The Role of the Radiographer in Stroke Management

By: Fathima Hasan Mohamed

Senior Radiographer

Al Ain Hospital

22/08/2016 

Outline-Learning Points

• Stroke definition and classification.• Warning signs of stroke.• The role of the radiographer in early

intervention of acute stroke. • The Acute Stroke Pathway in Al Ain Hospital.• How diagnostic brain imaging guides therapy.

Introduction• Stroke is a medical emergency in which there is an

interrupted blood supply to the brain and brain cells begin to die.

• Stroke is one of the leading causes of death worldwide and one of the most common causes of long-standing disability

• Every second counts when experiencing a stroke, and the sooner the medical treatment begins the better the chances of survival and recovery.

•

Introduction

• TIME IS BRAIN : Stroke destroys two million brain cells every minute

Introduction

• Hundreds of lives could be saved each year if more people knew that stroke is a medical emergency.

Warning signs of stroke

The F.A.S.T. acronym was created as a helper for people to remember the main warning signs of stroke so that they can act immediately in the case of a stroke by dialling 999

F.A.S.T. stands for:

F – Face – has their face fallen on one side? Can they smile?

A – Arms – Can they raise both arms and keep them there?

S – Speech – is their speech slurred?

T –Time to call 999 if you spot any single one of these signs.

When stroke strikes, act F.A.S.T.

F.A.S.T. can help you to rapidly recognize when a stroke is taking place and then act quickly to get medical treatment and prevent serious damage

Stroke Classification

• Broadly can be two main types:• 1. Ischaemic Stroke - triggered by a clot

narrowing or blocking a blood vessel to the brain causing the area of brain supplied by that vessel to be starved of oxygen, leading to the death of brain cells.

Stroke Classification

• 2. Haemorrhagic Stroke (or Primary Intracerebral Haemorrhage) - triggered by the bursting of blood vessels leading to bleeding into the brain which causes damage.

Stroke Classification

• Transient Ischaemic Attack(TIA):• Sometimes defined as a minor stroke• Blood supply to the brain is temporarily

disturbed, leading to stroke like symptoms, but where the symptoms resolve within 24 hours. The cause of TIA is the same as the cause of ischaemic stroke.

The Radiographer Role-Early Intervention

• Radiographers are a vital part of the specialist stroke care team.

• Patients with acute brain attack require rapid access to high quality and appropriate imaging in order to diagnose the type of stroke.

• to allow for early intervention, such as thrombolysis, which has been shown to significantly improve patient outcome if administered within three hours.

• Patients who suffer a Transient Ischaemic Attack (TIA)- high risk of suffering an ischaemic stroke- require urgent imaging after appropriate assessment- ensure reduced morbidity.

The Radiographer Role- Early Intervention

• These patients also require follow up imaging, either by Computed Tomography (CT) or Magnetic Resonance (MR) in order to assess the efficacy, and/or options for further treatment.

The Radiographer Role- Early Intervention

• Radiographers undertaking this work not only have highly specialist skills in imaging modalities, but are experienced in the care and techniques required for scanning acutely ill patients who require urgent assessment during a critical period of the care pathway.

• Additionally, they may also have the advanced practitioner skills to review and report the images obtained to help facilitate rapid access to thrombolytic therapy by the stroke care team, or neurosurgical

review, within the short timescale required.

The Radiographer Role- Early Intervention

They may also be able to undertake the further imaging techniques such as CT Angiography and CT perfusion imaging. There will also be a need for MR scanning, specifically for TIA including Diffusion Weighted Imaging (DWI), MR perfusion, and, in addition, Magnetic Resonance Angiography (MRA), Contrast Enhanced MRA (CEMRA) if appropriate, and depending on local protocols .

Image interpretation and further imaging requirements

• Interpretation of the images needs to be both rapid and accurate.

• This may be achieved using a variety of options involving neuroradiologists, appropriately skilled stroke physicians or the use of tele-radiology.

• A better solution may be suitably trained, competent and authorised advanced practitioner radiographers to provide both imaging and reporting.

• It should be noted that postgraduate courses in interpretation of head CT images have existed for some years and CT head reporting by radiographers is considered normal practice in many imaging departments.

Al Ain Hospital-Acute Stroke Pathway

• Al Ain Hospital opened a stroke unit on November 2007 the first of its kind in the UAE offering a comprehensive multimodality stroke imaging service and enhanced treatment to people suffering from strokes.

Al Ain Hospital-Acute Stroke Pathway

• The doctors at Al Ain Hospital are experts in treating stroke patients and can quickly and effectively assess whether a patient is having a stroke, type of stroke, and determine viable treatment options for specific circumstances.

• Stroke team skilled staff and state-of-the-art facilities can assure everyone to receive some of the best care available in UAE.

Al Ain Hospital- Acute Stroke Pathway

• Six qualified Competent Neurologist are available for the Stroke patients. Each patient admitted to the Stroke Unit will be assessed by neurologist within 12 hours from admission and the plan of management will be started from the time of admission.

• Multidisciplinary team(MDT) consist of Rehabilitation , Neurologist , Nurses ,Speech therapist, Neuropsychology ,Dietician Case management ,Social workers &clinical pharmacists ED team.

Al Ain Hospital- Acute Stroke Pathway

• In Al Ain Hospital physicians are available to evaluate

imaging studies 24/7 basis.• Our department has highly qualified Consultants as

well as Radiologist Specialists available in-house 24/7 for urgent neuroimaging studies.

• Our physicians are experienced in interpreting head CT and brain MRI studies.

• They must be available to read these scans within 20 minutes of their completion.

Al Ain Hospital- Acute Stroke Pathway• Because of the need for the performance of a CT scan within

25 minutes Radiology department provides an in-house technologist capable of performing a CT scan and any CT-based studies.

• Al Ain hospital provides minimum of 4 certified radiology technologist trained in CT techniques- in-house on a 24/7 basis.

• As a requirement for comprehensive stroke unit for performing MRI studies on a 24/7 basis a qualified MR technologist is available (but not always in-house) on a 24/7 basis.

• Technologist will be at the hospital within 30 minutes after receiving a call from hospital if he/she is not available at hospital.

Al Ain Hospital- Acute Stroke Pathway

• A similar requirement applies to technologists needed to perform a cerebral angiogram.

• U/S and various cerebral perfusion studies are commonly elective based on the availability of technologists.

Al Ain Hospital- Acute Stroke Pathway

• Al Ain hospital provides minimum of 4 certified radiology technologist trained in CT techniques.

• CT technologist is available in-house on a 24/7 basis .• All CT technologist were trained to perform stroke

imaging protocols including : • Non contrast CT head , • CT cerebral perfusion, • Fast angiogram of head and neck.•

Al Ain Hospital- Acute Stroke Pathway

• To optimize our services further in order to minimize delay for stroke patients starting 2 years back all radiographers are trained and competent to perform a non-contrast CT head scan.

• They are required to maintain their competency and are re-evaluated every 3 months.

• Therefore during on call hours they will start to do the non-contrast CT head for acute stroke patients.

Al Ain Hospital- Acute Stroke Pathway

• Radiographer role extension: common in countries like UK.

• Practice whereby radiographers adopt duties that were previously only within the scope of the radiologist.

• Motivation for general radiographer – acquiring new knowledge and technology.

Al Ain Hospital- Acute Stroke Pathway

• Recent achievement in al Ain hospital is newly developed stroke code.

• Stroke code will be announced once acute stroke patient reaches ED.

• The code will only be heard on the phones in the Emergency Department, Radiology and the Stroke Ward. SMS sent on mobile phone.

• Mock “Stroke” drills are periodically carried out to ensure that time frames are met in acute stroke management.

Al Ain Hospital- Acute Stroke Pathway

Al Ain Hospital-Acute Stroke Pathway

• Al Ain Hospital has an integrated system with the community paramedics/Ambulance.

• There is an LCD screen in the ED Triage area connected to EMS wirelss system to receive pre-arrival notification and ED staff will call the CT technologist to keep the CT room ready upon patient arrival.

Al Ain Hospital-Acute Stroke Pathway

• The window time for acute stroke in Al Ain Hospital is 4.5 hours.

Al Ain Hospital-Acute Stroke Pathway

• The stroke management time in AAH?• Door to Triage Emergency 0-5,• Door to ED doctor less than 10 min, • Door to physician on call/stroke team 15 min, • Door to CT scan completion less than 25 min &Door to CT

scan interpretation less than 45 min• Door to rtPA less than 60 min, • Admission to stroke unit or ICU Done ASAP (by passing

admission office) less than 3 hours.•

How Imaging guides therapy• Computed tomography scanning in Al Ain Hospital is

a state-of-the-art medical imaging technology essential for acute stroke imaging and other neurological and spinal procedures.

• This system is capable of fast rotation times resulting in more rapid scanning and less time for patients to spend in the machine in addition delivering significant improvement of image quality and increment in isotropic resolution.

• Al Ain Hospital has a state of art Siemens Definition dual source 64 slice CT scanner as well as GE 64 slice scanner.

The three most crucial diagnostic questions in stroke to be answered by our state of the art CT

• Is the stroke caused by bleeding?by using a non-contrast CT scan to detect if the stroke is caused by hemorrhage or ischemia we can determine the potential benefit or harm of thrombolytic drugs.

Non-enhanced CT scan shows slight hypoattenuation of the right basal ganglia

3-Acute stroke (2 hours evolution) in a 46-year-old man with left hemiparesis

How Imaging guides therapy

• What is the size and location of the clot?When planning interventional clot retrieval, the size of the clot may be overestimated on axial CTA source images. The CT Neuro Engine and syngo.CT Dynamic Angio can help you better characterize the occlusion length and collateral status. Also visualization of contrast flow from the arteries to the veins enable a dynamic evaluation so we can see ante grade and delayed collateral blood flow.

Axial and coronal MIP reformatted CT angiographic images show obstruction of the right MCA and right carotid artery

Volume-rendered and curved reformatted images show significant stenosis of the right internal carotid artery

How Imaging guides therapy• How big is the infarct?

It takes just five simple steps to see the core infarct and penumbra.

• The guided workflow in syngo. CT Neuro Perfusion facilitates a routine 24/7 operation.

• Tissue at risk can be easily visualized in 3D color maps, based on the mismatch between cerebral blood volume (CBV) and cerebral blood flow (CBF). There is also Possibility to define a custom mismatch based on parameters we select.

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Perfusion CT show 70% mismatch in the right frontotemporal region and basal ganglia

MTT CBF CBV Summary map

How Imaging guides therapy

CT perfusion (CTP) is a tool that has been successfully employed to assess the extent of salvageable tissue

It is important to understand the meaning of potentially salvageable tissue

Whenever there is a decrease in the flow of blood to a particular area of the brain collateral supply from the leptomeningeal vessels and from normal surrounding vessels tries to compensate

This results in a central area, the infarct, which receives little or no blood supply and a larger peripheral area where autoregulatory compensation tries to ensure the maintenance of adequate blood supply.

This peripheral area is potentially salvageable by thrombolytic therapy and is called the ‘penumbra.’

CTP ProtocolPerfusion CT is performed by monitoring only the first pass of an iodinated contrast agent bolus through the cerebral circulation

Motion artifact is the main challenge in many acute stroke patients since sedation is frequently not possible but immobilization of the patient’s head can limit motion

continuous cine imaging for 45 secondsover the same slab of tissue (1–32 sections)dynamic administration of a small (50-mL)high-flow contrast material bolus with injection rate of 4–5 mL/sec

No need to check the createnin level in acute SP (neuron over nephron)

How Imaging guides therapy

How Imaging Guides therapy• MRI in Al Ain Hospital

• Al Ain Hospital successfully upgraded its old MRI machine GE 1.5 Tesla (LX horizon) to GE 1.5 tesla (HD23) in December 2013.

• With this new version of MRI machine and advances in hardware and software our MRI has the capability to perform advance imaging in evaluation of acute stroke which can be achieved by using a combination of conventional and more advanced imaging such diffusion and perfusion weighted imaging as well as high resolution MR Angiography techniques.

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How Imaging guides therapy

• Plus the addition of other new sequences like SWI (Susceptibility-weighted image) and SWAN (Susceptibility-weighted angiography) -T2 Star-Weighted angiography volumetric 3D acquisition technique that is sensitive to differences in susceptibility between different tissues help us to enhance the evaluation of acute ischemic stroke.

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Radiological approach to acute stroke patients

• 1-Once ED activated the stroke code, the radiologist and experienced CT technologist receives an sms on mobile or via operator on landline in CT.

• 2- Radiologist immediately informs firstly the trained radiographer who is available 24h/7 day to perform non contrast CT examination. Aim is to rule out IC hemorrhage

• 3- Radiologist also immediately informs the experienced CT technologist by telephone regarding acute stroke patient within window hour

• Experienced CT technologist who is either available in the house or if not he has to be present within 15 min to perform more advanced imaging like CTA and CTP if it is needed.

• 4- Report has to be generated within 20 min after completion of CT scan. KPI to be met.

• 5- Upon request in special circumstances urgent MRI with MR perfusion shall be performed.

Summary• Imaging is vital in helping to identify the causes of acute

stroke.• Definitive diagnosis- undertaken initially by CT brain

scanning.• effective treatment, which is very different, depending on

the type of stroke diagnosed, cannot be commenced until imaging and interpretation of these scans has taken place.

• The importance of the radiography workforce,• therefore, cannot be overestimated.• AAH will be undergoing the German Stroke Accreditation on

8 November 2015.

Thank you for your attention !

Fathima Hasan Mohamed Clinical Imaging Institute

Al Ain Hospital 3 November 2015

References

• 1. Choksi V, Quint DJ, Maly-Sundgren P, Hoeffner E. Imaging in Acute Stroke Applied Radiology 2005; 34 (2): 10-19• 2. Rowley HA. The four Ps of Acute Stroke Imaging: Parenchyma, Pipes, Perfusion and Penumbra. American Journal of

Neuroradiology 2001; 22: 599-601• 3. Wardlaw JM, Murray V, Berg E et al Thrombolysis for acute ischaemic stroke • Cochrane Database of Systematic Reviews 2009; (4) cd0002 13• 4. The Department of Health. Implementing the National Stroke Strategy – an imaging guide. London, DH: 2008• http://www.csnlc.nhs.uk/uploads/files/stroke/documents/national_documents/dh_085145.pdf• 5. National Institute for Health and Care Excellence (NICE) Diagnosis and initial management of acute stroke and transient

ischaemic attack (TIA). NICE CG 68: 2008. • http://www.nice.org.uk/guidance/cg68. National Stroke Association.• 6. Transient Ischemic Attack TIA: Prognosis and Key Management Considerations• http://www.stroke.org/sites/default/files/resources/tia-abcd2-tool.pdf• 7. Royal College of Physicians, Stroke Improvement National Audit Programme (SINAP) Combined Quarterly Report 2013• https://www.rcplondon.ac.uk/sites/default/files/national_sinap_combined_report_quarters_1-7_april_2011_-_december_

2012_0.pdf• 8. Royal College of Physicians. Sentinel Stroke National Audit Programme (SSNAP) Acute organizational audit report. 2014• https://www.strokeaudit.org/Documents/Results/National/2014/2014-AcuteOrgPublicReport.aspx• 9. Society and College of Radiographers How to implement best practice in stroke and TIA imaging. Synergy News Nov 2011:

15-17• 10. Mann G, Hankey GJ, Cameron D. Swallowing function after stroke: prognosis and prognostic factors after 6

months. Stroke. 1999, April 30 (4): 744-748.