Abstract

Background
Chronic headache is one of the most common symptoms in neurological outpatient clinic. It had low likelihood for discovering significant disease to evaluate chronic headache patients with normal neurological examinations by magnetic resonance imaging(MRI) because previous studies considered silent brain infarct(SBI) as not significant lesion. We investigated the incidence of abnormal findings including SBI in MRI of the brain for the patients who have normal neurological examinations. Methods: We retrospectively reviewed the medical records and MR images of 455 patients with chronic headache between January 2001 and December 2002. Only 212 patients with normal neurological examinations were included in this study. Results: The patients were diagnosed as having tension type headache(76.9%), migraine(25.6%), and atypical type headache(6.1%). Clinical significant abnormalities on MRI were found in 29 patients(13.7 %) which were silent infarct, tumor, AVM and aneurysm. The most common abnormalities on MRI was SBI(n=19, 66.5%). We found that SBI on MRI was related to heart disease, hypertension, and types of chronic headache. Conclusion: These results indicate that patients with chronic headache have higher risk of SBI which may be independent risk factor for symptomatic brain infarcts. Korean Journal of Headache 6(1):89-94, 2005