Engagement in Primary Prevention Program among Rural Veterans With Osteoporosis Risk.

A primary osteoporosis prevention program using a virtual bone health team (BHT) was implemented to comanage the care of rural veterans in the Mountain West region of the United States. The BHT identified, screened, and treated rural veterans at risk for osteoporosis using telephone and United States Postal Service communications. Eligibility was determined by regular use of Veterans Health Administration primary care, age 50 or older, and evidence of fracture risk. This study was conducted to identify demographic and clinical factors associated with the acceptance of osteoporosis screening and the initiation of medication where indicated. A cross-sectional cohort design (N = 6985) was utilized with a generalized estimating equation and logit link function to account for facility-level clustering. Fully saturated and reduced models were fitted using backward selection. Less than a quarter of eligible veterans enrolled in BHT's program and completed screening. Factors associated with a lower likelihood of clinic enrollment included being of older age, unmarried, greater distance from VHA services, having a copayment, prior fracture, or history of rheumatoid arthritis. A majority of veterans with treatment indication started medication therapy (N = 453). In this subpopulation, Fisher's exact test showed a significant association between osteoporosis treatment uptake and a history of two or more falls in the prior year, self-reported parental history of fracture, current smoking, and weight-bearing exercise. The BHT was designed to reduce barriers to screening; however, for this population cost and travel continue to limit engagement. The remarkable rate of medication initiation notwithstanding, low enrollment reduces the impact of this primary prevention program, and findings pertaining to fracture, smoking, and exercise imply that health beliefs are an important contributing factor. Efforts to identify and address barriers to osteoporosis screening and treatment, such as clinical factors, social determinants of health, and health beliefs, may pave the way for effective implementation of population bone health care delivery systems. Published 2022. This article is a U.S. Government work and is in the public domain in the USA. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Reliability of multi-site UK Biobank MRI brain phenotypes for the assessment of neuropsychiatric complications of SARS-CoV-2 infection: The COVID-CNS travelling heads study.

INTRODUCTION: Magnetic resonance imaging (MRI) of the brain could be a key diagnostic and research tool for understanding the neuropsychiatric complications of COVID-19. For maximum impact, multi-modal MRI protocols will be needed to measure the effects of SARS-CoV-2 infection on the brain by diverse potentially pathogenic mechanisms, and with high reliability across multiple sites and scanner manufacturers. Here we describe the development of such a protocol, based upon the UK Biobank, and its validation with a travelling heads study. A multi-modal brain MRI protocol comprising sequences for T1-weighted MRI, T2-FLAIR, diffusion MRI (dMRI), resting-state functional MRI (fMRI), susceptibility-weighted imaging (swMRI), and arterial spin labelling (ASL), was defined in close approximation to prior UK Biobank (UKB) and C-MORE protocols for Siemens 3T systems. We iteratively defined a comparable set of sequences for General Electric (GE) 3T systems. To assess multi-site feasibility and between-site variability of this protocol, N = 8 healthy participants were each scanned at 4 UK sites: 3 using Siemens PRISMA scanners (Cambridge, Liverpool, Oxford) and 1 using a GE scanner (King's College London). Over 2,000 Imaging Derived Phenotypes (IDPs), measuring both data quality and regional image properties of interest, were automatically estimated by customised UKB image processing pipelines (S2 File). Components of variance and intra-class correlations (ICCs) were estimated for each IDP by linear mixed effects models and benchmarked by comparison to repeated measurements of the same IDPs from UKB participants. Intra-class correlations for many IDPs indicated good-to-excellent between-site reliability. Considering only data from the Siemens sites, between-site reliability generally matched the high levels of test-retest reliability of the same IDPs estimated in repeated, within-site, within-subject scans from UK Biobank. Inclusion of the GE site resulted in good-to-excellent reliability for many IDPs, although there were significant between-site differences in mean and scaling, and reduced ICCs, for some classes of IDP, especially T1 contrast and some dMRI-derived measures. We also identified high reliability of quantitative susceptibility mapping (QSM) IDPs derived from swMRI images, multi-network ICA-based IDPs from resting-state fMRI, and olfactory bulb structure IDPs from T1, T2-FLAIR and dMRI data. CONCLUSION: These results give confidence that large, multi-site MRI datasets can be collected reliably at different sites across the diverse range of MRI modalities and IDPs that could be mechanistically informative in COVID brain research. We discuss limitations of the study and strategies for further harmonisation of data collected from sites using scanners supplied by different manufacturers. These acquisition and analysis protocols are now in use for MRI assessments of post-COVID patients (N = 700) as part of the ongoing COVID-CNS study.

Template-based field map prediction for rapid whole brain B0 shimming.

PURPOSE: In typical MRI protocols, time is spent acquiring a field map to calculate the shim settings for best image quality. We propose a fast template-based field map prediction method that yields near-optimal shims without measuring the field. METHODS: The template-based prediction method uses prior knowledge of the B0 distribution in the human brain, based on a large database of field maps acquired from different subjects, together with subject-specific structural information from a quick localizer scan. The shimming performance of using the template-based prediction is evaluated in comparison to a range of potential fast shimming methods. RESULTS: Static B0 shimming based on predicted field maps performed almost as well as shimming based on individually measured field maps. In experimental evaluations at 7 T, the proposed approach yielded a residual field standard deviation in the brain of on average 59 Hz, compared with 50 Hz using measured field maps and 176 Hz using no subject-specific shim. CONCLUSIONS: This work demonstrates that shimming based on predicted field maps is feasible. The field map prediction accuracy could potentially be further improved by generating the template from a subset of subjects, based on parameters such as head rotation and body mass index. Magn Reson Med 80:171-180, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Descriptive Epidemiology of Voice Disorders in Rheumatoid Arthritis: Prevalence, Risk Factors, and Quality of Life Burden.

OBJECTIVES: Rheumatoid arthritis (RA) is an autoimmune inflammatory disease which may adversely affect phonatory function. This study aimed to establish the prevalence, risks, and quality of life effects of voice disorders in RA. STUDY DESIGN: This is a cross-sectional, descriptive epidemiology study. METHODS: One hundred individuals with RA underwent a telephone interview to determine the frequency, severity, risks associated with, and quality of life burden of voice disorders. The results were analyzed using summary statistics, frequencies, chi-square tests, regression analysis, and risk ratios (P < 0.05). RESULTS: Thirty-five percent of participants with RA reported a current voice disorder which was chronic and long-standing in most cases. The prevalence of a current voice disorder did not significantly differ across age, sex, medication use, voice use patterns, medical history, or RA severity. These chronic voice disorders produced significant adverse effects on both voice-related quality of life and short form 36 health-related quality of life scales. Specific voice symptoms such as "voice-related discomfort" and "chronic throat dryness" contributed disproportionately to the quality of life burden. Of those participants with a voice disorder, only 37% had ever sought professional help to improve their voice. CONCLUSIONS: These results indicate that voice disorders are common in RA and produce significant adverse effects on quality of life. Further research is necessary to better understand the origin of these disorders and their potential response to treatment.

The Quality of Life Burden Associated With Voice Disorders in Sjögren's Syndrome.

OBJECTIVES: This study examined quality of life burden of voice disorders in Sjögren's syndrome (SS). METHODS: Patients with SS (n = 101) completed interviews involving patient-reported histories of voice disorders, specific voice symptoms, SS disease severity, the Voice-Related Quality of Life (V-RQOL), and the general health-related quality of life Short Form 36 (SF-36) questionnaires. Relationships among voice symptoms, disease severity, and quality-of-life measures were examined and compared with patient-reported voice disorders. RESULTS: Significant correlations were observed among voice symptoms, disease severity, V-RQOL, SF-36, and patient-reported voice disorders (P < .05). Patients with SS who reported a voice disorder experienced a greater burden on general quality of life as compared with those without voice disorders. Specific voice symptoms significantly correlated with reduced SF-36 scores included frequent throat-clearing, throat soreness, difficulty projecting, and vocal discomfort. Despite the added burden of a voice disorder on quality of life in SS, voice-related treatment seeking was low (15.8%). However, the majority of patients who received voice treatment reported voice improvement. CONCLUSIONS: Individuals with SS frequently experience voice disorders and specific voice-related symptoms that are associated with reduced quality of life. These findings have important implications for voice referral practices and voice disorder symptom management in this population.

A model for extra-axonal diffusion spectra with frequency-dependent restriction.

PURPOSE: In the brain, there is growing interest in using the temporal diffusion spectrum to characterize axonal geometry in white matter because of the potential to be more sensitive to small pores compared to conventional time-dependent diffusion. However, analytical expressions for the diffusion spectrum of particles have only been derived for simple, restricting geometries such as cylinders, which are often used as a model for intra-axonal diffusion. The extra-axonal space is more complex, but the diffusion spectrum has largely not been modeled. We propose a model for the extra-axonal space, which can be used for interpretation of experimental data. THEORY AND METHODS: An empirical model describing the extra-axonal space diffusion spectrum was compared with simulated spectra. Spectra were simulated using Monte Carlo methods for idealized, regularly and randomly packed axons over a wide range of packing densities and spatial scales. The model parameters are related to the microstructural properties of tortuosity, axonal radius, and separation for regularly packed axons and pore size for randomly packed axons. RESULTS: Forward model predictions closely matched simulations. The model fitted the simulated spectra well and accurately estimated microstructural properties. CONCLUSIONS: This simple model provides expressions that relate the diffusion spectrum to biologically relevant microstructural properties.

Implementation and assessment of diffusion-weighted partial Fourier readout-segmented echo-planar imaging.

Single-shot echo-planar imaging has been used widely in diffusion magnetic resonance imaging due to the difficulties in correcting motion-induced phase corruption in multishot data. Readout-segmented EPI has addressed the multishot problem by introducing a two-dimensional nonlinear navigator correction with online reacquisition of uncorrectable data to enable acquisition of high-resolution diffusion data with reduced susceptibility artifact and T*(2) blurring. The primary shortcoming of readout-segmented EPI in its current form is its long acquisition time (longer than similar resolution single-shot echo-planar imaging protocols by approximately the number of readout segments), which limits the number of diffusion directions. By omitting readout segments at one side of k-space and using partial Fourier reconstruction, readout-segmented EPI imaging times could be reduced. In this study, the effects of homodyne and projection onto convex sets reconstructions on estimates of the fractional anisotropy, mean diffusivity, and diffusion orientation in fiber tracts and raw T(2)- and trace-weighted signal are compared, along with signal-to-noise ratio results. It is found that projections onto convex sets reconstruction with 3/5 segments in a 2 mm isotropic diffusion tensor image acquisition and 9/13 segments in a 0.9 × 0.9 × 4.0 mm(3) diffusion-weighted image acquisition provide good fidelity relative to the full k-space parameters. This allows application of readout-segmented EPI to tractography studies, and clinical stroke and oncology protocols.

Modeling SSFP functional MRI contrast in the brain.

Steady-state free precession (SSFP) has recently been proposed for function MRI because of the potential for reducing image distortion and signal dropout. Several different contrast mechanisms have been suggested to explain the reported observations, but there has been limited work comparing theory with experiment in the brain. Moreover, the detailed work that has considered oxygen-dependent signal in SSFP outside the brain has focused on R(2) effects in the pass band, and largely neglected the signal contrast that occurs due to off-resonance effects. The article describes a model for SSFP functional contrast based on the convolution of the theoretical SSFP profile with the underlying frequency distribution. It is demonstrated that such a model must account for the effects of diffusion, which can alter the apparent R(2) and linespread. Monte Carlo simulations are used to calibrate corrections for these terms. This new model has the computational efficiency of the convolution model while encapsulating information from more time-consuming Monte Carlo simulations. This corrected convolution model is shown to agree well with experimental data, and model predictions and limitations are discussed.