[The assessment of tumor blood flow factors using dynamic CT--a comparison with positron emission tomography]

The dynamic computed tomography (CT) was performed by using rapid-sequence scanning following an intravenous bolus injection of contrast material. Time-density curve was applied for Gamma variate curve fitting and CT attenuation values were applied for two compartment model. The value of 1/CM, k1 and k2 were defined as the blood flow factors in this study. The inhalation of C15O2 using positron emission tomography (PET) can be useful for determining regional tumor blood flow (rBF). CT and PET were performed in twelve patients. The diagnosis was malignant lymphoma in four, and others; two liver metastasis, one focal nodular hyperplasia of the liver, one dermatofibrosarcoma, one hepatocellular carcinoma, one malignant melanoma, one malignant meningioma, one bone metastasis. The correlations among rBF, 1/CM, and k1 were good, and better correlations were obtained among tumor blood flow factors and rBF in the case of the tumors which existed far from air way and/or had low blood flow. The distance from air way effected both the value of rBF and tumor blood flow factors. Both the distance from air way and pathology caused conflicting results between rBF and tumor blood flow factors. Dynamic CT was particularly useful for evaluated the blood flow of tumors that had contact with air way.