Advanced

AJNR - American Journal of Neuroradiology

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Zhou, L. Q. Articles by Filippi, M. Search for Related Content PubMed PubMed Citation Articles by Zhou, L. Q. Articles by Filippi, M.

American Journal of Neuroradiology 25:1234-1241, August 2004
© 2004 American Society of Neuroradiology

BRAIN

A New Method for Analyzing Histograms of Brain Magnetization Transfer Ratios: Comparison with Existing Techniques

Liang Qiang Zhou^a, Yue Min Zhu^a, Jérôme Grimaud^a,c, Marc Hermier^a,b, Marco Rovaris^d and Massimo Filippi^d

^a CREATIS, CNRS UMR 5515 and INSERM 4630, Chartres, France
^b Hospital of Neurology of Lyon, Chartres, France
^c Hospital Louis Pasteur, Chartres, France
^d Neuroimaging Research Unit, Department of Neurology, Scientific Institute and University H San Raffaele, Milan, Italy

Address reprint requests to Y.M. Zhu, CREATIS, Bat. B. Pascal, INSA Lyon, 69621 Villeurbanne Cedex, France

BACKGROUND AND PURPOSE: Previously reported quantitative parameters for the magnetization transfer ratio (MTR) do not give identical results, which can limit their ability to differentiate normal from diseased tissue and render them vulnerable to variations among MR systems. Our purpose was to systematically study different MTR metrics; propose a new MTR histogram parameter, AMTR_2/3; and compare AMTR_2/3 with existing parameters in a study of multiple sclerosis (MS).

METHODS: Seven conventional MTR parameters were proposed: global and mean MTR; peak height and position of the histogram; and percentiles MTR₂₅, MTR₅₀, and MTR₇₅. Additionally, we investigated a parameter, AMTR_2/3, to indicate the normalized pixel count (area under the histogram curve) inside the band size of two-thirds MTR histogram peak height. All parameters were measured in 10 patients with relapsing-remitting MS (group A), 10 healthy control subjects from the same imaging center as that of patients (group B), and four healthy control subjects from an outside institution (group C). Comparison of findings was performed between groups A and B to assess the discriminating ability of MTR parameters and groups B and C to evaluate intersystem variations.

RESULTS: All MTR parameters differed between groups A and B, but the difference was significant for only global MTR, mean MTR, MTR₂₅, and AMTR_2/3. With the exception of AMTR_2/3, all parameters differed significantly between the two control groups.

CONCLUSION: AMTR_2/3 is less sensitive to MR imaging system variations than are other MTR parameters and was most effective in differentiating patients with MS from healthy control subjects. This finding supports the use of AMTR_2/3 in multicenter MT MR imaging studies of MS.

This article has been cited by other articles:

				Z. Khaleeli, D. R. Altmann, M. Cercignani, O. Ciccarelli, D. H. Miller, and A. J. Thompson Magnetization Transfer Ratio in Gray Matter: A Potential Surrogate Marker for Progression in Early Primary Progressive Multiple Sclerosis Arch Neurol, November 1, 2008; 65(11): 1454 - 1459. [Abstract] [Full Text] [PDF]

				M. Law, R. Young, J. Babb, E. Pollack, and G. Johnson Histogram Analysis versus Region of Interest Analysis of Dynamic Susceptibility Contrast Perfusion MR Imaging Data in the Grading of Cerebral Gliomas AJNR Am. J. Neuroradiol., April 1, 2007; 28(4): 761 - 766. [Abstract] [Full Text] [PDF]