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K. Vecchiato A. Egloff O. Carney A. Siddiqui E. Hughes L. Dillon K. Colford E. Green R.P.A.G. Texeira A.N. Price G. Ferrazzi J.V. Hajnal D.W. Carmichael L. Cordero-Grande J. OMuircheartaigh 《AJNR. American journal of neuroradiology》2021,42(4):774
BACKGROUND AND PURPOSE:Head motion causes image degradation in brain MR imaging examinations, negatively impacting image quality, especially in pediatric populations. Here, we used a retrospective motion correction technique in children and assessed image quality improvement for 3D MR imaging acquisitions.MATERIALS AND METHODS:We prospectively acquired brain MR imaging at 3T using 3D sequences, T1-weighted MPRAGE, T2-weighted TSE, and FLAIR in 32 unsedated children, including 7 with epilepsy (age range, 2–18 years). We implemented a novel motion correction technique through a modification of k-space data acquisition: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). For each participant and technique, we obtained 3 reconstructions as acquired (Aq), after DISORDER motion correction (Di), and Di with additional outlier rejection (DiOut). We analyzed 288 images quantitatively, measuring 2 objective no-reference image quality metrics: gradient entropy (GE) and MPRAGE white matter (WM) homogeneity. As a qualitative metric, we presented blinded and randomized images to 2 expert neuroradiologists who scored them for clinical readability.RESULTS:Both image quality metrics improved after motion correction for all modalities, and improvement correlated with the amount of intrascan motion. Neuroradiologists also considered the motion corrected images as of higher quality (Wilcoxon z = −3.164 for MPRAGE; z = −2.066 for TSE; z = −2.645 for FLAIR; all P < .05).CONCLUSIONS:Retrospective image motion correction with DISORDER increased image quality both from an objective and qualitative perspective. In 75% of sessions, at least 1 sequence was improved by this approach, indicating the benefit of this technique in unsedated children for both clinical and research environments.Head motion is a common cause of image degradation in brain MR imaging. Motion artifacts negatively impact MR image quality and therefore radiologists’ capacity to read the images, ultimately affecting patient clinical care.1 Motion artifacts are more common in noncompliant patients,2 but even in compliant adults, intrascan movement is reported in at least 10% of cases.3 For children who require high-resolution MR images, obtaining optimal image quality can be challenging, owing to the requirement to stay still over long durations needed for acquisition.4 Sedation can be an option, but it carries higher risks, costs, and preparation and recovery time.5In conditions such as intractable focal epilepsy, identification of an epileptogenic lesion is clinically important to guide surgical treatment. However, these lesions can be visually subtle, particularly in children in whom subtle cortical dysplasias are more common.6 Dedicated epilepsy MR imaging protocols use high-resolution 3D sequences to allow better cortical definition and free reformatting of orientation but involve acquisition times in the order of minutes, so data collection becomes more sensitive to motion.7For children in particular, multiple strategies are available for minimizing motion during MR examinations. Collaboration with play specialists using mock scanners and training or projecting a cartoon are good approaches to reduce anxiety.8,9 These tools are not always available in clinical radiology and, even with these strategies, motion can still be an issue.10 Different scanning approaches to correct for intrascan motion have been proposed. Broadly, prospective methods track head motion in real time and modify the acquisition directions accordingly.11 These approaches are applicable to a wide range of sequences but require optical systems with external tracking markers, sometimes uncomfortable or impractical, and extra setup can ultimately result in longer examinations. Furthermore, these approaches may also not be robust to continuous motion.11-13 Retrospective techniques have also been proposed, in some cases relying on imaging navigators that are not compatible with all standard sequences or contrasts.12Here, we use a more general retrospective motion correction technique: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). In this method, k-space samples are reordered to enable retrospective motion correction during image reconstruction.14 Our hypothesis is that DISORDER improves clinical MR imaging quality and readability. To assess its use for clinical sequences, we acquired a dedicated epilepsy MR imaging protocol in 32 children across a wide age range. We used both objective image quality metrics and expert neuroradiologist ratings to evaluate the outcome after motion correction. 相似文献
44.
A simple, safe, accurate, and reproducible technique for measuring the transmural electrical potential difference (PD) of the esophagus has been developed. This technique, a modification of those previously used, allows simultaneous correlation of the PD profile with the pressure profile obtained during routine manometry. With this technique, a subcutaneous reference bridge was shown to detect accurately a lumen-negative electrical orientation for the esophageal PD in three species: rabbit, opossum, and man. A characteristic and reproducible PD profile was present for each species. In the rabbit the gastric PD was low,--12 mv, relative to the body of the esophagus,--26 to -29 mv. In contrast, both opossum and man had relatively high gastric PD's ( -36 to -43 mv) when compared to esophageal PD's ( -12 to -25 mv). In the rabbit and opossum, the PD in the lower esophageal sphincter ( -5 to -6 mv) was less than both gastric or esophageal PD's, whereas in human beings the lower esophageal sphincter PD ( -22 mv) was between gastric and esophageal values. In vitro PD measurements and histological studies of opossum esophagus revealed differences in the epithelium which correlated with the different in vivo PD's. 相似文献
45.
Inhibitory neuropeptides and intrinsic inhibitory innervation of descending human colon 总被引:2,自引:0,他引:2
Dr. Timothy R. Koch MD J. Aidan Carney MD PhD V. L. W. Go MD Joseph H. Szurszewski PhD 《Digestive diseases and sciences》1991,36(6):712-718
The effects of aging on inhibitory neuropeptide concentrations and intrinsic inhibitory innervation of circular muscle were investigated using normal descending colon obtained at surgery. Immunoreactive vasoactive intestinal peptide, peptide histidine-methionine, met5-enkephalin, neuropeptide Y, and somatostatin were extracted from specimens of muscularis externa (patient ages: 19–84 years) and measured by radioimmunoassay. Intracellular electrical activity was recorded from strips of circular muscle (patients ages: 49–84 years) using glass microelectrodes; inhibitory junction potentials were evoked by electrical field stimulation. There were no significant differences (t tests:P>0.05) between neuropeptide concentrations in patients<70 years old (N=28) compared to patients70 years old (N=12). However, the amplitude of inhibitory junction potentials declined with increasing patient age (r=–0.58,P=0.02,N=16), with no change in resting membrane potentials (r=0.22;P>0.05). The decline in amplitude in women (r=–0.68,P=0.03,N=9) preceded the decline in men (r=–0.62,P=0.10,N=7). Age-related decline in inhibitory junction potentials could be related to decreased: density of inhibitory nerves, release of inhibitory neurotransmitter, density of binding sites for inhibitory neurotransmitter on smooth muscle, or a combination thereof. Alternatively, this decline might represent a change in interaction of inhibitory neurotransmitter with the smooth muscle membrane, such as a change in coupling of binding site with the potassium channel, decreased number of potassium channels, or altered permeability of the potassium channel.This study was supported in part by the National Institutes of Health (DK 17238 and DK 34988), and by VA Medical Research funds. 相似文献
46.
Samuel O. Ewalefo Malcolm Dombrowski Takashi Hirase Jorge L. Rocha Mitchell Weaver Alex Kline Dwayne Carney MaCalus V. Hogan 《Current reviews in musculoskeletal medicine》2018,11(4):546-557
Purpose of Review
Trauma is the principle cause of osteoarthritis in the ankle, which is associated with significant morbidity. This review highlights the current literature for the purpose of bringing the reader up-to-date on the management of posttraumatic ankle arthritis, describing treatment efficacy, indications, contraindications, and complications.Recent Findings
Recent studies on osteoarthritis have demonstrated variability among anatomic locations regarding the mechanisms and rates of development for posttraumatic osteoarthritis, which are attributed to newly discovered biological differences intrinsic to each joint. Regarding surgical management of posttraumatic ankle arthritis, osteochondral allograft transplantation of the talus, and supramalleolar osteotomies have demonstrated promising results. Additionally, the outpatient setting was found to be appropriate for managing pain following total ankle arthroplasty, associated with low complication rates and no readmission.Summary
Management for posttraumatic ankle arthritis is generally progressive. Initial treatment entails nonpharmacologic options with surgery reserved for posttraumatic ankle arthritis refractory to conservative treatment. Patient demographics and lifestyles should be carefully considered when formulating a management strategy, as outcomes are dependent upon the satisfaction of each set of respective criteria. Ultimately, the management of posttraumatic ankle arthritis should be individualized to satisfy the needs and desires, which are specific to each patient.47.
Today’s public health crises, as exemplified by the Ebola outbreak, lead to dramatic calls to action that typically include improved electronic monitoring systems to better prepare for, and respond to, similar occurrences in the future. Even a preliminary public health informatics evaluation of the current Ebola crisis exposes the need for enhanced coordination and sharing of trustworthy public health intelligence.We call for a consumer-centric model of public health intelligence and the formation of a national center to guide public health intelligence gathering and synthesis.Sharing accurate and actionable information with government agencies, health care practitioners, policymakers, and, critically, the general public, will mark a shift from doing public health surveillance on people to doing public health surveillance for people.The Ebola crisis continues to have a major impact on the nation and much of the world. Ebola and similar critical public health and health care delivery crises lead to dramatic calls to action that seek to understand the nature of the problem, to develop strategic intelligence on the scope and reach of the problem, to develop tactical responses, and to build protections to manage future risk. Typically, the creation of electronic monitoring systems to better prepare for, and respond to, similar occurrences in the future is indicated.Public health crises can expose failures in (1) the process (e.g., events, task performance, or actions), (2) policy (e.g., absent, outdated, poorly disseminated, or unevenly implemented guidelines), and (3) responsiveness (e.g., poorly coordinated or deployed resources, inadequate, ineffective strategic responses, etc.). The common thread underlying failures associated with such public health crises is deficiencies in actionable intelligence that inform process, policy, and responsiveness. Once actionable intelligence has been appropriately gathered and disseminated, adequate resources must be deployed to implement containment and preventive interventions.Public health system informatics is the field designed specifically to assess the national capability of our combined network of public health departments and health care delivery sites to intelligently manage crises and ensure population safety. Public health informatics activity builds, maintains, and evaluates the national intelligence required to address the full spectrum of decision-making needs and includes: individual health consumers seeking information about their individual risk and the resources to assist them in times of need; health care providers seeking to understand and interpret practice guidelines; public health program managers seeking to organize proper responses, deploy resources, and communicate the progress in mitigating and eventually eliminating the threat; and policymakers governing national public health system integrity.Even a preliminary public health system informatics evaluation of the current Ebola crisis highlights several failures in the gathering, management, dissemination, and responsiveness of national public health intelligence. Such an examination offers some critical lessons and helps us to better understand the fundamental components of maintaining a heightened national public health intelligence capability, not only for Ebola, but in general, for all public health crises. 相似文献
48.
Iftikhar J. Kullo Janet Olson Xiao Fan Merin Jose Maya Safarova Carmen Radecki Breitkopf Erin Winkler David C. Kochan Sara Snipes Joel E. Pacyna Meaghan Carney Christopher G. Chute Jyoti Gupta Sheethal Jose Eric Venner Mullai Murugan Yunyun Jiang Magdi Zordok Stephen N. Thibodeau 《Mayo Clinic proceedings. Mayo Clinic》2018,93(11):1600-1610
Objectives
To identify clinically actionable genetic variants from targeted sequencing of 68 disease-related genes, estimate their penetrance, and assess the impact of disclosing results to participants and providers.Patients and Methods
The Return of Actionable Variants Empirical (RAVE) Study investigates outcomes following the return of pathogenic/likely pathogenic (P/LP) variants in 68 disease-related genes. The study was initiated in December 2016 and is ongoing. Targeted sequencing was performed in 2533 individuals with hyperlipidemia or colon polyps. The electronic health records (EHRs) of participants carrying P/LP variants in 36 cardiovascular disease (CVD) genes were manually reviewed to ascertain the presence of relevant traits. Clinical outcomes, health care utilization, family communication, and ethical and psychosocial implications of disclosure of genomic results are being assessed by surveys, telephone interviews, and EHR review.Results
Of 29,208 variants in the 68 genes, 1915 were rare (frequency <1%) and putatively functional, and 102 of these (60 in 36 CVD genes) were labeled P/LP based on the American College of Medical Genetics and Genomics framework. Manual review of the EHRs of participants (n=73 with P/LP variants in CVD genes) revealed that 33 had the expected trait(s); however, only 6 of 45 participants with non–familial hypercholesterolemia (FH) P/LP variants had the expected traits.Conclusion
Expected traits were present in 13% of participants with P/LP variants in non-FH CVD genes, suggesting low penetrance; this estimate may change with additional testing performed as part of the clinical evaluation. Ongoing analyses of the RAVE Study will inform best practices for genomic medicine. 相似文献49.
David M. Wilson III John J. Tentler James P. Carney Teresa M. Wilson Mark R. Kelley 《Alcoholism, clinical and experimental research》1994,18(5):1267-1271
Alcohol has clearly been associated with an increase of cancers in numerous tissues, including the respiratory tract, colon, rectum, liver, but especially the esophagus, larynx, pharynx, and mouth. Alcohol alone has not been shown to be a mutagen until it is converted to acetaldehyde and, therefore, alcohol presumably acts as a cocarcinogen. Previous data has shown that alcohol concentrations of 2% or greater inhibits DNA repair, and in light of the widespread consumption of alcoholic beverages with alcohol contents ranging from 4 to 5% (beer and wine coolers) to 50% (whiskey), interest in determining the mechanism(s) responsible for alcohol-induced carcinogenesis has heightened. Although previous studies, in intact rats, have investigated the effects of chronic alcohol exposure on some aspects of DNA repair, we have begun to address the effects of acute or "binge" alcohol exposure on mammalian DNA repair. Toward this end, we report the inhibition of O6 -methylguanine-DNA methyltransferase (MGMT) by a single intraperitoneal injection of 30% ethanol in adult male castrated rats. This inhibition lasted for at least 24 hr. We also observed a dose-response effect of ethanol on MGMT activity, again only in the castrated rats. The finding of ethanol's effect on MGMT activity in castrated and not intact rats implies a hormonal component of MGMT DNA repair response, which has only been alluded to in past research. 相似文献
50.
[Purpose] The purpose of this study was to investigate the use of smartphones by
university students in selected areas, their musculoskeletal symptoms, and the associated
hazard ratio. [Subjects and Methods] This involved the completion of a self-administered
questionnaire by dental hygiene students in Seoul, Gyeonggido, and Gyeongsangbukdo. The
292 completed copies of the questionnaire were then analyzed. [Results] The most painful
body regions after the use of smartphones were found to be the shoulders and neck. In the
musculoskeletal system, back pain was found to have a positive correlation with the size
of the smartphone’s liquid crystal display (LCD) screen, and pain in legs and feet were
found to have a negative correlation with the length of time that the smartphone was used.
As a result, it was revealed that the use of a smartphone was correlated with
musculoskeletal symptoms. [Conclusion] Therefore, in today’s environment, where the use of
smartphones is on the rise, it is necessary to improve the ways that they are used and to
develop a preventive program to alleviate the symptoms of musculoskeletal damage.Key words: Smartphone, Musculoskeletal symptoms, Prevent 相似文献