Target STROKE

Patient selection for endovascular

treatment

Prof. Flavio Ribichini

Divisione e Cattedra di Cardiologia

Università di Verona

TIME IS BRAIN

STEP 1: PRE-HOSPITAL CARE

• Recognition of stroke symptoms

• Advanced notification of the Stroke Team

• Referral to a Stroke Center

• Stroke network

STEP 2: PATIENT EVALUATION

• Clinical Examination: NIHSS mild/moderate/severe

• Laboratory Values

(glucose, creat, Hto, pH, Na, K)

• Medical History

STEP 3: IMAGING AND DIAGNOSIS

• Imaging CT/ MRI/ Cathlab

• Image Interpretation

• Patient triage at the scanner

Patient selection for endovascular

treatment

CLINICAL

IMAGING

Clinical assessment:

• Neurologic state previous to acute stoke

• Time from onset (difficult in wake-up stroke, and in

vertebro-basilar syndomes).

• Clinical extension according to NIH stroke scale

Independently of the treatment modalities, transfer to a

Stroke Unit has a strong impact on mortality (NNT 32

to save 1 life).

(Micieli G, et al.(2012) The role of emergency neurology in Italy: outcome of

a consensus meeting for a Intersociety position. Neurol Sci 33(2):297–304.)

NHI Stroke Scale

Mild stroke <4(no IVL)

Intermediate 4-20Needs Tx

Severe deficit >20Poor prognosis

CT Scan

NCT: non-contrast CT

CTA: CT angiography

CTP: CT perfusion imaging

Spiral CT

Contrast media

Image processing

Neuro-imaging assessment:

Infarct core and the Ischemic Penumbra

Threshold of ischemia

CBFCBF

50-60 ml/100 g/min normal

15-20 ” Neurological

dysfunction

<10 ” infarction

Ischemic

penumbra

+40 min

unclear time window => missmatch

+1.5 h

CTP: CT perfusion imaging

CTA: CT angiography

Selective angiography

Before stroke treatment

• Contraindications:

– Exclude bleed

– Extensive ischaemic damage at late stage

CT Imaging Recap

• Intensity measured in

Hounsfield Units (HU)

• Viewer converts a

window of HU values to

shades of grey

750/350 40/80 32/20

Early Ischaemic Damage

– Loss of grey/white matter differentiation

– Hypodensity of brain tissue

– Swelling

• Changes are very subtle in the first few

hours

Loss of Grey/White Differentiation

Healthy insulaDamaged insula

Loss of Grey/White Differentiation

• Reducing the window width will increase

contrast and make the comparison easier

• This image uses a window centred on 32 HU,

with a width of 20 HU

Healthy insulaDamaged insula

International guidelines

for patient selection for

endovascular treatment

• American Heart Association

• American Stroke Association

• European Stroke Organisation (ESO)

• European Society of Minimally Invasive

Neurological Therapy (ESMINT)

• European Society of Neuroradiology (ESNR)

ASPECTS is recommended in the

guidelines as one the essential

imaging criteria by:

ASPECTS- SCORE

10 MCA regions:

• C: Head of caudate nucleus

• I: Insula

• IC: Internal capsule

• L: Lentiform nucleus (putamen + globus pallidus)

• Cortical regions M1-M6

ASPECTS evaluation

Low score 0-4

High score

Mid score 5-7

8-10

Wake up stroke- Initial CT

“There is a dense thrombus within the proximal left MCA. There is

significant established ischemia within the left MCA territory with loss of

the insular cortex. There is also significant swelling within the

temporal, frontal and parietal regions with effacement of the sulci. The

appearances suggest significant established ischaemia with a proximal

MCA occlusion. There is no haemorrhage”

Registration and Segmentation

e-ASPECTS

Visual display of

ischemic

damageCT viewer with full

windowing and

measurement

controls

Summary of

ASPECTS score

and damaged

regions

Large mismatch area

24 h NIHSS = 1

CTP 24 h after EVT

CASE- Example

• left sided symptoms

• NIHSS 22

• Pre-CT delay 45 minutes

NCT

CTP

CLINICAL SELECTION

• NIHSS ≥10 or aphasic

• Beep:

-- Neurologist

-- Interventionist

– Anesthetist

– Cathlab

THE LONDON SOUTHENDS PATHWAY

Southends “one stop system”

Hemorrhagic or ischemic?Clot location?

Collaterals? To treat or not to treat?

The One-stop-system

One scan in the angio (60cc of iv-contrast)

Siemens

DynaCT

CT

CT vs. Dyna CT

105 min

75 min

45 min

30 min

15 min

00 min

Todays‘ standard The One-stop-option

Arrival

at hospital

Neurologic

exam

CT MR

CT Perfusion

ER

Angio

suite,

treatment

MR Perfusion

15 min

00 min Arrival

at hospital

Neurologic

exam

45 min

30 min

Angio

suite,

treatment

Angio

suite

Imaging

1h saved =20% better chance

for good outcome

(mRS ≤ 2)

high NIH

low NIH

IMAGE REVIEW “ON THE GO”

Instant e-mail notification

IMAGING SELECTION

• e-ASPECTS ≥6

• Major Vessel Occlusion

Endovascular treatment is the future goal for

acute troke treatment.

Time is an issue,

Reducing neuro-imaging time is clue

50

32

0

8-10 5-7 0-4

90 day outcome by ASPECTS

ASPECTS score

% P

ati

ents

wit

h g

oo

d o

ut

ou

tco

me