DEMENTIA IMAGING

The imaging agent used is Tc-HMPAO.

The patterns to know are:

ALZHEIMERS - temporoparietal hypoperfusion; posterior cingulate hypoperfusion
- initially asymmetric, becoming symmetric in severe AD


FRONTOTEMPORAL DEMENTIA - frontal, temporal hypoperfusion

VASCULAR DEMENTIA - cortical, subcortical and cerebellar hypoperfusion

LEWY BODY DEMENTIA - occipital and parietal hypoperfusion

PARKINSONS - similar to AD but more occipital changes
- substantia nigra is seen to be absent on dopamine scans

HUNTINGTONS - basal ganglia (caudate & putamen)

ttk: the basal ganglia are in front, right next to the frontal lobes.


Things to know:
1. Anatomy
- the hardest thing to remember is whether the temporal or the parietal lobes are closer to the frontal lobes. Well, it's neither! Both are wedged like a 2-storey structure between the F and O lobes, with the (yellow) P being the 2nd storey.