MRA results are accurate, fast in stroke patients

Time-resolved MR angiography (MRA) has proven itself a valuable tool in the quick assessment of vascular disease in stroke patients, according to a study published online Jan. 15 in Academic Radiology.

While non-contrast brain CT is a first-line imaging solution in stroke patients because of its speed and availability, some physicians are turning to MRI for patients with unknown symptom onset, such as wake-up stroke (WUS) patients, said study authors Achim Seeger, MD, with the Department of Diagnostic and Interventional Neuroradiology at Eberhard-Karls-University in Germany, and colleagues.

“The aim of this study was to evaluate the diagnostic performance of time-resolved MRA both for the assessment of pathologies in the extracranial and intracranial vessels and for the feasibility and reliability of perfusion information calculated from time-resolved MRA source data. Based on this information, the feasibility of an ultrafast MR stroke protocol should be assessed,” Seeger and colleagues wrote.

For the study, 19 patients with WUS were included and image quality and vessel pathologies were evaluated. The images were correlated to time-of-flight MRA, CT angiography, sonography and conventional angiography.

“The decision to perform MRI and time-resolved MRA was made individually by an interdisciplinary team consisting of at least one neurologist and an interventional neuroradiologist to allow intravenous thrombolysis therapy or local thrombectomy/thrombolysis as fast as possible,” the authors wrote.

The researchers found that time-resolved MRA enables rapid monitoring of the cerebrovascular system and its advantages over other imaging modalities for WUS patients includes the lack of time-consuming planning and delay—making it the fastest currently available MR sequence technique for assessing extracranial carotid arteries and intracranial arteries.

“In addition to diagnosis of high-grade stenosis or vessel occlusion also in the cervical parts of VA and ICA, time-resolved MRA offers the unique opportunity to obtain information about cerebral perfusion simultaneously for a comprehensive assessment of cerebral infarctions,” Seeger and colleagues wrote.

The authors concluded that for patients with WUS, time-resolved MRA is the fastest available sequence vessel analysis that is easy to apply.

“Time-resolved MRA provides reliable information about intracranial and extracranial vasculature. Cerebral perfusion estimation can be performed in selected cases for therapy decision but can be hampered by patient movement,” Seeger and colleagues wrote.  “However, DSC remains the standard technique for perfusion imaging until appropriate postprocessing software solutions are available.”