Elsevier

NeuroImage

Volume 47, Issue 4, 1 October 2009, Pages 1352-1362
NeuroImage

Signal abnormalities on 1.5 and 3 Tesla brain MRI in multiple sclerosis patients and healthy controls. A morphological and spatial quantitative comparison study

https://doi.org/10.1016/j.neuroimage.2009.04.019Get rights and content

Abstract

Previous studies in patients with multiple sclerosis (MS) revealed increased lesion count and volume on 3 T compared to 1.5 T. Morphological and spatial lesion characteristics between 1.5 T and 3 T have not been examined. The aim of this study was to investigate the effect of changing from a 1.5 T to a 3 T MRI scanner on the number, volume and spatial distribution of signal abnormalities (SA) on brain MRI in a sample of MS patients and normal controls (NC), using pair- and voxel-wise comparison procedures. Forty-one (41) MS patients (32 relapsing-remitting and 9 secondary-progressive) and 38 NC were examined on both 1.5 T and 3 T within one week in random order. T2-weighted hyperintensities (T2H) and T1-weighted hypointensities (T1H) were outlined semiautomatically by two operators in a blinded fashion on 1.5 T and 3 T images. Spatial lesion distribution was assessed using T2 and T1 voxel-wise SA probability maps (SAPM). Pair-wise analysis examined the proportion of SA not simultaneously outlined on 1.5 T and 3 T. A posteriori unblinded analysis was conducted to examine the non-overlapping identifications of SA between the 1.5 T and 3 T. For pair-wise T2- and T1-analyses, a higher number and individual volume of SA were detected on 3 T compared to 1.5 T (p < 0.0001) in both MS and NC. Logistic regression analysis showed that the likelihood of missing SA on 1.5 T was significantly higher for smaller SA in both MS and NC groups. SA probability map (SAPM) analysis revealed significantly more regionally distinct spatial SA differences on 3 T compared to 1.5 T in both groups (p < 0.05); these were most pronounced in the occipital, periventricular and cortical regions for T2H. This study provides important information regarding morphological and spatial differences between data acquired using 1.5 T and 3 T protocols at the two scanner field strengths.

Introduction

Magnetic resonance imaging (MRI) has a unique sensitivity for detecting tissue abnormalities in the central nervous system (CNS). Therefore, its use has been progressively increased in recent decades, enabling better diagnosis and prognosis of several neurological diseases.

In particular, MRI is the most sensitive diagnostic method for detection of inflammatory lesions in the CNS in patients with multiple sclerosis (MS) (Zivadinov, 2007). MRI plays an important role in diagnosis and prognosis of MS (McDonald et al., 2001) and is also commonly used as a surrogate marker to monitor disease activity in clinical trials (Miller, 1995, Paty et al., 1994).

The MRI criteria for MS focus on evidence for dissemination of lesions in time and space (McDonald et al., 2001), but several factors can affect the number and volume of MS lesions that can be identified on serial MRI scans. These include: the choice of pulse sequence (Filippi et al., 1996, Patola et al., 2001, Yousry et al., 1997), slice thickness (Dolezal et al., 2007, Filippi et al., 1998b, Molyneux et al., 1998), repositioning errors (Filippi et al., 1997), spatial resolution (Molyneux et al., 1998), differences among types of scanners (Filippi et al., 1999) and magnetic field strengths (Schima et al., 1993, Sicotte et al., 2003).

As high-field imaging becomes increasingly available in clinical routine care, it is more important than ever to understand the impact on SA detection rate of a change to higher field, including commonly associated changes in sequence parameters and/or resolution.

Higher field strength has been shown to detect more SA in clinically defined MS (Fischbach and Bruhn, 2008, Keiper et al., 1998, Lee et al., 1995, Sicotte et al., 2003) and in clinically isolated syndrome (Wattjes et al., 2006a, 2008).

Recent studies have used voxel-wise techniques to compare lesion distributions across populations (Charil et al., 2003, DeCarli et al., 2005, Di Perri et al., 2008, Enzinger et al., 2006, Ghassemi et al., 2008, Lee et al., 1998, Narayanan et al., 1997, Wen and Sachdev, 2004), and the resulting statistical parametric and non-parametric SA probability maps (SAPM) have been shown to be powerful tools for studying SA distribution in vivo.

To the best of our knowledge, SA characteristics between clinically common 1.5 T and 3 T imaging protocols have never been evaluated using fully automated and technically advanced comparison procedures. In particular, no MR studies have focused on possible morphological and spatial differences in brain SA distribution between the two different imaging protocols in MS patients and normal controls (NC).

On this basis, we aimed to investigate the effect of changing to a higher-field scanner on the number, volume and spatial distribution of SA on brain MRI in a sample of MS patients and NC, using SA paired- and voxel-wise fully automated comparison procedures.

Section snippets

Study population

We studied 41 MS patients and 38 NC. All patients were consecutively selected from patients referred to the MS outpatient clinic who fulfilled the criteria for definite MS (Polman et al., 2005). The inclusion criteria were: MRI examination performed at the time of their clinical visit (+/− 24 h), age 18–80 years, Expanded Disability Status Scale (EDSS) (Kurtzke, 1983) 0–8.5, and relapsing-remitting (RR) or secondary-progressive (SP) disease type (Lublin and Reingold, 1996). Exclusion criteria

Demographic characteristics

The study included 41 MS patients (sex: 32 females; disease course: 32 RR, 9 SP; age in years: mean 45.5 ± 8.7, median 47, range 22–58; age at onset in years: mean 30.8 ± 8.3, median 30.5, range 18–50; age at diagnosis in years: mean 34.7 ± 9.2, median 35, range 19–50; disease duration in years: mean 14.9 ± 7.9, median 14.9, range 2–40; EDSS: mean 3.5 ± 2, median 3.7, range 0–7) and 38 NC (sex: 26 females; age in years: mean 37.76 ± 12.9, median 35.5, range 19–60). DMT status was distributed as follows: 27

Discussion

In the present study, we assessed morphological and spatial SA differences between scans acquired on 1.5 T and 3 T scanners using fully automated pair- and voxel-wise quantitative comparison methods.

For pair-wise per SA number and individual volume analyses in MS patients, 3 T showed 16.9% more T2H by number and 35.7% higher T2H volume compared to 1.5 T, and for T1 lesion-wise paired analysis, 3 T showed 25% more T1H by number and 20% higher T1H volume compared to 1.5 T (Table 3, Table 4). In

Conclusions

This lesion- and voxel-wise comparison study between 1.5 T and 3 T scanners in MS patients and NC provides important information regarding morphological and spatial differences between the two scanning approaches.

Use of high-field MRI systems (3 T) increases the likelihood of detecting T2H and T1H, especially those of smaller individual volume. The spatial differences are not homogeneous, i.e., it is more likely to detect more SA in specific brain areas. Further studies are warranted to

Acknowledgments

This study was performed as part of a research collaboration agreement among General Electric Company, The State University of New York at Buffalo, Kaleida Health Systems, and University Neurology, Inc. Dr. Robert Zivadinov served as PI on this research. The authors have no financial relationship to disclose.

Dr. Carol Di Perri was supported by the Dr. Larry D. Jacobs Jog-for-the-Jake Fellowship. We also thank Eve Salczynski for technical support in the preparation of this manuscript.

References (51)

  • DeCarliC. et al.

    Anatomical mapping of white matter hyperintensities (WMH): exploring the relationships between periventricular WMH, deep WMH, and total WMH burden

    Stroke

    (2005)
  • Di PerriC. et al.

    Voxel-based assessment of differences in damage and distribution of white matter lesions between patients with primary progressive and relapsing-remitting multiple sclerosis

    Arch. Neurol.

    (2008)
  • EnzingerC. et al.

    Lesion probability maps of white matter hyperintensities in elderly individuals: results of the Austrian stroke prevention study

    J. Neurol.

    (2006)
  • FazekasF. et al.

    Pathologic correlates of incidental MRI white matter signal hyperintensities

    Neurology

    (1993)
  • FilippiM. et al.

    Quantitative assessment of MRI lesion load in multiple sclerosis. A comparison of conventional spin-echo with fast fluid-attenuated inversion recovery

    Brain

    (1996)
  • FilippiM. et al.

    The effect of imprecise repositioning on lesion volume measurements in patients with multiple sclerosis

    Neurology

    (1997)
  • FilippiM. et al.

    Interscanner variation in brain MR lesion load measurements in multiple sclerosis using conventional spin-echo, rapid relaxation-enhanced, and fast-FLAIR sequences

    AJNR Am. J. Neuroradiol.

    (1999)
  • FilippiM. et al.

    Effect of training and different measurement strategies on the reproducibility of brain MRI lesion load measurements in multiple sclerosis

    Neurology

    (1998)
  • FilippiM. et al.

    Intraobserver and interobserver variability in measuring changes in lesion volume on serial brain MR images in multiple sclerosis

    AJNR Am. J. Neuroradiol.

    (1998)
  • FischbachF. et al.

    Assessment of in vivo 1H magnetic resonance spectroscopy in the liver: a review

    Liver Int.

    (2008)
  • GhassemiR. et al.

    Lesion distribution in children with clinically isolated syndromes

    Ann. Neurol.

    (2008)
  • Gunning-DixonF.M. et al.

    The cognitive correlates of white matter abnormalities in normal aging: a quantitative review

    Neuropsychology

    (2000)
  • HopkinsR.O. et al.

    Prevalence of white matter hyperintensities in a young healthy population

    J. Neuroimaging

    (2006)
  • KeiperM.D. et al.

    MR identification of white matter abnormalities in multiple sclerosis: a comparison between 1.5 T and 4 T

    AJNR Am. J. Neuroradiol.

    (1998)
  • KurtzkeJ.F.

    Rating neurologic impairment in multiple sclerosis: an expanded disability status scale (EDSS)

    Neurology

    (1983)
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