Abstract

INTRODUCTION

A CT scan of the brain is an indispensable component of the clinical assessment of patients with acute stroke. It rapidly demonstrates stroke-mimicking conditions, and – within the first week of stroke – is still the best way to differentiate haemorrhage from infarct. However, the old view that the CT was essentially normal in ischaemic stroke is no longer valid. Subtle, early signs of infarction have been identified, which help to confirm the diagnosis and may guide treatment. In this review, we will discuss some of the factors that influence the appearance of the CT scan in acute stroke. We will describe the early signs of infarction, what they mean, and areas of uncertainty that require more study. We will highlight some of the limitations of CT scanning, suggest clinical situations where MR may be appropriate, and what sequences should be requested.

In 2001, and for the foreseeable future, CT is