Is magnetic resonance imaging (MRI) indicated for a patient presenting with new onset memory loss and headaches?

From the Guidelines

Magnetic resonance imaging (MRI) is indicated for a patient presenting with new onset memory loss and headaches, as it is recommended over computed tomography (CT) for its higher sensitivity to vascular lesions and certain subtypes of dementia. This recommendation is based on the 5th Canadian Consensus Conference on the Diagnosis and Treatment of Dementia, published in 2020 1. The guidelines suggest that anatomical neuroimaging, such as MRI, is recommended in most situations, including the onset of cognitive signs/symptoms within the past 2 years, unexpected and unexplained decline in cognition and/or functional status, and unexplained neurological manifestations like new onset severe headache.

The preferred MRI sequences for evaluating patients with new onset memory loss and headaches include:

• 3D T1 volumetric sequence (including coronal reformations for hippocampal volume assessment)
• Fluid-attenuated inversion recovery (FLAIR)
• T2 (or susceptibility-weighted imaging [SWI] if available)
• Diffusion-weighted imaging (DWI)

These sequences can help identify potential structural causes of the patient's symptoms, such as vascular lesions, tumors, or other intracranial abnormalities. The use of semi-quantitative scales, such as the medial temporal lobe atrophy (MTA) scale, Fazekas scale, and global cortical atrophy (GCA), is also recommended for routine interpretation of MRI scans 1.

While awaiting the MRI results, a thorough neurological examination and cognitive assessment should be performed to better characterize the memory deficits. The patient should also be asked about the pattern of headaches, including onset, duration, severity, and associated symptoms, to help narrow the differential diagnosis. Depending on the clinical suspicion, additional workup might include laboratory tests to rule out metabolic, infectious, or inflammatory causes of cognitive changes.

From the Research

Indications for MRI in New-Onset Memory Loss and Headaches

• The decision to use magnetic resonance imaging (MRI) for a patient presenting with new onset memory loss and headaches depends on various factors, including the presence of other symptoms and the results of a careful history and physical examination 2, 3, 4, 5.
• According to the study published in 1996, the yield of neuroimaging in the evaluation of patients with headache and a normal neurologic examination is quite low, with brain tumors, arteriovenous malformations, hydrocephalus, aneurysm, subdural hematoma, and strokes being detected in less than 3% of cases 2.
• However, the same study suggests that MRI may be indicated in certain cases, such as when there is a high index of suspicion for a secondary headache disorder, or when the patient presents with a "first or worst" headache, which may be indicative of an acute subarachnoid hemorrhage 2.
• The 2021 study published in The Medical clinics of North America recommends that imaging is generally not warranted for headaches, but may be necessary in certain cases, such as when there are red flags or abnormal findings on physical examination 3.
• Another 2021 study published in Praxis suggests that brain imaging, including MRI, may be necessary for the assessment of new-onset headaches in adults, especially when there is suspicion of a secondary headache disorder 4, 5.
• The 2016 study published in JAMA recommends the use of epilepsy protocol-specific magnetic resonance imaging of the brain, which includes thin-cut coronal slices, for patients diagnosed with first-time unprovoked seizure, but does not specifically address the use of MRI for new-onset memory loss and headaches 6.

Considerations for MRI Use

• The use of MRI should be guided by a careful history and physical examination, and should be considered on a case-by-case basis 2, 3, 4, 5.
• The presence of red flags, such as sudden onset of headache, worsening of headache over time, or abnormal findings on physical examination, may indicate the need for MRI 3, 4, 5.
• The patient's age, medical history, and other factors should also be taken into consideration when deciding whether to use MRI 2, 3, 4, 5.