Jun Yanagihara
Kyoto Prefectural University of Medicine
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Annals of Surgery | 1992
Naomi Iwai; Jun Yanagihara; Kazuaki Tokiwa; Takashi Shimotake; Kaori Nakamura
Of 37 patients with congenital choledochal dilatation, aged 8 days to 12 years, who had undergone excision with Roux-en-Y hepaticojejunostomy, 26 patients could be analyzed for morphologic abnormalities and pathophysiology of the biliary tract. Of the 26 patients with congenital choledochal dilatation, 25 (96.2%) had an abnormal choledochopancreaticoductal junction. Of the 12 patients with cystic-type choledochal dilatation, 10 had the C-P type of abnormal choledochopancreaticoductal junction, and of the 13 patients with fusiform-type choledochal dilatation, nine had the P-C type. The amylase levels in the choledochal cyst and the gallbladder were elevated regardless of the form of choledochal dilatation. An adenocarcinoma in a cystic choledochal dilatation was found in one child. Therefore, longstanding inflammation of the biliary tract caused by the reflux of pancreatic juice might be one of the factors in carcinogenesis in the biliary tract. This free reflux of pancreatic juice was demonstrated not only by amylase levels in the biliary tract but also by intraoperative biliary manometry. This reflux might be explained by the lack of sphincter function at the junction of the common bile and pancreatic ducts.
Journal of Pediatric Surgery | 2000
Sachiyo Suita; Takao Okamatsu; Tetsuro Yamamoto; Noritoshi Handa; Yuji Nirasawa; Yasuhiro Watanabe; Jun Yanagihara; Eiji Nishijima; Seiichi Hirobe; Masaki Nio; Akira Gomi; Minoru Horisawa
BACKGROUND/PURPOSE The incidence of gastroschisis has increased over the past 3 decades in a number of countries. To elucidate the Japanese status of anterior abdominal wall defects, the Japanese Society of Pediatric Surgeons conducted a national survey in Japan. METHODS Information was obtained by sending out a questionnaire to 192 University Hospitals, Childrens hospitals, and general hospitals that each had more than 200 beds. The characteristics of the patients including the birth date, birth weight, gestations, rate of associated anomalies, rate of antenatal diagnosis and prognosis, maternal age, gravidity, history of smoking, and drug use were analyzed. RESULTS The authors obtained answers from 149 institutions, including 1,785 cases of omphalocele and 970 cases of gastroschisis, which were treated between 1975 to 1997. There was a significant increase in the incidence of gastroschisis, from 0.131 in 1975 to 1980, 0.269 in 1981 to 1985, 0.337 in 1986 to 1990, 0.461 in 1991 to 1995 to 0.467 per 10,000 births in 1996 to 1997. The incidence of omphalocele was 0.322 in 1975 to 1980, 0.567 in 1981 to 1985, 0.657 in 1986 to 1990, 0.741 in 1991 to 1995 to 0.626 per 10,000 births in 1996 to 1997, respectively. In the omphalocele group, 43.1% of the mothers were between 25 to 29 years of age, whereas in the gastroschisis group 42.6% of the mothers were 20 to 24 years of age. In the gastroschisis group, the number of primipara mothers was larger than that of multipara mothers. In the omphalocele group, approximately 10% of the mothers smoked during each period, whereas in the gastroschisis group, the percentage of smoking mothers increased chronologically from 12.9% in 1981 to 1985, 18.7% in 1986 to 1990, 23.5% in 1991 to 1995 and 29.3% in 1996 to 1997. A history of drug use by the mother was approximately 10% for both the omphalocele and gastroschisis groups. In the omphalocele group, 55.9% had associated anomalies against 21.8% in the gastroschisis group. Approximately 10% in the omphalocele group and less than 3% in the gastroschisis group showed chromosomal abnormalities. From 1986, a significant number of cases detected antenatally has been observed. CONCLUSIONS There have been substantial changes in the incidence of anterior abdominal wall defects, particularly regarding gastroschisis in Japan. The reasons for such changes are most likely multifactorial, further epidemiological monitoring is thus called for.
Journal of Pediatric Surgery | 1990
Naomi Iwai; Eiichi Deguchi; Jun Yanagihara; Masaki Iwai; Hiroyuki Matsuo; Shinjiro Todo; Shinsaku Imashuku
An adenocarcinoma was found in a choledochal cyst in a 12-year-old girl. This is the youngest patient so far reported with an adenocarcinoma in a choledochal cyst. The cyst consisted of dilatations of the intrahepatic bile ducts and the extrahepatic bile duct. Most of the cyst wall was resected. However, resection of the distal part of the cyst wall in the infrapancreatic region was impossible because of invasion of the portal vein and the inferior vena cava. This patient is now being treated with chemotherapy. We believe that early diagnosis is mandatory, and that total excision of a choledochal cyst is advisably to prevent the development of carcinoma.
Journal of Pediatric Surgery | 1985
Toshiaki Tsuto; Hitoshi Okamura; Kenji Fukui; Hiroko L. Obatatsuto; Terubayashi H; Jun Yanagihara; Naomi Iwai; Susumu Majima; Noboru Yanaihara; Yasuhiko Ibata
The distributions of gut hormones in the colon of Hirschsprungs disease were investigated by the peroxidase-antiperoxidase (PAP) immunohistochemical method. Three colonic segments (ganglionic, oligoganglionic, and aganglionic) were stained by the unlabeled antibody enzyme method. The immunoreactivity of vasoactive intestinal polypeptide (VIP) was found to be reduced in the oligoganglionic and aganglionic segments. Antisera to substance P and met-enkephalin demonstrated immunoreactive cells and fibers in the ganglionic segment, whereas these cells and fibers were almost completely absent in the oligoganglionic and aganglionic segments. A similar distribution was seen for the mucosal endocrine cells with somatostatin immunoreactivity. Antisera to neurotensin, motilin, bombesin, and cholecystokinin revealed no immunoreactivity in the normal colon or the three segments. The differences in these peptides between normal and impaired colonal segments may be one of the causes of colon constriction in Hirschsprungs disease.
Journal of Pediatric Surgery | 1998
Yoshihiro Kubota; Takashi Shimotake; Jun Yanagihara; Naomi Iwai
PURPOSE To investigate the pathogenesis of anorectal malformations (ARM), the authors studied cell proliferation and programmed cell death (apoptosis) patterns in murine embryos that develop ARM as a result of administering an overdose of etretinate, a long-acting vitamin A analogue (retinoid). METHODS Pregnant mice were fed 60 mg/kg of etretinate on the ninth gestational day (E9). Embryos were obtained between E9.5 and E13, and prepared for histological study. Cell proliferation was examined using proliferative cell-specific nuclear antigen (PCNA) expression. Apoptosis was identified by detecting in situ DNA fragmentation using the TdT-mediated dUTP-digoxigenin nick end-labeling (TUNEL) method. RESULTS Over 95% of etretinate-treated embryos had ARM including rectoprostatic urethral or rectocloacal fistula. In the histological study, ARM embryos showed defective cell proliferation in the cloacal membrane and excessive apoptosis in the dorsocaudal region on E11, which resulted in a lack of apoptosis in the anal orifice and a short tail on E12, respectively. Cells forming the urorectal septum showed the same pattern of cell proliferation and apoptosis both in ARM embryos and the controls. These results suggest that impairments of embryonal cellular dynamics in the cloacal membrane and dorsocaudal region induce some types of ARM.
Journal of Pediatric Surgery | 1986
Naomi Iwai; Kazuaki Tokiwa; Toshiaki Tsuto; Jun Yanagihara; Toshio Takahashi
Intraoperative manometry of the biliary tract and measurement of amylase levels in choledochal cysts were performed in seven patients, aged 14 months to 5 years, with choledochal cysts, in an investigation of the pathophysiology of the biliary tract. An abnormal choledochopancreatico ductal junction was observed in these seven patients by preoperative endoscopic retrograde cholangiopancreaticography (ERCP) or intraoperative cholangiograms. All six patients examined showed a high amylase level in the choledochal cyst (5,450 to 46,500 Somogyi Units). The intraoperative manometry of the biliary tract showed that a remarkable high pressure zone as was found in the area of sphincter of Oddi was not found in the area of abnormal choledochopancreatico ductal junction. The pressure recordings also demonstrated that the sphincter of Oddi pressure in the patient with choledochal cyst was increased by gastrin stimulation. On the contrary, no pressure reaction to gastrin or secretin was found in the area of abnormal choledochopancreatic ductal junction. From these results it seems that free reflux of pancreatic juice into the biliary system occurs, and the reflux stream depends upon the pressure gradient between pancreatic ductal pressure and common bile duct pressure because of the lack of a sphincter function at the choledochopancreatico ductal junction.
Annals of Surgery | 1988
Naomi Iwai; Jun Yanagihara; Kazuaki Tokiwa; Eiichi Deguchi; Toshio Takahashi
Of 119 patients with surgical correction of anorectal malformations, 47 who were 10-30 years of age were interviewed personally and had manometric studies to evaluate postoperative continence. This clinical study included not only long-term anorectal function but also sexual function. Patients with low type anomalies or with intermediate type anomalies were more likely to be continent, whereas patients with high type lesions had some problems with continence. However, only two of the 16 patients (12%) with high type anomalies were classified as having poor results. This rate is perhaps lower than might be expected. Thus, incontinent patients may become continent even if they were classified as having fecal incontinence before 6 years of age. Most patients who were 15-30 years of age had normal sexual function except for two females with irregular menstruation. These results indicate that achievement of fecal continence and sexual function in patients with high type anomalies treated by abdominoperineal rectoplasty depends on careful dissection as close as possible to the rectal wall and bringing the terminal bowel down exactly within the sling of the puborectal muscle.
Journal of Pediatric Surgery | 1997
Naomi Iwai; George Iwata; Osamu Kimura; Jun Yanagihara
PURPOSE The authors devised computerized equipment for use in the biofeedback therapy in the management of fecal continence after surgery for anorectal malformations. METHODS The therapy was used for two to eight sessions in 14 children (11 who had high-type anomalies and three who had intermediate-type anomalies). The ages ranged 5 to 14 years. A control group of 17 children, aged 5 to 11 years, who had encopresis, was also treated with the same biofeedback therapy. RESULTS Clinical improvement was noted in 5 of the 14 (36%) children who had fecal incontinence, and in 15 of the 17 children (88%) who had encopresis. Both in patients who had fecal incontinence and in those who had encopresis, anal resting pressures were not affected by biofeedback therapy. Furthermore, the anal resting pressure in children who had fecal incontinence was significantly lower than that in children who had encopresis. However, anorectal manometry showed that the biofeedback therapy improved voluntary sphincter function and rectal sensation in both groups. CONCLUSION Biofeedback therapy appears to be effective in most children who have encopresis whose sphincter function is intact, and in some children who have fecal incontinence after surgery for anorectal malformations.
Journal of Pediatric Surgery | 1988
Naomi Iwai; Jun Yanagihara; Kazuaki Tokiwa; Eiichi Deguchi; Toshio Takahashi
Electromyography (EMG) and measurement of voluntary contraction pressure of the external sphincter muscle were performed in 28 patients, aged 5 to 14 years, to assess the function of the external sphincter after surgical correction of anorectal malformations. Ten normal children, aged 5 to 15 years, served as controls. External sphincter function in patients with high-type anomalies was disturbed in the areas of tonic activity, inflation reflex, and activity during further rectal filling. In patients with low-type or intermediate-type anomalies, function was preserved and was equal to that in normal controls. Phasic activity was observed in patients with all types of anomalies and in normal subjects. Among those with high-type anomalies, the three patients with Kellys score of less than 2 had voluntary contractions of 20 cmH2O or less. However, the mean voluntary contraction pressures were not significantly different among the three types of anomalies. Therefore, patients with high-type anomalies may acquire compensatory voluntary continence through bowel training.
Journal of Pediatric Surgery | 1997
Ryoichi Fukata; Naomi Iwai; Jun Yanagihara; George Iwata; Yoshihiro Kubota
Anal endosonography, electromyography (EMG) of the external anal sphincter (EAS), and manometry of the internal anal sphincter (IAS) were performed in 15 patients with anorectal anomalies (10 with high and five with intermediate anomalies), ranging in age from 8 to 18 years. The anal endosonographic findings were compared with those for the EMG of the EAS and manometry of the IAS. An image including the hyperechoic band that corresponds to the EAS was obtained in all 15 patients. However, the distribution of EAS image was inadequate in high anomalies. In four patients who showed in Kelly score of 5 or 6, good visualization of the EAS was obtained in both anal endosonography and EMG. An Image including the hypoechoic band that corresponds to the IAS was obtained in five patients with high anomalies and in one with intermediate anomalies. Therefore, even in patients with anomalies, at these levels the IAS could be ultrasonically detected. However, only one of these six patients exhibited an anorectal reflex. These results indicate that, for the EAS, the findings of anal endosonography correspond well with those of EMG, but that for the IAS, they do not correspond with those of manometry. At the time of surgery for anorectal anomalies care should taken to preserve the IAS, which can be detected by anal endosonography even in patients with high or intermediate anomalies.