The Role Of Intracranial Tumor Imagings With Multiple Brain Function Imaging Agents

Purpose: Different combinations of brain imagings with multiple brain imaging agents ( ^99mTc-ECD, ^99mTc-MIBI and ^99mTc-DTPA ), which were available domestically, were performed in our study: 1. to clarify the characteristics of various brain tumors with each imaging agent; 2. to find out the role of these characteristics in the diagnosis of intracranial masses; 3. to study the complementarity of different imaging agents; 4. to establish possible combination procedures and making preliminary evaluation.Methods: 50 patients (male 21, female 29; mean age 42.7±12.6 yr.) with highly suspicious brain tumor by CT and / or MRI examination were enrolled in this study. All cases were studied with brain blood flow and brain imagings using ^99mTc-ECD, ^99mTc-MIBI and /or ^99mTc-DTPA before operation. The acquisition was started 20 to 30 min after intravenous injection of 15 MBq.Kg^{-1 99m}Tc-ECD or ^99mTc-MIBI, but 5 min after injection of ^99mTc-DTPA. All images were assessed both visually and semiquantitatively. Semiquantitative analysis was carried out using ROI method and the uptake ratio, T/N, was calculated. The final diagnoses of all 50 patients were proved surgically and pathologically.Results: 1. Blood flow study Abnormal radioactivity was observed during the arterial phase of blood flow study in 30/48 (62.5%) patients, including 24/33 extracerebral and 6/16 intracerebral tumors. Nine cases of extracerebral lesions had negative findings, including 3 small and one blanket like meningiomas, 1 cystic neurinoma, 1 cavernous hemangioma and 3 nontumor lesions. All positive findings of intracerebral tumors were malignant lesions.2. ^99mTc-ECD study There were abnormal findings in 39 of 40 patients performed with ECD study. An oval or round concave cortical...