Pocket Sized Carotid Stenosis Screening by Junior Doctors

Screening Patients Admitted With Stroke or TIA for Carotid Stenosis by Pocked-Sized Ultrasound in Inexperienced Hands and With Novel Doppler Technology

Among patients admitted with cerebral ischemia (stroke and transitory ischemic attack (TIA)) it is important to reveal the underlying cause of the disease. In special it is important to reveal if carotid artery stenosis is present as such a finding will directly influence on treatment and follow-up. For the diagnosis of carotid artery stenosis due to atherosclerosis ultrasound examinations is the cornerstone, but computer tomography and magnetic resonance imaging may be better in some cases. Development of high quality pocket-sized ultrasound scanners has allowed for semi quantitatively bed-side assessment of the carotid arteries and the heart. The investigators aim to study the feasibility and reliability of bed-side assessment of the carotid arteries by pocket-sized ultrasound scanners in inexperienced hands and the clinical influence of this examination when performed by experienced users. The investigators hypothesize that a significant proportion of this patient population can be clarified bed-side by junior doctors with no need of further imaging procedures for the assessment of the carotid arteries and the heart.

Population: Approximately 100 patients admitted to the Department of Medicine, Levanger Hospital and Stroke Department, St. Olavs Hospital with history and findings suspicious of stroke/transitory ischemic attack (TIA). Informed consent mandatory. Exclusion criteria: CT angiography of carotid vessels performed after index event, unless all participating clinicians are fully blinded to the results. Hypotheses: The carotid arteries can be assessed bed-side by pocket-size ultrasound scanners with high feasibility and reliability by junior doctors with limited training. Bed-side assessment of the carotid arteries by pocket-size ultrasound scanners may reduce the need for more advanced (higher cost) imaging procedures. New high frame rate tracking doppler can increase accuracy and reproducability of stenosis grading. Methods: Pocket-size imaging device from GE Ultrasound, commercial available. Approved for clinical use. High-end carotid Doppler ultrasound by high-end equipment (GE Vivid 9) and computer tomography and magnetic resonance imaging at the Department of Radiology, Levanger Hospital and St. Olavs Hospital Verasonics research scanner for high fram rate imaging

Ischemic Attack, Transient, Transient Ischemic Attack, Stroke, Cerebrovascular Accident, Cerebrovascular Apoplexy

All participants will be examined bed-side by pocket size ultrasound for the assessment of the carotid arteries by junior doctors. All participants will then be examined by reference imaging in specific ultrasound laboratories with conventional high end equipment and new doppler techniques and when appropriate computer tomography or magnetic resonance imaging.

Proportion of patients which is not in need of further imaging procedures of the carotid arteries after bed-side diagnostic ultrasound performed by junior doctors with with pocket-sized scanner

The participants will be followed for the duration of hospital stay, an expected average of approximately 4 days

Reliability of bed-side ultrasound examinations of the carotid arteries performed by junior doctors with pocket-sized scanners

The accuracy of semi quantitatively classifications (like i.e. non-significant atherosclerosis of the carotid arteries vs significant stenosis of the carotid arteries) of bed-side ultrasound examinations of the carotid arteries performed by junior doctors with pocket-sized scanners compared with reference methods performed by experienced personnel

The participants will be followed for the duration of hospital stay, an expected average of approximately 4 days

Proportion of interpretable examinations with bed-side ultrasound examinations of the carotid arteries performed by junior doctors with pocket-sized scanners

Proportion of bed-side ultrasound examinations of the carotid arteries performed by junior doctors with pocket-sized scanners of sufficient quality compared with reference imaging methods. Quality includes both to what extent the specific structure can be completely assessed, and to what degree the recordings can be interpreted by the operator. Structures and specific functions to be tested: carotid arteries with respect to degree of atherosclerosis and stenosis

The participants will be followed for the duration of hospital stay, an expected average of approximately 4 days

Total time used to record the ultrasound images of the carotid arteries by the junior doctors with pocket-sized ultrasound equipment.

The participants will be followed for the duration of hospital stay, an expected average of approximately 4 days

Accuracy of high frame rate tracking doppler compared to conventional doppler measurements and computed tomography for grading carotid stenosis.

Accuracy of velocity measurements with high frame rate tracking doppler for judging degree of stenosis compared to conventional pulsed wave doppler and computed tomography angiography

The participants will be followed for the duration of hospital stay, an expected average of approximately 4 days

Clinical influence of bed-side ultrasound examinations of the carotid arteries in patients admitted with symptoms of stroke

In addition to what described in the primary measure it will be of interest to study predictors of clinical influence of different patient characteristics as age, sex, history, anatomic localization of the vascular event, medication, heart rhythms, ECG findings). Furthermore, the influence on the total cost will be studied.

The participants will be followed for the duration of hospital stay, an expected average of approximately 4 days

Inclusion Criteria: Admitted to the Department of Medicine with history and findings suspicious of (transient) cerebrovascular ischemia and willing and able to give their informed written consent Exclusion Criteria: Evaluation of carotid artery stenosis by imaging (CT, MRI or ultrasound) performed during the stay prior to inclusion.

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