1. Imaging Degenerative Diseases of the Brain Cathleen Kouvolo

2. Alzheimer’s Disease Alzheimer’s Disease Parkinson’s Disease Parkinson’s Disease Huntington’s Disease Huntington’s Disease Pick’s Disease Pick’s Disease

3. Alzheimer’s Disease Most common cause of dementia Most common cause of dementia Defective processing of amyloid precursor protein Defective processing of amyloid precursor protein Affects hippocampus/parahippocampal cortex, cerebral cortex Affects hippocampus/parahippocampal cortex, cerebral cortex Dementia, anxiety, hallucinations, delusions, tremor Dementia, anxiety, hallucinations, delusions, tremor Dx is clinical; MR used to rule out other causes of dementia Dx is clinical; MR used to rule out other causes of dementia Tx: cholinesterase inhibitors; antidepressants/antipsychotics Tx: cholinesterase inhibitors; antidepressants/antipsychotics

4. Alzheimer’s – MR/CT CT- Diffuse cerebral atrophy, enlarged ventricles and widened sulci CT- Diffuse cerebral atrophy, enlarged ventricles and widened sulci T1 MR- Medial temporal lobe atrophy (amygdala, hippocampus, parahippocampal gyrus) T1 MR- Medial temporal lobe atrophy (amygdala, hippocampus, parahippocampal gyrus)

5. T1 weighted MR Control Alzheimer’s

6. Alzheimer’s – SPECT/PET SPECT- Temporoparietal hypoperfusion (especially in medial temporal lobes) SPECT- Temporoparietal hypoperfusion (especially in medial temporal lobes) PET- decreased glucose metabolism in frontal, parietal, temporal regions PET- decreased glucose metabolism in frontal, parietal, temporal regions

7. SPECT Alzheimer’s

8. Parkinson’s Disease Hypokinetic disorder Hypokinetic disorder Loss of dopaminergic neurons in substantia nigra (pars compacta) Loss of dopaminergic neurons in substantia nigra (pars compacta) Pill-rolling tremor, cog-wheel rigidity, bradykinesia, shuffling gait, mask-like facies Pill-rolling tremor, cog-wheel rigidity, bradykinesia, shuffling gait, mask-like facies Dx: clinical after other etiologies ruled out Dx: clinical after other etiologies ruled out Tx: levodopa/carbidopa, anticholinergics, amantadine; surgery for refractory cases Tx: levodopa/carbidopa, anticholinergics, amantadine; surgery for refractory cases

9. Parkinson’s – MR/CT Diffuse atrophy and enlarged ventricles seen on CT Diffuse atrophy and enlarged ventricles seen on CT Decreased pars compacta width (substantia nigra) may be evident on MR Decreased pars compacta width (substantia nigra) may be evident on MR

10. T2 weighted MR ControlParkinson’s

11. Parkinsons - PET FDG- Similar distribution of hypoperfusion to that of Alzheimer’s (temporoparietal region) FDG- Similar distribution of hypoperfusion to that of Alzheimer’s (temporoparietal region) Fluorodopa- Less uptake in pars compacta in severe clinical disease as compared to mild disease Fluorodopa- Less uptake in pars compacta in severe clinical disease as compared to mild disease

12. Huntington’s Disease CAG triplet repeat expansion in huntingtin (HD) gene CAG triplet repeat expansion in huntingtin (HD) gene Loss of spiny neurons, atrophy of striatum (especially caudate nucleus) Loss of spiny neurons, atrophy of striatum (especially caudate nucleus) Choreiform movements, ataxic gait, facial grimacing/lip smacking, dementia Choreiform movements, ataxic gait, facial grimacing/lip smacking, dementia Dx: MR and positive family history Dx: MR and positive family history Tx: supportive Tx: supportive

13. Huntingtons – MR/CT CT and T1 MR- caudate atrophy CT and T1 MR- caudate atrophy T2- increased intensity in caudate and putamen (due to gliosis); decreased intensity in globus pallidus (due to iron deposition) T2- increased intensity in caudate and putamen (due to gliosis); decreased intensity in globus pallidus (due to iron deposition)

14. CT ControlHuntington’s

15. Huntington’s - PET PET FDG- hypoperfusion of caudate nucleus PET FDG- hypoperfusion of caudate nucleus May be evident before MR or CT changes May be evident before MR or CT changes

16. Pick’s Disease Defect in tau protein Defect in tau protein Frontal and temporal lobes involved Frontal and temporal lobes involved Symptoms similar to Alzheimer’s disease, greater personality change as compared to memory loss Symptoms similar to Alzheimer’s disease, greater personality change as compared to memory loss Younger age of onset (compared to Alzheimer’s disease) Younger age of onset (compared to Alzheimer’s disease) Dx: MR Dx: MR Tx: Cholinesterase inhibitors not helpful, serotonergic agents may help with behavior Tx: Cholinesterase inhibitors not helpful, serotonergic agents may help with behavior

17. Pick’s – MR/CT CT- Frontotemporal atrophy CT- Frontotemporal atrophy MR- Sulcal widening, ventricular enlargement, widening on lateral sulcus (sylvian fissure), atrophy of insula, inferior frontal/superior. MR- Sulcal widening, ventricular enlargement, widening on lateral sulcus (sylvian fissure), atrophy of insula, inferior frontal/superior.

18. CT ControlPick’s

19. Pick’s - SPECT (Frontal variant) Hypoperfusion in ventromedial frontal region (Frontal variant) Hypoperfusion in ventromedial frontal region (Lateral variant) Hypoperfusion in one/both temporal lobes and anterolateral temporal lobe atrophy (sparing of hipppocampal formation)- left more affected than right (Lateral variant) Hypoperfusion in one/both temporal lobes and anterolateral temporal lobe atrophy (sparing of hipppocampal formation)- left more affected than right

20. SPECT Pick’s

21. Summary of Buzzwords Alzheimer’s- medial temporal lobe Alzheimer’s- medial temporal lobe Parkinson’s- substantia nigra Parkinson’s- substantia nigra Huntington’s- caudate nucleus Huntington’s- caudate nucleus Pick’s- frontotemporal lobes Pick’s- frontotemporal lobes

22. Resources University of Virginia: Introduction to Head CT; http://www.med- ed.virginia.edu/courses/rad/headct/index.html University of Virginia: Introduction to Head CT; http://www.med- ed.virginia.edu/courses/rad/headct/index.html http://www.med- ed.virginia.edu/courses/rad/headct/index.html http://www.med- ed.virginia.edu/courses/rad/headct/index.html Goetz: Textbook of Clinical Neurology, 2nd ed Goetz: Textbook of Clinical Neurology, 2nd ed Basic Clinical Neuroanatomy, Williams and Wilkins Basic Clinical Neuroanatomy, Williams and Wilkins Boards and Wards, 2 nd ed, Lippincott Williams and Wilkins Boards and Wards, 2 nd ed, Lippincott Williams and Wilkins