Differentiating diagnosis of WMLs

Question 1

MS Differential Diagnosis

Answer 1

No single clinical feature or test is sufficient

Question 2

What are the diagnostic criteria for MS?

Answer 2

1. Dissemination in space
2. Dissemination in time
3. Reasonable exclusion of alternative

Question 3

What is dissemination in space?

Answer 3

Two or more parts of CNS= in brain not always the same area

Question 4

What is dissemination in time?

Answer 4

Damage that occurs on different dates

Symptoms should not happen at the same time

Question 5

Why is misdiagnosis of MS an issue?

Answer 5

1. Often common conditions with non-specific symptoms, signs, MRI findings
2. NMOSD

Question 6

What does NMOSD stand for?

Answer 6

Neuromyelitis optica spectrum disorder

Question 7

What is NMOSD?

Answer 7

Inflammatory disorder of CNS characterised by severe, immune-mediated demyelination and axonal damage targeting optic nerves and spinal cord

Question 8

What are the clinical diagnosis of MS?

Answer 8

1. Age
2. Signs
3. Symptoms
4. CSF

Question 9

What are the MR diagnosis of MS?

Answer 9

1. Pattern
2. Shape
3. Enhancement
4. SWI
5. Other

Question 10

What are examples of pattern?

Answer 10

1. PV
2. Cortical
3. Sub-cortical
4. ON
5. CC
6. Spinal cord

Question 11

What are the shape of MS?

Answer 11

1. Oval

2. Dawson’s finger

Question 12

MR MS pattern: location

Answer 12

Immediately adjacent to PV, within cortex (cortical), below subcortical, Optic nerve, CC, Spinal cord

Question 13

MR MS pattern: shape

Answer 13

1. Oval

2. Dawson’s finger

Question 14

MR MS pattern: Enhancement

Answer 14

4-6 weeks, sometimes 3 months, usually 4 weeks

Question 15

MR MS pattern: SWI

Answer 15

CVS

Iron deposition

Question 16

Where do lesions develop?

Answer 16

Around the vein with the vein at the centre

Question 17

What are immediately adjacent to cortex?

Answer 17

U fibres

Question 18

What are the function of U fibres?

Answer 18

Connect one gyrus to another

Question 19

When do enhancing and non-enhancing lesions happen?

Answer 19

Enhancing: 3-4 weeks

Non-enhancing: much older

Question 20

In posterior fossa, where are lesions?

Answer 20

Along intermedullary course

Question 21

What are silent lesions?

Answer 21

Patients can have lesions not manifesting themselves clinically

Question 22

Where are focal demyelinated plaques found?

Answer 22

White matter

Question 23

Where are demyelinated lesions found?

Answer 23

Deep grey matter

Question 24

What would typically fit with an MS lesion?

Answer 24

If a lesion is observed that has a venule in its centre

Question 25

What does intralesional susceptibility signal represmet?

Answer 25

Iron-rich macrophages/microglia | Myelin loss also contributes

Question 26

What are spinal cord divided into?

Answer 26

1. Typical | 2. Atypical

Question 27

What are examples of typical for SC?

Answer 27

1. Unifocal | 2. Multifocal

Question 28

What are examples of Atypical SC?

Answer 28

1. Tumefactive | 2. Diffuse

Question 29

What are the pathology for NMO?

Answer 29

1. Inflammation 2. Astrocytopathy 3. Myelin relatively preserved

Question 30

What are the diagnosis of NMO?

Answer 30

Optic neuritis initial event in the young • Acute myelitis initial event in the older • AQP4 AB but negative 20-30%

Question 31

What is Aquaporin 4?

Answer 31

most abundant CNS water channel • concentrated in astrocytic foot processes

Question 32

What is astrocytopathy?

Answer 32

Conversion of antibodies to AQP4

Question 33

AQP4 Channelopathy

Answer 33

``` Female > 80% • Non-Caucasian predominance • Relapsing if untreated • Severe disability and high mortality • Associated with other auto-immunity • Onset with both ON + TM uncommon ```

Question 34

Myelin Oligodendrocyte | Glycoprotein (MOG)-AB Disease

Answer 34

``` Female : Male equal • No non-caucasian predominance • ~ 50% monophasic • Better outcome than AQP4-Ab disease • Not associated with other autoimmunity • Onset with both ON + TM common • Overlap with ADEM (monophasic & relapsing) ```

Question 35

What is SC lesion of NMO?

Answer 35

``` Extent > 3 segments • Central grey matter • Swelling • Partial enhancement • Atrophy & cavity formation ```

Question 36

What involved in neuromyelitis optica?

Answer 36

Preferential spinal central gray matter

Question 37

Specific brain lesions in NMO

Answer 37

Medullary periaqueductal grey | • Bilat hypothalamus

Question 38

Cloud-like enhancement

Answer 38

NMO - 90% | MS - 8%

Question 39

Cortical lesions

Answer 39

NMO- 0% | MS - 67%

Question 40

What is considered MS lesion?

Answer 40

If more than half of the lesions have a central vein

Question 41

Acute myelitis

Answer 41

Intramedullary lesions ≥ 3 contiguos segments (LETM) ≥ 3 contiguous segments SC atrophy (history of myelitis)

Question 42

Area postrema syndrome

Answer 42

Dorsal medulla/area postrema | lesions

Question 43

Acute brainstem syndrom

Answer 43

Periependymal brainstem lesions

Question 44

MOG-ab Similar to AQP4-ab

Answer 44

Conus involvement (isolated sphincter and erectile dysfunction) • Fluffy lesions (adults, or ADEM attacks childhood) • Bilateral cerebellar peduncle

Question 45

Best classifiers between MOG and MS

Answer 45

``` MS Ovoid lesions PV (body of lateral ventr) Dawson’s fingers T1 hypointense lesions •MOG Fluffy lesions 3≤ lesions (MOG AB) ```

Question 46

What pathology is not directly visualised?

Answer 46

Small vessel disease

Question 47

MR of SVD

Answer 47

``` White matter hyperintensities •Recent subcortical infarcts Lacunes •Microhaemorrhages •Perivascular spaces •Atrophy ```

Question 48

Where do WMH appear?

Answer 48

Vascular end zones | progress proximally along perforating arteries

Question 49

Where do lacunes appear?

Answer 49

WMH edge

Question 50

Where do WMH expand?

Answer 50

around lacune

Question 51

Perivascular spaces

Answer 51

● Fluid-filled spaces, follow typical course of a vessel, in GM/WM; SI similar to CSF As they follow the course of perforators, they are -linear when imaged parallel round or ovoid, when imaged perpendicular to the course of the vessel - <3mm

Question 52

Microbleeds

Answer 52

Small areas of signal void ● 2–5 mm in diameter, but up to 10 mm ● Associated blooming on T2*-w Perivascular collections of hemosiderinladen macrophages

Question 53

What are causes of micrbobleeds?

Answer 53

``` SVD (leakage) ● Cerebral amyloid angiopathy (CAA) Aβ amyloid deposition in vessel wall Cortical & leptomeningeal arteries, arterioles (veins) ```

Question 54

T2*-Microbleeds

Answer 54

``` Occur in the asymptomatic elderly (6.4%) Associated with hypertension, age, lacunes, confluent WMC • MS Absent • SVD Present • CADASIL Present ```