A Magnetization Transfer Histogram Study Of Normal-Appearing Brain Tissue In MS
Tortorella C, Viti B, Bozzali M, Sormani MP, Rizzo G, Gilardi MF, Comi G, Filippi M
Neurology 2000 Jan 11;54(1):186-93
Scientific Institute, Ospedale San Raffaele, NeuroImaging Research Unit, Milan, Italy
PMID# 10636146; UI# 20100101
- The ability of Magnetization Transfer Ratio (MTR) Histogram analysis to detect the extent of changes occurring outside MS lesions seen on conventional scans
- Whether such changes vary in the different MS clinical phenotypes
- Whether the changes are associated with the extent and severity of the macroscopic Lesion Load
- The contribution to Brain Atrophy
Dual-echo, T1-weighted, and MT scans of the Brain were obtained from 77 patients with varying MS courses and 20 age- and sex-matched control subjects.
To create MT Histograms of the Normal-Appearing Cerebral Tissue, MS Lesions were segmented from dual-echo scans, superimposed automatically, and nulled out from the coregistered and scalp-stripped MTR maps.
Average MTR, peak height, and peak position were considered. T2 and T1 lesion loads, average lesion MTR, and Brain Volume were also measured.
Average Histogram MTR (p<0.0001) and peak position (p<0.0001) from patients with Relapsing/Remitting MS (RMMS) were lower than those from control subjects.
Patients with Primary/Progressive MS (PPMS) had lower average Histogram MTR (p = 0.002) and Histogram peak height (p = 0.01) than control subjects.
Patients with Secondary/Progressive MS (SPMS) had a lower peak height (p = 0.05) than those with RRMS. Average lesion MTR (p<0.0001) correlated highly with the Histogram MTR.
Average Histogram MTR (p<0.0001) and T2 lesion load (p = 0.001) correlated highly with Brain Volume.
The amount of microscopic changes account for an important fraction of the Lesion load in MS.
They may contribute to the development of Brain Atrophy and tend to be more evident in patients with Secondary/Progressive MS.
Correlations Between Clinical And MRI Involvement In Multiple Sclerosis: Assessment Using T1, T2 And MT Histograms
Iannucci G, Minicucci L, Rodegher M, Sormani MP, Comi G, Filippi M
J Neurol Sci 1999 Dec 15;171(2):121-9
Univ of Milan, Scientific Institute, Ospedale San Raffaele, Dept of NeuroScience, NeuroImaging Research Unit, Milan, Italy
PMID# 10581378; UI# 20050812
The degree of disability and Cerebellar and BrainStem impairments in Multiple Sclerosis (MS) patients were correlated with several Magnetic Resonance Imaging (MRI) measures of Tissue Damage.
In the whole Brain, Cerebellum and BrainStem to determine the relative contributions of the factors underlying the development of Disability in MS.
Dual-echo conventional Spin-Echo, T1-weighted and Magnetization Transfer (MT) scans were obtained from 72 patients with MS and 20 age- and sex-matched controls.
The following MRI-derived quantities were considered for the Brain as a whole, for the Cerebellum and for the BrainStem:
The number and volume of lesions seen on T1-weighted images;
The size of these structures measured on T1-weighted scans;
The average MT Ratio (MTR), peak height and peak position for the MT Histogram.
- The number and volume of lesions seen on T2-weighted images;
With univariate analysis, many MRI measures were significantly different in patients with different levels of Disability or Cerebellar and BrainStem Functional System Impairments.
However, with multivariate analysis, only Whole-Brain average MTR was significantly related to Physical Disability, while Cerebellar and BrainStem T1 lesion volume and average MTR were related to Cerebellar and BrainStem Impairment.
This study shows that increased pathological damage in clinically eloquent sites is the major cause of Disability in patients with MS.
It also suggests that measures derived from MT Histogram analysis and T1 HypoIntense lesion load should be considered when evaluating long-term MS evolution.
Brain Involvement In Systemic Immune Mediated Diseases: Magnetic Resonance And Magnetization Transfer Imaging Study
Rovaris M, Viti B, Ciboddo G, Gerevini S, Capra R, Iannucci G, Comi G, Filippi M
J Neurol NeuroSurg Psychiatry 2000 Feb;68(2):170-177
Hospital San Raffaele, NeuroImaging Research Unit, Dept of NeuroScience, Milan, Italy
PMID# 10644783; UI# 20112937
Magnetization Transfer Imaging (MTI) provides information about Brain damage with increased pathological specificity over conventional MRI and detects subtle abnormalities in the Normal-Appearing Brain Tissue, which go undetected with conventional scanning.
Brain MRI and MTI findings were compared in patients with Multiple Sclerosis (MS) and Systemic Immune Mediated Diseases (SIDs) affecting the CNS to investigate their roles in understanding the nature of Brain damage in these diseases.
Brain Dual Echo, T1 weighted and MTI scans were obtained in patients affected by Systemic Lupus Erithematosus (SLE) with (NSLE, n=9) and without clinical CNS involvement (n=15), Behcet's Disease (BD) (n=5), Wegener's Granulomatosis (WG) (n=9), and AntiPhosphoLipid Antibody Syndrome (APLAS) (n=6).
Ten patients with Clinically Definite MS and 15 healthy controls also underwent the same scanning protocol.
Brain MRI and MT Ratio (MTR) images of the same subject were coregistered and postprocessed to obtain MTR Histograms of the whole Brain and of the NABT.
Brain HyperIntense lesions were found in all patients with MS and with NSLE and in 5/15 patients with SLE, 5/9 with WG, 1/5 with BD, and 3/6 with APLAS.
The lesion burden in the Brain was significantly higher in patients with MS compared with all the other disease groups.
All MTR Histogram parameters were significantly different among patient subgroups.
Patients with MS had significantly lower average MTR than all except patients with NSLE and significantly lower peak height and location than patients with SLE patients with NSLE had significantly lower average MTR than patients with SLE.
Microscopic Brain tissue damage is relevant in patients with MS, but, apart from patients with NSLE, it seems to be absent in Systemic Immune Mediated Diseases.
Even in the presence of macroscopic MRI lesions or clinical evidence of CNS involvement.