Publications by authors named "T Christine E Alvarez"

191 Publications

Topological Aberrance of Structural Brain Network Provides Quantitative Substrates of post-Traumatic Brain Injury Attention Deficits in Children.

Brain Connect 2021 Mar 26. Epub 2021 Mar 26.

New Jersey Institute of Technology, 5965, Biomedical Engineering, 323 Martin Luther King Blvd, Newark, New Jersey, United States, 07102-1982;

Traumatic brain injury (TBI)-induced attention deficits are among the most common long-term cognitive consequences in children. Most of the existing studies attempting to understand the neuropathological underpinnings of cognitive and behavioral impairments in TBI have utilized heterogeneous samples and resulted in inconsistent findings. The current research proposed to investigate topological properties of the structural brain network in children with TBI and their relationship with post-TBI attention problems in a more homogeneous subgroup of children who had severe post-TBI attention deficits (TBI-A). A total of 31 children with TBI-A and 35 group-matched controls were involved in the study. Diffusion tensor imaging-based probabilistic tractography and graph theoretical techniques were used to construct the structural brain network in each subject. Network topological properties were calculated in both global level and regional (nodal) level. Between-group comparisons among the topological network measures and analyses for searching brain-behavioral were all corrected for multiple comparisons using Bonferroni method. Compared to controls, the TBI-A group showed significantly higher nodal local efficiency and nodal clustering coefficient in left inferior frontal gyrus and right transverse temporal gyrus, while significantly lower nodal clustering coefficient in left supramarginal gyrus as well as lower nodal local efficiency in left parahippocampal gyrus. The temporal lobe topological alterations were significantly associated with the post-TBI inattentive and hyperactive symptoms in the TBI-A group. The results suggest that TBI-related structural re-modularity in the WM subnetworks associated with temporal lobe may play a critical role in the onset of severe post-TBI attention deficits in children. These findings provide valuable input for understanding the neurobiological substrates of TBI-A, and have the potential to serve as quantitatively measurable criteria guiding the development of more timely and tailored strategies for diagnoses and treatments to the affected individuals.
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http://dx.doi.org/10.1089/brain.2020.0866DOI Listing
March 2021

Underlying neurological mechanisms associated with symptomatic convergence insufficiency.

Sci Rep 2021 Mar 22;11(1):6545. Epub 2021 Mar 22.

Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, USA.

Convergence insufficiency (CI) is the most common binocular vision problem, associated with blurred/double vision, headaches, and sore eyes that are exacerbated when doing prolonged near work, such as reading. The Convergence Insufficiency Neuro-mechanism Adult Population Study (NCT03593031) investigates the mechanistic neural differences between 50 binocularly normal controls (BNC) and 50 symptomatic CI participants by examining the fast and slow fusional disparity vergence systems. The fast fusional system is preprogrammed and is assessed with convergence peak velocity. The slow fusional system optimizes vergence effort and is assessed by measuring the phoria adaptation magnitude and rate. For the fast fusional system, significant differences are observed between the BNC and CI groups for convergence peak velocity, final position amplitude, and functional imaging activity within the secondary visual cortex, right cuneus, and oculomotor vermis. For the slow fusional system, the phoria adaptation magnitude and rate, and the medial cuneus functional activity, are significantly different between the groups. Significant correlations are observed between vergence peak velocity and right cuneus functional activity (p = 0.002) and the rate of phoria adaptation and medial cuneus functional activity (p = 0.02). These results map the brain-behavior of vergence. Future therapeutic interventions may consider implementing procedures that increase cuneus activity for this debilitating disorder.
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http://dx.doi.org/10.1038/s41598-021-86171-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7985149PMC
March 2021

Relationship Between Age and Cerebral Hemodynamic Response to Breath Holding: A Functional Near-Infrared Spectroscopy Study.

Brain Topogr 2021 Mar 5;34(2):154-166. Epub 2021 Feb 5.

Department of Biomedical Engineering, New Jersey Institute of Technology, Fenster Hall 607, 323 Dr.MLK Jr. Blvd, Newark, NJ, 07102, USA.

Cerebrovascular reactivity (CVR) is routinely measured as a predictor of stroke in people with a high risk of ischemic attack. Neuroimaging techniques such as emission tomography, magnetic resonance imaging, and transcranial doppler are frequently used to measure CVR even though each technique has its limitations. Functional near-infrared spectroscopy (fNIRS), also based on the principle of neurovascular coupling, is relatively inexpensive, portable, and allows for the quantification of oxy- and deoxy-hemoglobin concentration changes at a high temporal resolution. This study examines the relationship between age and CVR using fNIRS in 45 young healthy adult participants aged 18-41 years (6 females, 26.64 ± 5.49 years) performing a simple breath holding task. Eighteen of the 45 participants were scanned again after a week to evaluate the feasibility of fNIRS in reliably measuring CVR. Results indicate (a) a negative relationship between age and hemodynamic measures of breath holding task in the sensorimotor cortex of 45 individuals and (b) widespread positive coactivation within medial sensorimotor regions and between medial sensorimotor regions with supplementary motor area and prefrontal cortex during breath holding with increasing age. The intraclass correlation coefficient (ICC) indicated only a low to fair/good reliability of the breath hold hemodynamic measures from sensorimotor and prefrontal cortices. However, the average hemodynamic response to breath holding from the two sessions were found to be temporally and spatially in correspondence. Future improvements in the sensitivity and reliability of fNIRS metrics could facilitate fNIRS-based assessment of cerebrovascular function as a potential clinical tool.
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http://dx.doi.org/10.1007/s10548-021-00818-4DOI Listing
March 2021

Negative Fusional Vergence Is Abnormal in Children with Symptomatic Convergence Insufficiency.

Optom Vis Sci 2021 Jan;98(1):32-40

Nova Southeastern University, College of Optometry, Ft. Lauderdale, Florida.

Significance: Deficits of disparity divergence found with objective eye movement recordings may not be apparent with standard clinical measures of negative fusional vergence (NFV) in children with symptomatic convergence insufficiency.

Purpose: This study aimed to determine whether NFV is normal in untreated children with symptomatic convergence insufficiency and whether NFV improves after vergence/accommodative therapy.

Methods: This secondary analysis of NFV measures before and after office-based vergence/accommodative therapy reports changes in (1) objective eye movement recording responses to 4° disparity divergence step stimuli from 12 children with symptomatic convergence insufficiency compared with 10 children with normal binocular vision (NBV) and (2) clinical NFV measures in 580 children successfully treated in three Convergence Insufficiency Treatment Trial studies.

Results: At baseline, the Convergence Insufficiency Treatment Trial cohort's mean NFV break (14.6 ± 4.8Δ) and recovery (10.6 ± 4.2Δ) values were significantly greater (P < .001) than normative values. The post-therapy mean improvements for blur, break, and recovery of 5.2, 7.2, and 1.3Δ, respectively, were statistically significant (P < .0001). Mean pre-therapy responses to 4° disparity divergence step stimuli were worse in the convergence insufficiency group compared with the NBV group for peak velocity (P < .001), time to peak velocity (P = .01), and response amplitude (P < .001). After therapy, the convergence insufficiency group showed statistically significant improvements in mean peak velocity (11.63°/s; 95% confidence interval [CI], 6.6 to 16.62°/s), time to peak velocity (-0.12 seconds; 95% CI, -0.19 to -0.05 seconds), and response amplitude (1.47°; 95% CI, 0.83 to 2.11°), with measures no longer statistically different from the NBV cohort (P > .05).

Conclusions: Despite clinical NFV measurements that seem greater than normal, children with symptomatic convergence insufficiency may have deficient NFV when measured with objective eye movement recordings. Both objective and clinical measures of NFV can be improved with vergence/accommodative therapy.
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http://dx.doi.org/10.1097/OPX.0000000000001626DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7789288PMC
January 2021

Structural and functional connectivity mapping of the human corpus callosum organization with white-matter functional networks.

Neuroimage 2021 02 15;227:117642. Epub 2020 Dec 15.

The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China; Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA. Electronic address:

The corpus callosum serves as a crucial organization for understanding the information integration between the two hemispheres. Our previous study explored the functional connectivity between the corpus callosum and white-matter functional networks (WM-FNs), but the corresponding physical connectivity remains unknown. The current study uses the resting-state fMRI of Human Connectome Project data to identify ten WM-FNs in 108 healthy subjects, and then independently maps the structural and functional connectivity between the corpus callosum and above WM-FNs using the diffusion tensor images (DTI) tractography and resting-state functional connectivity (RSFC). Our results demonstrated that the structural and functional connectivity between the human corpus callosum and WM-FNs have the following high overall correspondence: orbitofrontal WM-FN, DTI map = 89% and RSFC map = 92%; sensorimotor middle WM-FN, DTI map = 47% and RSFC map = 77%; deep WM-FN, DTI map = 50% and RSFC map = 79%; posterior corona radiata WM-FN, DTI map = 82% and RSFC map = 73%. These findings reinforce the notion that the corpus callosum has unique spatial distribution patterns connecting to distinct WM-FNs. However, important differences between the structural and functional connectivity mapping results were also observed, which demonstrated a synergy between DTI tractography and RSFC toward better understanding the information integration of primary and higher-order functional systems in the human brain.
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http://dx.doi.org/10.1016/j.neuroimage.2020.117642DOI Listing
February 2021

The Contributions of Immigrant Nurses in the U.S. During the COVID-19 Pandemic: A CGFNS International Study.

Nurse Lead 2020 Dec 1. Epub 2020 Dec 1.

Research Associate to the President and CEO, CGFNS International, Inc. 3600 Market Street, Suite 400, Philadelphia, PA 19104.

No other event has put healthcare - and nursing - at the forefront of local, national, and global discussions in the same way as the COVID-19 pandemic. Studies suggest that immigrant nurses are a critical part of U.S. healthcare and we are increasingly reliant on the skills they bring and the care they provide. To quantify and qualify this contribution, CGFNS International designed a data-collection survey and distributed to nearly 74,000 foreign-educated healthcare professionals currently practicing in the United States during the COVID-19 pandemic. While some challenges were reported, most nurses surveyed reported working with patients diagnosed with COVID-19 and having access to adequate PPE, and many felt the public perception of nurses has improved since the beginning of the pandemic. Continued research on the experiences of immigrant nurses during ongoing global pandemic response and beyond could provide more comprehensive information on the immigrant nurses that drive the U.S. health system.
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http://dx.doi.org/10.1016/j.mnl.2020.11.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7705416PMC
December 2020

Convergence Insufficiency Neuro-mechanism in Adult Population Study Randomized Clinical Trial: Clinical Outcome Results.

Optom Vis Sci 2020 12;97(12):1061-1069

Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey.

Significance: These data confirm the effectiveness of office-based vergence/accommodative therapy for improving the near point of convergence and positive fusional vergence in young adults with symptomatic convergence insufficiency within a double-masked longitudinal randomized clinical trial.

Purpose: This study aimed to report changes in clinical signs and symptoms of convergence insufficiency from a randomized clinical trial evaluating the effectiveness of office-based vergence/accommodative therapy for young adults with symptomatic convergence insufficiency.

Methods: In this double-masked, randomized clinical trial, convergence insufficiency patients (n = 50; average age, 21 ± 3 years; range, 18 to 32 years) were randomized to either office-based vergence/accommodative therapy or office-based placebo therapy. Improvements in (1) near point of convergence, (2) positive fusional vergence, and (3) self-reported symptoms (Convergence Insufficiency Symptom Survey [CISS] score) were evaluated after twelve 1-hour sessions of treatment within the office comparing the results from the vergence/accommodative therapy and the placebo therapy groups.

Results: The mean near point of convergence improved by 6.0 and 3.1 cm in the vergence/accommodative and placebo therapy groups, respectively (mean difference of -2.9 cm; 95% confidence interval [CI], -4.6 to -1.0 cm; P < .01). The mean positive fusional vergence increased by 17.3 and 7.4Δ in the vergence/accommodative and placebo therapy groups, respectively (mean difference of 9.9Δ; 95% CI, 4.9 to 16.0Δ; P < .001). The mean CISS score improved by 12.4 and 10.1 points in the vergence/accommodative and placebo therapy groups, respectively (mean difference of 2.3 points; 95% CI, -8.3 to +4.6 points; P = .56).

Conclusions: Our results demonstrate that office-based vergence/accommodative therapy is effective for improving the near point of convergence and positive fusional vergence in young adults with symptomatic convergence insufficiency. However, given that both treatment groups had a similar reduction in self-reported symptoms, we recommend that the CISS be revised if it is to be used as an outcome measure in future studies of convergence insufficiency.
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http://dx.doi.org/10.1097/OPX.0000000000001606DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7744390PMC
December 2020

Winter movement patterns of a globally endangered avian scavenger in south-western Europe.

Sci Rep 2020 10 19;10(1):17690. Epub 2020 Oct 19.

Movement Ecology Lab, Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, C/ Catedrático José Beltrán 2, 46980, Paterna, Valencia, Spain.

Partial migration, whereby some individuals migrate and some do not, is relatively common and widespread among animals. Switching between migration tactics (from migratory to resident or vice versa) occurs at individual and population levels. Here, we describe for the first time the movement ecology of the largest wintering population of Egyptian Vultures (Neophron percnopterus) in south-west Europe. We combined field surveys and GPS tracking data from December to February during four wintering seasons (2014-2018). The wintering population consisted on average of 85 individuals (range 58-121; 76% adults and 24% subadults). Individuals were counted at five different roosting sites located near farms, unauthorized carcass deposition sites and authorized carcass deposition sites. Our results show that vultures tend to remain close to the roosting site. Moreover, we observed that females exhibited smaller home range sizes than males, which suggests a possible differential use of food sources. Overall, birds relied more on farms than other available food resources, particularly subadult individuals which exploited more intensively these sites. Our results showed that Egyptian Vultures congregate in significant numbers at specific sites throughout the winter period in south-west Spain and that these roosting and feeding sites should be given some level of legal protection and regular monitoring. Furthermore, predictable food sources might be driving the apparent increase in the non-migratory population of Egyptian Vultures, as observed in other avian species which are also changing their migratory behavior.
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http://dx.doi.org/10.1038/s41598-020-74333-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7572415PMC
October 2020

Prevalence of ICU Delirium in Postoperative Pediatric Cardiac Surgery Patients.

Pediatr Crit Care Med 2021 Jan;22(1):68-78

University of California San Francisco, School of Nursing, San Francisco, CA.

Objectives: The objective of this study was to determine the prevalence of ICU delirium in children less than 18 years old that underwent cardiac surgery within the last 30 days. The secondary aim of the study was to identify risk factors associated with ICU delirium in postoperative pediatric cardiac surgical patients.

Design: A 1-day, multicenter point-prevalence study of delirium in pediatric postoperative cardiac surgery patients.

Setting: Twenty-seven pediatric cardiac and general critical care units caring for postoperative pediatric cardiac surgery patients in North America.

Patients: All children less than 18 years old hospitalized in the cardiac critical care units at 06:00 on a randomly selected, study day.

Interventions: Eligible children were screened for delirium using the Cornell Assessment of Pediatric Delirium by the study team in collaboration with the bedside nurse.

Measurement And Main Results: Overall, 181 patients were enrolled and 40% (n = 73) screened positive for delirium. There were no statistically significant differences in patient demographic information, severity of defect or surgical procedure, past medical history, or postoperative day between patients screening positive or negative for delirium. Our bivariate analysis found those patients screening positive had a longer duration of mechanical ventilation (12.8 vs 5.1 d; p = 0.02); required more vasoactive support (55% vs 26%; p = 0.0009); and had a higher number of invasive catheters (4 vs 3 catheters; p = 0.001). Delirium-positive patients received more total opioid exposure (1.80 vs 0.36 mg/kg/d of morphine equivalents; p < 0.001), did not have an ambulation or physical therapy schedule (p = 0.02), had not been out of bed in the previous 24 hours (p < 0.0002), and parents were not at the bedside at time of data collection (p = 0.008). In the mixed-effects logistic regression analysis of modifiable risk factors, the following variables were associated with a positive delirium screen: 1) pain score, per point increase (odds ratio, 1.3; 1.06-1.60); 2) total opioid exposure, per mg/kg/d increase (odds ratio, 1.35; 1.06-1.73); 3) SBS less than 0 (odds ratio, 4.01; 1.21-13.27); 4) pain medication or sedative administered in the previous 4 hours (odds ratio, 3.49; 1.32-9.28); 5) no progressive physical therapy or ambulation schedule in their medical record (odds ratio, 4.40; 1.41-13.68); and 6) parents not at bedside at time of data collection (odds ratio, 2.31; 1.01-5.31).

Conclusions: We found delirium to be a common problem after cardiac surgery with several important modifiable risk factors.
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http://dx.doi.org/10.1097/PCC.0000000000002591DOI Listing
January 2021

Test-retest of a phoria adaptation stimulus-induced functional MRI experiment.

J Vis 2020 08;20(8):17

Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, USA.

This study was designed to identify the neural substrates activated during a phoria adaptation task using functional magnetic resonance imaging (MRI) in young adults with normal binocular vision and to test the repeatability of the fMRI measurements for this protocol. The phoria adaptation task consisted of a block protocol of 90 seconds of near visual crossed fixation followed by 90 seconds of far visual uncrossed fixation, repeated three times; the data were collected during two different experimental sessions. Results showed that the oculomotor vermis, cuneus, and primary visual cortex had the greatest functional activity within the regions of interest studied when stimulated by the phoria adaptation task. The oculomotor vermis functional activity had an intraclass correlation coefficient (ICC) of 0.3, whereas the bilateral cuneus and primary visual cortex had good ICC results of greater than 0.6. These results suggest that the sustained visual fixation task described within this study reliably activates the neural substrates of phoria adaptation. This protocol establishes a methodology that can be used in future longitudinal studies investigating therapeutic interventions that may modify phoria adaptation.
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http://dx.doi.org/10.1167/jov.20.8.17DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7438664PMC
August 2020

A Normative Study of Objective Measures of Disparity Vergence and Saccades in Children 9 to 17 Years Old.

Optom Vis Sci 2020 Jun;97(6):416-423

Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey.

Significance: This study establishes normative data for objective outcome measures of vergence and saccade eye movements for the pediatric population. These data should facilitate future clinical trial design.

Purpose: This study was designed to establish normative data for objective measures of disparity vergence and saccades in children between the ages 9 and 17 years using an objective binocular eye movement tracking system.

Methods: Participants (aged 9 to 17 years) had a vision examination including refraction, accommodative, and binocular vision testing. Eligibility criteria included 20/25 visual acuity with best correction, normal accommodation, and binocular vision. The ISCAN RK-826PCI binocular tracking system (ISCAN, Woburn, MA) was used to objectively record horizontal, symmetrical disparity vergence, and saccadic eye movements. Parameters assessed included peak velocity, time to peak velocity, latency, and response amplitude for both disparity vergence and saccades.

Results: One hundred eighteen participants were recruited (54.94% female; mean age, 13.5 years), and 77.1% (91/118) of the participants completed the assessment with usable data. A sample of the normative data included peak velocity (°/s), which had a mean ± standard deviation of 25.4 ± 2.9, 22.0 ± 3.0, 225 ± 16.7, and 332.5 ± 20.5 for 4° convergence, 4° divergence, 5° saccades, and 10° saccades, respectively. The mean ± standard deviation for the latency (seconds) measures were 0.28 ± 0.1, 0.28 ± 0.16, 0.23 ± 0.05, and 0.23 ± 0.05 for 4° convergence, 4° divergence, 5° saccades, and 10° saccades, respectively.

Conclusions: Normative data enable researchers to have benchmark results for comparison with patient populations with binocular dysfunction. These objective disparity vergence measures can serve as outcome measures in future clinical trials to assess the effectiveness of therapeutic interventions by determining whether post-treatment results are similar to normal data.
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http://dx.doi.org/10.1097/OPX.0000000000001515DOI Listing
June 2020

Comparison of quick SOFA and SIRS scales at the bedside of patients with Staphylococcus aureus bacteremia

Biomedica 2020 05 1;40(Supl. 1):125-131. Epub 2020 May 1.

Grupo de Investigación en Medicina interna, Universidad Tecnológica de Pereira, Pereira, Colombia.

Introduction: One of the primary causes of community-acquired bacteremia also associated with nosocomial infections is Staphylococcus aureus, which is responsible for a high percentage of complications leading to high morbidity and mortality rates. The systemic inflammatory response syndrome (SIRS) criteria have been traditionally used to evaluate the presence of sepsis; however, recent evidence questions its predictive value due to its low sensitivity and specificity. In 2016, new criteria for sepsis were published and a new tool emerged, quick SOFA (qSOFA), for the rapid evaluation of infection in emergency services. Objective: To compare the qSOFA and SRIS tools for the prediction of bacteremia caused by S. aureus. Materials and methods: We conducted an observational study in patients with S. aureus bacteremia to evaluate their phenotypic resistance patterns, some special features (sociodemographic characteristics, clinical and paraclinical values), complications, and mortality. The results of the qSOFA and SIRS scales were analyzed to identify which of them could better predict the presence of S. aureus bacteremia. Results: Twenty-six bacteremic patients were identified. Staphylococcus aureus was the second most frequently isolated bacteria. The results evidenced a mortality rate of 50% (13 cases) and a prevalence of 30% of MRSA. For the clinical scores evaluated, the qSOFA scale was positive in 30.8% of the patients, and the SIRS scale, in 92.3%. Discussion: The mortality rate for the population under study was high and the qSOFA tool had a lower diagnostic yield compared to the classic criteria for SIRS.
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http://dx.doi.org/10.7705/biomedica.4943DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7449100PMC
May 2020

Dynamics of the Disparity Vergence Fusion Sustain Component.

J Eye Mov Res 2019 Oct 4;12(4). Epub 2019 Dec 4.

New Jersey Institute of Technology, Newark, NJ, USA.

The stereotypical vergence response to a step stimulus consists of two dynamic components: a high velocity fusion initiating component followed by a slower component that may mediate sustained fusion. The initial component has been well-studied and is thought to be controlled by an open-loop mechanism. Less is known about the slow, or fusion sustaining component except that it must be feedback controlled to achieve the positional precision of sustained fusion. Given the delays in disparity vergence control, a feedback control system is likely to exhibit oscillatory behavior. Vergence responses to 4 deg step changes in target position were recorded in eight subjects. The slow component of each response was isolated manually using interactive graphics and the frequency spectrum determined. The frequency spectra of all isolated slow vergence movements showed a large low frequency peak between 1.0 and 2.0 Hz and one or more higher frequency components. The higher frequency components were found to be harmonics of the low frequency oscillation. A feedback model of the slow component was developed consisting of a time delay, an integral/derivative controller and an oculomotor plant based on Robinson's model. Model simulations showed that a direction dependent asymmetry in the derivative element was primarily responsible for the higher frequency harmonic components. Simulations also showed that the base frequencies are primarily dependent on the time delay in the feedback control system. The fact that oscillatory behavior was found in all subjects provides strong support that the slow, fusion sustaining component is mediated by a feedback system.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7173722PMC
October 2019

Target Eccentricity and Form Influences Disparity Vergence Eye Movements Responses: A Temporal and Dynamic Analysis.

J Eye Mov Res 2019 Oct 9;12(4). Epub 2019 Dec 9.

New Jersey Institute of Technology, Newark, NJ, USA.

This study sought to investigate whether stimulation to the fovea or the parafovea with different color combinations influenced the temporal and dynamic features of 4° disparity vergence step responses. Twelve unique types of stimuli were displayed within a haploscope presented along the participant's midsagittal plane. Vergence eye movement responses from fifteen naïve participants were recorded using video-based infrared eye tracking instrumentation. Latency and peak velocity from left and right eye movement responses were quantified. Results show that the type of stimulus projection (foveal versus parafoveal) significantly (<0.001) influences the vergence response latency but did not impact peak velocity. Vergence responses to eccentric circles with 6° eccentricity targeting the parafovea resulted in a significantly faster response latency compared to vergence responses to a cross with 2° eccentricity stimuli targeting the fovea. Results have implications for the stimulus design of a variety of applications from virtual reality to vision therapy interventions.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7079726PMC
October 2019

Changes in the Disparity Vergence Main Sequence after Treatment of Symptomatic Convergence Insufficiency in Children.

J Eye Mov Res 2019 Oct 4;12(4). Epub 2019 Dec 4.

New Jersey Institute of Technology, Newark, NJ, USA.

This study investigates the underlying physiological mechanisms that may lead to improved outcomes for symptomatic convergence insufficiency (Cl) patients after 12 weeks of office-based vergence/accommodation therapy (OBVAT) by evaluating the change in the main sequence of vergence and saccadic eye movements. In this prospective trial, 12 participants with symptomatic Cl were recruited and treated with 12 weeks of OBVAT. Outcome measures included the objective assessment of the following: peak velocity, time to peak velocity, latency, response amplitude, and clinical changes in the near point of convergence (NPC), positive fusional vergence (PFV) and symptoms via the Convergence Insufficiency Symptom Survey (CISS). Ten of the twelve participants (83%) were categorized as "successful" and two were "improved" based on pre-determined published criteria (CISS, NPC, PFV). There were statistically significant changes in peak velocity, time to peak velocity, and response amplitude for both 4° and 6° symmetrical convergence and divergence eye movements. There was a significant change in the main sequence ratio for convergence post-OBVAT compared to baseline measurements (P=0.007) but not for divergence or saccadic responses. Phasic/step vergence movements adjust the underlying neural control of convergence and are critical within a vision therapy program for Cl patients.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7079725PMC
October 2019

Multimodal neuroimaging-based prediction of adult outcomes in childhood-onset ADHD using ensemble learning techniques.

Neuroimage Clin 2020 7;26:102238. Epub 2020 Mar 7.

Department of Biomedical Engineering, New Jersey Institute of Technology, NJ, USA; Department of Electrical and Computer Engineering, New Jersey Institute of Technology, NJ, USA. Electronic address:

Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent and heterogeneous neurodevelopmental disorder, which is diagnosed using subjective symptom reports. Machine learning classifiers have been utilized to assist in the development of neuroimaging-based biomarkers for objective diagnosis of ADHD. However, existing basic model-based studies in ADHD report suboptimal classification performances and inconclusive results, mainly due to the limited flexibility for each type of basic classifier to appropriately handle multi-dimensional source features with varying properties. This study applied ensemble learning techniques (ELTs), a meta-algorithm that combine several basic machine learning models into one predictive model in order to decrease variance, bias, or improve predictions, in multimodal neuroimaging data collected from 72 young adults, including 36 probands (18 remitters and 18 persisters of childhood ADHD) and 36 group-matched controls. All currently available optimization strategies for ELTs (i.e., voting, bagging, boosting and stacking techniques) were tested in a pool of semifinal classification results generated by seven basic classifiers. The high-dimensional neuroimaging features for classification included regional cortical gray matter (GM) thickness and surface area, GM volume of subcortical structures, volume and fractional anisotropy of major white matter fiber tracts, pair-wise regional connectivity and global/nodal topological properties of the functional brain network for cue-evoked attention process. As a result, the bagging-based ELT with the base model of support vector machine achieved the best results, with significant improvement of the area under the receiver of operating characteristic curve (0.89 for ADHD vs. controls and 0.9 for ADHD persisters vs. remitters). Features of nodal efficiency in right inferior frontal gyrus, right middle frontal (MFG)-inferior parietal (IPL) functional connectivity, and right amygdala volume significantly contributed to accurate discrimination between ADHD probands and controls; higher nodal efficiency of right MFG greatly contributed to inattentive and hyperactive/impulsive symptom remission, while higher right MFG-IPL functional connectivity strongly linked to symptom persistence in adults with childhood ADHD. Considering their improved robustness than the commonly implemented basic classifiers, findings suggest that ELTs may have the potential to identify more reliable neurobiological markers for neurodevelopmental disorders.
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http://dx.doi.org/10.1016/j.nicl.2020.102238DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7076568PMC
February 2021

The Organization of the Human Corpus Callosum Estimated by Intrinsic Functional Connectivity with White-Matter Functional Networks.

Cereb Cortex 2020 05;30(5):3313-3324

The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Laboratory for Neuroinformation, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, China.

The corpus callosum is the commissural bridge of white-matter bundles important for the human brain functions. Previous studies have analyzed the structural links between cortical gray-matter networks and subregions of corpus callosum. While meaningful white-matter functional networks (WM-FNs) were recently reported, how these networks functionally link with distinct subregions of corpus callosum remained unknown. The current study used resting-state functional magnetic resonance imaging of the Human Connectome Project test-retest data to identify 10 cerebral WM-FNs in 119 healthy subjects and then parcellated the corpus callosum into distinct subregions based on the functional connectivity between each callosal voxel and above networks. Our results demonstrated the reproducible identification of WM-FNs and their links with known gray-matter functional networks across two runs. Furthermore, we identified reliably parcellated subregions of the corpus callosum, which might be involved in primary and higher order functional systems by functionally connecting with WM-FNs. The current study extended our knowledge about the white-matter functional signals to the intrinsic functional organization of human corpus callosum, which could help researchers understand the neural substrates underlying normal interhemispheric functional connectivity as well as dysfunctions in various mental disorders.
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http://dx.doi.org/10.1093/cercor/bhz311DOI Listing
May 2020

Reliability of Frontal Eye Fields Activation and Very Low-Frequency Oscillations Observed during Vergence Eye Movements: an fNIRS Study.

Sci Rep 2020 01 20;10(1):712. Epub 2020 Jan 20.

Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, USA.

Functional near-infrared spectroscopy (fNIRS), an imaging tool that utilizes infrared light to measure changes within the concentration of oxygenated (HbO) and deoxygenated (HbR) hemoglobin, holds promise to study functional activity from motor, visual, and memory cortical regions using stimulus-induced tasks. This study investigated the reliability for fNIRS to examine cortical activations within the frontal eye fields (FEF) while initiating vergence eye movements, the inward and outward rotation of the eyes. FNIRS data were collected from twenty participants with normal binocular vision while performing vergence eye movements compared to sustained gaze fixation within a block design during two different sessions. Reliability of the experimental protocol was assessed using the intraclass correlation coefficient (ICC). The ICC values ranged from 0.6 to 0.7 for measuring the HbO activation within the vicinity of the FEF. A frequency power spectrum analysis revealed two predominant frequencies within the functional activation signals from the FEF. One high-intensity signal was present at 0.029 Hz, centering around the block design frequency. The peak-intensity signal was observed between 0.012 and 0.018 Hz where this very low-frequency oscillation (VLFO) was hypothesized to be generated by the macrovasculature present near the FEF and should be avoided as a block design frequency in future fNIRS studies to avoid false positive results.
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http://dx.doi.org/10.1038/s41598-020-57597-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6971237PMC
January 2020

Clinical and Functional Imaging Changes Induced from Vision Therapy in Patients with Convergence Insufficiency.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:104-109

Office-Based Vergence/Accommodative Therapy (OBVAT) is an effective treatment for convergence insufficiency (CI) and remediates symptoms in about 75% of patients. Hence, the study of CI patients can serve as a systems-level model to understand the neural mechanisms evoked from rehabilitation. Symptomatic young adult CI patients (N=25) participated in 12 hours of OBVAT and were compared to 25 binocularly normal controls (BNC) using unpaired t-tests. CI patients have significantly lower near point of convergence and positive fusional vergence and were more symptomatic compared to BNC (p<; 0.0001). Using paired t-tests, significant differences (p<; 0.0001) were observed between CI patients' baseline and post-OBVAT measurements where the near point of convergence decreased, positive fusional vergence increased, and the results from the Convergence Insufficiency Symptom Survey (CISS) decreased. Using paired t-tests, the mean beta weights of the functional activity significantly increased for the frontal eye fields (p<; 0.01) and the oculomotor vermis (p<; 0.05) for CI patients post-OBVAT compared to baseline measurements. These data demonstrate that OBVAT increases functional activity within the brain and improves clinical function and visual symptoms in CI patients.
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http://dx.doi.org/10.1109/EMBC.2019.8857163DOI Listing
July 2019

Resting-State Functional Connectivity of the Thalamus in Complete Spinal Cord Injury.

Neurorehabil Neural Repair 2020 02 6;34(2):122-133. Epub 2020 Jan 6.

New Jersey Institute of Technology, Newark, NJ, USA.

. Neuroimaging studies of spinal cord injury (SCI) have mostly examined the functional organization of the cortex, with only limited focus on the subcortical substrates of the injury. However, thalamus is an important modulator and sensory relay that requires investigation at a subnuclei level to gain insight into the neuroplasticity following SCI. . To use resting-state functional magnetic resonance imaging to examine the functional connectivity (FC) of thalamic subnuclei in complete SCI patients. . A seed-based connectivity analysis was applied for 3 thalamic subnuclei: pulvinar, mediodorsal, and ventrolateral nucleus in each hemisphere. A nonparametric 2-sample test with permutations was applied for each of the 6 thalamic seeds to compute FC differences between 22 healthy controls and 19 complete SCI patients with paraplegia. . Connectivity analysis showed a decrease in the FC of the bilateral mediodorsal nucleus with right superior temporal gyrus and anterior cingulate cortex in the SCI group. Similarly, the left ventrolateral nucleus exhibited decreased FC with left superior temporal gyrus in SCI group. In contrast, left pulvinar nucleus demonstrated an increase in FC with left inferior frontal gyrus and left inferior parietal lobule in SCI group. Our findings also indicate a negative relationship between postinjury durations and thalamic FC to regions of sensorimotor and visual cortices, where longer postinjury durations (~12 months) is associated with higher negative connectivity between these regions. . This study provides evidence for reorganization in the thalamocortical connections known to be involved in multisensory integration and affective processing, with possible implications in the generation of sensory abnormalities after SCI.
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http://dx.doi.org/10.1177/1545968319893299DOI Listing
February 2020

CE: Original Research: The Recruitment Experience of Foreign-Educated Health Professionals to the United States.

Am J Nurs 2020 01;120(1):28-38

Franklin A. Shaffer is president and chief executive officer of CGFNS International, Inc., in Philadelphia. He is also a member of AJN's international advisory board. Mukul A. Bakhshi is director of the Alliance for Ethical International Recruitment Practices and of Government Affairs, both at CGFNS International. Niamh Farrell is an international research associate and Thomas D. Álvarez is a research associate to the president and chief executive officer of CGFNS International. Contact author: Franklin A. Shaffer, The authors and planners have disclosed no potential conflicts of interest, financial or otherwise. A podcast with the authors is available at www.ajnonline.com.

Background: In 2007 AcademyHealth published a landmark report on the U.S.-based international nurse recruitment industry. This article provides an update to that report, describing the current state of recruitment of foreign-educated health professionals (FEHPs), in particular foreign-educated nurses (FENs), to the United States. Areas covered include the regulatory landscape, economic issues, recruitment industry changes, and current demographic and migration trends.

Purpose: To learn more, CGFNS International, Inc., formerly known as the Commission on Graduates of Foreign Nursing Schools, and its Alliance for Ethical International Recruitment Practices division conducted a study designed to elicit qualitative and quantitative data that would further illuminate the recruitment experience.

Methods: Researchers conducted a survey of FEHPs, recruited from those who used VisaScreen services between 2015 and 2017, designed to assess their recruitment experiences. They also conducted interviews with a smaller sample of FENs and recruiters to elicit greater detail.

Results: While there was evidence of progress relative to the ethical recruitment of FEHPs, issues such as high breach fees, inadequate orientation, and misalignment of expectations regarding work environment and location were also revealed.

Conclusion: Given that FEHP migration to the United States is likely to continue its upward trajectory, better strategies to implement market-wide practices that ensure the safe, orderly, and ethical recruitment of FEHPs are needed.
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http://dx.doi.org/10.1097/01.NAJ.0000652024.67027.f7DOI Listing
January 2020

Test-Retest Reliability of Functional Magnetic Resonance Imaging Activation for a Vergence Eye Movement Task.

Neurosci Bull 2020 May 23;36(5):506-518. Epub 2019 Dec 23.

Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ, 07102, USA.

Vergence eye movements are the inward and outward rotation of the eyes responsible for binocular coordination. While studies have mapped and investigated the neural substrates of vergence, it is not well understood whether vergence eye movements evoke the blood oxygen level-dependent signal reliably in separate experimental visits. The test-retest reliability of stimulus-induced vergence eye movement tasks during a functional magnetic resonance imaging (fMRI) experiment is important for future randomized clinical trials (RCTs). In this study, we established region of interest (ROI) masks for the vergence neural circuit. Twenty-seven binocularly normal young adults participated in two functional imaging sessions measured on different days on the same 3T Siemens scanner. The fMRI experiments used a block design of sustained visual fixation and rest blocks interleaved between task blocks that stimulated eight or four vergence eye movements. The test-retest reliability of task-activation was assessed using the intraclass correlation coefficient (ICC), and that of spatial extent was assessed using the Dice coefficient. Functional activation during the vergence eye movement task of eight movements compared to rest was repeatable within the primary visual cortex (ICC = 0.8), parietal eye fields (ICC = 0.6), supplementary eye field (ICC = 0.5), frontal eye fields (ICC = 0.5), and oculomotor vermis (ICC = 0.6). The results demonstrate significant test-retest reliability in the ROIs of the vergence neural substrates for functional activation magnitude and spatial extent using the stimulus protocol of a task block stimulating eight vergence eye movements compared to sustained fixation. These ROIs can be used in future longitudinal RCTs to study patient populations with vergence dysfunctions.
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http://dx.doi.org/10.1007/s12264-019-00455-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7186292PMC
May 2020

The Convergence Insufficiency Neuro-mechanism in Adult Population Study (CINAPS) Randomized Clinical Trial: Design, Methods, and Clinical Data.

Ophthalmic Epidemiol 2020 02 22;27(1):52-72. Epub 2019 Oct 22.

Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, USA.

: To describe the design and methodology of the Convergence Insufficiency Neuro-mechanism in Adult Population Study (CINAPS), the first randomized clinical trial (RCT) studying young adults with symptomatic convergence insufficiency (CI) using a combination of traditional clinical tests, objective eye movement recordings, and functional brain activities as outcome measures.: In this double-masked RCT, binocularly normal controls (BNC) (N = 50) and CI patients (N = 50) are randomized into office-based vergence/accommodative therapy (OBVAT) or office-based placebo therapy (OBPT). Outcome measures included clinical signs and symptoms, phoria adaptation, forced fixation disparity curves, binocular rivalry, vergence and saccadic objective eye movements, and task-induced functional brain activities. This study is registered on ClinicalTrials.gov NCT03593031.: No significant baseline differences are observed between the BNC ( > .4) or CI ( > .3) participants assigned to OBVAT or OBPT for age, near point of convergence (NPC), positive fusional vergence (PFV), phoria at distance and near, amplitude of accommodation, or the Convergence Insufficiency Symptom Survey (CISS). Significant differences are observed between the CI and BNC cohorts at baseline measurements for NPC, PFV, difference in phoria from far to near, amplitude of accommodation, and CISS ( < .001). For the CI patients, 26% had a comorbidity of accommodation insufficiency, and 16% self-reported ADHD.: Features of the study design include the following: standardized diagnostic and office-based therapeutic intervention, placebo treatment arm, masked clinical outcome examinations, objective eye movement recordings, functional imaging, phoria adaptation, fixation disparity curves and binocular rivalry measurements.
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http://dx.doi.org/10.1080/09286586.2019.1679192DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6944764PMC
February 2020

Epidemiology and Incidence of Pediatric Concussions in General Aspects of Life.

Brain Sci 2019 Sep 27;9(10). Epub 2019 Sep 27.

Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA.

Background: Concussions are one of the most common head injuries acquired within the pediatric population. While sport-related concussions are well documented, concussions within other aspects of a child's life are not as well researched. The purpose of this study is to examine the incidence of a large pediatric concussion population in a broad range of daily activities.

Methods: Patients' gender and nature of injury were extracted from 1408 medical records of patients who were diagnosed with a concussion at Saint Peter's Sports Medicine Institute. Statistical analyses were conducted for activities and environmental settings using chi-squared tests.

Results: Concussions were most prevalent in organized sports (53.3%), followed by injuries within the following settings: school (16.5%), recreational (6.7%), motor vehicle collisions (6.6%), home (5.5%), and other (11.3%). Specifically, soccer (12.9%), school physical education (PE) class (10.6%), and football (9.8%) subcategories recorded the most incidences of concussion. For the PE class cohort ( = 149), significantly more females were diagnosed with a concussion compared to males ( < 0.001).

Conclusions: PE-related concussions had the second highest incidence rate after organized sports. A significant gender difference was observed in PE class. Awareness about concussions and methods to reduce the risk of concussion is suggested for PE classes.
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http://dx.doi.org/10.3390/brainsci9100257DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6827131PMC
September 2019

Disrupting Policy and Practice: Refugees Shaping the Future.

Nurs Adm Q 2019 Oct/Dec;43(4):370-373

CGFNS International, Inc, Philadelphia, Pennsylvania (Dr Shaffer and Mr Álvarez); and International Centre on Nurse Migration, CGFNS International, Inc, Philadelphia, Pennsylvania (Mr Sciasci).

For decades, refugee policies on local, national, regional, and international levels have set the narrative surrounding refugees' identities and roles in society. Often, these policies negatively affect refugees and can hinder any effort for successful integration (ie, employment). The focus of this article is to identity how refugees, specifically refugee nurses, are reshaping standard policy practices when it comes to integration and inclusion, as well as economic and social well-being. With an estimated 68.5 million forcibly displaced persons worldwide (25.4 million of which are refugees), it is important to shed light on the importance of including their voices in the dialogue during all stages of the policy development process. They should be included in the dialogue, from agenda setting to evaluation, in order to challenge current beliefs and attitudes. It is critical for societies to recognize refugee nurses' professional qualifications, skills, and abilities in order to address the ongoing shortages of health professionals that many nations are facing today.
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http://dx.doi.org/10.1097/NAQ.0000000000000368DOI Listing
March 2020

Evaluation of laccase production by Ganoderma lucidum in submerged and solid-state fermentation using different inducers.

J Basic Microbiol 2019 Aug 1;59(8):784-791. Epub 2019 Jul 1.

Master Program in Industrial Biotechnology, Universidade Positivo (UP), Curitiba, Paraná, Brazil.

Laccases are multicopper oxidases with high potential for industrial applications. Several basidiomycete fungi are natural producers of this enzyme; however, the optimization of production and selection of inducers for increased productivity coupled with low costs is necessary. Lignocellulosic residues are important lignin sources and potential inducers for laccase production. Pinus taeda, a dominant source of wood-based products, has not been investigated for this purpose yet. The aim of this study was to evaluate the production of laccase by the basidiomycete fungus Ganoderma lucidum in the presence of different inducers in submerged and solid-state fermentation. The results of submerged fermentation in presence of 5 μM CuSO , 2 mM ferulic acid, 0.1 g/L P. taeda sawdust, or 0.05 g/L Kraft lignin indicated that although all the tested inducers promoted increase in laccase activity in specific periods of time, the presence of 2 mM ferulic acid resulted in the highest value of laccase activity (49 U/L). Considering the submerged fermentation, experimental design following the Plackett-Burman method showed that the concentrations of ferulic acid and P. taeda sawdust had a significant influence on the laccase activity. The highest value of 785 U/L of laccase activity on submerged fermentation was obtained on the seventh day of cultivation. Finally, solid-state fermentation cultures in P. taeda using ferulic acid or CuSO as inducers resulted in enzymatic activities of 144.62 and 149.89 U/g, respectively, confirming the potential of this approach for laccase production by G. lucidum.
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http://dx.doi.org/10.1002/jobm.201900084DOI Listing
August 2019

Crystallographic structure and molecular dynamics simulations of the major endoglucanase from Xanthomonas campestris pv. campestris shed light on its oligosaccharide products release pattern.

Int J Biol Macromol 2019 Sep 16;136:493-502. Epub 2019 Jun 16.

Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, SP, Brazil. Electronic address:

Cellulases are essential enzymatic components for the transformation of plant biomass into fuels, renewable materials and green chemicals. Here, we determined the crystal structure, pattern of hydrolysis products release, and conducted molecular dynamics simulations of the major endoglucanase from the Xanthomonas campestris pv. campestris (XccCel5A). XccCel5A has a TIM barrel fold with the catalytic site centrally placed in a binding groove surrounded by aromatic side chains. Molecular dynamics simulations show that productive position of the substrate is secured by a network of hydrogen bonds in the four main subsites, which differ in details from homologous structures. Capillary zone electrophoresis and computational studies reveal XccCel5A can act both as endoglucanase and licheninase, but there are preferable arrangements of substrate regarding β-1,3 and β-1,4 bonds within the binding cleft which are related to the enzymatic efficiency.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.06.107DOI Listing
September 2019

Vergence Endurance Test: A Pilot Study for a Concussion Biomarker.

J Neurotrauma 2019 07 28;36(14):2200-2212. Epub 2019 Mar 28.

1 Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, New Jersey.

The Vergence Endurance Test (VET), a quantitative and objective eye movement assessment, was utilized to differentiate control from concussed subjects. Nine symptomatic concussed (2 male; 30.8 ± 11 years) and 9 asymptomatic control (6 male; 25.1 ± 1.4 years) subjects participated in the VET. Symmetrical disparity vergence step targets were presented with and without visual distractors. A masked data analyst measured vergence latency, peak velocity, response amplitude, settling time, and the percentage of trials which contained blinks. A Binocular Precision Index (BPI) and a Binocular Accuracy Index (BAI) were calculated to quantify the changes that occur in the vergence parameters over the duration of the VET. Convergence and divergence peak velocity, divergence response amplitude, the percentage of trials that contained blinks during the transient portion of the response, and the BAI were significantly ( < 0.05) different between the concussed and the control subjects. For these parameters, the BAI and divergence response amplitude yielded the greatest accuracy, 78%, in their ability to discriminate between the groups. The VET objectively measures the change in vergence performance over time and shows promise as a method to diagnose a concussion. Future studies will determine whether the VET can be used to assess the extent of natural recovery and the effectiveness of therapeutic interventions.
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http://dx.doi.org/10.1089/neu.2018.6075DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6653808PMC
July 2019

Perinatal diagnosis and management of early-onset Marfan syndrome: case report and systematic review.

J Matern Fetal Neonatal Med 2020 Jul 17;33(14):2493-2504. Epub 2019 Jan 17.

Hospital General Universitario Gregorio Marañón, Madrid, Spain.

Early onset Marfan syndrome is the most severe form of Marfan syndrome diagnosed during perinatal period. Early onset Marfan syndrome is associated with high mortality rates, usually within the first 2 years of life. First, we present a case of prenatally diagnosed early onset Marfan syndrome in a dichorionic diamniotic twin pregnancy, where suspicion was raised at 35 weeks of gestation. Ultrasound and fetal magnetic resonance imaging were used to assess prenatal findings in the affected fetus. She presented right diaphragmatic eventration, elongation of humerus and femur and subluxation of the crystalline lens. She died 3 months after birth. Secondly, we present a PubMed-based review of the published articles on early onset Marfan syndrome, with pre- or postnatal suspicion or diagnosis. We found 39 articles published between 1981 and 2017, arising information on 55 cases. Including ours, early onset Marfan syndrome was prenatally diagnosed in 34.54% of the cases. In these cases, the most frequent prenatal findings were cardiomegaly, dilatation of the great vessels and mitral or tricuspid regurgitation. Mortality rate during the first 15 months after birth was 73.68%. In the postnatally diagnosed cases, the most frequent findings were arachnodactyly, dilatation of the great vessels and mitral or tricuspid regurgitation. Mortality rate was 61.11%. Overall genetic confirmation was performed in 67.27% of the cases. Prenatal diagnosis of early onset Marfan syndrome is challenging but of utmost importance, since management should take place in a tertiary care center, by a multidisciplinary team. Differential diagnosis is essential in order to perform an adequate genetic counseling.
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http://dx.doi.org/10.1080/14767058.2018.1552935DOI Listing
July 2020

Objective Assessment of Disparity Vergence after Treatment of Symptomatic Convergence Insufficiency in Children.

Optom Vis Sci 2019 01;96(1):3-16

Significance: This first report of the use of objective measures of disparity vergence as outcome measures for symptomatic convergence insufficiency in children provides additional information that is not accessible with clinical tests. The study results also demonstrate that objective measures of vergence could be used in future randomized clinical trials of binocular vision disorders with children.

Purpose: This study was designed to evaluate changes in objective measures of disparity vergence after office-based vergence/accommodative therapy (OBVAT) for convergence insufficiency in children 12 to 17 years old.

Methods: In this prospective trial, we recruited 10 participants with normal binocular vision and 12 with convergence insufficiency. All participants with convergence insufficiency were treated with 12 weeks of OBVAT. The primary outcome measure was average peak velocity for 4° symmetrical convergence steps. Other objective outcome measures of disparity vergence included time to peak velocity, latency, and accuracy. Changes in clinical measures (near point of convergence, positive fusional vergence at near) and symptoms were evaluated.

Results: There was a statistically significant increase in peak velocity and more accurate response amplitude to 4° symmetrical convergence step stimuli after OBVAT compared with baseline measurements. Near point of convergence, positive fusional vergence, and symptoms also statistically significantly improved after OBVAT. Ten of the 12 participants met clinical success criteria.

Conclusions: In this prospective study on the treatment of symptomatic convergence insufficiency in children in which both clinical and objective eye movement measurements were used to evaluate the results of treatment, significant changes were found in symptoms and both clinical and objective measures of disparity vergence after completion of OBVAT in children with symptomatic convergence insufficiency.
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http://dx.doi.org/10.1097/OPX.0000000000001320DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6305249PMC
January 2019