mri of multiple sclerosis and differential diagnosis
TRANSCRIPT
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MRI of Multiple Sclerosis
and Differential Diagnosis 2013 Regional MS Summit: 5/13/2013
Dean Shibata, M.D
Neuroradiology
Department of Radiology,
University of Washington
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• Normal Myelination & Normal Variants
• Classification of white matter disease
• Small vessel ischemic disease (leukoaraiosis)
• Developmental white matter disease
(leukodystrophy)
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• Multiple Sclerosis on MRI
Typical MRI features
Mag Transfer Imaging
Diffusion Tensor Imaging
Imaging DDx
• Other WM Diseases:
ADEM (Acute Disseminated Encephalomyelitis)
CPM (Central Pontine Myelinolysis)
PRES (Posterior Reversible Encephalopathy Synd)
PML (Progressive Multifocal Leukoencephalopathy)
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Normal
Myelination:
Birth
Osborn 1994
Dorsal Brainstem Int Cap Post Limb
Motor corticospinal tracts
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Normal
Myelination:
3 to 4 months
Int Cap Ant Limb
Corticospinal tracts
Osborn 1994
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Normal
Myelination:
6 to 8 months
Nearly adult
Osborn 1994
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Barkovich 1995 Barkovich 1995
4 months (T1)
Birth (T1)
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Barkovich 1995
8 months (T1)
12 months
Barkovich 1995
12 months (T2)
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Myelination in Development
• begins 5th fetal month (path)
• caudal to cephlad ¯ brainstem > cerebellum, BG > cerebrum
• dorsal to ventral ¯ occipital lobes > frontal lobes
• Rapid first 2 yrs, continues into
3rd/4th decades ¯ T1 relaxation changes continue into teens
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2 yo w DD 60 yo w MSΔ
Delayed Myelination Perivascular Spaces
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Corticopontine Tracts
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48 year old 1 year s/p
servere head trauma
Wallerian Degeneration
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Normal Vs Abnormal: WM bright on T2 or FLAIR
ALS, CPM, MS Corticopontine
tract
Posterior Limb
Internal
Capsule
MS Loose Myelin Frontal Horns
PVL, MS
PVWMSVD
Parietal
Association
tracts
Peritrigonal
WM
Location Structure DDx
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WM: Classification by Mech
• Primary demyelinating disease ¯ Multiple Sclerosis
• Secondary demyelinating disease ¯ Allergic
¯ Viral
¯ Vascular
¯ Metabolic
¯ Toxic
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WM: Classification by Mech
• Allergic (immunologic) ¯ Acute disseminated encephalomyelitis - ADEM
• Viral ¯ HIV-associated encephalitis
¯ Prog multifocal leukoencephalopathy - PML
¯ Subacute sclerosing Panencephalitis y – SSPE
• Vascular ¯ Binswanger’s disease
¯ Postanoxic encephalopathy
¯ Toxic
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1 3
5 7
2 4
6 8
White Matter Standards for Visual Scoring
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WM: Classification by Mech
• Toxic ¯ Radiation
¯ Marchiafava-Bignami Disease (Corpus Collosum)
¯ Disseminated necrotizing leukoencephalopathy
¯ Drugs (chemoRx, metamphetamine, cocaine)
¯ Toxins (triethyl, tin, lead)
• Metabolic ¯ central pontine myelinolysis (osmotic) - CPM
• Traumatic: Diffuse axonal shear injury - DAI
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WM: Classification by Mech
• Dysmyelinating Disease
¯ Adrenoleukodystrophy – Males, posterior, Pons/Medulla, Gad+
¯ Metachromatic Leukodystrophy (MLD) – cerebellum, spares subcortical U fibers and BG – tigroid WM
¯ Krabbe’s Disease – Ca++ BG
¯ Alexander Disease – Big head, Anterior
¯ Canavan’s Disease – Big head, NAA, stem/BG
¯ Pelizaeus-Merzbacher Disease (PMD) – tigroid WM
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Multiple Sclerosis: Imaging
• Abnormal MRI scans are found in:
¯ 90% of patients with definite diagnosis of MS
¯ 70% of patients with diagnosis of probable MS
¯ 30%-50% of patients with possible MS
• 3 criteria for the MRI diagnosis of MS
(Fazekas et al.):
¯ Lesions abutting the lateral ventricles
¯ Lesions with diameter greater than 0.6 cm
¯ Lesions present in the posterior fossa
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Multiple Sclerosis
• 85 % have ovoid perivent lesions (Dawson’s fingers)
• 50 to 90 % w “definite” MS have CC lesions
• 10% of adults have PF lesions
• Temporal lobe lesions are relatively specific for MS
• MS lesions generally lack mass effect
• Tend be darker and “punched out” on T1
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Multiple Sclerosis: McDonald Criteria for MRI
• Typical MS demyelinating lesions meeting at least 3 of the following 4 criteria:
¯ At least 1 Gd lesion or at least 9 T2 lesions
¯ At least one infratentorial lesion
¯ At least one juxtacortical lesion
¯ At least 3 periventricular lesions
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44 year old numbness
legs and feet
35 year old R body
numbness
R leg weakness
Dawson’s Fingers
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Flame shaped periventricular
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21 year old optic
neuritis
29 year “trouble
controlling R
side”body
Target Sign
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23 year old vague
parethesias 39 year old headaches
Which one is Multiple Sclerosis?
1 2
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23 year old vague
parethesias 39 year old
headaches
MS Mets
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Corpus Collosum
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Punched out lesions on T1W
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DDx: Corpus Callosum Lesions
• Tumors: GBM, Lymphoma, Lipoma
• Demyelinating Dz: MS, Marchiafava-
Bignami, PML
• Infarct (“rare”, dual arterial supply)
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24 year old lethargy p
respiratory illness 24 year old scattered
parethesias
Which one is Multiple Sclerosis?
1 2
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24 year old lethargy p
respiratory illness 24 year old scattered
parethesias
Histoplasmosis MS
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Tumefactive MS
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Tumefactive MS
PreGad PostGad
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21 year old blurred
vision
40 year old nausea &
dizziness
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21 year old blurred
vision
40 year old nausea &
dizziness
Mets MS
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Multiple Sclerosis: Advanced MRI
• Magnetization transfer imaging ¯ Decreased MTR (Mag Transfer Ratio) in MS
• MR Spectroscopy ¯ Decreased NAA in normal appearing WM
• Diffusion tensor imaging ¯ Decreased FA and increased MD in normal appearing WM
• High resolution grey matter imaging (7T) ¯ Tiny foci of GM on double inversion FLAIR at 7T in MS
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frequency
bound
free MT pulse
~2000 kHz
off-resonance
Magnetization Transfer
energy
transfer
saturation
effect
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T1 Pre Gad T1 Post Gad
MT MT No MT No MT
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Heide AC, Kraft GH et al, AJNR, 1998
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Heide AC, Kraft GH et al, AJNR, 1998
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Heide AC, Kraft GH et al, AJNR, 1998
Normal VEP Abnormal VEP
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J. Bellmann-Strobl et al, Eur Radiol 2009
Interferon Therapy Monitored in Normal Appearing WM with MRS
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J. Bellmann-Strobl et al, Eur Radiol 2009
Interferon Therapy Monitored in Normal Appearing WM with MTR
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Diffusion Tensor Imaging (DTI): Mean Diffusivity and Fractional Anisotropy
Free diffusion
Restricted diffusion
Isotropic diffusion
Anisotropic diffusion
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L2
L3
L1
Axial and Radial Diffusion: L1, L2, L3
Axial Diffusivity: L1 Radial Diffusivity: (L2+L3)/2 Mean Diffusivity: (L1+L2+L3)/3 FA:
222
222
3212
)31(3221
LLL
LLLLLL
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L2
L1
L3
Example
L1, L2, L3
TBSS
maps
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T Stat = -2.371
FLAIR lesion burden
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Time
Fractional Anisotropy (FA) change for patients on Tysabri
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1.5 vs 7T Imaging of intracortical lesions
Kollia K, et al, AJNR, 2009
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7T Imaging of intracortical lesions
Kilsdonk ID, et al, Brain, 2013
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ADEM: Acute Disseminated Encephalomyelitis
• “Monophasic” but often
variable enhancement
• Relatively little mass effect
• Deep grey (thalami)
common
• May have hemorrhage
• Subcortical (ADEM) Vs
calloseptal (MS)
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11 year old lethargy
hemiparesis
3 year old rapidly ↓
mental status
ADEM
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ADEM
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5 year old drowsiness
and seizure
ADEM
6 year old bilateral arm
and leg numbness
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9 year old 9 days of
L hemiparesis
ADEM
3 year old ↓ level of
conciousness
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CPM: Central Pontine Myelinolysis
• Transverse pontine fibers most severely
involved Vs corticospinal tract
• Extra PM in 50%
• >75% EtOH or hyponatremia correction
• DWI bright early, may enhance
• Variable resolution
• Spastic quadriparesis, pseudobulbar palsy
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CPM
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CPM
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Posterior Reversible Encephalopathy Syndrome (PRES)
• Most often caused by abrupt changes in blood pressure, seizures, or certain
immunosuppressive medications.
• Vasogenic edema predom in WM related to loss of autoregulatory ability
• Overall prognosis is good.
• DWI negative (Vs acute infarct cytotoxic edema)
• Usually in occipital, parietal, and temporal areas
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PRES
48 year old post
seizure 2 months later
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Hypertensive
Encephalopathy
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Hypertensive
Encephalopathy
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58 year old cardiac Tx
w Seizure
45 year old w impaired
vision
Which one is PRES?
1 2
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58 year old cardiac Tx
w Seizure
45 year old impaired
vision
PRES PML
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PML: Progressive Multifocal Leukoencephalopathy
• JC papovavirus
• Most commonly HIV or other
Immunocompromised
• Classically: WM “geographic” lesions
without enhancement or mass effect
• Formerly endstage HIV w poor
prognosis
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PML
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PML
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PML
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