Computed Tomography (CT) and Magnetic Resonance Imaging (MRI).
This report explores 13 conditions for which the use of CT and MRI remain controversial: arteriovenous malformations carotid artery disease, cerebral aneurysms, coronary artery disease, headaches, head injuries, lung cancer screening, peripheral vascular disease, pulmonary embolism, renal artery stenosis, seizures, stroke and urolithiasis screening.
Although CT and MRI are accepted investigations for some clinical conditions, uncertainty exists as to their value for other investigations.
Methods and Results
Published literature from January 2000 to November 2004 was identified and retrieved using a defined search strategy. A total of 48 articles were included in a systematic review (SR), reporting on 49 SRs that examined CT and MRI for the investigation of 11 of the 13 specified clinical conditions. Based on studies of the diagnostic accuracy of CT and MRI as compared with traditional gold standard investigations, promising evidence was found for applications for carotid artery disease, peripheral vascular disease, pulmonary embolism, renal artery stenosis and stroke. Findings were more cautious for cerebral aneurysms, coronary artery disease and lung cancer screening, while SR evidence was sparse for use of these technologies for the investigation of headaches, head injuries and seizures. No SR evidence was found for cerebral arteriovenous malformations or urolithiasis screening.
Implications for Decision Making
CT and MRI technologies may not be appropriate for every clinical condition. Evidence of effectiveness from recent systematic reviews (SRs) indicates that CT and MRI technologies can improve diagnostic certainty in some medical conditions. In other conditions, there was less compelling evidence or no evidence available. There was no evidence that CT and MRI technology has an effect on patients’ health or management.
Decisions regarding the use of CT and MRI should be based on an updated review and revisited. CT and MRI technology has advanced rapidly. Findings from the identified SRs may not be sufficiently contemporary to be useful for clinicians and decision makers.
To ensure the most effective use of CT and MRI, their influence on patient management and outcomes must be measured. By moving beyond the diagnostic accuracy of these technologies, more relevant assessments of the benefits and harms of such technologies will be possible.