Light dosimetry of liver tissues and hepatic tumors in rats and human. --Experimental study and its application--

Research Project

Project/Area Number	62570563
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	General surgery
Research Institution	Hamamatsu University School of Medicine
Principal Investigator	NAKAMURA Satoshi 2nd Dept. of Surgery, Hamamatsu University School of Medicine, 医学部, 講師 (00090027)
Co-Investigator(Kenkyū-buntansha)	YAMASHITA Yutaka Hamamatsu Photonics Co., Ltd., 研究部 SAKAGUCHI Shukichi Vice-president of Hamamatsu University School of Medicine, 医学部, 副学長 (30107809) 西脇由朗浜松医科大学, 医学部, 医員
Project Period (FY)	1987 – 1988
Project Status	Completed (Fiscal Year 1988)
Budget Amount *help	¥1,800,000 (Direct Cost: ¥1,800,000) Fiscal Year 1988: ¥600,000 (Direct Cost: ¥600,000) Fiscal Year 1987: ¥1,200,000 (Direct Cost: ¥1,200,000)
Keywords	Light dosimetry of the tissues / Penetration depth of light / hepatic tumors / Dosimetry / レーザ / 光透過性 / 光のDosimetry
Research Abstract	The attenuation of light in the liver and hepatic tumors of rats and human was measured in the 410, 630, and 670 nm wavelengths. Optical fiders coupled to a photon counting system were positioned within the tissues to determine light flux, and were attached to a caliper gauge to measure the distance of the fiber separation. Five resected specimens of metastatic carcinoma from the colon with normal liver, and hepatocellular carcinoma with cirrhosis of the liver were used immediately after surgical resection. Metastatic tumors showed the deepest penetration at all wavelenhths. A significant difference appeared between the cancerous and noncancerous tissues (p 0.01). Additionally, the cirrhotic liver tissues showed significant deep penetration by all wavelengtsexamined in comparison with normal liver tissues (p 0.01). The penetration depth of rat liver tissues with a veriety of hepatic diseases showed grossly the same tendency with those of the human resected hepatic tisues and tumors. Light dosimetry of hepatic tissues and tumors showed a potentiality of differentiation between cancerous and noncancerous tissues in its clinical application and photodynamic therapy of the hepatic tumors. In the photodynamic therapy of malignancies, 670 nm light shou ld be recommended.