Sudden hearing loss as an early detector of multiple sclerosis: a systematic review

To evaluate whether Sudden Sensorineural Hearing Loss (S-SNHL) may be an early symptom of Multiple Sclerosis (MS). A systematic review was conducted using the following keywords: "Multiple sclerosis, hearing loss, sudden hearing loss, vertigo, tinnitus, magnetic resonance imaging, otoacoustic emission, auditory brainstem responses, white matter lesions, sensorineural hearing loss, symptoms of MS and otolaryngology, nerve disease and MS". Only the articles that included results of at least one auditory test and MRI were considered. We evaluated the prevalence of SNHL in patients with MS, the presence of different forms of SNHL (S-SNHL and Progressive SNHL (P-SNHL)) and their correlation with the stage of MS, the results of electrophysiological tests, and the location (if any) of MS lesions as detected by white matter hyperintensities in the MRI. We reviewed a total of 47 articles, which included 29 case reports, 6 prospective studies, 6 cohort studies, 4 case-control studies, and 2 retrospective studies. 25% of patients suffered from SNHL. S-SNHL typically occurred in the early stage of the disease (92% of patients) and was the only presenting symptom in 43% of female subjects. Instead, P-SNHL occurred in the late stage of MS (88% of patients). Auditory Brainstem Responses (ABR) were abnormal in all MS patients with S-SNHL. When S-SNHL appeared during the early stage of the disease, MS lesions were found in the brain in 60% of patients and in the Internal Auditory Canal in 40% of patients. ABR remained abnormal after recovery. S-SNHL can be an early manifestation of MS and should always be considered in the differential diagnosis of this condition, especially in women. The pathophysiology can be explained by the involvement of microglia attacking the central and/or peripheral auditory pathways as indicated by WMHs

Structural model correlation using large admissible perturbations incognate space

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76957/1/AIAA-10863-901.pd

Nonlinear incremental inverse perturbation method for structural redesign

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76715/1/AIAA-1983-892-392.pd

Admissible large perturbations in structural redesign

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76363/1/AIAA-10551-828.pd

Large deformation three-dimensional static analysis of deep water marine risers

The problem of static three-dimensional, nonlinear, large deformation response of a marine riser is formulated within small strain theory and solved numerically. This type of analysis is necessary, for the new generation of drilling and production risers. The mathematical model takes properly into account the effects of internal and external pressure and the complete nonlinear boundary conditions, without linearizing the follower forces. The extensibility or inextensibility condition is used as the constitutive relation in the tangential direction. Torsion and bending are coupled. The external load and the boundary conditions are deformation dependent. A solution method is developed based on an incremental finite element algorithm, which involves a prediction-correction scheme. In the correction phase deformation dependent quantities are updated. The extensibility or inextensibility condition is used to reduce the degrees of freedom of the system. The numerical results of the developed computer code compare very well with available semi-analytical and numerical solutions. Three numerical applications are used to demonstrate the importance of large deformation, nonlinear and three-dimensional analyses.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25547/1/0000089.pd

Inverse perturbation method for structural redesign with frequency and mode shape constraints

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76581/1/AIAA-8777-705.pd

Reduced Venous Blood Oxygen Saturation May Associate with Cognitive Decline in Patients with Multiple Sclerosis

Introduction: Reduced brain oxygen metabolism may be associated with neuronal activity in individuals with Multiple sclerosis (MS). Quantitative susceptibility mapping (QSM), an advanced MRI technique, can measure venous blood oxygen saturation via deoxyhemoglobin levels. It remains unknown whether QSM-derived venous blood susceptibility can be used as an imaging biomarker of neuronal activity in MS. The objective of this study was to investigate the susceptibility of internal cerebral veins (ICVs) in patients with relapsing-remitting MS (RRMS), and their correlations with clinical measures. Methods: We recruited 18 patients with RRMS and 10 age-matched healthy controls (HC). Participants were scanned on a 3T MRI, generating QSM data. We performed clinical measures, including the paced auditory serial addition test (PASAT), an index of cognitive function. The total lesion load (TLL) and the susceptibility of the ICVs (χicv) were measured through manually delineated regions-of-interest on clinical MRI and QSM images, respectively. We compared the χicv between cohorts using Wilcoxon rank sum test. Linear regression was used to correlate χicv with clinical scores in MS patients. Results: There were significantly reduced χicv (p = 0.026) in RRMS patients (212.4 ± 30.1 ppb) compared to HCs (239.4 ± 25.9 ppb). The χicv was moderately correlated with PASAT (r = 0.258, p \u3c 0.031) and TLL (r = -0.256, p \u3c 0.032) in MS patients. Conclusions: This study provides first-of-its-kind evidence that reduced oxygen consumption in deep cerebral regions draining to the ICVs may be associated with cognitive decline in MS patients

Redesign of plates by large admissible perturbations

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76482/1/AIAA-12089-360.pd

The effects of spring stiffness on vortex-induced vibration for energy generation

Vortex-induced vibration (VIV) is the turbulent motion induced on bluff body that generates alternating lift forces and results in irregular movement of the body. VIV-powered system seems a good idea in greening the energy sector and most importantly is its ability to take advantages of low current speed of water to generate electricity. This paper aims to investigate the effects of spring stiffness on the characteristic of VIV. The study is important in order to maximize these potentially destructive vibrations into a valuable resource of energy. Five cylinders with the range of 0.25 to 2.00 inch diameter are tested to study the behavior of VIV. Results from this experiment indicates that, the 2.0 inch cylinder gave the lowest error in frequency ratio which is 1.1% and have a high potential of lock-in condition to occur. In term of maximum amplitude, this cylinder gave the highest amplitude of oscillation motion that is equal to 0.0065 m

Ocrelizumab versus Interferon Beta-1a in Relapsing Multiple Sclerosis

Supported by F. Hoffmann–La Roche