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Journal of Pediatric Surgery | 1994

Extensive dissection at the porta hepatis for biliary atresia

Akihiro Toyosaka; Eizo Okamoto; Tatsuo Okasora; Katsuyoshi Nose; Yoshifumi Tomimoto; Yasuji Seki

Dissection at the porta hepatis is the crucial step in surgery for biliary atresia. The authors describe their procedure for extensively dissecting the porta hepatis. The technique is based on an anatomic cast corrosion of the human liver, and the portal vein serves as the landmark for dissection. Lateral dissection at the hepatic hilus is critical to the procedure. On the right side, the anterior portal branches are dissected to the bifurcation of the S5 and S7 segmental portal branches, over the bifurcation of the anterior and posterior portal branches. On the left side, the liver parenchyma, which bridges the umbilical point, is sectioned, and the left portal branch is dissected to the umbilical point over the pars transversalis and taped. The fibrous mass that lies within the confines of the portal branches, including the dorsal aspect, is transected completely. This procedure was performed in 16 infants; the jaundice cleared in 93.7%.


Journal of Pediatric Surgery | 1993

Outcome of 21 patients with biliary atresia living more than 10 years

Akihiro Toyosaka; Eizo Okamoto; Tatsuo Okasora; Katsuyoshi Nose; Yoshifumi Tomimoto

The outcome of 21 survivors (8 males, 13 females; age range, 11 to 29 years) followed for > 10 years after surgery for biliary atresia are discussed. Of the 21 patients, 18 with type III disease had hepatic portoenterostomy (Kasai operation), and 3 with type I disease had hepaticoenterostomy. Twenty patients are alive leading almost normal lives; however, 13 (61.9%) patients did have a history of complications, including hemorrhage from esophageal varices in 10, from a gastric ulcer or erosion in 3, and from a duodenal ulcer in 2; biliary reobstruction in 3; and multiple pulmonary arteriovenous fistulae in 2. Of those with complications, 7 required surgery. One died suddenly at the age of 19 years of a bleeding gastric ulcer. Liver function is normal in 9 (45.0%) of the 20 alive patients, 2 (10.0%) have slight hepatic dysfunction, and 9 (45.0%) have mild-to-moderate hepatic dysfunction. Liver function is almost normal in 3 patients who had a history of variceal hemorrhage.


Journal of Pediatric Surgery | 1984

Esophageal perforation in a neonate associated with gastroesophageal reflux.

Ken Kimura; Masako Kubo; Tatsuo Okasora; Takao Eto; Chikara Tsugawa; Yoichi Matsumoto

This is the first report of a neonate with esophageal perforation in whom an association of gastroesophageal reflux (GER) was detected by esophagraphy and esophageal pH monitoring. The patient was successfully treated for both esophageal perforation of GER by thoracic drainage and fundoplication. In this patient, GER seemed a likely cause of esophageal perforation.


Clinical Autonomic Research | 1993

Clinical, laboratory and prognostic features of congenital large intestinal motor dysfunction (pseu do-Hirschsprung's disease)

Akihiro Toyosaka; Eizo Okamoto; Tatsuo Okasora; Katsuyoshi Nose; Yoshifumi Tomimoto

One hundred and forty-eight cases of congenital large intestinal motor dysfunction (pseudo-Hirschsprungs disease) were reported by members of the Japanese Society of Pediatric Surgeons during the past 20 years. The disorder was defined as a congenital, non-mechanical obstruction of the intestine with the presence of intramural ganglia in the terminal rectum. Intramural ganglia were abnormal in 77 cases, normal in 42, and could not be determined in 29. Of those with abnormal intramural ganglia, 54 had immature ganglia or hypoganglionosis (oligoganglionosis), 15 had neuronal intestinal dysplasia, and eight had a segmental anomaly. Of those with a normal myenteric plexus, 22 had chronic and twelve had suspected idiopathic intestinal pseudo-obstruction syndrome; eight had megacystis-microcolon-intestinal hypoperistalsis syndrome. While cases with both hypoganglionosis and normal intramural ganglia had normal acetylcholine esterase activity, a significantly greater number of patients with hypoganglionosis lacked normal rectoanal reflexes. Patients with hypoganglionosis, chronic idiopathic intestinal pseudo-obstruction syndrome, and megalocystis-microcolon-intestinal hypoperistalsis syndrome had poor prognoses with an overall mortality of 36.9%. These findings indicate that congenital large intestinal motor dysfunction remains a serious disease of childhood.


Surgery Today | 1995

Sporadic visceral neuropathy

Hirofumi Niwamoto; Eizo Okamoto; Akihiro Toyosaka; Yasuhiro Matsushima; Tatsuo Okasora

We encountered three cases of chronic functional colonic obstruction caused by intramural ganglion cell death. Morphologic and pharmacological studies were performed using resected specimens. The patients included a 59-year-old man, a 72-year-old woman, and a 28-year-old man. Barium enema studies revealed segmental stenosis in their left colon. A mecholyl test was positive in all three cases and was useful in diagnosing this disorder. Histopathologic and cytometric examinations disclosed both degeneration and the disappearance of intramural ganglion cells. The number of muscarinic acetylcholine receptors was observed to increase in the muscle layers of the stenotic portion. In addition, the muscle of the affected region showed hypersensitivity to the muscarinic agonist (oxotremorine). These results seem to suggest that this disease is caused by a noncongenital injury to the intramural ganglion cells while the resulting stenosis is considered to reflect the degeneration of the ganglion cells. The etiology of ganglion cell death still remains to be clarified; however, we propose that patients with this disorder may represent a subset of patients with sporadic visceral neuropathy.


Journal of Pediatric Surgery | 1993

Successful Kasai operation for biliary atresia in a 9 month old

Akihiro Toyosaka; Eizo Okamoto; Eisuke Kawamura; Tatsuo Okasora; Katsuyoshi Nose; Yoshifumi Tomimoto; Yasuji Seki

A rare case of a successful Kasai operation for biliary atresia in a 9 month old is described. For infants over 6 months of age, there had been no reports of long-term survival after this procedure.


Pediatric Surgery International | 1987

The use of ultrasonography in the diagnosis of biliary atresia

Tatsuo Okasora; Akihiro Toyosaka; Toshihiro Muraji; Katsuyoshi Nose; Eizo Okamoto

Preoperative upper abdominal ultrasonograms of babies with biliary atresia were reviewed in order to determine the efficacy of this technique in the differential diagnosis of biliary atresia and neonatal hepatitis. In 4 patients with neonatal hepatitis and 8 normal controls, ultrasonograms showed echoes of the gallbladder. In 14 patients with biliary atresia, echoes of the gallbladder were not apparent. It is concluded that preoperative ultrasonograms provide an efficient diagnostic method for differentiating biliary atresia from neonatal hepatitis.


Pediatric Surgery International | 1994

Endoscopic treatment of severe esophageal strictures in children by combined proximal and distal approaches

Akihiro Toyosaka; Eizo Okamoto; Akiyoshi Shu; Yousuke Yoden; Tatsuo Okasora; Katsuyoshi Nose; Yasuji Seki

One patient with complete reobstruction following repair of congenital esophageal atresia and another with a severe esophageal stricture due to reflux esophagitis were treated successfully with endoscopic electroincision from both the proximal and distal ends combined with dilation by Tuckers endless bougie. There have been no previous reports of this technique being used for severe esophageal stenosis in children. This method can be applied safely to children with severe esophageal strictures in which no guidewire or other bougie can be passed, a clinical situation previously requiring open surgery.


Nihon Heikatsukin Gakkai zasshi | 1990

[Study on function of aganglionic colon musculature of Hirschsprung's disease murine model].

Tatsuo Okasora; Eizo Okamoto; Akihiro Toyosaka; Katsuyoshi Nose; Yoshiyuki Nakai; Yoshifumi Tomimoto


Jpn J Gastroenterol Surg, Nihon Shokaki Geka Gakkai zasshi | 1991

Pathomorphological and angiographic studies on intrahepatic metastasis of hepatocellular carcinoma. With special reference to efferent vessel of the tumor.

Akihiro Toyosaka; Eizo Okamoto; Tatsuo Okasora; Naoki Yamanaka; Masao Mitsunobu; Takeshi Oriyama; Jiro Fujimoto

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Eizo Okamoto

Hyogo College of Medicine

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Katsuyoshi Nose

Hyogo College of Medicine

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Yasuji Seki

Hyogo College of Medicine

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Akiyoshi Shu

Hyogo College of Medicine

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Masao Mitsunobu

Hyogo College of Medicine

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Yoshiyuki Nakai

Hyogo College of Medicine

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Akio Kyo

Hyogo College of Medicine

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Eisuke Kawamura

Hyogo College of Medicine

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