Authors' objectives:

To present the options for diagnostic imaging after stroke, particularly in an emergency situation.

Authors' results and conclusions: Approach: The immediate aim after an acute stroke is to authenticate the stroke, establish the prognosis and, if appropriate and possible, prepare for thrombolysis. Available imaging methods: CT scan of the brain without injection, CT-angiography and perfusion CT, magnetic resonance imaging (MRI) (different sequences are used, particularly MR-angiography and diffusion MRI), and ultrasound methods (Doppler ultrasonography (TDUS) and transcranial Doppler). Examinations used in an emergency: Brain scan without injection of contrast medium and MRI are used in an emergency. - The best level of evidence supports the CT scan method. However, the early signs of cerebral ischaemia on CT scan are not always present and are difficult to interpret. CT scanning can help determine prognosis (risk of poor outcome, risk of severe haemorrhagic transformation and functional prognosis at 3 months). - Controlled trials tend to show that MRI is more sensitive (and has a higher level of agreement between observers) in assessing lesions and their extent, and is better than CT scan for distinguishing acute lesions from secondary lesions. Visualising the main arteries. The choice is between MR-angiography (MRI sequence) and transcranial Doppler ultrasonography (TDUS), and will depend on the imaging method used initially for the parenchyma. Cervical imaging. This is performed when the question of thrombolysis has been resolved. It may include TDUS, MR-angiography, CT-angiography, or even conventional arteriography before surgery. In practice, a combination of TDUS and MR-angiography currently appears to be best for exploring the extracranial arteries, occasionally completed by CT-angiography for more precise information, for example about degree of stenosis.

Authors' recommendations: Objective measurement of the patient's haemodynamic status and characterisation of the penumbra means that management could be tailored more closely to the individual. More clinical trials of revascularisation therapy are needed to define imaging criteria that can be used to select patients who could be treated with thrombolysis after three hours. The method which has been most studied for this purpose is a combination of diffusion/perfusion MRI and MR-angiography. However, CT-angiography would seem to be a possible alternative, while the role of multislice scanners has not yet been evaluated.

Authors' methods: Review

Project Status: Completed

URL for project: http://www.has-sante.fr/

Year Published: 2002

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: France

Organisation Name: L'Agence Nationale d'Accreditation d'Evaluation en Santé

Contact Address: 2 avenue du Stade de France, 93218 Saint-Denis La Plaine Cedex, France. Tel: +33 01 55 93 71 88; Fax: +33 01 55 93 74 35;

Contact Name: sh.leerobin@has-sante.fr

Contact Email: sh.leerobin@has-sante.fr

Copyright: L'Agence Nationale d'Accreditation d'Evaluation en Sante (ANAES)