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1.
Schweiz Arch Tierheilkd ; 165(9): 573-584, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37646097

ABSTRACT

INTRODUCTION: This study aimed to describe equine transportation practices and transport-related behavioural and health problems in Switzerland and to identify possible associations between them. An online survey was disseminated to Swiss equine industry members and questioned respondents' details, transport practices (before, during, and after journeys), horse transport-related behavioural (TRPBs) and health problems (TRHPs) experienced in the previous 2 years. The survey generated 441 valid responses, analysed using descriptive statistics and logistic regression models (outcomes: TRPBs, TRHPs, injuries, diarrhea). Respondents were mainly women (79,5 %), younger than 50 years (75 %), and amateurs (80 %). Most of the respondents transported one or two horses (88,7 %), for a short (< 2 hours) journey (75,5 %). Pre-transport practices were performed by 72,1 % of respondents and horses' fitness for travel was assessed in the majority of cases (66,5 %). During the journey, horses were tethered (92,6 %) and monitored (52,7 %). The majority of respondents (74,9 %) assessed also the horses' fitness after travel. TRPBs were reported by 13,4 % of respondents. TRPBs' likelihood increased when the respondents were women, performed pre-transport practices and training for transport, did not assess drinking behaviour and general health before journey, and the horses experienced also TRHPs. TRHPs were reported by 34 % of the respondents and were associated with younger respondents, use of trucks, doing pre-transport practices, wearing protections, not monitoring horses during transport and preexisting TRPBs. Among TRHPs the most frequent were injuries (72,1 %) and diarrhea (41 %). The likelihood of injuries increased with younger respondents, use of trucks, wearing protections, lack of monitoring during transport and TRPBs. While younger respondents, longer journeys, wearing protections, lack of monitoring during transport, measuring rectal temperature after journeys and TRPBs increased the odds of reporting diarrhea. Even though our findings must be interpreted with caution due to survey limitations, considering that the found associations do not always mean causation, they highlight the strengths and weaknesses of transport practices in Switzerland and report evidence to implement current regulations on the protection of horse welfare during transport.


INTRODUCTION: Cette étude a pour but de décrire les pratiques de transport de chevaux et les problèmes de comportement et de santé liés à ces transports en Suisse et d'identifier les associations possibles entre ces deux éléments. Une enquête en ligne a été diffusée auprès des membres de la filière équine suisse et a permis de recueillir les coordonnées des répondants, les pratiques de transport (avant, pendant et après les trajets), les problèmes de comportement (TRPB) et de santé liés (TRHP) au transport des chevaux rencontrés au cours des deux années précédentes. L'enquête a généré 441 réponses valides, analysées à l'aide de statistiques descriptives et de modèles de régression logistique (résultats: TRPB, TRHP, blessures, diarrhée). Les répondants étaient principalement des femmes (79,5 %), âgées de moins de 50 ans (75 %) et amateurs (80 %). La plupart des personnes interrogées ont transporté un ou deux chevaux (88,7 %), pour un trajet court (< 2 heures) (75,5 %). Des mesures préalables au transport ont été prises par 72,1 % des répondants et l'aptitude des chevaux au voyage a été évaluée dans la majorité des cas (66,5 %). Pendant le voyage, les chevaux étaient attachés (92,6 %) et surveillés (52,7 %). La majorité des répondants (74,9 %) ont également évalué l'état des chevaux après le voyage. Des cas de TRPB ont été signalés par 13,4 % des répondants. La probabilité de TRPB augmente lorsque les personnes interrogées sont des femmes, qu'elles ont pris des mesures préalables au transport et ont entraîné le transport, qu'elles n'ont pas évalué le comportement d'abreuvement et l'état de santé général avant le voyage et que les chevaux ont souffert de TRHP. Les TRHP ont été signalées par 34 % des personnes interrogées et ont été associées à des personnes plus jeunes, à l'utilisation de camions, aux mesures préalables au transport, au port de protections, à l'absence de surveillance des chevaux pendant le transport et à des TRPB préexistantes. Parmi les TRHP, les plus fréquentes étaient les blessures (72,1 %) et la diarrhée (41 %). La probabilité de blessures augmente avec la jeunesse des répondants, l'utilisation de camions, le port de protections, l'absence de surveillance pendant le transport et la présence de TRPB. En revanche, les répondants plus jeunes, les trajets plus longs, le port de protections, l'absence de contrôle pendant le transport, la mesure de la température rectale après les trajets et les TRPB augmentent la probabilité de déclarer une diarrhée. Même si nos résultats doivent être interprétés avec prudence en raison des limites de l'enquête, considérant que les associations trouvées ne signifient pas toujours une causalité, ils soulignent les forces et les faiblesses des pratiques de transport en Suisse et rapportent des preuves pour mettre en œuvre les réglementations actuelles sur la protection du bien-être des chevaux pendant le transport.


Subject(s)
Diarrhea , Transportation , Female , Horses , Animals , Male , Switzerland , Diarrhea/veterinary
3.
J Physiol ; 589(Pt 5): 1159-72, 2011 Mar 01.
Article in English | MEDLINE | ID: mdl-21224221

ABSTRACT

Astrocytes in the barrel cortex respond with a transient Ca2+ increase to neuronal stimulation and this response is restricted to the stimulated barrel field. In the present study we suppressed the astrocyte response by dialysing these cells with the Ca2+ chelator BAPTA. Electrical stimulation triggered a depolarization in stellate or pyramidal 'regular spiking' neurons from cortex layer 4 and 2/3 and this response was augmented in amplitude and duration after astrocytes were dialysed with BAPTA. Combined blockade of GABAA and GABAB receptors mimicked the effect of BAPTA dialysis, while glutamate receptor blockers had no effect. Moreover, the frequency of spontaneous postsynaptic currents was increased after BAPTA dialysis. Outside the range of BAPTA dialysis astrocytes responded with a Ca2+ increase, but in contrast to control, the response was no longer restricted to one barrel field. Our findings indicate that astrocytes control neuronal inhibition in the barrel cortex.


Subject(s)
Astrocytes/metabolism , Neural Inhibition/physiology , Neurons/metabolism , Somatosensory Cortex/metabolism , gamma-Aminobutyric Acid/metabolism , Action Potentials/drug effects , Action Potentials/physiology , Animals , Astrocytes/drug effects , Calcium Signaling/drug effects , Calcium Signaling/physiology , Egtazic Acid/analogs & derivatives , Egtazic Acid/pharmacology , Electric Stimulation , GABA-B Receptor Antagonists/pharmacology , Immunohistochemistry , Mice , Mice, Transgenic , Nerve Net/drug effects , Nerve Net/metabolism , Neural Inhibition/drug effects , Neurons/drug effects , Patch-Clamp Techniques , Phosphinic Acids/pharmacology , Propanolamines/pharmacology , Pyridazines/pharmacology , Receptors, GABA-A/metabolism , Receptors, GABA-B/metabolism , Somatosensory Cortex/drug effects
4.
AJNR Am J Neuroradiol ; 32(1): 204-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20966065

ABSTRACT

BACKGROUND AND PURPOSE: Neuro-axonal damage is a well known sequelae of MS pathogeneses. Consequently, our aim was to test whether the ∼20% of patients with MS exhibiting a clinically benign disease course also have minimal neural dysfunction as reflected by the global concentration of their MR imaging marker NAA. MATERIALS AND METHODS: Q(NAA) was obtained with nonlocalizing whole-head (1)H-MR spectroscopy in 43 patients with benign RRMS (30 women, 13 men; mean age, 44.7 ± 7.3 years of age) with 21.0 ± 4.4 years (range, 15-35 years) of disease duration from the first symptom and an EDSS score of 1.9 (range, 0-3). Q(NAA) was by divided by the brain volume (from MR imaging segmentation) to normalize it into WBNAA. All participants gave institutional review board-approved written informed consent, and the study was HIPAA compliant. RESULTS: The patients' lesion load was 12.2 ± 7.7 cm(3). Their 8.3 ± 1.8 mmol/L WBNAA was 35% lower than that in controls (P < .001). Individual average loss rates (absolute loss compared with controls divided by disease duration) clustered around 0.22 ± 0.09 mmol/L/year (1.7%/year, assuming monotonic decline). This rate could be extrapolated from that already reported for patients with RRMS of much shorter disease duration. WBNAA did not correlate with lesion load or EDSS. CONCLUSIONS: Normal WBNAA is not characteristic of benign MS and is not an early predictor of its course. These patients, therefore, probably benefit from successful compensation and sparing of eloquent regions. Because they may ultimately have a rapid decline once their brain plasticity is exhausted, they may benefit from treatment options offered to more affected patients.


Subject(s)
Aspartic Acid/analogs & derivatives , Brain/metabolism , Magnetic Resonance Spectroscopy/methods , Multiple Sclerosis/metabolism , Adolescent , Adult , Aspartic Acid/metabolism , Down-Regulation , Female , Humans , Male , Protons , Tissue Distribution , Young Adult
5.
J Neurol Neurosurg Psychiatry ; 81(1): 26-30, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19546104

ABSTRACT

BACKGROUND: Diffusion tensor (DT) MRI enables quantification of the severity of brain and cervical cord pathology in multiple sclerosis (MS). OBJECTIVE: To investigate DT MRI patterns of cervical cord damage in patients with benign MS (BMS) and secondary progressive MS (SPMS), in order to achieve a better understanding of the mechanisms underlying the development of irreversible disability in MS. METHODS: Conventional and DT MRI scans of the cervical cord and brain were acquired from 40 BMS patients, 28 SPMS patients and 18 healthy individuals. Cervical cord and brain mean diffusivity (MD) and fractional anisotropy (FA) maps were created and average MD and FA were calculated. Cross sectional cord area (CSA) was also computed. RESULTS: 37 (92%) BMS patients and all (100%) SPMS patients had macroscopic cervical cord lesions. Compared with healthy individuals, BMS patients had higher average cord MD while SPMS patients had higher average cord MD, lower average cord FA and lower average CSA. Compared with BMS patients, SPMS patients had lower cord average FA and lower average CSA. In MS patients, Expanded Disability Status Scale (EDSS) was correlated with CSA (r = -0.47, p<0.0001), average cord FA (r = -0.37, p = 0.002) and brain T2 lesion volume (LV) (r = 0.34, p = 0.005). A multivariate regression model identified CSA, average cord FA and brain T2 LV as variables independently influencing the EDSS score (r = 0.58, p<0.0001). CONCLUSIONS: Cervical cord damage outside focal macroscopic lesions is limited in patients with BMS. The assessment of cord and brain pathology provides complementary information to improve the understanding of disability accumulation in MS.


Subject(s)
Diffusion Tensor Imaging , Multiple Sclerosis, Chronic Progressive/pathology , Multiple Sclerosis/pathology , Spinal Cord/pathology , Adult , Brain/pathology , Disability Evaluation , Female , Humans , Male , Middle Aged
6.
Mult Scler ; 15(7): 789-94, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19465450

ABSTRACT

OBJECTIVE: The term benign multiple sclerosis (BMS) is referred to patients who have a mild or absent disability several years after disease clinical onset. Axonal damage can be measured in vivo using proton MR spectroscopy ((1)H-MRS). In this study, we quantified the severity of "global" axonal damage in BMS and early relapsing-remitting (RR) MS patients, using whole brain N-acetylaspartate (WBNAA) (1)H-MRS, to better elucidate the structural correlates of a non-disabling disease evolution. METHODS: WBNAA concentration was measured in 37 patients with BMS (mean disease duration 22.3 years) and 17 patients with early RRMS (mean disease duration 4.0 years), using an unlocalized (1)H-MRS sequence. Dual echo and T1-weighted scans were also obtained to measure T2-hyperintense lesion volume (TLV) and normalized brain volume (NBV). RESULTS: TLV was higher in BMS (mean TLV = 13.1 mL) than in early RRMS patients (mean TLV = 7.2 mL) (P = 0.018), whereas neither NBV (mean NBV: 1491.0 mL in BMS vs 1520.3 mL in RRMS) nor WBNAA concentration (mean WBNAA: 10.5 mmol in BMS vs 11.4 mmol in RRMS) significantly differed between the two groups. In MS patients, no correlation was found between WBNAA concentration and Expanded Disability Status Scale (EDSS), TLV and NBV. CONCLUSIONS: The similar WBNAA concentrations seen in BMS and early RRMS patients fit with the notion that a non-disabling long-term evolution of MS may be due, at least in part, to non-progression of pathology. Such a condition seems to be independent from MRI-visible lesions burden.


Subject(s)
Aspartic Acid/analogs & derivatives , Axons/pathology , Brain Chemistry , Brain/pathology , Multiple Sclerosis, Relapsing-Remitting/pathology , Multiple Sclerosis/pathology , Adult , Aspartic Acid/analysis , Axons/chemistry , Biomarkers/analysis , Brain/metabolism , Cell Survival , Cross-Sectional Studies , Disability Evaluation , Disease Progression , Female , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Middle Aged , Multiple Sclerosis/metabolism , Multiple Sclerosis, Relapsing-Remitting/metabolism , Severity of Illness Index , Young Adult
7.
AJNR Am J Neuroradiol ; 28(9): 1650-1, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17893213

ABSTRACT

Although the concentration of N-acetylaspartate (NAA) is often used as a neuronal integrity marker, its normal temporal variations are not well documented. To assess them over the 1-2 year periods of typical clinical trials, the whole-brain NAA concentration was measured longitudinally, over 4 years, in a cohort of healthy young adults. No significant change (adjusted for both sex and age) was measured either interpersonally or intrapersonally over the entire duration of the study.


Subject(s)
Aspartic Acid/analogs & derivatives , Brain/metabolism , Magnetic Resonance Spectroscopy/methods , Adolescent , Adult , Aspartic Acid/analysis , Female , Humans , Longitudinal Studies , Male , Middle Aged , Protons , Reference Values , Reproducibility of Results , Sensitivity and Specificity
8.
AJNR Am J Neuroradiol ; 28(1): 72-5, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17213427

ABSTRACT

BACKGROUND AND PURPOSE: Radiologic markers in multicenter trials are often confounded by different instrumentation used. Our goal was to estimate the variance of the global concentration of the neuronal cell marker N-acetylaspartate (NAA) among research centers using MR imaging scanners of different models, from different manufacturers, and of different magnetic field strength. MATERIALS AND METHODS: Absolute millimolar amounts of whole-brain NAA (WBNAA) were quantified with nonlocalizing proton MR spectroscopy in the brains of 101 healthy subjects (53 women, 48 men) aged 16-59 years (mean, 34.2 years). Twenty-three were scanned at 1 institute in a 1.5T Siemens Vision; 31 from another institute were studied with a 1.5T Siemens SP63; 36 were scanned at a third institute (24 with a 1.5T Vision, 12 with a 3T Siemens Trio); and 11 were obtained at a fourth institute using a 4T GE Signa 5.x. The NAA amounts were quantified with phantom-replacement and divided by the brain volume, segmented from MR imaging, to yield the concentration, a metric independent of brain size suitable for cross-sectional comparison. RESULTS: The average WBNAA concentration among institutions was 12.2 +/- 1.2 mmol/L. The subjects' WBNAA distributions did not differ significantly (p > .237) among the 4 centers, regardless of scanner manufacturer, model, or field strength and irrespective of whether adjustments were made for age or sex. CONCLUSION: Absolute quantification against a standard makes the WBNAA concentration insensitive to the MR hardware used to acquire it. This important attribute renders it a robust surrogate marker for multicenter neurologic trials.


Subject(s)
Aspartic Acid/analogs & derivatives , Brain/pathology , Magnetic Resonance Imaging/instrumentation , Magnetic Resonance Spectroscopy/instrumentation , Adolescent , Adult , Aspartic Acid/analysis , Cohort Studies , Equipment Design , Female , Humans , Male , Middle Aged , Reference Standards , Reproducibility of Results
9.
J Neurol Neurosurg Psychiatry ; 78(5): 480-4, 2007 May.
Article in English | MEDLINE | ID: mdl-17030586

ABSTRACT

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with severe cervical cord damage due to degeneration of the corticospinal tracts and loss of lower motor neurones. Diffusion tensor magnetic resonance imaging (DT MRI) allows the measurement of quantities reflecting the size (such as mean diffusivity) and orientation (such as fractional anisotropy) of water-filled spaces in biological tissues. METHODS: Mean diffusivity and fractional anisotropy histograms from the cervical cord of patients with ALS were obtained to: (1) quantify the extent of tissue damage in this critical central nervous system region; and (2) investigate the magnitude of the correlation of cervical cord DT MRI metrics with patients' disability and tissue damage along the brain portion of the corticospinal tracts. Cervical cord and brain DT MRI scans were obtained from 28 patients with ALS and 20 age-matched and sex-matched controls. Cord mean diffusivity and fractional anisotropy histograms were produced and the cord cross-sectional area was measured. Average mean diffusivity and fractional anisotropy along the brain portion of the corticospinal tracts were also measured. RESULTS: Compared with controls, patients with ALS had significantly lower mean fractional anisotropy (p = 0.002) and cord cross-sectional area (p<0.001). Mean diffusivity histogram-derived metrics did not differ between the two groups. A strong correlation was found between mean cord fractional anisotropy and the ALS Functional Rating Score (r = 0.74, p<0.001). Mean cord and brain fractional anisotropy values correlated moderately (r = 0.37, p = 0.05). CONCLUSIONS: Cervical cord DT MRI in patients with ALS allows the extent of cord damage to be graded. The conventional and DT MRI changes found are compatible with the presence of neuroaxonal loss and reactive gliosis, with a heterogeneous distribution of the pathological process between the brain and the cord. The correlation found between cord fractional anisotropy and disability suggests that DT MRI may be a useful adjunctive tool to monitor the evolution of ALS.


Subject(s)
Amyotrophic Lateral Sclerosis/complications , Brain/pathology , Diffusion Magnetic Resonance Imaging , Disability Evaluation , Pyramidal Tracts/pathology , Adult , Aged , Anisotropy , Case-Control Studies , Female , Humans , Male , Middle Aged
10.
Brain ; 129(Pt 10): 2628-34, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16921179

ABSTRACT

Reliable prognostic markers of primary progressive (PP) multiple sclerosis evolution are still needed. Diffusion tensor (DT) MRI can quantify normal-appearing white matter (NAWM) and grey matter (GM) damage in multiple sclerosis patients. We investigated whether conventional and DT-MRI-derived measures can predict the long-term clinical evolution of PP multiple sclerosis. In 54 PP multiple sclerosis patients, conventional and DT-MRI scans of the brain and T1-weighted scans of the cervical cord were acquired at baseline and after a median follow-up of 15 months. Another clinical evaluation was performed, 56 months after baseline, in 52 patients. Measures of lesion load, brain and cord atrophy were obtained. Histograms of the mean diffusivity (MD) and fractional anisotropy (FA) values from the NAWM and GM were analysed. At follow-up, 35 patients (65%) experienced a confirmed disability progression. Baseline expanded disability status scale score and average GM MD were independent predictors of subsequent clinical deterioration in a multivariable model (Nagelkerke R2: 0.44; discriminating ability: 81%). A lower level of disability and a more severe GM damage identify PP multiple sclerosis patients with an increased risk of disease progression over the subsequent 5 years. These data may be relevant to select patients for future exploratory phase II trials.


Subject(s)
Brain/pathology , Image Interpretation, Computer-Assisted , Magnetic Resonance Imaging , Multiple Sclerosis, Chronic Progressive/pathology , Adult , Aged , Cervical Vertebrae , Disease Progression , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Middle Aged , Multivariate Analysis , Prognosis , ROC Curve , Sensitivity and Specificity , Spinal Cord/pathology
11.
Neurology ; 67(1): 161-3, 2006 Jul 11.
Article in English | MEDLINE | ID: mdl-16832101

ABSTRACT

The authors assessed the ability of diffusion tensor MRI to grade cervical cord damage in 10 patients with neuromyelitis optica, 10 patients with multiple sclerosis, and 10 healthy controls. The three groups differed in terms of average mean diffusivity (p = 0.008) and average fractional anisotropy (p = 0.04). There was a correlation between the Expanded Standard Disability Status Scale score and cord average mean diffusivity (r = 0.52, p = 0.02).


Subject(s)
Diffusion Magnetic Resonance Imaging , Multiple Sclerosis/pathology , Neuromyelitis Optica/pathology , Spinal Cord/pathology , Adult , Analysis of Variance , Anisotropy , Case-Control Studies , Disability Evaluation , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Statistics as Topic
12.
AJNR Am J Neuroradiol ; 27(4): 892-4, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16611786

ABSTRACT

BACKGROUND AND PURPOSE: Neuroborreliosis is frequently indistinguishable from multiple sclerosis (MS) on both clinical and radiologic grounds. By using MR imaging, we assessed "occult" brain white matter (WM), brain gray matter (GM), and cervical cord damage in patients with neuroborreliosis in an attempt to achieve a more accurate picture of tissue damage in these patients, which might contribute to the diagnostic work-up. METHODS: We studied 20 patients with neuroborreliosis and 11 sex- and age-matched control subjects. In all subjects, we acquired dual echo, T1-weighted, diffusion tensor (DT) and magnetization transfer (MT) MR imaging scans of the brain and fast short-tau inversion recovery and MT MR imaging scans of the cervical cord. T2-visible lesion load was measured by using a local thresholding segmentation technique. Mean diffusivity and fractional anisotropy histograms of the brain and cervical cord MT ratio histograms were produced. Normalized brain volumes (NBV) were measured by using SIENAx. RESULTS: Brain T2-visible lesions were detected in 12 patients, whereas no occult damage in the normal-appearing WM and GM was disclosed by using MT and DT MR imaging. No macroscopic lesions were found in the cervical cord, which was also spared by occult pathology. NBV did not differ between patients with neuroborreliosis and control subjects. CONCLUSION: This study shows that, contrary to what happens in MS, occult brain tissue damage and cervical cord pathology are not frequent findings in patients with neuroborreliosis. These observations might be useful in the diagnostic work-up of patients with neuroborreliosis and T2 brain lesions undistinguishable from those of MS.


Subject(s)
Brain Diseases/diagnosis , Brain Diseases/microbiology , Lyme Neuroborreliosis/diagnosis , Magnetic Resonance Imaging , Spinal Cord Diseases/diagnosis , Spinal Cord Diseases/microbiology , Adult , Female , Humans , Male , Middle Aged
13.
Neurology ; 66(4): 535-9, 2006 Feb 28.
Article in English | MEDLINE | ID: mdl-16505308

ABSTRACT

BACKGROUND: Conventional MRI can reveal decreases in brain volumes with aging but fails to provide information about the underlying microstructural modifications. Magnetization transfer (MT) and diffusion tensor (DT) MRI can in part overcome these limitations. OBJECTIVE: To investigate the influence of aging on conventional and MT and DT MRI-derived measurements in brain white (WM) and gray (GM) matter. METHODS: Dual-echo, T1-weighted, MT and DT MR images of the brain were obtained in 89 healthy subjects (age range 11 to 76 years). Normalized GM and WM volumes were measured and MT ratio (MTR) and mean diffusivity (MD) histograms produced for both tissue compartments. RESULTS: Normalized brain (r = -0.78), GM (r = -0.75), and WM (r = -0.34) volumes and the number of brain T2 hyperintensities (r = 0.49) were correlated with age. Additionally, all GM MT- and DT-derived parameters also correlated with age (r values ranging from 0.28 to 0.64), whereas only the peak height (ph) of the normal-appearing (NA) WM MD histogram did so (r = -0.34). After correcting for the number of T2 hyperintensities, gender, and the corresponding normalized tissue volumes, only the correlations between age and GM average MD (r = 0.24), GM-MD-ph (r = -0.37), and NAWM-MD-ph (r = -0.29) remained significant. A multivariate regression analysis including both brain tissues variables retained the GM volume (beta = -0.18, SE = 0.02, p < 0.001) and the GM average MD (beta = 45, SE = 19, p = 0.02) as independent predictors of subject's age. CONCLUSIONS: Brain white matter and gray matter have different vulnerabilities to aging. Microstructural imaging is important to achieve a complete picture of the complex changes occurring in the aging brain.


Subject(s)
Brain/anatomy & histology , Brain/growth & development , Magnetic Resonance Imaging/methods , Periaqueductal Gray/anatomy & histology , Periaqueductal Gray/growth & development , Adolescent , Adult , Aged , Aging , Child , Humans , Middle Aged , Reference Values , Reproducibility of Results
14.
Neurology ; 65(10): 1626-30, 2005 Nov 22.
Article in English | MEDLINE | ID: mdl-16301492

ABSTRACT

OBJECTIVE: To define the nature and the temporal evolution of neuronal/axonal injury in patients at the earliest clinical stage of multiple sclerosis (MS), using whole brain N-acetylaspartate (WBNAA) proton MR spectroscopy (1H-MRS). METHODS: Thirty-five patients at presentation with clinically isolated syndromes (CIS) and MRI evidence of disease dissemination in space were studied. The following scans of the brain were acquired within 3 months from the onset of the disease and after 12 months: 1) dual-echo; 2) WBNAA 1H-MRS; 3) pre- and postcontrast T1-weighted. The same scans were obtained in 12 age-matched healthy subjects, without contrast administration. In patients, conventional MRI scans were also repeated 3 months after the first scanning session, to assess the presence of early disease dissemination in time (DIT). RESULTS: Over the study period, 24 patients showed MRI evidence of disease DIT, thus fulfilling the criteria for a diagnosis of MS. The average WBNAA amount was lower in CIS patients than in controls both at baseline (13.7 vs 16.9 mM, p < 0.001) and at 1-year follow-up (12.6 vs 16.2 mM, p < 0.001), but the average yearly percentage change of WBNAA did not differ between the two groups. No MRI or 1H-MRS quantities were significantly associated with the disease DIT over the study period. CONCLUSION: Irreversible brain damage associated with axonal dysfunction occurs at a very early stage in patients with clinically isolated syndromes, but it does not seem to be related with the disease evolution in the subsequent short-term period.


Subject(s)
Axons/pathology , Central Nervous System/pathology , Multiple Sclerosis/diagnosis , Wallerian Degeneration/diagnosis , Adult , Central Nervous System/physiopathology , Diagnosis, Differential , Disease Progression , Early Diagnosis , Female , Humans , Magnetic Resonance Spectroscopy , Male , Multiple Sclerosis/physiopathology , Predictive Value of Tests , Prognosis , Wallerian Degeneration/etiology , Wallerian Degeneration/physiopathology
15.
Neurology ; 65(7): 1126-8, 2005 Oct 11.
Article in English | MEDLINE | ID: mdl-16217074

ABSTRACT

Little is known about the temporal evolution of gray matter damage occurring early in the course of multiple sclerosis (MS). The authors investigated the evolution of gray matter volume loss in 117 patients with relapsing-remitting MS, scanned monthly for a 9-month period. Time-trend analysis revealed a decrease of gray matter volumes over the study period (p < 0.001). This study shows that gray matter damage in relapsing-remitting MS evolves markedly over a short period of observation.


Subject(s)
Atrophy/diagnosis , Brain/pathology , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Adult , Atrophy/etiology , Atrophy/physiopathology , Brain/physiopathology , Cohort Studies , Disease Progression , Female , Humans , Longitudinal Studies , Magnetic Resonance Imaging , Male , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Nerve Degeneration/diagnosis , Nerve Degeneration/etiology , Nerve Degeneration/physiopathology , Nerve Fibers, Myelinated/pathology , Predictive Value of Tests
16.
Neurology ; 65(4): 633-5, 2005 Aug 23.
Article in English | MEDLINE | ID: mdl-16116134

ABSTRACT

The authors sought to identify clinical and MRI predictors of outcome in primary progressive multiple sclerosis (PPMS). Clinical and MRI assessments were performed at baseline and 2 and 5 years (clinical only). At baseline, disease duration, expanded disability status scale (EDSS) and brain volume predicted outcome. Adding short-term change variables, baseline EDSS, changes in T2* lesion load and cord area, and number of new lesions were predictive. Clinical and MRI variables predict long-term outcome in PPMS.


Subject(s)
Central Nervous System/pathology , Magnetic Resonance Imaging/statistics & numerical data , Multiple Sclerosis, Chronic Progressive/diagnosis , Multiple Sclerosis, Chronic Progressive/pathology , Atrophy/pathology , Brain/pathology , Brain/physiopathology , Central Nervous System/physiopathology , Cohort Studies , Data Collection , Diffusion Magnetic Resonance Imaging/standards , Disability Evaluation , Disease Progression , Humans , Longitudinal Studies , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/standards , Multiple Sclerosis, Chronic Progressive/physiopathology , Nerve Fibers, Myelinated/pathology , Neurologic Examination , Predictive Value of Tests , Prognosis , Prospective Studies , Spinal Cord/pathology , Spinal Cord/physiopathology , Time Factors
17.
Neuroimage ; 26(4): 1159-63, 2005 Jul 15.
Article in English | MEDLINE | ID: mdl-15878675

ABSTRACT

Brain damage in Alzheimer's disease (AD) and mild cognitive impairment (MCI) is widespread with involvement of large portions of the neocortex and the subcortical white matter. A quantitative measure of neuronal damage of the entire brain might be valuable in the context of large-scale, longitudinal studies of these patients. This study investigated the extent of neuroaxonal injury of patients with AD and MCI using a novel unlocalized proton magnetic resonance spectroscopy ((1)H-MRS) technique, which allows quantification of the concentration of N-acetylaspartate from the whole of the brain tissue (WBNAA). Conventional brain MRI and WBNAA were obtained from 28 AD patients, 27 MCI patients and 25 age-matched controls. Normalized brain volume (NBV) was also measured using an automated segmentation technique. WBNAA and NBV showed a significant heterogeneity between groups (P < 0.001). WBNAA concentration was different between controls and MCI patients (P = 0.003), but not between MCI and AD patients (P = 0.33). NBV differed both between controls and MCI patients (P = 0.02) and between MCI and AD patients (P = 0.03). A multivariate regression model retained WBNAA as the best MRI predictor of the Mini Mental State Examination score (P = 0.001). Significant neuronal damage, which is related to the extent of cognitive decline, can be quantified in the whole brain tissue of patients with AD, using a novel (1)H-MRS approach. The demonstration in patients with MCI of MR structural and metabolic findings, intermediate between those of healthy volunteers and those of AD patients, indicates that neuronal damage is already evident and widespread in individuals with MCI before they are clinically demented.


Subject(s)
Alzheimer Disease/pathology , Alzheimer Disease/psychology , Aspartic Acid/analogs & derivatives , Brain/pathology , Cognition Disorders/pathology , Cognition Disorders/psychology , Aged , Aspartic Acid/metabolism , Atrophy , Brain Chemistry , Female , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Male , Psychiatric Status Rating Scales , Reference Values
18.
Neurology ; 64(4): 631-5, 2005 Feb 22.
Article in English | MEDLINE | ID: mdl-15728283

ABSTRACT

OBJECTIVE: To investigate the extent and severity of cervical cord damage using diffusion tensor MRI (DT-MRI) and histogram analysis in patients with primary progressive MS (PPMS). METHODS: Diffusion-weighted sensitivity-encoded (SENSE) echoplanar images of the cervical cord and brain dual-echo and diffusion-weighted scans were acquired from 24 patients with PPMS and 13 healthy controls. Cord and brain mean diffusivity and fractional anisotropy histograms were produced. An analysis of variance model, adjusting for cord volume, was used to compare cord DT-MRI parameters from controls and patients. RESULTS: Compared to healthy controls, PPMS patients had reduced cervical cord cross-sectional area and average cord fractional anisotropy (p = 0.007), and increased cord mean diffusivity (p = 0.024). No correlations were found between DT-MRI metrics of the cord and quantities obtained from conventional and DT-MRI of the brain. CONCLUSIONS: DT-MRI of the cervical cord can quantify the extent of diffuse cord pathology in patients with PPMS. Such cord diffusivity changes in patients with PPMS are likely to reflect irreversible axonal injury and reactive gliosis and seem to be independent of brain damage.


Subject(s)
Diffusion Magnetic Resonance Imaging/methods , Multiple Sclerosis, Chronic Progressive/pathology , Spinal Cord/pathology , Adult , Aged , Anisotropy , Axons/pathology , Cervical Vertebrae , Diffusion , Female , Gliosis/etiology , Gliosis/pathology , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Multiple Sclerosis, Chronic Progressive/complications , Single-Blind Method
20.
Neurology ; 63(3): 584-5, 2004 Aug 10.
Article in English | MEDLINE | ID: mdl-15304603

ABSTRACT

Cervical cord magnetization transfer ratio (MTR) histograms were obtained from 45 patients at presentation with clinically isolated syndromes (CIS) suggestive of multiple sclerosis (MS). The mean values of MTR histogram-derived metrics were not different between CIS patients and healthy control subjects or between patients with and without evidence of disease dissemination in time. Only three patients showed significantly lower cord MTR values than control subjects. These findings suggest the absence of intrinsic structural damage of the cervical cord soon after the onset of CIS suggestive of MS, even in those patients with an early evolution to MS.


Subject(s)
Magnetic Resonance Imaging , Multiple Sclerosis/diagnosis , Spinal Cord/pathology , Adolescent , Adult , Brain Stem/pathology , Cerebral Cortex/pathology , Cervical Vertebrae , Disease Progression , Early Diagnosis , Female , Humans , Male , Middle Aged , Multiple Sclerosis/pathology , Optic Neuritis/etiology , Severity of Illness Index , Syndrome
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