Imaging Findings Pertaining to Differential Diagnosis of Dementias
| Etiology of dementia | Regional deficits identified by neuronuclear imaging |
|---|---|
| AD | Parietal, temporal, and posterior cingulate cortices are affected early, with relative sparing of primary sensorimotor and primary visual cortices and sparing of striatum, thalamus, and cerebellum. In early stages, deficits often appear asymmetric, but degeneration eventually is evident bilaterally. |
| Vascular dementia | Hypometabolism and hypoperfusion affect cortical, subcortical, and cerebellar areas. |
| Frontotemporal dementia (e.g., Picks disease) | Frontal cortex and anterior temporal and mesiotemporal areas are affected earlier or with greater initial severity than are parietal and lateral temporal cortices, with relative sparing of primary sensorimotor and visual cortices. |
| Huntington’s disease | Caudate and lentiform nuclei are affected early, with gradual development of diffuse cortical involvement. |
| Parkinson’s dementia | Deficits are similar to those of AD, but with more sparing of mesiotemporal area and less sparing of visual cortex. |
| Dementia with Lewy bodies | Deficits are similar to those of AD, but with less sparing of occipital cortex and possibly cerebellum. |