Table of Contents
Perspectives
Review Article
General Contents
- Heterogeneity of Cortical Lesion Susceptibility Mapping in Multiple Sclerosis
The authors characterized the susceptibility mapping of cortical lesions in patients with MS (n=36) and compared it with neuropathologic observations (n=16). Neuropathologic analysis revealed the presence of an intense band of microglia activation close to the pial membrane in subpial cortical lesions or to the WM border of leukocortical cortical lesions. The quantitative susceptibility mapping analysis revealed 131 cortical lesions classified as hyperintense; 33, as isointense; and 84, as hypointense. They conclude that cortical lesion susceptibility maps are highly heterogeneous, even at individual levels and that the quantitative susceptibility mapping hyperintensity edge found in proximity to the pial surface might be due to the subpial gradient of microglial activation.
- Synthetic MRI for Clinical Neuroimaging: Results of the Magnetic Resonance Image Compilation (MAGiC) Prospective, Multicenter, Multireader Trial
The authors performed a prospective multireader, multicasenoninferiority trial of 1526 images read by 7 blinded neuroradiologists with prospectively acquired synthetic and conventional brain MR imaging case-control pairs from 109 subjects with neuroimaging indications. Each case included conventional T1- and T2-weighted, T1 and T2 FLAIR, and STIR and/or proton density and synthetic reconstructions from multiple-dynamic multiple-echo imaging. Images were randomized and independently assessed. Overall synthetic MR imaging quality was similar to that of conventional proton-density, STIR, and T1- and T2-weighted contrast views across neurologic conditions. Artifacts were more common in synthetic T2 FLAIR, but were readily recognizable and did not mimic pathology.
- Differentiation of Enhancing Glioma and Primary Central Nervous System Lymphoma by Texture-Based Machine Learning
The authors evaluated the diagnostic performance of a machine-learning algorithm by using texture analysis of contrast-enhanced T1-weighted images for differentiation of primary central nervous system lymphoma (n=35) and enhancing glioma (n=71). The mean areas under the receiver operating characteristic curve were 0.877 for the support vector machine classifier; 0.878 for reader 1; 0.899 for reader 2; and 0.845 for reader 3. They conclude that support vector machine classification based on textural features of contrast-enhanced T1WI is noninferior to expert human evaluation in the differentiation of primary central nervous system lymphoma and enhancing glioma.
- Large Basilar Apex Aneurysms Treated with Flow-Diverter Stents
The authors report their experience treating basilar apex aneurysms with flow-diverter stents and evaluate their efficacy and safety profile in this specific condition. Of the 175 aneurysms treated with flow-diverter stents at their institution, 5 patients received flow-diverter stents for basilar apex aneurysms. The mean follow-up after stent deployment was 21 months. They conclude that flow diversion is a feasible technique with an efficacy demonstrated at a midterm follow-up, especially in the case of basilar apex aneurysm recurrences after previous endovascular treatments.
- Resting-State Seed-Based Analysis: An Alternative to Task-Based Language fMRI and Its Laterality Index
Eighteen healthy right-handed volunteers were prospectively evaluated with resting-state fMRI and task-based fMRI to assess language networks. The laterality indices of Broca and Wernicke areas were calculated by using task-based fMRI via a voxel-value approach. The authors performed seed-based resting-state fMRI connectivity analysis together with parameters such as amplitude of low-frequency fluctuation and fractional amplitude of low-frequency fluctuation (fALFF). fALFF can be used as an alternative to task-based fMRI for assessing language laterality. There was a strong positive correlation between the fALFF of the Broca area of resting-state fMRI with the laterality index of task-based fMRI.
- Clinically Feasible Microstructural MRI to Quantify Cervical Spinal Cord Tissue Injury Using DTI, MT, and T2*-Weighted Imaging: Assessment of Normative Data and Reliability
Forty healthy subjects underwent T2WI, DTI, magnetization transfer, and T2*WI at 3T in <35 minutes using standard hardware and pulse sequences. Cross-sectional area, fractional anisotropy, magnetization transfer ratio, and T2*WI WM/GM signal intensity ratio were calculated. Reliable multiparametric assessment of spinal cord microstructure is possible by using clinically suitable methods. These results establish normalization procedures and pave the way for clinical studies.
