Limitations of the MRI Brain

• Limited ability in imaging the skull and facial bones -- conventional X-ray or CT scan is better in demonstrating bone details.
• Compared to CT scanning, MRI is less sensitive in demonstrating acute hemorrhage, as in subarachnoid hemorrhage and hemorrhagic infarction.
• Hard to depict calcifications
• MRI does not always distinguish tumor tissue from edema fluid
• Less sensitive in detecting small abnormalities compared to CT scans (poor spatial resolution)
• Inability to scan critically-ill patients requiring life support systems and monitoring devices that employ ferromagnetic materials.
• May be dangerous in scanning patients with metal implants and other metal objects
• May provoke claustrophobia
• Longer exam time compared to CT scans
• Safety in scanning pregnant women is not known.