Incidental findings in magnetic resonance imaging of the brains of healthy young men

Background and purpose: To determine the frequency of serious intracranial abnormalities in a healthy young male population. Methods: Cranial MRI of 2 536 healthy young males, mean age 20.5 years, all applicants for military flying duties in the German Air Force. Results: The authors report a variety of morphological abnormalities in the brains of a large population of healthy young males, providing data on disease prevalence. Arachnoid cysts were found in 1.7% (95% CI 1.2 to 2.3%), vascular abnormalities in 0.51% (95% CI 0.29 to 0.9%), and intracranial tumors in 0.47% (95% CI 0.26 to 0.85%) of the applicants. No cerebral aneurysms were found. Conclusion: The prevalence of primary brain tumors seems to be higher, whereas the prevalence of intracranial aneurysms is lower than expected. Only a small percentage of the detected abnormalities require urgent medical attention. (c) 2005 Elsevier B.V. All rights reserved.