Significance of Brain MRI Incidental Findings in Older Patients

Most incidental findings detected during brain MR imaging in the middle-aged and elderly population do not have direct clinical consequences, according to a study published in Radiology.

Researchers from the Netherlands performed a prospective study to determine updated prevalence estimate for incidental findings on brain MR images and provide information on clinical relevance, including natural course, over a period of up to nine years.

The researchers enrolled 5,800 study subjects, mean age 64.9; 3,194 subjects (55.1%) were women. All underwent structural brain MR imaging. Trained reviewers recorded abnormalities, which were subsequently evaluated by neuroradiologists. The prevalence with 95% confidence interval (CI) of incidental findings was determined, and clinical management of findings that required the attention of a medical specialist was followed. Follow-up imaging in the study context provided information on the natural course of findings that were not referred.

The results showed that 549 of the participants (9.5%) had incidental findings. The most common were meningiomas (143 subjects) and cerebral aneurysms (134). A total of 188 patients were referred to medical specialists based on the incidental findings. One-hundred-forty-four of these patients (76.6%) either underwent a wait-and-see policy or were discharged after the initial clinical visit. The majority of meningiomas and virtually all aneurysms not referred or referred but untreated remained stable in size during follow-up.

The researchers concluded that incidental findings at brain MR imaging that necessitate further diagnostic evaluation occur in over 3% of the general middle-aged and elderly population, but are mostly without direct clinical consequences.