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1.
Radiography (Lond) ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39266338

RESUMEN

INTRODUCTION: Many patients with atrial fibrillation have impaired renal function, and therefore pre-operative CT for radiofrequency catheter ablation should minimize the use of contrast media. This study describes a dual-region-of-interest (D-ROI) protocol for the scanning of pulmonary veins and left atrium (PVs-LA) with less contrast media and optimized scan timing compared to the single-region-of-interest (S-ROI) protocol, without compromising image quality. METHODS: This study retrospectively included 100 patients who underwent PVs-LA CT between July 2019 and February 2022. The participants were divided into two groups: Those scanned using the S-ROI method (Group A, n = 50), and those scanned using the D-ROI method (Group B, n = 50). Descriptive statistical analysis of the contrast effect and scan timing was performed using quantitative and qualitative data collected from both groups of images. RESULTS: The contrast media dose was larger in group A than in group B (63.6 ± 10.1 mL vs. 45.6 ± 6.9 mL; p < 0.001). The CT values of the PVs-LA did not differ significantly between groups A and B [434.2 ± 77.0 Hounsfield units (HU) and 428.8 ± 77.2 HU, respectively; p = 0.73]. Two evaluators determined appropriate scan timing (when PVs-LA reached a relatively sufficient contrast effect for diagnosis) in 23 (46%) and 45 (90%) patients from groups A and B, respectively (p < 0.001). CONCLUSIONS: Although the radiation dose is slightly increased compared with the S-ROI method, the D-ROI method provides improved scan timing and images with similar contrast enhancement while reducing the amount of contrast medium administered. IMPLICATIONS FOR PRACTICE: The novel D-ROI bolus tracking technique can reduce the contrast medium dose while optimizing scan timing.

2.
Rhinology ; 62(5): 557-565, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39026455

RESUMEN

BACKGROUND: Despite advances in techniques for olfactory neuroblastoma (ONB), such as unilateral cranial resection, preserving the patient’s sense of smell remains a challenge. This study aimed to examine the effectiveness of post-operative olfactory training in patients who underwent unilateral resection of ONB. METHODS: This retrospective cohort study assessed the effect of post-operative olfactory training on olfactory preservation in patients with ONB undergoing unilateral cranial resection. Patients were divided into training intervention (n = 5) and non-intervention (n = 6) groups. Olfactory tests were conducted pre-operatively and at multiple post-operative intervals. RESULTS: Partial olfactory function was preserved in all cases in the training intervention group, whereas only 17% of cases in the non-intervention group maintained partial olfactory function. Significant improvements in olfactory test scores were observed in the training intervention group compared with the non-intervention group. CONCLUSIONS: Our findings suggest that post-operative olfactory training could aid in olfactory preservation for patients with ONB after unilateral cranial resection. However, these results should be interpreted with caution, and further research with larger cohorts and extended follow-up periods is needed to confirm these observations.


Asunto(s)
Estesioneuroblastoma Olfatorio , Neoplasias Nasales , Trastornos del Olfato , Humanos , Estesioneuroblastoma Olfatorio/cirugía , Estudios Retrospectivos , Trastornos del Olfato/etiología , Masculino , Femenino , Neoplasias Nasales/cirugía , Persona de Mediana Edad , Adulto , Complicaciones Posoperatorias , Olfato/fisiología , Anciano
3.
Eur Phys J C Part Fields ; 83(9): 782, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37680254

RESUMEN

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7(16.3)×1020 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7×1020 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin2θ13 and the impact of priors on the δCP measurement. Both analyses prefer the normal mass ordering and upper octant of sin2θ23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin2θ13 from reactors, sin2θ23=0.561-0.032+0.021 using Feldman-Cousins corrected intervals, and Δm322=2.494-0.058+0.041×10-3eV2 using constant Δχ2 intervals. The CP-violating phase is constrained to δCP=-1.97-0.70+0.97 using Feldman-Cousins corrected intervals, and δCP=0,π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2σ credible level using a flat prior in δCP, and just below 2σ using a flat prior in sinδCP. When the external constraint on sin2θ13 is removed, sin2θ13=28.0-6.5+2.8×10-3, in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

4.
J Geophys Res Planets ; 127(9): e2022JE007231, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36583097

RESUMEN

We present water vapor vertical distributions on Mars retrieved from 3.5 years of solar occultation measurements by Nadir and Occultation for Mars Discovery onboard the ExoMars Trace Gas Orbiter, which reveal a strong contrast between aphelion and perihelion water climates. In equinox periods, most of water vapor is confined into the low-middle latitudes. In aphelion periods, water vapor sublimated from the northern polar cap is confined into very low altitudes-water vapor mixing ratios observed at the 0-5 km lower boundary of measurement decrease by an order of magnitude at the approximate altitudes of 15 and 30 km for the latitudes higher than 50°N and 30-50°N, respectively. The vertical confinement of water vapor at northern middle latitudes around aphelion is more pronounced in the morning terminators than evening, perhaps controlled by the diurnal cycle of cloud formation. Water vapor is also observed over the low latitude regions in the aphelion southern hemisphere (0-30°S) mostly below 10-20 km, which suggests north-south transport of water still occurs. In perihelion periods, water vapor sublimated from the southern polar cap directly reaches high altitudes (>80 km) over high southern latitudes, suggesting more effective transport by the meridional circulation without condensation. We show that heating during perihelion, sporadic global dust storms, and regional dust storms occurring annually around 330° of solar longitude (L S) are the main events to supply water vapor to the upper atmosphere above 70 km.

5.
AJNR Am J Neuroradiol ; 43(12): 1706-1712, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36396335

RESUMEN

BACKGROUND AND PURPOSE: Arterial stiffness is reported to be able to cause axonal demyelination or degeneration. The present study aimed to use advanced MR imaging techniques to examine the effect of arterial stiffness on the WM microstructure among older adults. MATERIALS AND METHODS: Arterial stiffness was measured using the cardio-ankle vascular elasticity index (CAVI). The high-CAVI (mean CAVI ≥ 9 points) and the low-CAVI groups (mean CAVI < 9 points) were created. The neuronal fiber integrity of the WM was evaluated by neurite orientation dispersion and density imaging and magnetization transfer saturation imaging. Tract-Based Spatial Statistics and the tracts-of-interest analysis were performed. Specific WM regions (corpus callosum, internal capsule, anterior thalamic radiation, corona radiata, superior longitudinal fasciculus, forceps minor, and inferior fronto-occipital fasciculus) were selected in the tracts-of-interest analysis. RESULTS: In Tract-Based Spatial Statistics, the high-CAVI group showed a significantly lower myelin volume fraction value in the broad WM and significantly higher radial diffusivity and isotropic volume fraction values in the corpus callosum, forceps minor, inferior fronto-occipital fasciculus, internal capsule, corona radiata, and anterior thalamic radiation than the low-CAVI group. In tracts-of-interest analysis using multivariate linear regression, significant associations were found between the mean CAVI and radial diffusivity in the anterior thalamic radiation and the corona radiata; isotropic volume fraction in the anterior thalamic radiation and the corona radiata; and myelin volume fraction in the superior longitudinal fasciculus (P < .05). Additionally, partial correlation coefficients were observed for the significant associations of executive function with radial diffusivity and myelin volume fraction (P < .05). CONCLUSIONS: Arterial stiffness could be associated with demyelination rather than axonal degeneration.


Asunto(s)
Enfermedades Desmielinizantes , Rigidez Vascular , Sustancia Blanca , Humanos , Anciano , Neuritas , Imagen de Difusión Tensora/métodos , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/diagnóstico por imagen , Encéfalo/diagnóstico por imagen
7.
Lett Appl Microbiol ; 74(4): 472-481, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34978719

RESUMEN

Emergence and rapid spread of multidrug-resistant (MDR) bacteria including Vibrio cholerae are a global public health issue. Much attention has been paid to natural compounds, such as spices and herbs to find novel antimicrobial compounds as they are considered to be cheaper alternatives to develop as a drug. Here, we show that methanol extract of white pepper could inhibit the growth of V. cholerae O1 El Tor variant, responsible for the recent outbreaks/epidemics. Furthermore, we demonstrate for the first time that piperine, the major component of white pepper, showed a dose-dependent bactericidal effect on V. cholerae growth irrespective of their biotypes and serogroups in the presence of 200 and 300 µg ml-1 of piperine, respectively. Piperine also inhibited the growth of MDR strains of Pseudomonas aeruginosa, Escherichia coli isolated from poultry and enterohemorrhagic/enteroaggregative E. coli O104 in the presence of 200 µg ml-1 . Interestingly, we did not observe any significant inhibitory effect of piperine on E. coli strains isolated from healthy person even up to 200 µg ml-1 . Our data suggest that piperine could be a novel antimicrobial agent in therapeutic and preventive applications against infections caused by pathogenic bacteria including MDR strains.


Asunto(s)
Cólera , Piper nigrum , Vibrio cholerae O1 , Vibrio cholerae , Alcaloides , Benzodioxoles , Cólera/microbiología , Escherichia coli , Variación Genética , Humanos , Piperidinas , Alcamidas Poliinsaturadas
8.
J Geophys Res Planets ; 127(10): e2022JE007203, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36589717

RESUMEN

To understand the evolving martian water cycle, a global perspective of the combined vertical and horizontal distribution of water is needed in relation to supersaturation and water loss and how it varies spatially and temporally. The global vertical water vapor distribution is investigated through an analysis that unifies water, temperature and dust retrievals from several instruments on multiple spacecraft throughout Mars Year (MY) 34 with a global circulation model. During the dusty season of MY 34, northern polar latitudes are largely absent of water vapor below 20 km with variations above this altitude due to transport from mid-latitudes during a global dust storm, the downwelling branch of circulation during perihelion season and the intense MY 34 southern summer regional dust storm. Evidence is found of supersaturated water vapor breaking into the northern winter polar vortex. Supersaturation above around 60 km is found for most of the time period, with lower altitudes showing more diurnal variation in the saturation state of the atmosphere. Discrete layers of supersaturated water are found across all latitudes. The global dust storm and southern summer regional dust storm forced water vapor at all latitudes in a supersaturated state to 60-90 km where it is more likely to escape from the atmosphere. The reanalysis data set provides a constrained global perspective of the water cycle in which to investigate the horizontal and vertical transport of water throughout the atmosphere, of critical importance to understand how water is exchanged between different reservoirs and escapes the atmosphere.

9.
AJNR Am J Neuroradiol ; 43(1): 48-55, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34794943

RESUMEN

BACKGROUND AND PURPOSE: Hypertension may be related to alterations of the glymphatic system, a waste metabolite drainage system in the brain. We aimed to investigate analysis along the perivascular space index changes in elderly subjects with hypertension. MATERIALS AND METHODS: Diffusion-weighted images were acquired from 126 subjects, including 63 subjects with hypertension (25 men and 38 women; mean age, 72.45 years) and 63 age- and sex-matched controls (25 men and 38 women; mean age, 72.16 years). We calculated the analysis along the perivascular space index as a ratio of the mean of x-axis diffusivities in the projection and association areas to the mean of y-axis diffusivity in the projection area and z-axis diffusivity in the association area. The left, right, and mean analysis along the perivascular space indices of both hemispheres were compared between the hypertension and control groups using a Mann-Whitney U test. The Spearman correlation coefficient was used to assess the correlation between the left, right, and mean ALPS indices and blood pressure and pulse pressure. RESULTS: The left (P = .011) and mean (P = .024) analysis along the perivascular space indices of the hypertension group were significantly lower than that of the control group. The left, right, and mean analysis along the perivascular space indices of all subjects were significantly negatively correlated with blood pressure values (r = -0.200 to -0.278, P = .002-0.046) and pulse pressure values (r = -0.221 to -0.245, P = .006-0.013). CONCLUSIONS: Our results are consistent with a model in which hypertension causes glymphatic dysfunction.


Asunto(s)
Sistema Glinfático , Hipertensión , Anciano , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora/métodos , Femenino , Sistema Glinfático/diagnóstico por imagen , Humanos , Hipertensión/complicaciones , Masculino , Agua
10.
Sci Data ; 8(1): 218, 2021 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-34385471

RESUMEN

The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâ†’vτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.

11.
AJNR Am J Neuroradiol ; 42(3): 471-478, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33414234

RESUMEN

BACKGROUND AND PURPOSE: Synthetic MR imaging creates multiple contrast-weighted images based on a single time-efficient quantitative scan, which has been mostly performed for 2D acquisition. We assessed the utility of 3D synthetic MR imaging in patients with MS by comparing its diagnostic image quality and lesion volumetry with conventional MR imaging. MATERIALS AND METHODS: Twenty-four patients with MS prospectively underwent 3D quantitative synthetic MR imaging and conventional T1-weighted, T2-weighted, FLAIR, and double inversion recovery imaging, with acquisition times of 9 minutes 3 seconds and 18 minutes 27 seconds for the synthetic MR imaging and conventional MR imaging sequences, respectively. Synthetic phase-sensitive inversion recovery images and those corresponding to conventional MR imaging contrasts were created for synthetic MR imaging. Two neuroradiologists independently assessed the image quality on a 5-point Likert scale. The numbers of cortical lesions and lesion volumes were quantified using both synthetic and conventional image sets. RESULTS: The overall diagnostic image quality of synthetic T1WI and double inversion recovery images was noninferior to that of conventional images (P = .23 and .20, respectively), whereas that of synthetic T2WI and FLAIR was inferior to that of conventional images (both Ps < .001). There were no significant differences in the number of cortical lesions (P = .17 and .53 for each rater) or segmented lesion volumes (P = .61) between the synthetic and conventional image sets. CONCLUSIONS: Three-dimensional synthetic MR imaging could serve as an alternative to conventional MR imaging in evaluating MS with a reduced scan time.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple/diagnóstico por imagen , Adulto , Encéfalo/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/patología
13.
Sci Rep ; 10(1): 14415, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32934273

RESUMEN

The Antarctic continental margin supplies the densest bottom water to the global abyss. From the late twentieth century, an acceleration in the long-term freshening of Antarctic Bottom Waters (AABW) has been detected in the Australian-Antarctic Basin. Our latest hydrographic observations reveal that, in the late 2010s, the freshening trend has reversed broadly over the continental slope. Near-bottom salinities in 2018-2019 were higher than during 2011-2015. Along 170° E, the salinity increase between 2011 and 2018 was greater than that observed in the west. The layer thickness of the densest AABW increased during the 2010s, suggesting that the Ross Sea Bottom Water intensification was a major source of the salinity increase. Freshwater content on the continental slope decreased at a rate of 58 ± 37 Gt/a in the near-bottom layer. The decadal change is very likely due to changes in Ross Sea shelf water attributable to a decrease in meltwater from West Antarctic ice shelves for the corresponding period.

14.
AJNR Am J Neuroradiol ; 41(9): 1618-1624, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32855183

RESUMEN

BACKGROUND AND PURPOSE: Although chronic ischemia is known to induce myelin and axonal damage in animal models, knowledge regarding patients with Moyamoya disease is limited. We aimed to investigate the presence of myelin and axonal damage in Moyamoya disease and their relationship with cognitive performance. MATERIALS AND METHODS: Eighteen patients with Moyamoya disease (16-55 years of age) and 18 age- and sex-matched healthy controls were evaluated with myelin-sensitive MR imaging based on magnetization transfer saturation imaging and 2-shell diffusion MR imaging. The myelin volume fraction, which reflects the amount of myelin sheath; the g-ratio, which represents the ratio of the inner (axon) to the outer (axon plus myelin) diameter of the fiber; and the axon volume fraction, which reflects axonal components, were calculated and compared between the patients and controls. In the patients with Moyamoya disease, the relationship between these parameters and cognitive task-measuring performance speed was also evaluated. RESULTS: Compared with the healthy controls, the patients with Moyamoya disease showed a significant decrease in the myelin and axon volume fractions (P < .05) in many WM regions, while the increases in the g-ratio values were not statistically significant. Correlations with cognitive performance were most frequently observed with the axon volume fraction (r = 0.52-0.54; P < .03 in the right middle and posterior cerebral artery areas) and were the strongest with the g-ratio values in the right posterior cerebral artery region (r = 0.64; P = .004). CONCLUSIONS: Myelin-sensitive MR imaging and diffusion MR imaging revealed that myelin and axonal damage exist in patients with Moyamoya disease. The relationship with cognitive performance might be stronger with axonal damage than with myelin damage.


Asunto(s)
Axones/patología , Encéfalo/patología , Enfermedad de Moyamoya/patología , Vaina de Mielina/patología , Sustancia Blanca/patología , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Moyamoya/diagnóstico por imagen , Neuroimagen/métodos , Sustancia Blanca/diagnóstico por imagen , Adulto Joven
15.
Phys Rev Lett ; 124(16): 161802, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-32383902

RESUMEN

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

17.
Clin Exp Immunol ; 200(3): 302-309, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32155293

RESUMEN

Stroke can be a cause of death, while in non-fatal cases it is a common cause of various disabilities resulting from associated brain damage. However, whether a specific periodontal pathogen is associated with increased risk of unfavorable outcome after stroke remains unknown. We examined risk factors for unfavorable outcome following stroke occurrence, including serum antibody titers to periodontal pathogens. The enrolled cohort included 534 patients who had experienced an acute stroke, who were divided into favorable (n = 337) and unfavorable (n = 197) outcome groups according to modified ranking scale (mRS) score determined at 3 months after onset (favorable = score 0 or 1; unfavorable = score 2-6). The associations of risk factors with unfavorable outcome, including serum titers of IgG antibodies to 16 periodontal pathogens, were examined. Logistic regression analysis showed that the initial National Institutes of Health stroke scale score [odds ratio (OR) = 1·24, 95% confidence interval (CI) = 1·18-1·31, P < 0·001] and C-reactive protein (OR = 1·29, 95% CI = 1·10-1·51, P = 0·002) were independently associated with unfavorable outcome after stroke. Following adjustment with those, detection of the antibody for Fusobacterium nucleatum ATCC 10953 in serum remained an independent predictor of unfavorable outcome (OR = 3·12, 95% CI = 1·55-6·29, P = 0·002). Determination of the antibody titer to F. nucleatum ATCC 10953 in serum may be useful as a predictor of unfavorable outcome after stroke.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Fusobacterium nucleatum/metabolismo , Inmunoglobulina G/sangre , Accidente Cerebrovascular/sangre , Anciano , Anciano de 80 o más Años , Anticuerpos Antibacterianos/inmunología , Femenino , Fusobacterium nucleatum/inmunología , Humanos , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Riesgo , Accidente Cerebrovascular/inmunología
19.
AJNR Am J Neuroradiol ; 40(11): 1894-1900, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31601573

RESUMEN

BACKGROUND AND PURPOSE: CBF analysis of DSC perfusion using the singular value decomposition algorithm is not accurate in patients with Moyamoya disease. This study compared the Bayesian estimation of CBF against the criterion standard PET and singular value decomposition methods in patients with Moyamoya disease. MATERIALS AND METHODS: Nineteen patients with Moyamoya disease (10 women; 22-52 years of age) were evaluated with both DSC and 15O-gas PET within 60 days. DSC-CBF maps were created using Bayesian analysis and 3 singular value decomposition analyses (standard singular value decomposition, a block-circulant deconvolution method with a fixed noise cutoff, and a block-circulant deconvolution method that adopts an occillating noise cutoff for each voxel according to the strength of noise). Qualitative and quantitative analyses of the Bayesian-CBF and singular value decomposition-CBF methods were performed against 15O-gas PET and compared with each other. RESULTS: In qualitative assessments of DSC-CBF maps, Bayesian-CBF maps showed better visualization of decreased CBF on PET (sensitivity = 62.5%, specificity = 100%, positive predictive value = 100%, negative predictive value = 78.6%) than a block-circulant deconvolution method with a fixed noise cutoff and a block-circulant deconvolution method that adopts an oscillating noise cutoff for each voxel according to the strength of noise (P < .03 for all except for specificity). Quantitative analysis of CBF showed that the correlation between Bayesian-CBF and PET-CBF values (ρ = 0.46, P < .001) was similar among the 3 singular value decomposition methods, and Bayesian analysis overestimated true CBF (mean difference, 47.28 mL/min/100 g). However, the correlation between CBF values normalized to the cerebellum was better in Bayesian analysis (ρ = 0.56, P < .001) than in the 3 singular value decomposition methods (P < .02). CONCLUSIONS: Compared with previously reported singular value decomposition algorithms, Bayesian analysis of DSC perfusion enabled better qualitative and quantitative assessments of CBF in patients with Moyamoya disease.


Asunto(s)
Encéfalo/diagnóstico por imagen , Circulación Cerebrovascular/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Enfermedad de Moyamoya/diagnóstico por imagen , Neuroimagen/métodos , Adulto , Algoritmos , Teorema de Bayes , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Enfermedad de Moyamoya/fisiopatología , Imagen de Perfusión/métodos , Tomografía de Emisión de Positrones/métodos , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
20.
AJNR Am J Neuroradiol ; 40(10): 1642-1648, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31515218

RESUMEN

BACKGROUND AND PURPOSE: A number of MR-derived quantitative metrics have been suggested to assess the pathophysiology of MS, but the reports about combined analyses of these metrics are scarce. Our aim was to assess the spatial distribution of parameters for white matter myelin and axon integrity in patients with relapsing-remitting MS by multiparametric MR imaging. MATERIALS AND METHODS: Twenty-four patients with relapsing-remitting MS and 24 age- and sex-matched controls were prospectively scanned by quantitative synthetic and 2-shell diffusion MR imaging. Synthetic MR imaging data were used to retrieve relaxometry parameters (R1 and R2 relaxation rates and proton density) and myelin volume fraction. Diffusion tensor metrics (fractional anisotropy and mean, axial, and radial diffusivity) and neurite orientation and dispersion index metrics (intracellular volume fraction, isotropic volume fraction, and orientation dispersion index) were retrieved from diffusion MR imaging data. These data were analyzed using Tract-Based Spatial Statistics. RESULTS: Patients with MS showed significantly lower fractional anisotropy and myelin volume fraction and higher isotropic volume fraction in widespread white matter areas. Areas with different isotropic volume fractions were included within areas with lower fractional anisotropy. Myelin volume fraction showed no significant difference in some areas with significantly decreased fractional anisotropy in MS, including in the genu of the corpus callosum and bilateral anterior corona radiata, whereas myelin volume fraction was significantly decreased in some areas where fractional anisotropy showed no significant difference, including the bilateral posterior limb of the internal capsule, external capsule, sagittal striatum, fornix, and uncinate fasciculus. CONCLUSIONS: We found differences in spatial distribution of abnormality in fractional anisotropy, isotropic volume fraction, and myelin volume fraction distribution in MS, which might be useful for characterizing white matter in patients with MS.


Asunto(s)
Imagen de Difusión Tensora/métodos , Imagen por Resonancia Magnética/métodos , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple/diagnóstico por imagen , Neuritas , Neuroimagen/métodos , Sustancia Blanca/diagnóstico por imagen , Adulto , Anisotropía , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Vaina de Mielina , Estudios Prospectivos
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