Magnetization transfer effects in MR-detected multiple sclerosis lesions: comparison with gadolinium-enhanced spin-echo images and nonenhanced T1-weighted images

• Published in: American journal of neuroradiology : AJNR 1995-01, Vol.16 (1), p.69-77
• Main Authors: Hiehle, JF, Jr, Grossman, RI, Ramer, KN, Gonzalez-Scarano, F, Cohen, JA
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Biological and medical sciences; Blood-Brain Barrier; Brain - pathology; Cohort Studies; Comparative Study; Contrast Media - pharmacokinetics; Demyelinating Diseases - pathology; Gadolinium - pharmacokinetics; Humans; Image Enhancement - methods; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging - methods; Magnetics; Medical sciences; Middle Aged; Multiple Sclerosis - diagnosis; Multiple Sclerosis - pathology; Myelin Sheath - pathology; Nervous system; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Research Support, U.S. Gov't, P.H.S
• ISSN: 0195-6108; 1936-959X

To define the relationship between magnetization transfer and blood-brain-barrier breakdown in multiple sclerosis lesions using gadolinium enhancement as an index of the latter. Two hundred twenty lesions (high-signal abnormalities on T2-weighted images) in 35 multiple sclerosis patients were studied with gadolinium-enhanced spin-echo imaging and magnetization transfer. Lesions were divided into groups having nodular or uniform enhancement, ring enhancement, or no enhancement after gadolinium administration. For 133 lesions, T1-weighted images without contrast enhancement were also analyzed. These lesions were categorized as isointense or hypointense based on their appearance on the unenhanced T1-weighted images. There was no difference between the magnetization transfer ratio (MTR) of lesions as a function of enhancement. MTR of hypointense lesions on unenhanced T1-weighted images was, however, lower than the MTR of isointense lesions. We speculate that diminished MTR may reflect diminished myelin content and that hypointensity on T1-weighted images corresponds to demyelination. Central regions of ring-enhancing lesions had a lower MTR than the periphery, suggesting that demyelination in multiple sclerosis lesions occurs centrifugally. In addition, the short-repetition-time pulse sequence seems useful in the evaluation of myelin loss in patients with multiple sclerosis.