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Accepted Manuscript
Title: The combined use of conventional MRI and MR
SpectroscopIC imaging increases the diagnostic accuracy in
amyotrophic lateral sclerosis
Author: Amedeo Cervo Sirio Cocozza Francesco Saccà Sara
M.d.A. Giorgio Vincenzo Brescia Morra Enrico Tedeschi
Angela Marsili Giovanni Vacca Vincenzo Palma Arturo
Brunetti Mario Quarantelli
PII:
DOI:
Reference:
S0720-048X(14)00503-8
http://dx.doi.org/doi:10.1016/j.ejrad.2014.10.019
EURR 6923
To appear in:
European Journal of Radiology
Received date:
Revised date:
Accepted date:
27-8-2014
21-10-2014
28-10-2014
Please cite this article as: Cervo A, Cocozza S, Saccà F, Giorgio SMdA, Morra VB,
Tedeschi E, Marsili A, Vacca G, Palma V, Brunetti A, Quarantelli M, The combined
use of conventional MRI and MR SpectroscopIC imaging increases the diagnostic
accuracy in amyotrophic lateral sclerosis, European Journal of Radiology (2014),
http://dx.doi.org/10.1016/j.ejrad.2014.10.019
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THE COMBINED USE OF CONVENTIONAL MRI AND MR SPECTROSCOPIC
IMAGING INCREASES THE DIAGNOSTIC ACCURACY IN AMYOTROPHIC
LATERAL SCLEROSIS
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Amedeo Cervo1*, Sirio Cocozza1*, Francesco Saccà2, Sara M.d.A. Giorgio1, Vincenzo Brescia
Morra2, Enrico Tedeschi1, Angela Marsili2, Giovanni Vacca2, Vincenzo Palma3, Arturo Brunetti1,
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These authors contributed equally to this work.
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*
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Mario Quarantelli4
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Highlights
We assessed in ALS the diagnostic accuracy of MRI signal and MRS data used alone and in
combination
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We found that T2-hypointensity and NAA decrease in motor cortex are two independent
phenomena
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These two variables taken alone do not provide acceptable diagnostic accuracy in ALS
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The same variables , when used in combination, improve the diagnostic accuracy of MRI in
ALS
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Department of Advanced Biomedical Sciences, University “Federico II”, Naples, Italy
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Department of Neurosciences, Reproductive Sciences and Odontostomatology, University
“Federico II”, Naples, Italy
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U.O.C. Neurofisiopatologia, PO S. Gennaro ASL Napoli 1, Naples, Italy
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Biostructure and Bioimaging Institute, National Research Council, Naples, Italy
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Corresponding author:
Sirio Cocozza, MD
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Department of Advanced Biomedical Sciences
University “Federico II”
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Via Pansini, 5
80131 - Naples - ITALY
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E-mail: siriococozza@hotmail.it
TEL +39 081 2203187 (ext -216)
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FAX +39 081 2296117
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MP +39 333 6078796
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Abstract
Purpose
We aimed to assess, in amyotrophic lateral sclerosis (ALS), the diagnostic accuracy of the
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combined use of conventional MRI signal changes (namely, hypointensity of the precentral cortex
and hyperintensity of the corticospinal tracts on T2-weighted images), and N-Acetyl-Aspartate
affected by limited diagnostic accuracy when used separately.
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Methods
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(NAA) reduction in the motor cortex at Magnetic Resonance Spectroscopy (MRS), which are
T2-hypointensity and NAA/(Choline+Creatine) ratio of the precentral gyrus and T2-hyperintensity
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of the corticospinal tracts were measured in 84 ALS patients and 28 healthy controls, using a
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Region-of-Interest approach.
Sensitivity and specificity values were calculated using Fisher stepwise discriminant analysis, and
Results
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cross-validated using the leave-one-out method.
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Precentral gyrus T2 signal intensity (p<10-4) and NAA peak (p<10-6) were significantly reduced in
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patients, and their values did not correlate significantly to each other both in patients and controls,
while no significant differences were obtained in terms of T2-hyperintensity of the corticospinal
tract. Sensitivity and specificity of the two discriminant variables, taken alone, were 71.4% and
75.0%, for NAA peak, and 63.1% and 71.4% for T2-hypointensity, respectively. When using these
two variables in combination, a significant increase in sensitivity (78.6%) and specificity (82.1%)
was achieved.
Conclusions
Precentral gyrus T2-hypointensity and NAA peak are not significantly correlated in ALS patients,
suggesting that they reflect relatively independent phenomena. The combined use of these measures
improves the diagnostic accuracy of MRI in ALS diagnosis.
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Introduction
Amyotrophic lateral sclerosis (ALS) is an idiopathic neurodegenerative disorder characterized by
selective degeneration of brain and spinal motor neurons controlling voluntary muscle movements .
mimicking conditions, particularly when bulbar onset occurs.
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In ALS diagnosis, brain Magnetic Resonance Imaging (MRI) is often performed to exclude other
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In the past years, several studies have shown different findings at conventional MRI in ALS
patients. These include increased signal of corticospinal tracts (CST) on T2-weighted images [1-4]
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(Figure 1) and reduced signal intensity of motor cortex on T2-weighted images [2, 5-7] (Figure 2).
Beside conventional MRI, advanced MR techniques have been introduced to investigate ALS
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patients, such as Magnetic Resonance Spectroscopy (MRS) or Diffusion Tensor Imaging (DTI).
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MRS consistently showed a reduction of N-Acetyl-Aspartate (NAA) in the primary motor cortex
and along the CST [8-11].
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More recently, 3D MRS acquisitions have allowed MRS measurements across the entire brain
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during a single scan, showing the possibility to follow neuronal loss along the CST [12].
On the other hand DTI measures have shown not only to be able to discriminate between controls
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and ALS patients, but even among different phenotypes, showing also a correlation with disease
severity [13].
Alongside with brain imaging in ALS, few studies investigated spinal cord abnormalities in ALS
patients (reviewed in [14]), showing alteration in both conventional (reduced cross-sectional area
and T1 hyperintensities in the antero-lateral columns) and DTI (lower mean fractional anisotropy)
acquisitions in the cervical spinal cord.
However, both conventional and advanced MR techniques do not provide a satisfactory level of
confidence about the diagnosis of ALS, and the few studies assessing the combined use of these
parameters were limited to small groups of patients [1, 15].
In the present study, we apply a multiparametric MR approach to assess the relationship between
these measures and the sensitivity and specificity of their combined use in ALS diagnosis. Our
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approach includes the evaluation, in the precentral gyrus (PCG), of the presence of T2
hypointensity (PCG-hypo) and of the NAA/(Choline+Creatine) ratio (PCG-NAA), and, along the
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CST, of the T2 hyperintensity (CST-hyper).
Methods
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Subjects
We retrospectively collected the MRI scans performed within the standard workup for ALS at our
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Institution from 2006 to 2013. Only patients fulfilling the criteria for a diagnosis of probable or
definite ALS according to El Escorial were included in the analysis.
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Additionally, a group of 28 healthy controls (HC) of comparable age and sex, who underwent an
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MRI study over the same time period and with the same acquisition protocol, was analysed.
Disease duration (DD) was measured based on the first occurrence of motor symptoms clearly
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related to the disease, as reported in clinical records.
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The revised ALS functional rating scale (ALSFRS-R) score, a measure of disease severity [16],
collected within two weeks from the MRI study, was available for all patients.
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Subjects with no history of neurological disorders or any other medical condition that could affect
the central nervous system were included in the HC group. Demographic information of patients
and HC data included in the study are listed in Table 1. This study was approved by the local Ethics
Committee.
MRI data acquisition
All MRI studies were acquired with identical protocol on a 3 Tesla MRI scanner (Trio, Siemens
Medical Systems, Erlangen, Germany).
The sequences used for the analysis included Fast Spin-Echo T2-weighted axial images and MRS
imaging, acquired with the same orientation.
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T2-weighted images had the following parameters: 25 axial slices, slice thickness = 4 mm, TE =
105 ms, TR = 4500 ms, echo train length= 13, acquisition matrix = 3842, FOV = 230x230 mm2.
2D multivoxel 1H-MRSI was performed using a spin-echo (point-resolved spectroscopy) sequence
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with water suppression by means of selective excitation (TE = 270ms, FOV = 160x160 mm2,
acquisition matrix = 16x16, thickness = 15mm, zero-filled to a voxel size of 5x5x15mm), acquiring
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a single axial slice, centered at the same level of the T2-weighted slice where hand “knobs” of the
motor cortex was best seen.
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During the MRI study the subjects were laying supine with the head fixed by straps and foam pads
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to minimize head movement.
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Conventional MRI analysis
T2-weighted images were analysed to assess PCG hypointensity and CST hyperintensity by using a
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set of pre-defined ROIs (see Figure 3 and Figure 4), placed in consensus by three trained raters (SC,
PCG-hypointensity evaluation
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AC, SMDAG), blinded to the clinical diagnosis.
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Pre- and post-central cortices were sampled on the T2-weighted axial slice in which the hand knob
of the motor cortex was best represented. For each exam, two linear ROIs were bilaterally handdrawn on the PCG and the postcentral gyrus of the selected slice using a 2-mm brush tool of a
commercial biomedical image processing software (Osirix 5.6 Pixmeo, Geneva, Switzerland;
www.osirix-viewer.com) (Figure 3).
These ROIs were placed within the cortical rim along the entire length of the central sulcus,
avoiding CSF.
As a measure of PCG hypointensity, the minimum pixel value in the corresponding ROI,
normalized by the mean value of the post-central ROI, was used. The use of ROI’s minimum value,
rather than the average value over the PCG ROI, has been chosen to assess the grade of PCG
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hypointensity, in order to avoid the confounding effect of both CSF and subcortical white matter
hyperintensities (e.g. gliosis) that could affect ROI mean values.
CST-hyperintensity evaluation
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To sample CST signal intensity, three circular ROIs (6 mm of diameter each) were bilaterally
placed along the course of each CST (one at the level of the cerebral peduncles, one in the posterior
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limb of the internal capsule and one in the subcortical white matter adjacent to the PCG), centered
on the relative local maxima. For each ROI, corresponding mean signal intensity was normalized by
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the mean value of a control ROI placed in the same slice on a structure apparently unaffected by the
disease [17] (Figure 4). For the evaluation of CST hyperintensity, we could not use a similar
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approach (i.e. measuring the maximum value of the ROI) to the one used for the PCG-hypo
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analysis, due to the presence of CST-neighboring structures with high-intensity signal, such as
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MRS analysis
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cisternal CSF, dilated Virchow-Robin spaces, and gliosis.
Spectroscopy data were analyzed using the software available on the scanner (Syngo MR B17,
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Siemens, Erlangen, Germany). Processing included Fourier transformation, Gaussian filtering in the
time domain, and phase and baseline correction, followed by peak identification of Choline (Cho,
centered at 3.22 ppm), creatine and phosphocreatine (Crea, 3.02 ppm), and NAA (2.02 ppm), and
fitting of the corresponding integrals under the curve.
To assess upper motor neuron (UMN) density/integrity, spectra from voxels immediately anterior to
the bilateral central sulci (Figure 5) were averaged. As the ratios of NAA to Crea and/or Cho have
been proposed as markers of UMN loss/dysfunction, in the present work we selected the ratio that
best discriminated the two populations for comparison with other MRI measures.
Statistics
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Student’s t-test was used to assess differences in age between HC and patients. Between-group
differences in gender were tested by the Chi-squared test.
As an influence of age has been previously suggested on CST-hyper, PCG-hypo and PCG-NAA in
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normal subjects [18-20], the significance of these correlations was tested in the HC group by
Spearman’s correlation coefficient.
AAO) was assessed in patients by Spearman's correlation coefficient.
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Correlation between the tested MR variables and the clinical data (ALSFRS, DD and age at onset -
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Sensitivity and specificity values, as well as the mean classification accuracy, were calculated to
show the predictive power of the combined MRI measures during the classification process, using
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Fisher stepwise discriminant analysis, and cross-validated using the leave-one-out method. During
remaining cases are treated as a new dataset
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the leave-one-out cross-validation, each case is extracted once and treated as test data, while the
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criterion.
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Fisher stepwise discriminant analysis was performed using Wilk’s Lambda as the chosen selection
All statistical analyses were performed using Statistical Package for Social Science (SPSS) package
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(SPSS Inc. Released 2007, Version 16.0. Chicago, SPSS Inc.).
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Results
ALS and HC groups were not significantly different for age and gender.
The NAA/(Cho+Crea) ratio proved to be the best measure to discriminate between the two
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populations (p<10-6 at Student’s t-test), compared to NAA/Cho (p<10-3) and NAA/Crea (p<10-4)
ratios. For this reason, this measure was used for the subsequent analysis as spectroscopic marker of
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neuronal loss.
No significant correlation emerged between any pair of the three tested variables neither in the HC
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nor in the ALS group, suggesting their relative independence.
PCG-NAA, PCG-hypo and CST-hyper measures in HC and ALS patients are reported in Table 2.
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misclassification of 7/28 HC (specificity 75.0%).
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PCG-NAA alone correctly classified 60/84 ALS patients (sensitivity 71.4%), with a
PCG-hypo alone correctly classified 53/84 ALS patients (sensitivity 63.1%), with a
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misclassification of 8/28 HC (specificity 71.4%).
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CST-hyper alone correctly classified 35/84 ALS patients (sensitivity 43.8%), with a
misclassification of 11/28 HC (specificity 60.7%).
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At Fisher stepwise discriminant analysis, only PCG-NAA and PCG-hypo were selected as able to
discriminate between SLA and HC subjects. Leave-one-out cross validation showed that when
PCG-NAA and PCG-hypo were used in combination, 66/84 subjects could be correctly classified as
ALS patients, providing a substantial increase in sensitivity (78.6%), with 5/28 HC showing an
abnormal value in at least one of the two measures (specificity 82.1%).
Sensitivity and specificity for each measure, and the overall accuracy of the method, are reported in
Table 3.
Finally, when testing the relationship between MR measures and clinical variables, only PCG-hypo
showed a significant correlation with ALSFRS-R (p<0.01; R=0.413).
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Discussion
ALS diagnosis can be challenging, especially in patients without clear symptoms and signs related
to the disease, or when other diseases/conditions (e.g. medullary compression due to spinal
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pathology) are present.
MRI is usually performed to exclude the possibility of other conditions known as “Motor neuron
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disease mimic” syndromes, including, but not limited to, cerebral or skull base lesions, cervical
spondylotic myelopathy, foramen magnum lesions, and syringomyelia [21].
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It has been proposed that MRI could provide additional relevant information, including findings
characteristic of ALS, although somewhat conflicting results have been reported.
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Hyperintensity of CST in T2-weighted images has been described in several studies [1-4].
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However, this signal modification has been shown to be not sensitive for ALS, with a frequency
ranging from 15% to 76% when compared to HC [22]and has been described not only in HC [4],
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but also in other neurological disorders, such as X-linked Charcot-Marie Tooth neuropathies,
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Krabbe disease, and adrenomyeloneuropathy [23-25]. Moreover, this finding does not correlate
with the clinical impairment [3].
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Cortical hypointensities located in the PCG in T2-weighted images have also been described in
several studies in ALS [2, 6, 7, 26], showing a correlation with the severity of the disease [5, 6, 15].
This modification, taken alone, is neither sensitive nor specific for ALS [22], due to its presence
both in normal aging [19] and in other neurological disorders, like Alzheimer’s disease, Parkinson’s
disease and multiple infarctions [26, 27]. The cause of this T2 shortening is still unclear. Several
studies have suggested a pathological iron accumulation in motor cortex microglia [6, 7], while
other authors do not agree with this hypothesis [28].
MRS has been also proposed as a useful adjunct to conventional MR sequences, to detect UMN loss
in ALS patients’ brains, resulting in a reduction of NAA. Several studies have detected a decreased
NAA concentration in ALS, especially in PCG [8-11, 29], which appears to be correlated with the
disease severity [9, 30].
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In the present study MRS imaging data were analyzed. This approach was chosen, compared to
single-voxel MRS, as the shape and the extension of the motor cortex makes it suitable for a
technique that allows for convoluted sampling across the plane. In addition, given the bilaterality of
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the disease, as multivoxel MRS allows to assess neuronal loss in different brain subregions
simultaneously, the possibility to average left and right values allowed a substantial increase in the
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S/N ratio.
Recently, MRS alterations in cervical cord have been shown in presymptomatic SOD1-positive
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people, at risk for familial ALS [31], witnessing the potential of this approach to derive a biomarker
for ALS diagnosis and progression.
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Combination of different MR techniques is a promising way to increase confidence in ALS
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diagnosis. To our knowledge, this is the first study that combines T2-weighted hypointensity of
motor cortex and MRS data, with the aim of evaluating their diagnostic efficiency, both alone and
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in combination, in a large group of ALS patients.
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Few studies have assessed the combined use of conventional and advanced MR measures in ALS
diagnosis. Sarchielli et al assessed both PCG-hypo and NAA in the motor cortex [15], although the
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specificity of PCG-hypo was not tested. Instead, Charil and colleagues reported a 100% sensitivity
and specificity when combining CST hyperintensity on FLAIR images and NAA/Crea ratio,
although these results were obtained in a group of only 11 patients [1].
We chose to combine PCG-hypo and PCG-NAA because, in our data sets, these two measures
proved to be relatively independent and capable of discriminating the two groups. It is noteworthy
that the lack of correlation between these two measures has been inconstantly reported. Previous
works in smaller patient groups have either shown [15] or failed to detect [5] significant differences
in NAA in the motor cortex between patients with and without cortical hypointensities in the PCG.
As previous studies have linked PCG-hypo to iron accumulation mainly in the microglia [6], we
speculate that this lack of correlation between PCG-hypo and PCG-NAA could be explained by the
presence of a different time course of PCG-NAA decrease (an early phenomenon, reflecting UMN
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loss or dysfunction), compared to iron accumulation (possibly related to inflammatory phenomena
secondary to microglial migration and activation), which leads to detectable PCG-hypo at a later
time point.
longitudinal studies with both techniques should be carried out.
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To fully elucidate the temporal relationship between PCG-hypo and PCG-NAA over time,
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The sensitivity and specificity of PCG-hypo and PCG-NAA, which was low when the two variables
were taken alone, significantly increased when they were used in combination. Therefore, in
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patients undergoing an MRI study for possible ALS, beside the assessment of T2-hypointensity in
the motor cortex, the use of MRS can ameliorate sensitivity, at the expenses of a limited increase in
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scanning time.
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In agreement with the high variability of CST-hyperintensity reported in the literature [22], we
found no significant differences between ALS patients and HC; this could be explained both by the
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low specificity of this finding, known to be present also in normal aging [20], and by the use of
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FSE-T2-weighted images, whose sensitivity has been reported to vary from 14% to 63%[1].
To reduce the reportedly high variability of conventional MRI findings, probably due to the use of
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qualitative evaluation of absence/presence or grading of a specific sign based on subjective
assessment [22], we chose a ROI-based semiquantitative approach, slightly more time-consuming,
but more reproducible.
The use of ROI’s minimum value for the analysis of PCG-hypo, although in general noisier than
mean values, permitted to avoid the confounding effect of both CSF and subcortical white matter
hyperintensities (e.g. gliosis) that could affect ROI mean values. A possible future expansion of the
current approach may be the use of a measure of the skewness of the distribution of the values of
the voxels in the ROI, which may provide a less noisy measure of the PCG hypointensity.
Previous studies showed a correlation between the severity of the disease and PCG-NAA [9, 30].
Conversely, we did not find a significant relationship between clinical data and this variable,
possibly due to methodological differences, such as the correction of our values for age (as it
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correlates both with clinical data and MRI findings), or the use of ALSFRS, which has been
reported to be unrelated to MRS data [15, 32].
Finally, some limitations should be considered in the present report. First, the retrospective nature
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of this study prevented the use of axial FLAIR images, which were not included in the standard
workup for ALS patients at our institution. FLAIR images may be more sensitive in showing CST
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hyperintensity in ALS [3], although it is noteworthy that direct comparison of FSE-T2-weighted
and FLAIR images has shown this to be at least partly compensated by a lower specificity of
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FLAIR sequence [5].
Secondly, other advanced techniques proposed as promising instruments for ALS diagnosis have
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not been included here.
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In particular, DTI analysis has demonstrated microstructural alterations not only along the CST,
specifically at the level of the posterior limb of the internal capsule, but also in other WM regions
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[33, 34], including the cervical spinal cord, with significant correlation with the clinical scores [13,
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35]. Moreover, using magnetization transfer imaging, further microstructural modifications have
been described both in the precentral gyrus and in extramotor areas [36]. However, as also these
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techniques appear to lack an acceptable diagnostic accuracy when taken alone [37], it remains to be
tested whether they are relatively independent from the more diffuse MRI measures used in the
present work, and to evaluate whether their inclusion in the proposed diagnostic setup could further
increase MRI accuracy in ALS diagnosis.
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Conclusions
In conclusion, our findings suggest that T2-hypointensity and NAA decrease in the motor cortex,
assessed by a semiquantitative analysis, reflect two independent phenomena in ALS. These two
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be combined to improve the diagnostic accuracy of MRI in ALS.
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variables, which taken alone do not provide acceptable diagnostic accuracy in ALS diagnosis, can
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Conflict of Interest
All authors do not have any financial and personal relationships with other people or organizations
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that could inappropriately influence (bias) our work.
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Role of the Funding Source
The Funding Source had no involvement in study design, interpretation of data and in the writing of
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the article.
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Figure legends
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Figure 1. Corticospinal tract hyperintensities in ALS.
Signal alterations along the corticospinal tracts in T2-weighted axial TSE images, in the ALS
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patient with the highest CST-Hyper value (bottom, 58yo male, 3 month disease duration), compared
to a 55yo male HC (top).
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Sections through cerebral peduncles (left) and internal capsule (right) are shown.
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Hyperintensity of the corticospinal tract can be clearly appreciated at both levels in the patient. At
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the same levels, only a mild hyperintensity can be also seen in the HC images.
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Figure 2. Precentral gyrus hypointensity in ALS.
Hypointensities along the precentral cortex in T2-weighted axial TSE images, in two ALS patients,
compared with an age/ and sex/ matched HC.
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A significant hypointensity of the motor cortex can be clearly appreciated in the patient more
severely impaired (on the right, 67yo female with 17 month disease duration, ALSFRS-R 19),
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compared to both the HC (on the left, 68yo female) and an early stage patient with shorter disease
duration (in the middle, 68yo female with 3 month disease duration, ALSFRS-R 36).
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Sections at the level of the hand knobs of the motor cortex are shown.
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Figure 3. Pre- and post-central gyrus ROIs for conventional MRI analysis.
T2-weighted axial image at the level of the hand knob of the motor cortex with (A) and without (B)
the two superimposed hand-drawn ROIs used for the assessment of PCG-hypo (red) and of the
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mean post-central gyrus signal intensity (green). ROIs were drawn using a 2mm-brush tool along
the entire length of the central sulcus, avoiding CSF. Relative T2-hypointensity of the PCG can be
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appreciated.
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Figure 4. Corticospinal tract ROI positioning.
Selected T2-weighted images at the level of the cerebral peduncles (A), posterior limb of the
internal capsule (B) and the hand knob of the motor cortex (C), with superimposed ROIs placed on
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the CST (in red), and the corresponding ROIs used for data normalization (in green), placed within
the midbrain tegmentum (A), in the splenium of the corpus callosum (B) and in the postcentral
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gyrus (C).
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Figure 5. Precentral gyri spectrum with corresponding MRS slab.
Representative spectrum from the precentral regions at the level of the hand knobs in both a 50yo
female HC (top) and a 48yo female ALS patient (bottom).
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On the right, for each subject, the multivoxel MRS sampling grid is shown superimposed on the
T2-weighted axial image corresponding to the center of the MRS slab, along with coronal and
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sagittal localizers for reference.
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A clear reduction in the NAA/(Cho+Crea) ratio can be appreciated in the patient.
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Table 1. Subjects demographics and clinical variables.
HC: healthy controls; ALS: amyotrophic lateral sclerosis; SD: standard deviation; ALSFRS-R:
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amyotrophic lateral sclerosis functional rating scale revised; n/a: not applicable; DD: disease
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duration; AAO: age at onset. Ages and DD are in years.
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Table 2. PCG-Hypo, PCG-Hyper and PCG-NAA values.
PCG-NAA: NAA/Cho+Crea ratio in the precentral gyrus; PCG-hypo: signal intensity of the
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precentral gyrus; PCG-hyper MC: signal intensity of the white matter at the level of the motor
cortex; PCG-hyper IC: signal intensity of the white matter at the level of the posterior limb of the
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internal capsule; PCG-hyper CP: signal intensity of the white matter at the level of the cerebral
peduncles.
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For each measure, mean±standard deviation is reported, along with the significance of the
difference between HC and ALS patients at Mann/Whitney test.
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n.s.: not significant
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Table 3. Diagnostic accuracies of PCG-NAA, PCG-hypo and their combined use in ALS patients.
PCG-NAA: NAA/Cho+Crea ratio in the precentral gyrus; PCG-hypo: signal intensity of the precentral gyrus; CST-hyper: signal intensity along the
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corticospinal tract.
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Acknowledgements
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This study was partly supported by the Italian Ministry of Education, University, and Research (MIUR) with a grant (PRIN 2010-2011 -
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2010XE5L2R_001) to E.T.
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Table 1.
ALS
Age (mean±SD)
57.5±13.9 (range 29-80)
61.1±11.2 (range 28-81)
Sex (M/F)
12/16
ALSFRS-R (median)
n/a
DD (mean±SD)
n/a
AAO (mean±SD)
n/a
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HC
52/32
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1.5±1.4
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59.6±11.3 (range 27-80)
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Table 2.
PCG-NAA
1.35±0.13
1.19±0.14
PCG-hypo
0.65±0.7
0.56±0.10
PCG-hyper MC
0.99±0.6
1.02±0.15
PCG-hyper IC
1.25±0.15
1.26±0.14
PCG-hyper CP
0.85±0.09
0.81±0.09
p<10-6
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p<10-4
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HC
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Sensitivity
Specificity
Overall accuracy
PCG-NAA
60/84 (71.4%)
21/28 (75.0%)
81/112 (72.3%)
PCG-hypo
53/84 (63.1%)
20/28 (71.4%)
73/112 (65.1%)
CST-hyper
35/84 (43.8%)
17/28 (60.7%)
52/112 (46.4%)
Combined
66/84 (78.6%)
23/28 (82.1%)
89/112 (79.4%)
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Table 3.
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