MR multispectral analysis of multiple sclerosis lesions

J. Ross Mitchell, Craig Jones, Stephen J. Karlik, Karen Kennedy, Donald H. Lee, Brian Rutt, Aaron Fenster

Research output: Contribution to journalArticle

Abstract

Although quantification of the lesion burden from serial MR examinations of patients with multiple sclerosis (MS) is a common technique to assess disease activity in clinical trials, pathologic change may occur within a lesion without a corresponding change in volume. Therefore, measures of lesion volume and composition may improve the sensitivity of detecting disease activity. A new technique has been developed that provides information about the intensity composition of MS lesions in standard spin- echo MR examinations. The new technique is based on the multispectral 'feature space' intensity distributions of the lesions and normal tissues. Analysis of MR examinations of materials with known T1 and T2 times showed that feature space position from spin-echo examinations is largely determined from proton density (ρ), T2, and the interecho delay. Information about intensity composition was obtained by reducing the multidimensional intensity distribution to one dimension while minimizing the loss of information. This technique was used to analyze eight lesions in standard spin-echo MR examinations of three patients with MS. Lesion distributions were compared between examinations by first calibrating the examinations based on the intensity distributions of cerebrospinal fluid (CSF), an internal reference tissue. Many of the lesion distributions had a distinctive peak at low intensity, corresponding to normal-appearing white matter (WM). Within the lesion distributions, increases in high intensity peaks generally were accompanied by reductions in the WM peak. Serial analysis of the lesion distributions revealed some dramatic fluctuations, even when lesion volume remained constant.

Original languageEnglish (US)
Pages (from-to)499-511
Number of pages13
JournalJournal of Magnetic Resonance Imaging
Volume7
Issue number3
DOIs
Publication statusPublished - 1997
Externally publishedYes

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Keywords

  • Cluster classification
  • MR
  • Multiple sclerosis
  • Multispectral analysis
  • Principal components
  • Quantification

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Cite this

Mitchell, J. R., Jones, C., Karlik, S. J., Kennedy, K., Lee, D. H., Rutt, B., & Fenster, A. (1997). MR multispectral analysis of multiple sclerosis lesions. Journal of Magnetic Resonance Imaging, 7(3), 499-511. https://doi.org/10.1002/jmri.1880070309