Evaluating effects of normobaric oxygen therapy in acute stroke with MRI-based predictive models

<p>Abstract</p> <p>Background</p> <p>Voxel-based algorithms using acute multiparametric-MRI data have been shown to accurately predict tissue outcome after stroke. We explored the potential of MRI-based predictive algorithms to objectively assess the effects of normobaric oxygen therapy (NBO), an investigational stroke treatment, using data from a pilot study of NBO in acute stroke.</p> <p>Methods</p> <p>The pilot study of NBO enrolled 11 patients randomized to NBO administered for 8 hours, and 8 Control patients who received room-air. Serial MRIs were obtained at admission, during gas therapy, post-therapy, and pre-discharge. Diffusion/perfusion MRI data acquired at admission (pre-therapy) was used in generalized linear models to predict the risk of lesion growth at subsequent time points for both treatment scenarios: NBO or Control.</p> <p>Results</p> <p>Lesion volume sizes 'during NBO therapy' predicted by Control-models were significantly larger (P = 0.007) than those predicted by NBO models, suggesting that ischemic lesion growth is attenuated during NBO treatment. No significant difference was found between the predicted lesion volumes at later time-points. NBO-treated patients, despite showing larger lesion volumes on Control-models than NBO-models, tended to have reduced lesion growth.</p> <p>Conclusions</p> <p>This study shows that NBO has therapeutic potential in acute ischemic stroke, and demonstrates the feasibility of using MRI-based algorithms to evaluate novel treatments in early-phase clinical trials.</p

Cord cross-sectional area at foramen magnum as a correlate of disability in amyotrophic lateral sclerosis

Spinal cord atrophy is one of the hallmarks of amyotrophic lateral sclerosis (ALS); however, it is not routinely assessed in routine clinical practice. In the present study, we evaluated whether spinal cord cross-sectional area measured at the foramen magnum level using a magnetic resonance imaging head scan represents a clinically meaningful measure to be added to the whole-brain volume assessment. Using an active surface approach, we measured the cord area at the foramen magnum and brain parenchymal fraction on T1-weighted three-dimensional spoiled gradient recalled head scans in two groups of subjects: 23 patients with ALS (males/females,&nbsp;13/10; mean\u2009\ub1\u2009standard deviation [SD] age 61.7\u2009\ub1\u200910.3&nbsp;years; median ALS Functional Rating Scale-Revised score 39, range 27-46) and 18 age- and sex-matched healthy volunteers (mean\u2009\ub1\u2009SD age 55.7\u2009\ub1\u200910.2&nbsp;years). Spinal cord area at the foramen magnum was significantly less in patients than in control subjects and was significantly correlated with disability as measured with the ALS Functional Rating Scale-Revised (\u3c1\u2009=\u20090.593, p\u2009&lt;\u2009&nbsp;0.005). This correlation remained significant after taking into account inter-individual differences in brain parenchymal fraction (\u3c1\u2009=\u20090.684, p\u2009&lt;\u2009&nbsp;0.001). Our data show that spinal cord area at the foramen magnum correlates with disability in ALS independently of whole-brain atrophy, thus indicating its potential as a disease biomarker

Motor imagery as a function of disease severity in multiple sclerosis: An fMRI study

Motor imagery (MI) is defined as mental execution without any actual movement. While healthy adults usually show temporal equivalence, i.e., isochrony, between the mental simulation of an action and its actual performance, neurological disorders are associated with anisochrony. Unlike in patients with stroke and Parkinson disease, only a few studies have investigated differences of MI ability in multiple sclerosis (MS). However, the relationship among disease severity, anisochrony and brain activation patterns during MI has not been investigated yet. Here, we propose to investigate MI in MS patients using fMRI during a behavioral task executed with dominant/non-dominant hand and to evaluate whether anisochrony is associated with disease severity. Thirty-seven right-handed MS patients, 17 with clinically isolated syndrome (CIS) suggestive of MS and 20 with relapsing-remitting MS (RR-MS) and 20 right-handed healthy controls (HC) underwent fMRI during a motor task consisting in the actual or imaged movement of squeezing a foam ball with the dominant and non-dominant hand. The same tasks were performed outside the MRI room to record the number of actual and imagined ball squeezes, and calculate an Index of performance (IP) based on the ratio between actual and imagined movements. IP showed that a progressive loss of ability in simulating actions (i.e., anisochrony) more pronounced for non-dominant hand, was found as function of the disease course. Moreover, anisochrony was associated with activation of occipito-parieto-frontal areas that were more extensive at the early stages of the disease, probably in order to counteract the changes due to MS. However, the neural engagement of compensatory brain areas becomes more difficult with more challenging tasks, i.e., dominant vs. non-dominant hand, with a consequent deficit in behavioral performance. These results show a strict association between MI performance and disease severity, suggesting that, at early stages of the disease, anisochrony in MI could be considered as surrogate behavioral marker of MS severity

Upper limb motor rehabilitation impacts white matter microstructure in multiple sclerosis

Upper limb impairments can occur in patients with multiple sclerosis, affecting daily living activities; however there is at present no definite agreement on the best rehabilitation treatment strategy to pursue. Moreover, motor training has been shown to induce changes in white matter architecture in healthy subjects.This study aimed at evaluating the motor behavioral and white matter microstructural changes following a 2-month upper limb motor rehabilitation treatment based on task-oriented exercises in patients with multiple sclerosis.Thirty patients (18 females and 12 males; age. = 43.3. ±. 8.7. years) in a stable phase of the disease presenting with mild or moderate upper limb sensorimotor deficits were randomized into two groups of 15 patients each. Both groups underwent twenty 1-hour treatment sessions, three times a week. The "treatment group" received an active motor rehabilitation treatment, based on voluntary exercises including task-oriented exercises, while the "control group" underwent passive mobilization of the shoulder, elbow, wrist and fingers.Before and after the rehabilitation protocols, motor performance was evaluated in all patients with standard tests. Additionally, finger motor performance accuracy was assessed by an engineered glove.In the same sessions, every patient underwent diffusion tensor imaging to obtain parametric maps of fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity. The mean value of each parameter was separately calculated within regions of interest including the fiber bundles connecting brain areas involved in voluntary movement control: the corpus callosum, the corticospinal tracts and the superior longitudinal fasciculi.The two rehabilitation protocols induced similar effects on unimanual motor performance, but the bimanual coordination task revealed that the residual coordination abilities were maintained in the treated patients while they significantly worsened in the control group (p. = 0.002). Further, in the treatment group white matter integrity in the corpus callosum and corticospinal tracts was preserved while a microstructural integrity worsening was found in the control group (fractional anisotropy of the corpus callosum and corticospinal tracts: p. = 0.033 and p. = 0.022; radial diffusivity of the corpus callosum and corticospinal tracts: p. = 0.004 and p. = 0.008). Conversely, a significant increase of radial diffusivity was observed in the superior longitudinal fasciculi in both groups (p. = 0.02), indicating lack of treatment effects on this structure, showing damage progression likely due to a demyelination process.All these findings indicate the importance of administering, when possible, a rehabilitation treatment consisting of voluntary movements. We also demonstrated that the beneficial effects of a rehabilitation treatment are task-dependent and selective in their target; this becomes crucial towards the implementation of tailored rehabilitative approaches. © 2013 The Authors

Different MRI patterns in MS worsening after stopping fingolimod

Objective To analyze MRI images in patients with MS who experienced worsening of neurologic status (WNS) after stopping fingolimod (FTY).MethodsIn this retrospective study, demographic, clinical, and radiologic data of patients with MS who experienced WNS after stopping FTY were retrospectively collected. We introduced the "\u3b4Expanded Disability Status Scale (EDSS)-ratio" to identify patients who, after FTY withdrawal, showed an inflammatory flare-up exceeding the highest lifetime disease activity level. Patients with \u3b4EDSS-ratio &gt; 1 were enrolled in the study.ResultsEight patients were identified. The mean (SD) age of the 8 (7 female) patients was 35.3 (4.9) years. The mean FTY treatment duration was 3.1 (0.8) years. The mean FTY discontinuation-WNS interval was 4 (0.9) months. The 4 patients with \u3b4EDSS-ratio 65 2 developed severe monophasic WNS (EDSS score above 8.5), characterized by clinical features and MRI findings not typical of MS, which we classified as "tumefactive demyelination pattern" (TDL) and "Punctuated pattern" (PL). Conversely, patients whose \u3b4EDSS-ratio was between 1 and 2 had clinical features and brain MRI compatible with a more typical, even if aggressive, MS relapse. In patients with TDL and PL, the flare-up of inflammatory activity led to severe tissue damage resulting in T2 but also T1 lesion volume increase at 6-month follow-up.ConclusionsPeculiar MRI features (TDL and PL), different from a typical MS flare-up, might occur in some patients who experienced WNS after stopping FTY. Further studies, also involving immunologic biomarkers, are necessary to investigate TDL or PL pathophysiology

Quantitative MRI Harmonization to Maximize Clinical Impact: The RIN-Neuroimaging Network

Neuroimaging studies often lack reproducibility, one of the cardinal features of the scientific method. Multisite collaboration initiatives increase sample size and limit methodological flexibility, therefore providing the foundation for increased statistical power and generalizable results. However, multisite collaborative initiatives are inherently limited by hardware, software, and pulse and sequence design heterogeneities of both clinical and preclinical MRI scanners and the lack of benchmark for acquisition protocols, data analysis, and data sharing. We present the overarching vision that yielded to the constitution of RIN-Neuroimaging Network, a national consortium dedicated to identifying disease and subject-specific in-vivo neuroimaging biomarkers of diverse neurological and neuropsychiatric conditions. This ambitious goal needs efforts toward increasing the diagnostic and prognostic power of advanced MRI data. To this aim, 23 Italian Scientific Institutes of Hospitalization and Care (IRCCS), with technological and clinical specialization in the neurological and neuroimaging field, have gathered together. Each IRCCS is equipped with high- or ultra-high field MRI scanners (i.e., ≥3T) for clinical or preclinical research or has established expertise in MRI data analysis and infrastructure. The actions of this Network were defined across several work packages (WP). A clinical work package (WP1) defined the guidelines for a minimum standard clinical qualitative MRI assessment for the main neurological diseases. Two neuroimaging technical work packages (WP2 and WP3, for clinical and preclinical scanners) established Standard Operative Procedures for quality controls on phantoms as well as advanced harmonized quantitative MRI protocols for studying the brain of healthy human participants and wild type mice. Under FAIR principles, a web-based e-infrastructure to store and share data across sites was also implemented (WP4). Finally, the RIN translated all these efforts into a large-scale multimodal data collection in patients and animal models with dementia (i.e., case study). The RIN-Neuroimaging Network can maximize the impact of public investments in research and clinical practice acquiring data across institutes and pathologies with high-quality and highly-consistent acquisition protocols, optimizing the analysis pipeline and data sharing procedures

Ruptured lenticulostriate artery aneurysm: a report of a case treated with endovascular embolisation

A 65-year-old woman presented to the emergency department with sudden onset of left-sided weakness, headache and vomiting. A cerebral CT showed an acute intracerebral haemorrhage involving the right caudate nucleus and lentiform nucleus with mild midline shift and intraventricular extension. CT angiography did not reveal aneurysm or other vascular anomaly. Conventional cerebral angiography demonstrated a 3mm right medial lenticulostriate branch aneurysm, arising from the right anterior cerebral artery (ACA). Endovascular treatment was performed from the left internal carotid via the anterior communicating artery into the right ACA. Complete occlusion was achieved with injection of N-butyl-2-cyanoacrylate. The patient had neurological rehabilitation during hospitalisation followed by outpatient physical therapy. Two years later, clinical follow-up demonstrated excellent recovery