Cerebral blood flow imaging in patients with brain tumor and arterio-venous malformation using Tc-99m hexamethylpropylene-amine oxime

Single photon emission computed tomography of the brain using a ring type gamma-camera (SET-020, Shimadzu Co.), following intravenous injection of Tc-99m hexamethylpropylene-amine oxime (HM-PAO) was studied in 20 patients with brain tumors (meningioma; 4, astrocytoma; 6, pituitary tumor; 1, germinoma; 1, metastases; 5, arterio-venous malformation (AVM); 3). Ratios of tumor activities to those of contralateral sides (T/N ratios) are calculated, and they were compared to those obtained by Xe-133 and IMP. In 17 patients, HM-PAO and IMP activities are low in the lesion of tumor and edema regardless of tumor type. High activities of HM-PAO are observed in 2 patients with meningioma and in 1 patient with high grade astrocytoma, and high activity of IMP was observed in 1 patient with meningioma and in 1 patient with high grade astrocytoma. Correlation coefficients of T/N ratios between Xe-133 and HM-PAO, IMP and HM-PAO were 0.50 and 0.63, respectively. T/N ratios varied from 39 to 137, and they may reflect tumor blood flows. In conclusion, HM-PAO SPECT may be a useful radiopharmaceutical for the evaluation of cerebral blood flow in patients with brain tumor and AVM. (author)