Brain Magnetic Resonance Imaging in Asthmatics

Abstract

RATIONALE: There are no published data on magnetic resonance imaging (MRI) of the brain in asthmatics. We report brain MRI findings performed as part of a pre-specified safety evaluation in subjects aged 19 to 47 years from 2 clinical trials involving mild to moderate asthmatics. METHODS: A neuroradiologist performed a blinded review of brain MRI scans performed at baseline and repeated after 4 weeks in both studies. The combined data were compared with literature reports for cohorts of similar age, with other diseases. RESULTS: Fourteen brain MRI abnormalities were noted in 13 of 21 (62%) subjects. Non-specific deep white matter hyperintensities (24%), perivascular space (20%), and abnormal anatomic findings (14%) were noted either at baseline or follow-up. Thirty-eight percent of subjects had a normal study. A recent report found that nonspecific white matter hyperintensities were also seen in 34% of healthy subjects aged 44-48 years. A comparison between normal controls and neuropsychiatric patients reported rates of 31% and 43% in patients and normal controls respectively, for subjects aged 18-50 years. These results suggest that incidental brain MRI findings are relatively common in healthy individuals and in patients with various diseases. CONCLUSIONS: The high rate of incidental brain MRI findings observed in our study and our literature review suggests that brain MRI may not be an appropriate screening tool to evaluate potential neurologic toxicity in asymptomatic study subjects during clinical trials. If brain MRI is employed, baseline studies are required.