous lymphadenitis. In patients with enlarged lymph nodes, including those in the abdominal area, tuberculous lymphadenitis is a potential diagnosis.


World Journal of Gastrointestinal Endoscopy | 2016

Electrocautery vs non-electrocautery dilation catheters in endoscopic ultrasonography-guided pancreatic fluid collection drainage.

Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Tomohiro Nomoto; Tadashi Honma; Hitoshi Yoshida

AIM To investigate the safety and utility of an electrocautery dilation catheter for endoscopic ultrasonography (EUS)-guided pancreatic fluid collection drainage. METHODS A single-center, exploratory, retrospective study was conducted between August 2010 and August 2014. This study was approved by the Medical Ethics Committee of our institution. Informed, written consent was obtained from each patient prior to the procedure. The subjects included 28 consecutive patients who underwent EUS-guided transmural drainage (EUS-TD) for symptomatic pancreatic and peripancreatic fluid collections (PFCs) by fine needle aspiration using a 19-gauge needle. These patients were retrospectively divided into two groups based on the use of an electrocautery dilation catheter as a fistula dilation device; 15 patients were treated with an electrocautery dilation catheter (electrocautery group), and 13 patients were treated with a non-electrocautery dilation catheter (non-electrocautery group). We evaluated the technical and clinical successes and the adverse events associated with EUS-TD for the treatment of PFCs between the two groups. RESULTS There were no significant differences in age, sex, type, location and diameter of PFCs between the groups. Thirteen patients (87%) in the electrocautery group and 10 patients (77%) in the non-electrocautery group presented with infected PFCs. The technical success rates of EUS-TD for the treatment of PFCs were 100% (15/15) and 100% (13/13) for the electrocautery and the non-electrocautery groups, respectively. The clinical success rates of EUS-TD for the treatment of PFCs were 67% (10/15) and 69% (9/13) for the electrocautery and the non-electrocautery groups, respectively (P = 0.794). The procedure time of EUS-TD for the treatment of PFCs in the electrocautery group was significantly shorter than that of the non-electrocautery group (mean ± SD: 30 ± 12 min vs 52 ± 20 min, P < 0.001). Adverse events associated with EUS-TD for the treatment of PFCs occurred in 0 patients and 1 patient for the electrocautery and the non-electrocautery groups, respectively (P = 0.942). CONCLUSION EUS-TD using an electrocautery dilation catheter as a fistula dilation device for the treatment of symptomatic PFCs appears safe and contributes to a shorter procedure time.


Pediatric Dermatology | 2018

Two cases of intraductal papillary mucinous neoplasm with obstructive jaundice caused by pancreatobiliary fistula

Tomono Usami; Tomohiro Nomoto; Kenichi Konda; Ikuya Sugiura; Yuta Mitsui; Akira Yamamiya; Yu Ishii; Katsuya Kitamura; Hitoshi Yoshida


Gastroenterology | 2018

Mo1228 - Iodine Mapping on Dual Energy CT to Predict Walled-off Necrosis of Acute Pancreatitis

Akira Yamamiya; Katsuya Kitamura; Yu Ishii; Yuta Mitsui; Tomohiro Nomoto; Hitoshi Yoshida


Pediatric Dermatology | 2017

A case of successful endoscopic pancreatic stone removal for pancreatic stones with pancreaticobiliary maljunction

Toshihiko Gocho; Katsuya Kitamura; Akira Yamamiya; Yu Ishii; Kensuke Shinmura; Yu Shimozuma; Tomohiro Nomoto; Tadashi Honma; Hitoshi Yoshida

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