Recent multiple sclerosis (MS) MRI research has highlighted the need to move beyond the lesion-centric view and to develop and validate new MR imaging strategies that quantify the invisible burden of disease in the brain and establish much more sensitive and specific surrogate markers of clinical disability. One of the most promising of such measures is myelin-selective MRI that allows the acquisition of myelin water fraction (MWF) maps, a parameter that is correlated to brain white matter (WM) myelination. The aim of our study was to apply the newest myelin-selective MRI method, multi-component Driven Equilibrium Single Pulse Observation of T1 and T2 (mcDESPOT) in a controlled clinical MS pilot trial. This study was designed to assess the capabilities of this new method to explain differences in disease course and degree of disability in subjects spanning a broad spectrum of MS disease severity. The whole-brain isotropically-resolved 3D acquisition capability of mcDESPOT allowed for the first time the registration of 3D MWF maps to standard space, and consequently a formalized voxel-based analysis of the data. This approach combined with image segmentation further allowed the derivation of new measures of MWF deficiency: total deficient MWF volume (DV) in WM, in WM lesions, in diffusely abnormal white matter and in normal appearing white matter (NAWM). Deficient MWF volume fraction (DVF) was derived from each of these by dividing by the corresponding region volume. Our results confirm that lesion burden does not correlate well with clinical disease activity measured with the extended disability status scale (EDSS) in MS patients. In contrast, our measurements of DVF in NAWM correlated significantly with the EDSS score (R2 = 0.37; p < 0.001). The same quantity discriminated clinically isolated syndrome patients from a normal control population (p < 0.001) and discriminated relapsing–remitting from secondary-progressive patients (p < 0.05); hence this new technique may sense early disease-related myelin loss and transitions to progressive disease. Multivariate analysis revealed that global atrophy, mean whole-brain myelin water fraction and white matter atrophy were the three most important image-derived parameters for predicting clinical disability (EDSS). Overall, our results demonstrate that mcDESPOT-defined measurements in NAWM show great promise as imaging markers of global clinical disease activity in MS. Further investigation will determine if this measure can serve as a risk factor for the conversion into definite MS and for the secondary transition into irreversible disease progression.

No abstract

The PMPF for head and neck reconstruction is associated with a limitation in neck ROM attributed to a loss in extension and reduced shoulder strength and ROM.

Gadolinium-based contrast agents are used for enhancement during magnetic resonance imaging (MRI). Safety concerns have emerged over retained gadolinium in the globus pallidi. 1,2 Neurotoxic effects have been seen in animals and when gadolinium is given intrathecally in humans. 1 In July 2015, the US Food and Drug Administration stated that it was unknown whether gadolinium deposits were harmful. The substantia nigra (affected in Parkinson disease) directs voluntary movement via signals to the globus pallidi. Consequences of damage to the globus pallidi may include parkinsonian symptoms. 3 We conducted a population-based study to assess the association between gadolinium exposure and parkinsonism.Methods | Sunnybrook Hospital granted ethics approval and deemed the study exempt from participant consent. Multiple linked administrative databases from Ontario, Canada, were used. The population has universal health care, and medication coverage is provided for those older than 65 years. Using fee codes submitted by radiologists, all patients older than 66 years who underwent an initial MRI between April 2003 and March 2013 were identified. Patients whose

Balloons may not be required to treat all patients with carotid stenosis. A stent alone was feasible in 79% of patients, and 79% of patients were alive and free from ipsilateral stroke or restenosis at 1 year. Restenosis rates with this approach are higher than with conventional angioplasty and stent insertion. Carotid arteries with very severe stenoses (> 90%) and circumferential calcification may be more successfully treated with angioplasty combined with stent placement.