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Proton Magnetic Resonance Spectroscopy and Gadolinium‐DTPA Perfusion Imaging of Asymptomatic MRI White Matter Lesions

1995; Wiley; Volume: 33; Issue: 1 Linguagem: Inglês

10.1002/mrm.1910330109

1522-2594

Stephen M. Oppenheimer, R. Nick Bryan, Thomas E. Conturo, Brian J. Soher, Thomas J. Preziosi, Peter B. Barker,

Advanced Neuroimaging Techniques and Applications

Abstract In the elderly, asymptomatic white matter hyperintensities are common on T 2 ‐weighted magnetic resonance imaging (MRI). In symptomatic patients, such MRI appearances correlate with varied postmortem findings including demyelination or stroke. What structural correlates underlie the T 2 hyperintensities in patients whose lesions are asymptomatic is controversial. Therefore, in order to investigate the underlying metabolism and perfusion in white matter lesions (exhibiting T 2 hyperintensity), 13 patients underwent proton magnetic resonance spectroscopy and dynamic gadolinium‐DTPA perfusion‐weighted MR imaging. N‐acetyl aspartate (NA) levels were reduced in the lesions compared with age‐matched controls (P = 0.031), implying neuronal/axonal loss. Creatine levels were also reduced (P = 0.001). Choline levels were unchanged in the lesions. Lactate was identified in the lesions of 5 of the 13 patients. Although not statistically significant, perfusion studies exhibited a trend toward lower cerebral blood volumes in patients with high grade extracranial carotid stenosis and lactate‐containing lesions. These findings suggest that neuronal/axonal loss underlies the majority of T 2 ‐weighted asymptomatic lesions in the older population, and in many cases these changes may be due to chronic ischemia.