Wataru Sumida
Nagoya University
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Featured researches published by Wataru Sumida.
Journal of Pediatric Gastroenterology and Nutrition | 2008
Yasuyuki Ono; Kenitiro Kaneko; Takahisa Tainaka; Wataru Sumida; Hisami Ando
Objectives: Pancreaticobiliary maljunction without bile duct dilatation (nondilated type) is rare in children, and its definition remains unclear. There is controversy over treatment between pediatric and adult patients. We reevaluated our previous definition of the nondilated type in children (common bile duct diameter ≤6 mm on cholangiography). Patients and Methods: Of 150 children with pancreaticobiliary maljunction, 14 fulfilled the definition of the nondilated type. Clinical and cholangiographic findings were reviewed and compared with cholangiograms of 17 children without biliary diseases (controls). The age-related normal range of the choledochal diameter was defined in combination with previous data. Results: All of the patients had symptoms and signs similar to those of choledochal cysts. Cholangiographic features of choledochal cysts were detected in all of the patients (dilated common channel, 8; distal bile duct stenosis, 5; dilated cystic duct, 4; filling defect in the common channel, 8). The choledochal diameter in control children increased with age. Only 4 patients (29%) had a choledochal caliber within the normal range. Conclusions: Most pediatric cases reported as the nondilated type are slightly dilated (forme fruste) choledochal cysts and differ from the nondilated type seen in adults. The nondilated type in children should be defined on the basis of the age-related choledochal diameter.
Journal of Pediatric Surgery | 2008
Kenitiro Kaneko; Yasuyuki Ono; Takahisa Tainaka; Wataru Sumida; Hisami Ando
Symptoms of choledochal cysts are caused by protein plugs, which clog up in the long common channel and increase pancreaticobiliary ductal pressure. We report that fatty calcium acid stones/debris are another previously unreported cause of obstructive symptoms in 2 cases with choledochal cyst.
Pediatric Surgery International | 2008
Takahisa Tainaka; Kenitiro Kaneko; Shigeo Nakamura; Yasuyuki Ono; Wataru Sumida; Hisami Ando
Bile lakes develop after hepatic portoenterostomy in some patients with biliary atresia, and have been regarded as an indication of poor prognosis. We reported that bile lakes have no epithelium of the bile duct on their wall, and are surrounded by bile ducts; however, the mechanism of bile lake formation is little known. We investigated histologically how bile ducts are formed using whole removed liver, and the characteristics of bile ducts around bile lakes. From April 1980 to July 2006, we encountered 84 patients with biliary atresia. Bile lakes were analyzed histologically in 11 patients who underwent liver transplantation in our hospital. Bile lakes had a fibrotic cyst wall and lacked epithelia. In most cases, bile stasis, calculi formation, damaged bile ducts, and invasion of inflammatory cells were observed around the bile lakes. Bile ducts around bile lakes were not stained by CD56, but bile ducts around liver lobuli were stained by CD56. The present study speculates that bile lakes would arise from original bile ducts, which are damaged, and fuse together after calculi are formed in bile ducts.
Journal of Pediatric Surgery | 2011
Yoshio Watanabe; Hidemi Takasu; Wataru Sumida
BACKGROUND/PURPOSE Excessively long segment of congenital hypoganglionosis is rare, and therapeutic strategies to treat this disorder are not well established. The purpose of this study is to describe the significance of management in the neonatal and early infancy period. PATIENTS AND METHODS Four patients (aged 1-4 years) with hypoganglionosis were selected for this study, of which 3 were treated at our hospital. In the initial treatment of 3 cases, an intraoperative pathological diagnosis was made on the basis of findings from simultaneous biopsies taken from the jejunum and sigmoid colon. Retrospective reviews of these patients were performed. RESULTS Initial double-barrel jejunostomy at less than 50 cm from the ligament of Treitz allowed patients to start oral nutrition within a week following surgery. Subsequent refashioning of the initial jejunostomy to the Bishop-Koop type was performed at 3 to 6 months of age. Intravenous hyperalimentation was required to meet less than 50% of nutritional requirements, and patients were able to maintain their body weight within 1.5 SD of the normal mean body weight. Liver function test results were also within normal limits in the 3 patients treated at our hospital. CONCLUSION Early diagnosis and treatment may help improve the management of patients in the early stages of hypoganglionosis.
Journal of Pediatric Gastroenterology and Nutrition | 2007
Takahisa Tainaka; Kenitiro Kaneko; Takahiko Seo; Yasuyuki Ono; Wataru Sumida; Hisami Ando
Background: Intrahepatic cystic lesions develop after hepatic portoenterostomy in some patients with biliary atresia and have been regarded as an indication of poor prognosis; however, there is confusion about the terminology and concepts of the lesions. We investigated whether the cystic lesions constituted a single entity. Patients and Methods: From 1980 to 2005, we encountered 80 patients with biliary atresia. Abdominal ultrasonography disclosed intrahepatic cystic lesions in 20 (25%) patients after hepatic portoenterostomy. The cystic lesions were analyzed morphologically with radiologic imaging studies and histologically in 13 patients who underwent liver transplantation. Results: Fifteen patients had solitary simple cystic lesions, and 5 patients had multiple continuous oval or beaded lesions. Solitary lesions had a fibrotic cyst wall and lacked epithelia. Continuous lesions had a cyst wall covered with biliary epithelia. Thirteen patients with solitary cysts died or required liver transplantation. In 2 patients with continuous lesions, surgical reboring of the porta hepatis could eliminate cystic lesions and jaundice. Conclusions: Intrahepatic cystic lesions include 2 different conditions. Solitary cysts are retention pseudocysts, which should be referred to as a bile lake, and are associated with poor prognosis. Continuous beaded cysts are dilated bile ducts, which may be reversed. This distinction is important when considering the treatment strategy.
Transplantation Proceedings | 2008
Yasuyuki Ono; Yoshinori Ito; Kenitiro Kaneko; Y. Shibata-Watanabe; Takahisa Tainaka; Wataru Sumida; Taro Nakamura; Hideya Kamei; Tetsuya Kiuchi; Hisami Ando; Hiroshi Kimura
Cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus-6 (HHV-6) cause symptomatic diseases in liver transplant recipients. The loads of these viruses, the associations between viral DNAemia, serologic status, and acute rejection reactions were investigated in a group of 17 juvenile and 17 adult recipients of living donor liver transplantation (LDLT) for a median of 8 weeks posttransplantation. At least 1 plasma sample from 15/34 (44.1%) patients was positive for CMV DNA. For most of the CMV-positive patients, the CMV DNA appeared in the second week of LDLT, and disappeared by the eighth week. A minimum of 200 EBV DNA copies/mug peripheral blood mononuclear cell DNA (defined as positive for EBV) was detected in 5/34 (14.7%) patients, and the number of EBV-positive children was significantly greater than the number of EBV-positive adults. In most of the EBV-positive patients, the EBV loads increased after 4 weeks posttransplantation. Plasma HHV-6 was detected in 7/34 (20.6%) patients. HHV-6 DNA appeared for a short period from the second week of LDLT. In addition, 8 of the 19 virus-positive recipients carried 2 viruses, with the combination of CMV and HHV-6 being the most frequent. Serologic status seemed to be an important factor for all 3 viral infections. The rate of acute cellular rejection was not significantly higher in the CMV-, EBV-, or HHV-6-positive groups. Simultaneous monitoring for 3 herpesviruses revealed the impact of these viruses on LDLT recipients.
Pediatric Surgery International | 2013
Yoshio Watanabe; Hidemi Takasu; Wataru Sumida; Kensaku Mori
PurposeThe distribution of sphincter muscle complex in anorectal malformation (ARM) needs to be investigated on a case-by-case basis. This study was undertaken to demonstrate the differences in the anal sphincter muscles between patients with the same type of ARM. Computed tomography (CT) data from cases of high- and intermediate-type male patients with ARM were reviewed using three-dimensional (3D) image analysis.Materials and methodsTwenty-seven male patients with ARM (18 high and 9 intermediate) before anorectoplasty were assessed using multidetector-row helical CT (MRH-CT). A 3D reconstruction was made using volume rendering method. The multi-dimensional sections of the 3D reconstructed images of the pelvic muscles were then analyzed and compared with schematic drawings from the literature.ResultsThe sphincters in the high and intermediate types of ARM could be divided into five groups. In 13 out of 18 cases in the high type and 7 out of 9 cases in the intermediate type, images of the sphincter muscles appeared different from schematic drawings appearing in the literature.ConclusionIn both high and intermediate types of ARM, more than 2/3 of cases demonstrated unexpectedly displaced and deformed hypoplastic sphincters. Therefore, we recommend that variations in anal sphincter should be investigated on an individual basis prior to surgery.
Journal of Pediatric Surgery | 2017
Yujiro Tanaka; Takahisa Tainaka; Wataru Sumida; Chiyoe Shirota; Akinari Hinoki; Naruhiko Murase; Kazuo Oshima; Ryo Shirotsuki; Kosuke Chiba; Hiroo Uchida
BACKGROUND/PURPOSE We previously found that many patients who developed hepatolithiasis after choledochal cyst excisions had intrahepatic bile duct stenosis (IHBDS). In 1992, we started resection of the membrane or septum which was found at the site of IHBDS during choledochal cyst excisions. Since intrahepatic stones usually take years to form, the efficacy of this procedure has not been proved. METHODS The records of patients who had IHBDS-causing membrane or septum and underwent choledochal cyst excision with Roux-Y hepaticojejunostomy between January 1979 and December 2006 were retrospectively analyzed. The patients who underwent surgical treatment for IHBDS-causing membrane or septum were compared with those who did not undergo the procedure. RESULTS Sixty-nine patients met the criteria, and seven patients who were followed up for less than 5years were excluded from the study. Thirty-three patients underwent surgical treatment for IHBDS, and three of them developed intrahepatic stones. Meanwhile, 10 of 29 patients who did not undergo the procedure developed intrahepatic stones. A statistically significant difference in intrahepatic stone formation was observed between the two groups in a log-rank test (P=0.016). CONCLUSIONS Meticulous probing and excision of the IHBDS-causing membrane or septum are effective for preventing hepatolithiasis after choledochal cyst excisions. TYPE OF STUDY Retrospective Comparative Study. LEVEL OF EVIDENCE Level III.
American Journal of Case Reports | 2017
Chiyoe Shirota; Akinari Hinoki; Masataka Takahashi; Yujiro Tanaka; Takahisa Tainaka; Wataru Sumida; Naruhiko Murase; Kazuo Oshima; Ryo Shirotsuki; Kosuke Chiba; Yuji Morimoto; Hiroo Uchida
Patient: Male, 15 Final Diagnosis: Lymphatic malformations Symptoms: Abdominal pain Medication: — Clinical Procedure: Navigation surgery Specialty: Surgery Objective: Unusual or unexpected effect of treatment Background: We used indocyanine green (ICG) fluorescence imaging to completely resect lymphatic malformations (LMs). This is the first report of navigation surgery utilizing ICG fluorescence imaging for resection of LMs. Case Report: A 15-year-old boy was diagnosed with LMs in the abdominal wall. The extent of the tumor was determined by an ultrasound, and ICG (Diagnogreen®, Daiichi-Sankyo Pharma, Tokyo, Japan) was injected subcutaneously and intradermally into the core and 2 marginal regions of the tumor (3 injections in total), respectively. During surgery, the extent of the tumor was confirmed with a photodynamic eye, and the tumor was completely resected. A fluorescent portion macroscopically estimated as normal was additionally resected and no residual fluorescence or tumor were confirmed in the remaining tissue. Abnormal lymphatic vessels were histopathologically observed in the additionally resected tissue, indicating the invasion of LMs. The surgery had a good outcome with no evidence of recurrence. Conclusions: We performed near-infrared fluorescence-guided imaging surgery for the resection of LMs in the abdominal wall. This is a single case study; therefore, assessment of more cases is warranted for further validation. This procedure could provide significant benefit to patients requiring resection of LMs.
Pediatric Surgery International | 2018
Kazuki Yokota; Hiroo Uchida; Takahisa Tainaka; Yujiro Tanaka; Chiyoe Shirota; Akinari Hinoki; Takazumi Kato; Wataru Sumida; Kazuo Oshima; Kosuke Chiba; Tetsuya Ishimaru; Hiroshi Kawashima
PurposeThe Soave procedure (SO) is performed most commonly for Hirschsprung disease. SO reduces the risk of injury to the pelvic structures; however, a residual aganglionic muscle cuff could interfere with bowel movement and lead to obstructive enterocolitis. The Swenson procedure is considered ideal in terms of peristalsis. Currently, laparoscopic surgery provides better visualization and facilitates precise dissection, possibly leading to feasible performance of the laparoscopic modified Swenson procedure (SW). We present our operative technique and the efficacy of the SW compared with that of SO.MethodsWe retrospectively reviewed the records of 16 and 27 patients who underwent SW and SO, respectively, between 2012 and 2017.ResultsOperative time, blood loss, length of stay, and frequency of bowel movements showed no significant difference between the two groups. In the SW group, temporary dysuria occurred in one patient, postoperative enterocolitis in two, wound infection in one, and severe perianal excoriation in four, whereas in the SO group, obstructive symptoms occurred in three patients, small-bowel obstruction in one, and severe perianal excoriation in three. The complications and outcomes were comparable between both groups.ConclusionLaparoscopic SW was safe and feasible for the short-term follow-up outcomes.