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Table 3: Advantages and limitations of CT and MR imaging
Imaging Characteristics CT MRI
Availability in the acute setting (0–6 hours) ++ −
Rapid image acquisition ++ +
Lack of vulnerability to motion artifacts + −
Accessibility for patients with monitors and/or ventilators ++ −
Feasibility and safety for patients with metallic implants (pacemakers, implantable defibrillators) ++ −
Lower cost + −
Lack of ionizing radiation − ++
Renal toxicity associated with contrast administration + +
Time for postprocessing angiography and perfusion imaging − −
Sensitivity to lacunar and posterior fossa infarcts − ++
Differentiation between acute and chronic ischemia − ++
Ability to assess causes of ICH or SAH while in the scanner + +
Detection of chronic hemorrhage including microbleeds − +
Note:—ICH indicates intracranial hemorrhage.