dskfnm 2015, copenhagen · ct and mri in dementia the new and the old prof. elna-marie larsson, md,...
TRANSCRIPT
E-M Larsson, 2015-01-29 15-01-25
1
CT and MRI in dementia: The new and the old
Prof. Elna-Marie Larsson, MD, PhD Section of Neuroradiology, Department of Radiology
Uppsala University, Akademiska sjukhuset Uppsala, Sweden
DSKFNM 2015, Copenhagen
• Normal aging vs dementia
• Morphology: atrophy, ischemia, infarcts
• Physiology: Diffusion MRI incl DTI, perfusion-MRI, (MRS, fMRI), PET/MRI
E-M Larsson, 2015-01-29 15-01-25
2
NORMAL AGING VS DEMENTIA
Ventricles and sulci, 61 healthy individuals, 30-86 years
Ventricles 30-79 years 30-86 60-86 80-86 Sulci 30-79 years 30-69 40-86 60-86
Övre gräns för Grad 1 Grad 2 Grad 3 Grad 4
Salonen, Neuroradiology 1997
E-M Larsson, 2015-01-29 15-01-25
3
Normal aging - dementia
• Gradual transition with overlap
• Old individual may have widening of sulci and ventricles. Fast progression of parenchymal reduction supports diagnosis neurodegenerative dementia disorder
• Young individual (<40-60 years) should not have widening of sulci and ventricles
Dementia classification
• Neurodegenerative dementia: e.g. Alzheimer’s disese (AD) 50%, Lewy body dementia 15-20%, frontotemporal dementia (FTD) 15%
• Vascular dementia 10%
• Secondary dementia 5-10% e.g. normal pressure hydrocephalus (NPH), brain tumour
E-M Larsson, 2015-01-29 15-01-25
4
Suspected dementia: What do we need in the clinics and for research?
• Early diagnosis
• Evaluation of treatment response
Radiology in the evaluation of dementia
CT or MRI can
• Exclude ”surgical” lesions (tumour, NPH, chronic SDH)
• Detect infarction/extensive ischemia (vascular dementia)
• Support clinical suspicion of degenerative dementia, differentiate between different types
MRI > CT, but CT is very useful as basic exam
E-M Larsson, 2015-01-29 15-01-25
5
Standardized terminology New ”lexicon” for the definition of Alzheimer’s disease (AD) (Dubois et al 2010):
• Clinical diagnosis: - Preclinical AD (asymptomatic ”at risk” with CSF or imaging amyloid biomarkers, presymptomatic with mutations) - Prodromal AD (”pre-dementia”) AD with CSF or imaging (FDG or amyloid PET, MTA on MRI) biomarkers - AD (dementia)
• Neuropathological diagnosis: ”AD pathology” (microscopic tissue diagnosis)
Clinical suspicion of AD: Imaging biomarkers play an increasing role
Small et al, Lancet, Neurology, 2008
E-M Larsson, 2015-01-29 15-01-25
6
MORPHOLOGY
Morphology
1. Sulci and ventricles
2. Medial temporal lobe atrophy: MTA scoring (Scheltens scale)
3. White matter ischemia, infarcts
4. Lesions: tumor, normal pressure hydrocephalus, posttraumatic changes
E-M Larsson, 2015-01-29 15-01-25
7
Demens CT / MR utlåtande
.
Läkartidningen 47/2013
GCA 0 1 GCA 2 3 (bifrontally)
Global cortikal atrophy (GCA)
Wahlund et al, Läkartidningen 47/2013
E-M Larsson, 2015-01-29 15-01-25
8
Difference between a group of AD-patients and a group of healthy controls (light blue is most severe). Simmons et al 2009
Cortical thickness
E-M Larsson
Hippocampus
Alzheimer’s disease Normal
E-M Larsson, 2015-01-29 15-01-25
9
Duara, Neurology 2008
Red = hippocampus Blue = entorhinal cortex Green = perirhinal cortex
Right medial temporal lobe Hippocampus is blue
Visual scoring of medial temporal lobe atrophy (MTA)
Scheltens et al. J Neurol 1995;242:558
E-M Larsson, 2015-01-29 15-01-25
10
www.radiologyassistant.nl
Coronal''slice'through'the'le0'medial'temporal'lobe'
www.radiologyassistant.nl
E-M Larsson, 2015-01-29 15-01-25
11
Age (years)
MTA 0 1 2 3 4
<70 (75) Normal Normal
70-80
Normal
Normal Normal
>80 Normal Normal Normal Normal
Medial temporal lobe atrophy – visual scoring
Adapted from Cavallin et al, Acta Radiol 2012
Medial temporal lobe atrophy
Wattjes et al, Radiology 2009
Grade 0 1 2 3 4
The temporal horns are usually not dilated in normal aging
E-M Larsson, 2015-01-29 15-01-25
12
2009 2014
2014 FT
FTD
Visual scoring of medial temporal lobe atrophy vs hippocampal volumetry
E-M Larsson, 2015-01-29 15-01-25
13
CT
75-year-old woman with Alzheimer’s disease
CT
Three subtypes of AD – automatic analysis of grey matter volume loss (Whitwell et al, Lancet Neurology 2012)
E-M Larsson, 2015-01-29 15-01-25
14
White matter hyperintensities
Wattjes et al, Radiology 2009
Minimal moderate extensive Fazekas 1 2 3
T1
T2 FLAIR
Vascular dementia
E-M Larsson, 2015-01-29 15-01-25
15
87-year-old woman with NPH
Thesis Johan Virhammar 2014
E-M Larsson, 2015-01-29 15-01-25
16
Thesis Johan Virhammar Thesis Johan Virhammar 2014
NPH
• Clinical triad
• CT without contrast agent: morphology, transependymal fluid transsudation
• MRI : as CT + exclude aqueduct stenosis or tumour, detect hyperdynamic flow through the aqueduct
• CSF tap test and/or lumbar infusion test
E-M Larsson, 2015-01-29 15-01-25
17
Radiologial findings in NPH
• Dilated ventricles (Evans index>0.3) including temporal horns
• Effaced parietal sulci parasagittally and on high convexities
• Often wide Sylvian fissures, focal dilatation of sulci, often periventricular transudation of fluid
• Increased flow velocity through the aqueduct (”flow-void” on MR), not pathognomonic
• (Decreased cerebral blood flow and cerebral blood volume)
AJNR Dec 2014
NPH
E-M Larsson, 2015-01-29 15-01-25
18
J Neurosurg 2014
PHYSIOLOGY: MRI, PET/MRI
E-M Larsson, 2015-01-29 15-01-25
19
Physiological MRI in dementia
• Diffusion- MRI incl. DTI
• Perfusion-MR
• (MRS)
• (fMRI)
• PET/MRI
Diffusion MRI
• Diffusion weighted imaging (DWI): 3 directions
• Diffusion tensor imaging (DTI): at least 6 directions. Reconstruction: tractography
• Diffusion kurtosis imaging (DKI): several b-values, 15 directions
E-M Larsson, 2015-01-29 15-01-25
20
DTI tractography
Corpus callosum (streamlines)
DTI tractography ROI left cingulum
E-M Larsson, 2015-01-29 15-01-25
21
DTI tractography Track left cingulum
Oblique view
Straight lateral views
Fischer, JMRI 2012
MD in Healthy control mild AD
E-M Larsson, 2015-01-29 15-01-25
22
Santillo et al 2013
Dementia with progressive aphasia
DSC perfusion: rCBF MRI
Perfusion MRI
E-M Larsson, 2015-01-29 15-01-25
23
CT
FDG PET
FTD – primary progressive aphasia
Pseudo continuous arterial spin labeling perfusion MRI (pCASL)
Perfusion method ideal for repeated measurements • No contrast agent • No ionizing radiation • Short scan time (5 min)
Imaging Volume
Labeling volume
E-M Larsson, 2015-01-29 15-01-25
24
MRM 2014
Alsop et al 2014
E-M Larsson, 2015-01-29 15-01-25
25
Wang et al 2013
Musiek, 2012
Direct comparison of FDG-PET and ASL MRI in AD
E-M Larsson, 2015-01-29 15-01-25
26
Cognitive reserve
Stern, Lancet Neurology 2012
Biomarkers of early AD (Neuroimaging and CSF)
• Measures of neurodegeneration (MRI: grey matter volume loss, diffusion and perfusion changes FDG-PET: decreased glucose metabolism)
• Amyloid-beta deposition in the brain (PET)
PET/MRI
E-M Larsson, 2015-01-29 15-01-25
27
Ann Neurol 2004;55:306–319
AD
Healty control
Jack et al 2014
E-M Larsson, 2015-01-29 15-01-25
28
sequential is now simultaneous.
Courtesy of Siemens
Sweden’s first PET/MRI scanner
Uppsala 2014 3T GE
E-M Larsson, 2015-01-29 15-01-25
29
Dementia work-up in clinical radiology
• CT of the brain is very helpful
• MRI is better and should always be done in young patients (< 65 years)
• FDG-PET is an excellent method
• PET-CT provides combined information
Dementia research
• MRI with morphological and physiological techniques
• PET
• PET/MRI
E-M Larsson, 2015-01-29 15-01-25
30
Thank you
Scandinavian network for standardization of MRI and CT in dementia and for potential research collaboration. 2-3 meetings/year in Scandinavia. Contact person: Eric Westman, Karolinska Institute, Stockholm [email protected]
E-M Larsson, 2015-01-29 15-01-25
31
ISMRM Nordic Chapter & DSMMR joint MR meeting - ”MRI from head-to-toe”
Topics: The expanding role of MRI in radiation therapy, Multiple Sclerosis and Cardiac MRI
www.ismrm.org/nordic or www.ismrm.dsmmr.dk