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Gastroenterologia Japonica | 1983

Peritoneoscopy of the liver stained by intravenous injection of indocyanine green-experimental and clinical studies.

Toshio Ito; Tatsuya Itoshima; Minoru Ukida; Shozo Kiyotoshi; Kenji Kawaguchi; Hiromichi Ogawa; Masahiro Kitadai; Shuzo Hattori; Shigeki Mizutani; Keiji Kita; Ryoji Tanaka; Hideo Nagashima

SummaryLiver surface patterns were observed by peritoneoscopy after intravenous injection of indocyanine green (ICG). The normal rat liver was diffusely stained dark greenish-brown 5 minutes after the injection of ICG 25 mg/kg body weight into the tail vein. Green spots persisted longer in the centrolobular area, clearly revealing lobular markings. This regional difference in hepatocyte staining suggested differing abilities of hepatocytes to take up or excrete ICG. This dyeing technique was applied to liver disease patients. The liver was diffusely stained light greenish-brown 5 minutes after the injection of ICG 5 mg/kg body weight. In patients, especially those with obscure lobular markings before ICG injection, lobules were clearly demarcated by reddish terminal portal veins against a green background. This simplified detection of lobular distortions. Prenodular patches (Kalk’s Bunteflecke) on the liver surface were stained green more intensely than surrounding areas, which supports the hypothesis that patches are composed of active hepatocytes.


Gastroenterologia Japonica | 1987

Photodynamic therapy of rat liver cancer: Protection of the normal liver by indocyanine green

Keiji Kita; Tatsuya Itoshima; Toshio Ito; Hiromichi Ogawa; Minoru Ukida; Masahiro Kitadai; Shuzo Hattori; Shigeki Mizutani; Ryoji Tanaka; Masaharu Andoh; Norio Koide; Takayoshi Tanabe; Hideaki Kondoh; Michihiro Jitoku; Hideo Nagashima

SummaryThe application of photodynamic therapy (PDT) to hepatocellular carcinoma (HCC) has been difficult because hematoporphyrin derivatives (HpD) accumulate not only in cancer cells but also in normal hepatocytes and, hence, laser irradiation causes injuries in both tissues. Protection of the normal liver tissue from laser phototoxicity was demonstrated using indocyanine green (ICG) as a protective agent. In vitro, argon laser irradiation decolored the green tint of ICG much faster in solutions containing HpD than those without, suggesting that ICG captured singlet oxygen from HpD. Degeneration of Chang hepatocytes induced by HpD and laser irradiation was prevented by an addition of ICG into the medium. In vivo, laser irradiation of the rat liver surface caused hyperemia when HpD was injected two days before, while the hyperemia was much milder in rats additionally receiving ICG injection 10 minutes before the irradiation. ICG injected into rat HCC accumulated only in the normal liver tissue. Laser irradiation of rat HCC preinjected with both HpD and ICG destroyed only the cancer tissue, while the surrounding liver tissue was preserved.Both in vitro and in vivo results suggest that ICG has a scavenger effect against excited oxygen and it might be used as a protective agent in PDT of HCC.


Gastroenterologia Japonica | 1982

Peritoneoscopic study on rat liver cell necrosis induced by carbon tetrachloride and allyl formate

Toshio Ito; Tatsuya Itoshima; Shozo Kiyotoshi; Kenji Kawaguchi; Hiromichi Ogawa; Shuzo Hattori; Masahiro Kitadai; Toshihiro Maruyama; Hideo Nagashima

SummaryThe surface changes of acute centrolobular and perilobular necrosis were studied in rat liver using peritoneoscopy. Centrolobular necrosis was induced by carbon tetrachloride and perilobular necrosis by allyl formate. Vessels observed on the control rat liver surface were identified as terminal hepatic veins by irrigation of the hepatic vein with a barium solution. Polygonal whitish markings were observed on the liver surface 48 hours after carbon tetrachloride administration. Terminal hepatic veins were regularly distributed throughout the central portions of the whitish areas. Reddish spots about 0.1 mm in diameter were scattered about the terminal hepatic veins. The reddish spots and whitish areas corresponded to the histological findings of central liver cell necrosis and infiltration by Kupffer and white blood cells. Six hours after allyl formate administration, round reddish spots about 0.3 mm in diameter were regularly distributed on the liver surface among the terminal hepatic veins. These spots corresponded to the histological findings of liver cell necrosis around the portal area. In summary, acute centrolobular and perilobular liver cell necrosis were newly observed as reddish spots by peritoneoscopy.


Gastroenterologia Japonica | 1983

Scanning electron microscopy of a liver cavernous hemangioma

Kazuhide Yamamoto; Tatsuya Itoshima; Toshio Ito; Minoru Ukida; Hiromichi Ogawa; Masahiro Kitadai; Shuzo Hattori; Shigeki Mizutani; Hideo Nagashima

SummaryA 39-year-old female with a large cavernous hemangioma of the liver was successfully treated by ligation of the left hepatic artery. A wedge biopsy specimen of the hemangioma was obtained after the ligation and was examined by scanning electron microscopy. The hemangioma was demarcated from the surrounding normal liver parenchyma and had a labyrinth of caves 50–150 μm in diameter. The caves were separated by fibrous septa 20–40 μm in width. Endothelial cells of the caves were spindle-shaped and arranged in parallel. The surface property of the caves resembled that of the hepatic artery and differed from that of the portal vein or hepatic vein. These findings support that the cavernous hemangioma of the liver was supplied by the hepatic artery. The labyrinthine structure of the cavernous hemangioma may explain the long standing contrast enhancement of the hemangioma after hepatic arteriography.


Gastroenterologia Japonica | 1982

Differential diagnosis of liver parenchymal diseases by likelihood method using 12 laboratory data and age

Tatsuya Itoshima; Kenji Kawaguchi; Shigeru Morichika; Toshio Ito; Shozo Kiyotoshi; Hiromichi Ogawa; Shiro Yuasa; Shuzo Hattori; Masahiro Kitadai; Minoru Ukida; Hideo Nagashima

SummaryLiver parenchymal diseases were statistically diagnosed by likelihood method using 12 routine liver function tests and age. 444 cases of liver diseases were classified into 8 groups by histological diagnosis. A score diagnosis table was made from the data of these cases. For the likelihood diagnosis, data of each case were adapted to the score table and the probable diagnosis was calculated. Correct diagnosis rate of the first probable diagnosis was 50 % in all cases and that of the first and the second was 71%. Descending order of the correct diagnosis rate of the first diagnosis was fatty liver (76%), liver cirrhosis (67%), slight histological changes (61%), acute hepatitis (51%), alcoholic liver injury (48%), chronic aggressive hepatitis 2A (43%), chornic persistent hepatitis (40%) and chronic aggressive hepatitis 2B (26%). In conclusion, differential diagnosis of liver parenchymal diseases was made easily with the score table of 13 informations with a considerable success.


Gastroenterologia Japonica | 1983

Ranking of liver tests for differential diagnosis of liver parenchymal diseases

Tatsuya Itoshima; Kenji Kawaguchi; Shigeru Morichika; Toshio Ito; Shozo Kiyotoshi; Hiromichi Ogawa; Shiro Yuasa; Shuzo Hattori; Masahiro Kitadai; Shigeki Mizutani; Minoru Ukida; Hideo Nagashima

SummaryLiver function tests were ranked in the order useful to differentiate 8 liver parenchymal diseases in combination of tests by forward selection and backward elimination procedures in the likelihood method using a microcomputer. The orders were almost same in both procedures: indocyanine green plasma disappearance rate, glutamic pyruvic transaminase (GPT), zinc turbidity test, alkaline phosphatase, age, HBsAg, RA test, glutamic oxaloacetic transaminase (GOT)/GPT ratio, GOT, cholesterol, total protein, total bilirubin, albumin/globulin ratio and γ-globulin. The first 9 tests had almost all informations of all tests. The first likelihood diagnosis using the 9 tests was correct in 53% and the first or the second diagnosis was correct in 71 % of 444 cases of 8 liver parenchymal diseases. A score table of likelihood diagnosis using the 9 tests was presented for manual application to new cases.


Acta Medica Okayama | 1984

Lack of uptake of indocyanine green and trypan blue by hepatocellular carcinoma.

Tatsuya Itoshima; Toshio Ito; Minoru Ukida; Hiromichi Ogawa; Masahiro Kitadai; Shunzo Hattori; Shigeki Mizutani; Keiji Kita; Ryoji Tanaka; Norio Koide; Hideo Nagashima


Acta Medica Okayama | 1986

Injurious effects of ethanol on rat Kupffer cells.

Masahiro Kitadai; Tatsuya Itoshima; Hideo Nagashima


Acta Medica Okayama | 1985

Comparative diagnosis of alcoholic liver diseases by multivariate and histological analysis.

Masahiro Kitadai; Tatsuya Itoshima; Shuzo Hattori; Minoru Ukida; Toshio Ito; Hiromichi Ogawa; Shigeki Mizutani; Ryoji Tanaka; Keiji Kita; Hideo Nagashima


Acta Medica Okayama | 1984

Scanning electron microscopy of Ito's fat-storing cells in the rat liver.

Toshio Ito; Tatsuya Itoshima; Minoru Ukida; Kazuo Tobe; Shozo Kiyotoshi; Keiji Kawaguchi; Hiromichi Ogawa; Harumi Yamamoto; Shuzo Hattori; Masahiro Kitadai; Shigeki Mizutani; Takahiro Tsuchiya; Keiji Kita; Ryoji Tanaka; Hideo Nagasima

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