In 1982 Aaslid R introduced in literature Transcranial Doppler · In 1982 Aaslid R introduced in literature Transcranial Doppler - B-mode and colour Doppler US capabilities were added

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D'andria et al. WJ of Cardiology, 2016

Aaslid R et al, J Neurosurg 1982

TCD

In 1982 Aaslid R introduced

in literature Transcranial Doppler

- B-mode and colour Doppler US capabilities were added

to the conventional TCD in the late 1980s

- TCCD has emerged as a safe, cheap, non-invasive, fast, portable,

Bedside real time neuroimaging modality for the evaluation and follow-up

Monitoring of many neurological disease

TECNICHE D’ESAME

APPROCCIO TRANSTEMPORALEPIANO ASSIALE

PIANO CORONALE

APPROCCIO SUBOCCIPITALE

APPROCCIO TRANSORBITALE

Kirsch et al.

Radiology, 2013

Temporal and

suboccipital

windows

PIANO ASSIALEMESENCEFALICO

Vaso Patternscolorimetrici

Profondità di insonazione

MCA (M1) ROSSO 40-60 mm

ACA/MCA

Sifone-C1

ROSSO/BLU 55-65 mm

ACA (A1) BLU 60-80 mm

PCA (P1)

(P2)

ROSSO

BLU

55-70 mm

45-70 mm

TOP basilare ROSSO/BLU 60-70 mm

Finestra Transtemporale

The role of transcranial color Doppler

in cerebrovascular disease

The American Academy of Neurology states that TCCD main clinical indications include:

Ischaemic cerebrovascular disease - diagnosis and prognosis in acute stroke

and transient ischemic attack

- Carotid embolism (MES)

- paradoxical embolism (PFO)

- sickle cell disease

Neurointensive care - vasospasm and hemodynamic monitoring in haemorrhagic

strokes

- traumatic brain injury

- raised ICP

- brain stem death

Periprocedural application in carotid and intracranial vascular interventions

Sloan MA, Neurology 2004

Diagnosis in acute stroke and TIA

TCCD can identify:

- Acute MCA occlusion

sensitivity, specificity, PPV, NPV> 90%

- Occlusion of ICA siphon, Vertebral Artery and Basilar artery

Sensitivity and PPI 70-90%, high specificity

- Stenosis of intracranial vessels

specificity 100%, sensitivity 93%

Baumgartner pionered the use of TCCD for the detection of

intracranial stenosis and pubblished velocity-based criteria which

were correlated with DSA

Sloan MA, Neurology 2004

Baumgartner RW et al, Stroke 1999

D'andria et al. WJ of Cardiology, 2016

STENOSI INTRACRANICA

Accelerazione segmentaria del flusso con aliasing al color-doppler ed iperecogenicità in B-mode

Turbolenze del flusso nel punto di stenosi

Ridotta velocità a valle della stenosi

Power doppler aiuta ad evidenziare la stenosi

Controllo post fibrinolisi

stenosi ACM

US detection of intracranial

stenosis > 50%

PSV (cm/sec) sensibilità specificità

ACA >155 100% 100%

MCA >220 100% 100%

PCA >145 100% 100%

BA >140 100% 100%

VE >120 100% 100%

Baumgartner, Neurology 1999

OCCLUSIONE INTRACRANICA

Mancata rilevazione del vaso alla profondità e nella posizione caratteristiche mentre sono presenti tutti gli altri vasi

segni di compenso in altri distretti

E’ in genere un processo dinamico da seguire nel tempo, soprattutto in fase acuta

Native (ie, non–contrast enhanced) power-based TCCS depicting an MCA mainstem occlusion while the ipsilateral and contralateral A1 segments of the ACA, the ipsilateral and contralateral P1 segments of the PCA, and the contralateral M1 segment of the MCA are...

Gerriets T et al. Stroke 2000;31:2342-2345

Copyright © American Heart Association

TCCD: role of

compensatory

arteries

Good collateral flow

compensations

Favorable

outcome

Less

Recurrence

Risk

Fang et al, BMC Neurology 2016, Liu LP et al,CNS Neurosci Ther 2014

A recent Chinese Consensus statement on the evaluation and intervention

of collateral Circulation acknowledged the superiority of TCCD.

Prognosis in acute stroke

Baracchini C, Stroke 2000

Sloan MA, Neurology 2004

- TCCD evidence of complete intracranial arterial occlusion

predicted worse neurological outcome, disability or death after 90 days

- Normal TCCD finding instead predicted early neurological improvement

- Clinical course of stroke may present either spontaneous improvements

or worsening in relation to dynamic changes in cerebral flow

The role of transcranial color Doppler

in ACUTE STOKE

Stolz E, Stroke 2008

Alexandrow AV, Circulation 2001

REOPENING of occluded

vessel within 6 h better clinical prognosis at 48h

OR 4,31 95% CI (2,67-6,97)

better functional status at 3 mo

OR 6,75 95% CI (3,47-13,12)

IMPROVEMENT <30 min better early outcome

EARLY REOCCLUSION

after thrombolisis

Worse outcome

Reduction of survival

Daily TCCD examination can be useful to recognize dynamic

changes in cerebral circulation

Diagnosis and prognosis in transient ischemic attack

1823 patients, 8,8% intracranial stenosis, cardiovascular events at 12 mo

7% in IC stenosis vs 2,4%

176 patients, 9,2% intracranial stenosis

Graded risk of new vascular events based on

ECD and TCD findings

Holzer, BMC Med Imaging 2009

Limiti dell’ecocolorDoppler transcranico:

- Scarsa finestra acustica

- Esame tecnicamente complesso per cui vi è la

necessità di:

accurata formazione,

strumentazione adeguata,

tempistiche di esecuzione adeguate

MEZZI DI CONTRASTO

Nei pazienti con cattiva qualità della

finestra acustica temporale (5-20%,

soprattutto donne anziane)

Se il paziente è candidato ad intervento di

tromboendoarterectomia

Se il paziente è candidato alla terapia con

rTPA

MEZZI DI CONTRASTOlimite

La breve emivita implica la necessità di eseguire l’esame rapidamente

MEZZI DI CONTRASTOcome eseguire l’esame

- diminuire la PRF

- Ridurre i guadagni del Color per ridurre gli artefatti

- Con la potenza degli ultrasuoni le microbolle risuonano e si rompono aumentando ulteriormente gli echi di ritorno

- Aumenta di 20 dB l’intensità del segnale

MEZZI DI CONTRASTOtecniche di utilizzazione

1) mdc in bolo con impiego di basse potenze e basso indice meccanico (esame real-time):

Studio dei VASI DI CALIBRO MAGGIORE

Finestra temporale

Piano mesencefalica

Senza mdc

dopo mdc

MEZZI DI CONTRASTOtecniche di utilizzazione

2) Elevati indici meccanici con basa velocità di emissione degli impulsi e basso frame-rate (1-2 Hz), immagine che deriva dalla distruzione delle bolle nel microcircolo:

studio della PERFUSIONE TISSUTALE

Study of Perfusion in acute stroke

- TCCD with the use of contrast medium

Perfusion Imaging of the cerebral microvasculature estimate the size

of the infarct and ischemic penumbra

- Many studies have done on clinical uses of Ultrasound Perfusion Imaging in

Stroke with agreement with MRI

Liu LP CNS Neurosci Ther 2014

Weisman M, Stroke 2000

Kern R, J of Cerebral Blood flow Met 2014

Seidel, Cerebrovac Disease 2009

SONOTROMBOLISI

Doppler continuo aumenta la ricanalizzazione

indotta da rTPA

Aumenta il legame di rTPA con la fibrina

Aumenta il trasporto del farmaco

Provoca una alterazione reversibile della

struttura della fibrina

L’effetto aumenta con il mdc (cavitazione

acustica delle microbolle)

CLOTBUST, Alexandrov 2004

Sonotrombolisi con microbolle

t-PA

microbolle

ultrasuoni

Sonotrombolisi con microbolle

Sonotrombolisi con microbolle

Sonotrombolisi con microbolle

Stroke, 2017

TCCD or TCD - diagnosis of temporary right-left shunting: PFO

-agitated saline solution intravenously injected

-micro-bubbles detection in cerebral circulation at rest and during Valsalva

strain

-Duration of Valsalva did not show a significant influence (P> 0,50)

- Single MCA or both: no significant difference in sensitivity (P= 0,15)

European Consensus Conference ESNCH, Venezia 1999

D'andria et al. WJ of Cardiology, 2016

Kerut EK, J Am Cardiol 2001

The entity of right to left shunt is directly associated with risk of stroke

D'andria et al. WJ of Cardiology, 2016

Sastry, J Clin Ultrasound, 2008

Cut off :15 HITS

100% sensitivity and

specificity vs TEE

TCCD accurancy

The role of transcranial color Doppler

in cerebrovascular disease

Why TCCD has to be included in a standard imaging

protocol in Cerebrovascular Events?

- It gives complentary information on cerebral vasculature

and haemodynamic pattern

- It allows bedside follow-up and monitoring in dynamic

conditions such as intracranial occlusions and strokes

- It give informations about etiology

of cerebrovascular events

- L’utilizzo del mdc favorisce il superamento del limite

della finestra acustica, aggiunge nuove informazioni

e indicazioni diagnostico-terapeutiche

Grazie per l’attenzione..

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