The role of brain single photon emission computed tomography in the diagnosis of primary progressive aphasia

We present two cases of primary progressive aphasia studied with neuropsychologic measures, computed tomography or magnetic resonance imaging, and single-photon emission computed tomography with technetium Tc 99m-labeled hexamethyl-propyleneamine oxime. Clinical and neuropsychologic observations revealed a marked, progressive loss of language functions over time with relative preservation of nonlanguage cognitive functions in both patients. The brain single-photon emission computed tomographic scan revealed marked left frontal and minimal left temporal and parietal hypoperfusion in case 1 and marked left posterior frontal and minimal left temporal hypoperfusion in case 2. The value of brain single-photon emission computed tomography in distinguishing primary progressive aphasia from Alzheimer's disease is described.