Does perfusion imaging add value compared with plain parenchymal and vascular imaging?
- 1Department of Radiology, Neuroradiology Division, University of Virginia, Charlottesville, Virginia, USA
- 2Department of Neurology, Military General Hospital of Beijing PLA, Beijing, China
- 3Department of Neurology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- 4Department of Neurology, Centre Hospitalier Universitaire Vaudois, Switzerland
- Correspondence to Dr Max Wintermark, Associate Professor of Radiology, Neurology, Neurosurgery and Biomedical Engineering; Chief of Neuroradiology, UVA Department of Radiology, Neuroradiology Division, Box 800170, Charlottesville, VA 22908, USA;
Contributors All authors contributed.
- Accepted 9 May 2012
- CT perfusion
Stroke is a leading cause of mortality and disability worldwide, with 15 million people having a stroke annually. Given that it is very difficult to distinguish an ischemic from a hemorrhagic stroke on a clinical basis, neuroimaging—CT or MRI—plays a central role in the evaluation of patients with acute stroke symptoms. Because of significant advances over the last decade, imaging now provides information beyond the mere presence or absence of intracerebral hemorrhage. Comprehensive neurovascular imaging protocols using CT or MRI can be acquired within minutes, helping to distinguish stroke etiology and guide treatment decisions for acute reperfusion therapies. The role of imaging in guiding stroke treatment is such that the concept of ‘time is brain’ is slowly being replaced by that of ‘pathophysiology is brain’ or ‘imaging is brain’.1 Nevertheless, there are a number of uncertainties and controversies around the use of advanced imaging in acute stroke management. In particular, there is still insufficient proof that perfusion imaging-based treatment decisions improve clinical outcome in patients with acute ischemic stroke.
The goal of this article is to review commonly discussed issues about the role of perfusion imaging in acute stroke through a series of questions and to propose arguments to explain why perfusion imaging is useful and may improve diagnosis, triage, treatment decision and, ultimately, outcome of acute stroke.
Is perfusion imaging useful in acute ischemic stroke?
Yes, perfusion imaging adds unique information compared with plain parenchymal and vascular imaging.
Due to the wide availability, speed and patient tolerance, non-contrast head CT (NCCT) has traditionally been the first step for the evaluation of acute ischemic stroke. Although some early signs can be helpful in diagnosing an acute ischemic stroke, they are difficult to detect and their detection depends on the experience of the reader. Also, it provides solely structural—and not physiologic—information. NCCT can reliably …