From the Guidelines
For a brain MRI to evaluate worsening mental status, a non-contrast MRI is usually sufficient and should be the initial choice. This approach is supported by the most recent evidence from the American College of Radiology, which suggests that MRI without IV contrast may prove useful in the setting of altered mental status as a second-line test when occult pathology is suspected and initial head CTs are unrevealing 1. The use of non-contrast MRI is particularly valuable for detecting ischemia, encephalitis, or subtle cases of subarachnoid hemorrhage, and it may also be considered as a first-line test in certain situations, such as a clinically stable patient with known malignancy, HIV, or endocarditis 1. However, in cases where intracranial infection, tumor, inflammatory lesions, or vascular pathologies are suspected, MRI examinations without and with IV contrast may be performed 1. Key points to consider when deciding on the use of contrast include:
- The patient's clinical stability and history of malignancy, HIV, or endocarditis
- The presence of focal neurological deficits or recent falls
- The suspicion of intracranial infection, tumor, or vascular pathologies
- The need for definitive characterization of a focal lesion identified on initial noncontrast CT. In general, the decision to use contrast should be made on a case-by-case basis, taking into account the individual patient's clinical presentation and the potential benefits and risks of contrast administration 1.
From the Research
Brain MRI for Worsening Mental Status
- The provided studies do not directly address the use of contrast in brain MRI for worsening mental status.
- However, they discuss the use of gadolinium-based contrast agents in MRI and their potential nephrotoxicity, particularly in patients with renal disease 2, 3, 4, 5, 6.
- There is no specific guidance on the use of contrast in brain MRI for worsening mental status, as the studies focus on renal function and the risks associated with gadolinium-based contrast agents.
- The decision to use contrast or not would depend on the individual patient's condition and the specific clinical question being addressed, but this information is not provided in the available studies.