The Application of Proton Magnetic Resonance Spectroscopy and Cerebral Perfusion Single Photon Emission Computed Tomography for the Diagnosis of Frontotemporal Dementia in Brothers
W Ki, YYP Lee, DLK Dai
Hong Kong J Radiol 2008;11:28-31
Extensive data have shown that magnetic resonance spectroscopy is valuable for the diagnosis of common dementias. Cerebral perfusion single photon emission computed tomography has proven characteristic perfusion defect patterns in patients with Alzheimer's disease and frontotemporal dementia. This report is of 2 brothers with frontotemporal dementia. The elder brother was diagnosed with frontotemporal dementia at the age of 57 years. Imaging studies showed that he had unilateral left frontotemporal atrophy by magnetic resonance imaging, depressed N-acetyl aspartate:creatine ratio and raised myoinositol:creatine ratio by magnetic resonance spectroscopy, and asymmetrical left frontotemporal hypoperfusion by cerebral perfusion single photon emission computed tomography. His brother presented with memory loss at the age of 48 years and was suspected to have familial inheritance of frontotemporal dementia. He had similar magnetic resonance spectroscopy pattern and single photon emission computed tomography findings, although no morphological changes were evident at routine magnetic resonance imaging brain study. These patients demonstrate that magnetic resonance spectroscopy is sensitive for early screening for dementia, and cerebral perfusion single photon emission computed tomography has the unique ability to differentiate frontotemporal dementia from Alzheimer's disease.