Colloid liver scintigraphy has been performed widely for diagnosis of diffuse parenchymal liver disease. Pattern of these disease such as chronic hepatitis or liver cirrhosis is evaluated by size and distortion of the liver, distribution of tracer in the liver, size and activities of tracer in the spleen, visualization of the bone marrow and so on. It is not difficult to read a scintigram which shows typical pattern of normal, chronic hepatitis and liver cirrhosis, but in some cases it is difficult to read normal or chronic hepatitis and chronic hepatitis or liver cirrhosis in visual diagnosis. So we tried to use fuzzy reasoning to make differential diagnosis accurately.
