Head CT > Stroke > CT scanning

CT scanning

There are several advantages to performing a CT scan instead of other imaging modalities. A CT scan:
- Is readily available
- Is rapid
- Allows easy exclusion of hemorrhage
- Allows the assessment of parenchymal damage

The disadvantages of CT include the following:
- Old versus new infarcts is not always clear
- No functional information (yet)
- Limited evaluation of vertebrobasilar system

A CT is 58% sensitive for infarction within the first 24 hours (Bryan et al, 1991). MRI is 82% sensitive. If the patient is imaged greater than 24 hours after the event, both CT and MR are greater than 90% sensitive.