Clinical evaluation of single photon emission computed tomography of the brain

Single photon emission computed tomography (ECT) was performed on 67 patients. ECT images were taken with a Shimadzu scintillation camera, LFOV-E, before a delayed scan. Eighteen of 67 patients showed abnormal findings on the ECT images. Fourteen of the 18 had a transmission X-ray CT (TCT) study as well. There were eleven cases with brain metastases, one case each of an old infarction, a skull metastasis, and a surgical wound. Eleven of fourtynine ECT-negative patients had a TCT study as well, and intracranial lesions were found in five. The smallest lesion found by ECT was 0.5 cm in diameter on the TCT image and the largest lesion missed by ECT was a tumor in the corpus callosum, measuring 4.2x2.7 cm. As far as the patients who also received TCT study are concerned, both the ECT and the ordinary scan were thought to be equal in sixteen patients and ECT to be superior in seven whereas the ordinary scintigram was superior in two. At present, ECT is considered to be useful when it is used in addition to the ordinary scans. In the field of clinical nuclear medicine, the development of new radiopharmaceuticals which are labeled with single photon emitters and which can show the metabolic activity of the brain is eagerly awaited. (orig.)