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1.
Martin Ott Martin Blaimer Felix Breuer David Grodzki Björn Heismann Peter Jakob 《Magma (New York, N.Y.)》2016,29(1):5-15
Objective
To reduce acoustic noise levels in T 1-weighted and proton-density-weighted turbo spin-echo (TSE) sequences, which typically reach acoustic noise levels up to 100 dB(A) in clinical practice.Materials and methods
Five acoustic noise reduction strategies were combined: (1) gradient ramps and shapes were changed from trapezoidal to triangular, (2) variable-encoding-time imaging was implemented to relax the phase-encoding gradient timing, (3) RF pulses were adapted to avoid the need for reversing the polarity of the slice-rewinding gradient, (4) readout bandwidth was increased to provide more time for gradient activity on other axes, (5) the number of slices per TR was reduced to limit the total gradient activity per unit time. We evaluated the influence of each measure on the acoustic noise level, and conducted in vivo measurements on a healthy volunteer. Sound recordings were taken for comparison.Results
An overall acoustic noise reduction of up to 16.8 dB(A) was obtained by the proposed strategies (1–4) and the acquisition of half the number of slices per TR only. Image quality in terms of SNR and CNR was found to be preserved.Conclusions
The proposed measures in this study allowed a threefold reduction in the acoustic perception of T 1-weighted and proton-density-weighted TSE sequences compared to a standard TSE-acquisition. This could be achieved without visible degradation of image quality, showing the potential to improve patient comfort and scan acceptability.2.
Jorge Zavala Bojorquez Stéphanie Bricq François Brunotte Paul M. Walker Alain Lalande 《Magma (New York, N.Y.)》2016,29(5):777-788
Objective
To segment and classify the different attenuation regions from MRI at the pelvis level using the T 1 and T 2 relaxation times and anatomical knowledge as a first step towards the creation of PET/MR attenuation maps.Materials and methods
Relaxation times were calculated by fitting the pixel-wise intensities of acquired T 1- and T 2-weighted images from eight men with inversion-recovery and multi-echo multi-slice spin-echo sequences. A decision binary tree based on relaxation times was implemented to segment and classify fat, muscle, prostate, and air (within the body). Connected component analysis and an anatomical knowledge-based procedure were implemented to localize the background and bone.Results
Relaxation times at 3 T are reported for fat (T 1 = 385 ms, T 2 = 121 ms), muscle (T 1 = 1295 ms, T 2 = 40 ms), and prostate (T 1 = 1700 ms, T 2 = 80 ms). The relaxation times allowed the segmentation–classification of fat, prostate, muscle, and air, and combined with anatomical knowledge, they allowed classification of bone. The good segmentation–classification of prostate [mean Dice similarity score (mDSC) = 0.70] suggests a viable implementation in oncology and that of fat (mDSC = 0.99), muscle (mDSC = 0.99), and bone (mDSCs = 0.78) advocates for its implementation in PET/MR attenuation correction.Conclusion
Our method allows the segmentation and classification of the attenuation-relevant structures required for the generation of the attenuation map of PET/MR systems in prostate imaging: air, background, bone, fat, muscle, and prostate.3.
Vassilios S. Vassiliou Katharina Wassilew Donnie Cameron Ee Ling Heng Evangelia Nyktari George Asimakopoulos Anthony de Souza Shivraman Giri Iain Pierce Andrew Jabbour David Firmin Michael Frenneaux Peter Gatehouse Dudley J. Pennell Sanjay K. Prasad 《Magma (New York, N.Y.)》2018,31(1):101-113
Objectives
Our objectives involved identifying whether repeated averaging in basal and mid left ventricular myocardial levels improves precision and correlation with collagen volume fraction for 11 heartbeat MOLLI T 1 mapping versus assessment at a single ventricular level.Materials and methods
For assessment of T 1 mapping precision, a cohort of 15 healthy volunteers underwent two CMR scans on separate days using an 11 heartbeat MOLLI with a 5(3)3 beat scheme to measure native T 1 and a 4(1)3(1)2 beat post-contrast scheme to measure post-contrast T 1, allowing calculation of partition coefficient and ECV. To assess correlation of T 1 mapping with collagen volume fraction, a separate cohort of ten aortic stenosis patients scheduled to undergo surgery underwent one CMR scan with this 11 heartbeat MOLLI scheme, followed by intraoperative tru-cut myocardial biopsy. Six models of myocardial diffuse fibrosis assessment were established with incremental inclusion of imaging by averaging of the basal and mid-myocardial left ventricular levels, and each model was assessed for precision and correlation with collagen volume fraction.Results
A model using 11 heart beat MOLLI imaging of two basal and two mid ventricular level averaged T 1 maps provided improved precision (Intraclass correlation 0.93 vs 0.84) and correlation with histology (R 2 = 0.83 vs 0.36) for diffuse fibrosis compared to a single mid-ventricular level alone. ECV was more precise and correlated better than native T 1 mapping.Conclusion
T 1 mapping sequences with repeated averaging could be considered for applications of 11 heartbeat MOLLI, especially when small changes in native T 1/ECV might affect clinical management.4.
Fabian Zimmer Kieran O’Brien Steffen Bollmann Josef Pfeuffer Keith Heberlein Markus Barth 《Magma (New York, N.Y.)》2016,29(3):463-473
Objective
Arterial spin labelling (ASL) techniques benefit from the increased signal-to-noise ratio and the longer T 1 relaxation times available at ultra-high field. Previous pulsed ASL studies at 7 T concentrated on the superior regions of the brain because of the larger transmit radiofrequency inhomogeneity experienced at ultra-high field that hinders an adequate inversion of the blood bolus when labelling in the neck. Recently, researchers have proposed to overcome this problem with either the use of dielectric pads, through dedicated transmit labelling coils, or special adiabatic inversion pulses.Materials and methods
We investigate the performance of an optimised time-resampled frequency-offset corrected inversion (TR-FOCI) pulse designed to cause inversion at much lower peak B 1 + . In combination with a PICORE labelling, the perfusion signal obtained with this pulse is compared against that obtained with a FOCI pulse, with and without dielectric pads.Results
Mean grey matter perfusion with the TR-FOCI was 52.5 ± 10.3 mL/100 g/min, being significantly higher than the 34.6 ± 2.6 mL/100 g/min obtained with the FOCI pulse. No significant effect of the dielectric pads was observed.Conclusion
The usage of the B 1 + -optimised TR-FOCI pulse results in a significantly higher perfusion signal. PICORE–ASL is feasible at ultra-high field with no changes to operating conditions.5.
Harue Kubota Denis A. Komarov Hironobu Yasui Shingo Matsumoto Osamu Inanami Igor A. Kirilyuk Valery V. Khramtsov Hiroshi Hirata 《Magma (New York, N.Y.)》2017,30(3):291-298
Objectives
The aim of this study was to demonstrate the feasibility of in vivo three-dimensional (3D) relaxation time T 2 * mapping of a dicarboxy-PROXYL radical using continuous-wave electron paramagnetic resonance (CW-EPR) imaging.Materials and methods
Isotopically substituted dicarboxy-PROXYL radicals, 3,4-dicarboxy-2,2,5,5-tetra(2H3)methylpyrrolidin-(3,4-2H2)-(1-15N)-1-oxyl (2H,15N-DCP) and 3,4-dicarboxy-2,2,5,5-tetra(2H3)methylpyrrolidin-(3,4-2H2)-1-oxyl (2H-DCP), were used in the study. A clonogenic cell survival assay was performed with the 2H-DCP radical using squamous cell carcinoma (SCC VII) cells. The time course of EPR signal intensities of intravenously injected 2H,15N-DCP and 2H-DCP radicals were determined in tumor-bearing hind legs of mice (C3H/HeJ, male, n = 5). CW-EPR-based single-point imaging (SPI) was performed for 3D T 2 * mapping.Results
2H-DCP radical did not exhibit cytotoxicity at concentrations below 10 mM. The in vivo half-life of 2H,15N-DCP in tumor tissues was 24.7 ± 2.9 min (mean ± standard deviation [SD], n = 5). The in vivo time course of the EPR signal intensity of the 2H,15N-DCP radical showed a plateau of 10.2 ± 1.2 min (mean ± SD) where the EPR signal intensity remained at more than 90% of the maximum intensity. During the plateau, in vivo 3D T 2 * maps with 2H,15N-DCP were obtained from tumor-bearing hind legs, with a total acquisition time of 7.5 min.Conclusion
EPR signals of 2H,15N-DCP persisted long enough after bolus intravenous injection to conduct in vivo 3D T 2 * mapping with CW-EPR-based SPI.6.
Objective
Recent MRI studies have shown that the orientation of nerve fibres relative to the main magnetic field affects the R2*(= 1/T2*) relaxation rate in white matter (WM) structures. The underlying physical causes have been discussed in several studies but are still not completely understood. However, understanding these effects in detail is of great importance since this might serve as a basis for the development of new diagnostic tools and/or improve quantitative susceptibility mapping techniques. Therefore, in addition to the known angular dependence of R2*, the current study investigates the relationship between fibre orientation and the longitudinal relaxation rate, R1 (= 1/T1), as well as the apparent water content.Materials and methods
For a group of 16 healthy subjects, a series of gradient echo, echo-planar and diffusion weighted images were acquired at 3T from which the decay rates, the apparent water content and the diffusion direction were reconstructed. The diffusion weighted data were used to determine the angle between the principle fibre direction and the main magnetic field to examine the angular dependence of R1 and apparent water content.Results
The obtained results demonstrate that both parameters depend on the fibre orientation and exhibit a positive correlation with the angle between fibre direction and main magnetic field.Conclusion
These observations could be helpful to improve and/or constrain existing biophysical models of brain microstructure by imposing additional constraints resulting from the observed angular dependence R1 and apparent water content in white matter.7.
Michael J. Knight Bryony McCann Demitra Tsivos Elizabeth Couthard Risto A. Kauppinen 《Magma (New York, N.Y.)》2016,29(6):833-842
Objective
The objective of this study was to examine age-dependent changes in both T1-weighted and T2-weighted image contrasts and spin-echo T2 relaxation time in the human brain during healthy ageing.Methods
A total of 37 participants between the ages of 49 and 87 years old were scanned with a 3 Tesla system, using T1-weighted, T2 weighted and quantitative spin-echo T2 imaging. Contrast between image intensities and T2 values was calculated for various regions, including between individual hippocampal subfields.Results
The T1 contrast-to-noise (CNR) and gray:white signal intensity ratio (GWR) did not change in the hippocampus, but it declined in the cingulate cortex with age. In contrast, T2 CNR and GWR declined in both brain regions. T2 relaxation time was almost constant in gray matter and most (but not all) hippocampal subfields, but increased substantially in white matter, pointing to an age effect on water relaxation in white matter.Conclusions
Changes in T1 and T2 MR characteristics influence the appearance of brain images in later life and should be considered in image analyses of aged subjects. It is speculated that alterations at the cell biology level, with concomitant alterations to the local magnetic environment, reduce dephasing and subsequently prolong spin-echo T2 through reduced diffusion effects in later life.8.
Uten Yarach Chaiya Luengviriya Daniel Stucht Frank Godenschweger Peter Schulze Oliver Speck 《Magma (New York, N.Y.)》2016,29(3):319-332
Objective
Prospective motion correction can effectively fix the imaging volume of interest. For large motion, this can lead to relative motion of coil sensitivities, distortions associated with imaging gradients and B 0 field variations. This work accounts for the B 0 field change due to subject movement, and proposes a method for correcting tissue magnetic susceptibility-related distortion in prospective motion correction.Materials and methods
The B 0 field shifts at the different head orientations were characterized. A volunteer performed large motion with prospective motion correction enabled. The acquired data were divided into multiple groups according to the object positions. The correction of B 0-related distortion was applied to each group of data individually via augmented sensitivity encoding with additionally integrated gradient nonlinearity correction.Results
The relative motion of the gradients, B 0 field and coil sensitivities in prospective motion correction results in residual spatial distortion, blurring, and coil artifacts. These errors can be mitigated by the proposed method. Moreover, iterative conjugate gradient optimization with regularization provided superior results with smaller RMSE in comparison to standard conjugate gradient.Conclusion
The combined correction of B 0-related distortion and gradient nonlinearity leads to a reduction of residual motion artifacts in prospective motion correction data.9.
Objective
Purely phase-encoded techniques such as single point imaging (SPI) are generally unsuitable for in vivo imaging due to lengthy acquisition times. Reconstruction of highly undersampled data using compressed sensing allows SPI data to be quickly obtained from animal models, enabling applications in preclinical cellular and molecular imaging.Materials and methods
TurboSPI is a multi-echo single point technique that acquires hundreds of images with microsecond spacing, enabling high temporal resolution relaxometry of large-R 2* systems such as iron-loaded cells. TurboSPI acquisitions can be pseudo-randomly undersampled in all three dimensions to increase artifact incoherence, and can provide prior information to improve reconstruction. We evaluated the performance of CS-TurboSPI in phantoms, a rat ex vivo, and a mouse in vivo.Results
An algorithm for iterative reconstruction of TurboSPI relaxometry time courses does not affect image quality or R 2* mapping in vitro at acceleration factors up to 10. Imaging ex vivo is possible at similar acceleration factors, and in vivo imaging is demonstrated at an acceleration factor of 8, such that acquisition time is under 1 h.Conclusions
Accelerated TurboSPI enables preclinical R 2* mapping without loss of data quality, and may show increased specificity to iron oxide compared to other sequences.10.
11.
Objective
Intravoxel incoherent motion (IVIM) shows great potential in many applications, e.g., tumor tissue characterization. To reduce image-quality demands, various IVIM analysis approaches restricted to the diffusion coefficient (D) and the perfusion fraction (f) are increasingly being employed. In this work, the impact of estimation approach for D and f is studied.Materials and methods
Four approaches for estimating D and f were studied: segmented IVIM fitting, least-squares fitting of a simplified IVIM model (sIVIM), and Bayesian fitting of the sIVIM model using marginal posterior modes or posterior means. The estimation approaches were evaluated in terms of bias and variability as well as ability for differentiation between tumor and healthy liver tissue using simulated and in vivo data.Results
All estimation approaches had similar variability and ability for differentiation and negligible bias, except for the Bayesian posterior mean of f, which was substantially biased. Combined use of D and f improved tumor-to-liver tissue differentiation compared with using D or f separately.Discussion
The similar performance between estimation approaches renders the segmented one preferable due to lower numerical complexity and shorter computational time. Superior tissue differentiation when combining D and f suggests complementary biologically relevant information.12.
Silvin Paul Knight Jacinta Elizabeth Browne James Frances Mary Meaney Andrew John Fagan 《Magma (New York, N.Y.)》2017,30(5):461-471
Objectives
The aim of this study was to investigate the effect of the temporal resolution (T res) and acquisition duration (AD) on the measurement accuracy of contrast concentration–time curves (CTCs), and derived phenomenological and pharmacokinetic parameter values, in a dynamic contrast-enhanced MRI experiment using a novel phantom test device.Materials and methods
‘Ground truth’ CTCs were established using a highly precise optical imaging system. These precisely known CTCs were produced in an anthropomorphic environment, which mimicked the male pelvic region, and presented to the MRI scanner for measurement. The T res was varied in the range [2–24.4 s] and the AD in the range [30–600 s], and the effects on the measurement accuracy were quantified.Results
For wash-in parameter measurements, large underestimation errors (up to 40%) were found using T res values ≥16.3 s; however, the measured wash-out rate did not vary greatly across all T res values tested. Errors in derived K trans and v e values were below 14 and 12% for acquisitions with {T res ≤ 8.1 s, AD ≥ 360 s} and {T res ≤ 16.3 s, AD ≥ 360 s}, respectively, but increased dramatically outside these ranges.Conclusions
Errors in measured wash-in, wash-out, K trans, and v e parameters were minimised using T res ≤ 8.1 s and AD ≥ 360 s, with large errors recorded outside of this range.13.
Maria Filomena Santarelli Antonella Meloni Daniele De Marchi Laura Pistoia Antonella Quarta Anna Spasiano Luigi Landini Alessia Pepe Vincenzo Positano 《Magma (New York, N.Y.)》2018,31(6):757-769
Objectives
To propose a method for estimating pancreatic relaxation rate, R2*, from conventional multi-echo MRI, based on the nonlinear fitting of the acquired magnitude signal decay to MR signal models that take into account both the signal oscillations induced by fat and the different R2* values of pancreatic parenchyma and fat.Materials and methods
Single-peak fat (SPF) and multi-peak fat (MPF) models were introduced. Single-R2* and dual-R2* assumptions were considered as well. Analyses were conducted on simulated data and 20 thalassemia major patients.Results
Simulations revealed the ability of the MPF model to correctly estimate the R2* value in a large range of fat fractions and R2* values. From the comparison between the results obtained with a single R2* value for water and fat and the dual-R2* approach, the latter is more accurate in both water R2* and fat fraction estimation. In patient’s data analysis, a strong concordance was found between SPF and MPF estimated data with measurements done with manual signal correction and from fat-saturated images. The MPF method showed better reproducibility.Conclusion
The MPF dual-R2* approach improves reproducibility and reduces image analysis time in the assessment of pancreatic R2* value in patients with iron overload.14.
Guido H. Jajamovich Wei Huang Cecilia Besa Xin Li Aneela Afzal Hadrien A. Dyvorne Bachir Taouli 《Magma (New York, N.Y.)》2016,29(1):49-58
Objective
To quantify hepatocellular carcinoma (HCC) perfusion and flow with the fast exchange regime-allowed Shutter-Speed model (SSM) compared to the Tofts model (TM).Materials and methods
In this prospective study, 25 patients with HCC underwent DCE-MRI. ROIs were placed in liver parenchyma, portal vein, aorta and HCC lesions. Signal intensities were analyzed employing dual-input TM and SSM models. ART (arterial fraction), K trans (contrast agent transfer rate constant from plasma to extravascular extracellular space), v e (extravascular extracellular volume fraction), k ep (contrast agent intravasation rate constant), and τ i (mean intracellular water molecule lifetime) were compared between liver parenchyma and HCC, and ART, K trans, v e and k ep were compared between models using Wilcoxon tests and limits of agreement. Test–retest reproducibility was assessed in 10 patients.Results
ART and v e obtained with TM; ART, v e , k e and τ i obtained with SSM were significantly different between liver parenchyma and HCC (p < 0.04). Parameters showed variable reproducibility (CV range 14.7–66.5 % for both models). Liver K trans and v e ; HCC v e and k ep were significantly different when estimated with the two models (p < 0.03).Conclusion
Our results show differences when computed between the TM and the SSM. However, these differences are smaller than parameter reproducibilities and may be of limited clinical significance.15.
Manoj Shrestha Toralf Mildner Torsten Schlumm Scott Haile Robertson Harald Möller 《Magma (New York, N.Y.)》2016,29(6):799-810
Objective
Echo-planar imaging (EPI) with CYlindrical Center-out spatiaL Encoding (EPICYCLE) is introduced as a novel hybrid three-dimensional (3D) EPI technique. Its suitability for the tracking of a short bolus created by pseudo-continuous arterial spin labeling (pCASL) through the cerebral vasculature is demonstrated.Materials and methods
EPICYCLE acquires two-dimensional planes of k-space along center-out trajectories. These “spokes” are rotated from shot to shot about a common axis to encode a k-space cylinder. To track a bolus of labeled blood, the same subset of evenly distributed spokes is acquired in a cine fashion after a short period of pCASL. This process is repeated for all subsets to fill the whole 3D k-space of each time frame.Results
The passage of short pCASL boluses through the vasculature of a 3D imaging slab was successfully imaged using EPICYCLE. By choosing suitable sequence parameters, the impact of slab excitation on the bolus shape could be minimized. Parametric maps of signal amplitude, transit time, and bolus width reflected typical features of blood transport in large vessels.Conclusion
The EPICYCLE technique was successfully applied to track a short bolus of labeled arterial blood during its passage through the cerebral vasculature.16.
Jianmin Yuan Ammara Usman Scott A. Reid Kevin F. King Andrew J. Patterson Jonathan H. Gillard Martin J. Graves 《Magma (New York, N.Y.)》2018,31(1):183-190
Objective
The purpose of this work is to evaluate the repeatability of a compressed sensing (CS) accelerated multi-contrast carotid protocol at 3 T.Materials and methods
Twelve volunteers and eight patients with carotid disease were scanned on a 3 T MRI scanner using a CS accelerated 3-D black-blood multi-contrast protocol which comprises T 1w, T 2w and PDw without CS, and with a CS factor of 1.5 and 2.0. The volunteers were scanned twice, the lumen/wall area and wall thickness were measured for each scan. Eight patients were scanned once, the inter/intra-observer reproducibility of the measurements was calculated.Results
In the repeated volunteer scans, the interclass correlation coefficient (ICC) for the wall area measurement using a CS factor of 1.5 in PDw, T 1w and T 2w were 0.95, 0.81, and 0.97, respectively. The ICC for lumen area measurement using a CS factor of 1.5 in PDw, T 1w and T 2w were 0.96, 0.92, and 0.96, respectively. In patients, the ICC for inter/intra-observer measurements of lumen/wall area, and wall thickness were all above 0.81 in all sequences.Conclusion
The results show a CS accelerated 3-D black-blood multi-contrast protocol is a robust and reproducible method for carotid imaging. Future protocol design could use CS to reduce the scanning time.17.
Faezeh Fallah Jürgen Machann Petros Martirosian Fabian Bamberg Fritz Schick Bin Yang 《Magma (New York, N.Y.)》2017,30(2):139-151
Objectives
To evaluate and compare conventional T1-weighted 2D turbo spin echo (TSE), T1-weighted 3D volumetric interpolated breath-hold examination (VIBE), and two-point 3D Dixon-VIBE sequences for automatic segmentation of visceral adipose tissue (VAT) volume at 3 Tesla by measuring and compensating for errors arising from intensity nonuniformity (INU) and partial volume effects (PVE).Materials and methods
The body trunks of 28 volunteers with body mass index values ranging from 18 to 41.2 kg/m2 (30.02 ± 6.63 kg/m2) were scanned at 3 Tesla using three imaging techniques. Automatic methods were applied to reduce INU and PVE and to segment VAT. The automatically segmented VAT volumes obtained from all acquisitions were then statistically and objectively evaluated against the manually segmented (reference) VAT volumes.Results
Comparing the reference volumes with the VAT volumes automatically segmented over the uncorrected images showed that INU led to an average relative volume difference of ?59.22 ± 11.59, 2.21 ± 47.04, and ?43.05 ± 5.01 % for the TSE, VIBE, and Dixon images, respectively, while PVE led to average differences of ?34.85 ± 19.85, ?15.13 ± 11.04, and ?33.79 ± 20.38 %. After signal correction, differences of ?2.72 ± 6.60, 34.02 ± 36.99, and ?2.23 ± 7.58 % were obtained between the reference and the automatically segmented volumes. A paired-sample two-tailed t test revealed no significant difference between the reference and automatically segmented VAT volumes of the corrected TSE (p = 0.614) and Dixon (p = 0.969) images, but showed a significant VAT overestimation using the corrected VIBE images.Conclusion
Under similar imaging conditions and spatial resolution, automatically segmented VAT volumes obtained from the corrected TSE and Dixon images agreed with each other and with the reference volumes. These results demonstrate the efficacy of the signal correction methods and the similar accuracy of TSE and Dixon imaging for automatic volumetry of VAT at 3 Tesla.18.
Jianmin Yuan Gregory Makris Andrew Patterson Ammara Usman Tilak Das Andrew Priest Zhongzhao Teng Sarah Hilborne Dario Prudencio Jonathan Gillard Martin Graves 《Magma (New York, N.Y.)》2018,31(1):191-199
Objective
This study aims to explore the relationship between plaque surface morphology and neovascularization using a high temporal and spatial resolution 4D contrast-enhanced MRI/MRA sequence.Materials and methods
Twenty one patients with either recent symptoms or a carotid artery stenosis ≥40% were recruited in this study. Plaque surface morphology and luminal stenosis were determined from the arterial phase MRA images. Carotid neovascularization was evaluated by a previously validated pharmacokinetic (PK) modeling approach. K trans (transfer constant) and v p (partial plasma volume) were calculated in both the adventitia and plaque.Results
Image acquisition and analysis was successfully performed in 28 arteries. Mean luminal stenosis was 44% (range 11–82%). Both adventitial and plaque K trans in ulcerated/irregular plaques were significantly higher than smooth plaques (0.079 ± 0.018 vs. 0.064 ± 0.011 min?1, p = 0.02; 0.065 ± 0.013 vs. 0.055 ± 0.010 min?1, p = 0.03, respectively). Positive correlations between adventitial K trans and v p against stenosis were observed (r = 0.44, p = 0.02; r = 0.55, p = 0.01, respectively).Conclusion
This study demonstrates the feasibility of using a single sequence to acquire both high resolution 4D CE-MRA and DCE-MRI to evaluate both plaque surface morphology and function. The results demonstrate significant relationships between lumen surface morphology and neovascularization.19.
Sophie Schumacher Florence Pache Judith Bellmann-Strobl Janina Behrens Petr Dusek Lutz Harms Klemens Ruprecht Petra Nytrova Sanjeev Chawla Thoralf Niendorf Ilya Kister Friedemann Paul Jens Wuerfel Tim Sinnecker 《Magma (New York, N.Y.)》2016,29(3):535-541
Objective
To quantify the periventricular venous density in neuromyelitis optica spectrum disease (NMOSD) in comparison to that in patients with multiple sclerosis (MS) and healthy control subjects.Materials and methods
Sixteen patients with NMOSD, 16 patients with MS and 16 healthy control subjects underwent 7.0-Tesla (7T) MRI. The imaging protocol included T2*-weighted (T2*w) fast low angle-shot (FLASH) and fluid-attenuated inversion recovery (FLAIR) sequences. The periventricular venous area (PVA) was manually determined by a blinded investigator in order to estimate the periventricular venous density in a region of interest-based approach.Results
No significant differences in periventricular venous density indicated by PVA were detectable in NMOSD versus healthy controls (p = 0.226). In contrast, PVA was significantly reduced in MS patients compared to healthy controls (p = 0.013).Conclusion
Unlike patients with MS, those suffering from NMOSD did not show reduced venous visibility. This finding may underscore primary and secondary pathophysiological differences between these two distinct diseases of the central nervous system.20.
Gwenaël Pagé Jérémie Bettoni Anne-Virginie Salsac Olivier Balédent 《Magma (New York, N.Y.)》2018,31(3):469-481