Youkatsu Ohhama
Juntendo University
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Publication
Featured researches published by Youkatsu Ohhama.
Journal of Pediatric Gastroenterology and Nutrition | 2009
Masato Shinkai; Youkatsu Ohhama; Hiroshi Take; Norihiko Kitagawa; Hironori Kudo; Kyoko Mochizuki; Tomoko Hatata
Objective: Sequential strategies combining the Kasai operation as a first-line treatment and liver transplantation as a second-line option, if necessary, have been accepted for patients with biliary atresia (BA). To understand the role of the Kasai operation in the treatment of BA, it is necessary to analyze the long-term outcome of the operation alone and to evaluate the present status of survivors retaining their native livers. Materials and Methods: A retrospective chart review was carried out for a group of 80 patients who had undergone the Kasai operation between 1970 and 1986 at the Kanagawa Childrens Medical Center. Results: The 5-, 10-, and 20-year survival rates of patients with their native livers were 63%, 54%, and 44%, respectively. The survival rates varied significantly depending on the type of BA, age at initial Kasai operation, era of surgery, and surgical method. By age 20, nearly half of the adult survivors had already developed liver cirrhosis and its sequelae. Episodes of cholangitis and gastrointestinal bleeding occurred after 20 years of age in 37% and 17% of the adult patients, respectively, and 20% of the adult patients died of liver failure or underwent living-related partial liver transplantation in their 20s. Five female patients gave birth to a total of 9 children, and 1 male patient fathered a child. Conclusions: Although increasing numbers of patients with BA survive 20 years or more after the Kasai operation, meticulous lifelong postoperative care should be continued for the survivors because of the possibility of hepatic deterioration.
Pediatric Surgery International | 2003
Tadashi Iwanaka; Mari Arai; Hirotoshi Yamamoto; Masahiro Fukuzawa; Akio Kubota; Katsunori Kouchi; Masaki Nio; Akira Satomi; Fumiaki Sasaki; Akihiro Yoneda; Youkatsu Ohhama; Takehara H; Yasuhide Morikawa; Takeshi Miyano
Port-site recurrence (PSR) following laparoscopic procedures has been an unpredictable complication in adult cancer patients; however, no data exist about this phenomenon in the pediatric field. The aim of this study was to determine whether PSR, following endosurgical procedure for malignancies, is a typical complication or a rare event in the pediatric population. Eighty-one questionnaires were mailed to members of The Japanese Society of Pediatric Endosurgeons. They were asked to provide a list of their institutions that had experience with PSR after endosurgical procedures for pediatric malignancies. Among 29 institutions, a total of 129 endosurgical procedures for pediatric malignancies were reported; these included 85 laparoscopic and 44 thoracoscopic procedures, performed on 104 neuroblastomas, 8 hepatoblastomas, 7 nephroblastomas, and 10 other tumors. Of the 104 neuroblastomas, 83 were found by mass screening using high levels of urinary vanillylmandelic acid and homovanillic acid. Sixty-five of the 83 patients had their tumor excised, and 18 had their tumor biopsied by endosurgical procedures. Additionally, 47 of these patients did not require any postoperative chemotherapy. No incidence of PSR was reported in any of the patients that underwent endosurgical procedures. The PSR following endosurgical procedure is a rare phenomenon in the pediatric population. Both, laparoscopic and thoracoscopic procedures, are safe and recommended for treating pediatric malignancies, especially mass-screened neuroblastomas.
Journal of Pediatric Surgery | 2003
Masato Shinkai; Youkatsu Ohhama; Hiroshi Take; Yoshimitsu Fukuzato; Shogo Fujita; Toshiji Nishi
PURPOSE The authors evaluated the validity of the Pediatric End-Stage Liver Disease (PELD) Risk Scoring System as a severity index for patients with biliary atresia. METHODS Individual hospital records of 104 patients with biliary atresia were reviewed at our institution and divided into 3 groups: nontransplant survivors (n = 61), nontransplant deaths (n = 17), and transplant patients (n = 26). PELD risk scores were calculated according to Wiesner et al, multiplied by 10, and rounded to the nearest integer, as is done in determining model of end-stage liver disease (MELD) scores. RESULTS The PELD scores showed a significant difference between nontransplant survivors (range, -21 to 15) and dying nontransplant patients during their last few months of life (range, 2 to 40). No survivors except those below the age of one year recorded scores above 10. Transplant patients had higher scores (range, -5 to 37) before transplantation than nontransplant survivors. However, the scores were not elevated in elderly patients with intractable cholangitis, fulminant variceal rupture, and hepatopulmonary syndrome. CONCLUSIONS PELD profiling is a useful scoring system for selecting patients with the most severe liver dysfunction caused by biliary atresia. However, we advise caution in using this system for patients under the age of 1 year and for older patients with long-term complications.
Journal of Computer Assisted Tomography | 2002
Tetsu Niwa; Noriko Aida; Katsuhiko Tachibana; Masato Shinkai; Youkatsu Ohhama; Kazutoshi Fujita; Aya Abe; Jin Lee; Yukihiko Ozawa; Tomio Inoue
Congenital absence of the portal vein (CAPV) is a rare anomaly in which the intestinal and splenic venous drainage bypasses the liver and drains into the systemic veins through various venous shunts. In patients with CAPV, the portosystemic shunting causes disruption of the enterohepatic circulation and leads to various clinical manifestations. CAPV can be diagnosed without invasive techniques. This article illustrates the clinical and radiologic findings (including ultrasound, CT, and MRI) of CAPV.
European Journal of Pediatrics | 2004
Masanori Adachi; Masato Shinkai; Youkatsu Ohhama; Katsuhiko Tachibana; Tadatoshi Kuratsuji; Hiroh Saji; Etsuko Maruya
Patients with glycogen storage disease type 1b (GSD1b) not only show hepatomegaly, hypoglycaemia and lactic acidosis, but also neutropenia and neutrophil dysfunction. Here, we report improvement of neutropenia and neutrophil function in a 22-year-old male GSD1b patient who had undergone living-related partial liver transplantation (LT) at 18 years of age. After LT, the patient’s infectious episodes decreased, gastrointestinal symptoms ameliorated, neutrophil counts increased, and neutrophil function tests normalised. Conclusion:although it is not known whether this improvement was causally related to liver transplantation, this may be the first recorded case of restoration of neutrophil dysfunction in a glycogen storage disease type 1b patient.
Journal of Pediatric Surgery | 2010
Shohei Honda; Masato Shinkai; Yoshiko Usui; Yoshihiro Hirata; Norihiko Kitagawa; Hiroshi Take; Youkatsu Ohhama
Ingestion of a button battery has been considered a serious problem, causing necrosis and perforation, when impacted in the esophagus. However, such batteries in the stomach rarely cause any harm to the gastric wall, which is regarded as evidence supporting the use of conservative treatment. We present the rare case of a 3-month-old infant with severe gastric wall injury caused by a button battery lodged in the stomach. The present case suggests that button batteries located in the stomach should be removed as soon as possible, especially in infants.
Journal of Pediatric Surgery | 2011
Kiyoshi Gomi; Norihiko Kitagawa; Yoshiko Usui; Mio Tanaka; Mariko Yoshida; Yoshihiro Hirata; Taiichiro Kosaka; Shohei Honda; Hiroshi Take; Masato Shinkai; Ayako Shishikura; Noriko Aida; Youkatsu Ohhama; Yukichi Tanaka
We report a case of papillary carcinoma (PC) with extensive squamous metaplasia arising from a thyroglossal duct cyst (TDC) that required differential diagnosis from squamous cell carcinoma (SCC). An 11-year-old Japanese girl presented with a 9-month history of an anterior-midline neck mass that was clinically diagnosed as TDC. Open neck biopsy revealed nested proliferation of atypical squamous cells within the cystic structures, and SCC arising from TDC was initially suspected. Further examination, however, including immunohistochemistry, revealed the tumor to be of thyroid cell origin. The patient underwent wide local resection of the thyroglossal duct carcinoma by Sistrunk procedure and cervical lymph node dissection. Microscopically, the diagnosis was of PC with extensive squamous metaplasia and metastasis to the medial submandibular lymph node. Distinction of squamous metaplasia in PC from SCC is sometimes difficult, but has a significant effect on postoperative management.
Pediatric Surgery International | 2004
Norihiko Kitagawa; Youkatsu Ohhama; Yoshimitsu Fukuzato; Hiroshi Take; Masato Shinkai; Toshiji Nishi; Michiko Yamanaka; Noriko Aida; Keisuke Kato; Akikatsu Toyoshima
A case of pericardial hemangioma is described which was resected in the neonatal period due to its effect on the cardiopulmonary system. Preoperative differential diagnosis of a teratoma was difficult. Surgical extirpation resulted in massive bleeding and postoperative bronchomalacia. These complications suggest that we should choose a conservative therapy as often as possible.
Pediatric Surgery International | 2009
Masato Shinkai; Kyoko Mochizuki; Yoshihiro Hirata; Shohei Honda; Norihiko Kitagawa; Hiroshi Take; Youkatsu Ohhama; Mio Tanaka; Yukichi Tanaka
We present a rare case of a female neonate with an imperforate anus associated with a perineal mass which may correspond to an extrophied rectal duplication. Associated anomalies were thoracic hemivertebrae and a multicystic dysplastic kidney. Excision of the perineal lesion followed by anal transplantation and perineal reconstruction corrected the anomaly.
Pediatric Surgery International | 2006
Noboru Oyachi; Youkatsu Ohhama; Hiroshi Take; Yoshimitsu Fukuzato; Toru Murakami; Norihiko Kitagawa; Hironori Kudo
The authors describe a rare case of choledochal cyst and aplasia of the dorsal pancreas complicated with chronic pancreatitis. A 9-year-old boy presented with obstructive jaundice. After biliary drainage using pericutaneous transhepatic gallbladder drainage (PTGBD) technique, the patient underwent choledochal cyst excision with Roux-en-Y hepaticojejunostomy. The association of choledochal cyst and aplasia of the dorsal pancreas with chronic pancreatitis has never been reported previously.