Pilot Study to Assess Changes in the Blink Reflex Across Age

Neurology ◽  
2021 ◽  
Vol 98 (1 Supplement 1) ◽  
pp. S22.2-S22
Author(s):  
Dena Garner
Keyword(s):  
High Speed ◽  
Objective Measure ◽  
Blink Reflex ◽  
Test Sequence ◽  
Non Invasive ◽  
Neurologic Disorders ◽  
Potential Biomarker ◽  
Before And After ◽  
Brainstem Response ◽  
The Subject

ObjectiveThe objective was to conduct a preliminary study to access blink reflex parameters across age using the Eyestat.BackgroundThe blink reflex is a primitive brainstem response to an external stimulus is affected by multiple neurologic disorders, including those that affect the dopaminergic circuit that controls the eyelid. Our laboratory has utilized a potential objective measure to identify concussions within a college aged sport population called Eyestat, which measures changes in blink reflex parameters. Prior research cited significant differences in various blink reflex parameters between active play, concussion, and baseline. However, data with older, non-athlete populations has not defined.Design/MethodsOne hundred forty three subjects between the ages of 8–80 participated in this study. Once the subject was seated, the test sequence was initiated, in which the subject placed their face into the mask and 5 random air puffs were applied to the corner of the left or right eyes over a course of 20 seconds. High-speed videography (280 frames/sec.) captured the response of the subject's eyes before and after each stimuli.ResultsDescription statistics of the data indicated differences across age with the following parameters: Latency (ms): 46.02 (ages 8–21); 47.12 (ages 22–30); 48.96 (ages 31–40); 47.44 (ages 41–50); 55.20 (ages 51–60); and 55.39 (ages 61–80). Oscillations (qty): 14.10 (ages 8–21); 14.25 (ages 22–30); 12.19 (ages 31–40); 12.75 (ages 41–50); 9.98 (ages 51–60); and 9.78 (ages 61–80). Excursions (px): 127.57 (ages 8–21); 137.46 (ages 22–30); 135.34 (ages 31–40); 144.88 (ages 41–50); 147.72 (ages 51–60); and 148.85 (ages 61–80).ConclusionsAlthough more research is warranted to determine if these differences occur with a larger subject pool, this data substantiates the need for longitudinal assessments of the blink reflex as a potential biomarker, providing a non-invasive assessment of brain health in various populations.

scholarly journals Synthetic extracellular volume fraction without hematocrit sampling for hepatic applications

2021 ◽  
Author(s):  
Narine Mesropyan ◽  
Patrick Kupczyk ◽  
Alexander Isaak ◽  
Christoph Endler ◽  
Anton Faron ◽  
...  
Keyword(s):  
Volume Fraction ◽  
Pearson Correlation ◽  
Extracellular Volume ◽  
Extracellular Volume Fraction ◽  
Radiology Department ◽  
Clinical Implementation ◽  
Derivation Cohort ◽  
Non Invasive ◽  
Potential Biomarker ◽  
Before And After

Abstract Purpose Calculation of extracellular volume fraction (ECV) currently receives increasing interest as a potential biomarker for non-invasive assessment of liver fibrosis. ECV calculation requires hematocrit (Hct) sampling, which might be difficult to obtain in a high-throughput radiology department. The aim of this study was to generate synthetic ECV for hepatic applications without the need for Hct sampling. Methods In this prospective study participants underwent liver MRI. T1 mapping was performed before and after contrast administration. Blood Hct was obtained prior to MRI. We hypothesized that the relationship between Hct and longitudinal relaxation rate of blood (R1 = 1/T1blood) could be calibrated and used to generate the equation for synthetic Htc and ECV calculation. Conventional and synthetic ECV were calculated. Pearson correlation, linear regression and Bland–Altman method were used for statistical analysis. Results 180 consecutive patients were divided into derivation (n = 90) and validation (n = 90) cohorts. In the derivation cohort, native R1blood and Hct showed a linear relationship (HctMOLLI = 98.04 × (1/T1blood) − 33.17, R2 = 0.75, P < 0.001), which was used to calculate synthetic ECV in the validation and whole study cohorts. Synthetic and conventional ECV showed significant correlations in the derivation, validation and in the whole study cohorts (r = 0.99, 0.97 and 0.99, respectively, P < 0.001, respectively) with minimal bias according to the Bland–Altman analysis. Conclusion Synthetic ECV seems to offer an alternative method for non-invasive quantification of the hepatic ECV. It may potentially overcome an important barrier to clinical implementation of ECV and thus, enable broader use of hepatic ECV in routine clinical practice.

The Development of a Portable Non-Invasive System for Analysing Human Movement

1976 ◽  
Vol 20 (16) ◽  
pp. 390-392
Author(s):  
C. O'Brien ◽  
M.G.A. Paradise
Keyword(s):  
High Speed ◽  
Human Movement ◽  
Field Of View ◽  
Cassette Tape ◽  
Non Invasive ◽  
Human Movements ◽  
Postural Changes ◽  
Portable System ◽  
The Subject ◽  
Angular Displacements

In the study of human movements, subjects are usually constrained by trailing wires or by having to remain within the field of view of a camera or other optical device. This paper describes the development of a fully portable system which allows the subject to move about quite freely in carrying out their normal daily activities. Compact straingauge electrical transducers are used to detect postural changes and to measure angular displacements at joints. The output from these transducers are fed into a battery operated miniature cassette tape recorder worn by the subject. The cassette tapes, which have a recording capacity of several hours, are played back at high speed and the output fed directly into a computer for analysis. In addition to data on angular displacements, velocities and accelerations associated with particular movements, statistical information can be obtained about a person's movement and posture throughout the day.

scholarly journals Cerebellar rTMS in PSP: a Double-Blind Sham-Controlled Study Using Mobile Health Technology

2021 ◽  
Author(s):  
Andrea Pilotto ◽  
Maria Cristina Rizzetti ◽  
Alberto Lombardi ◽  
Clint Hansen ◽  
Michele Biggi ◽  
...  
Keyword(s):  
Digital Technology ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Health Technology ◽  
Controlled Study ◽  
Double Blind ◽  
Non Invasive ◽  
Lower Back ◽  
Before And After ◽  
Double Blind Design ◽  
Theta Burst

AbstractThere are no effective treatments in progressive supranuclear palsy (PSP). The aim of this study was to test the efficacy of theta burst repetitive transcranial magnetic stimulation (rTMS) on postural instability in PSP. Twenty PSP patients underwent a session of sham or real cerebellar rTMS in a crossover design. Before and after stimulation, static balance was evaluated with instrumented (lower back accelerometer, Rehagait®, Hasomed, Germany) 30-s trials in semitandem and tandem positions. In tandem and semitandem tasks, active stimulation was associated with increase in time without falls (both p=0.04). In the same tasks, device-extracted parameters revealed significant improvement in area (p=0.007), velocity (p=0.005), acceleration and jerkiness of sway (p=0.008) in real versus sham stimulation. Cerebellar rTMS showed a significant effect on stability in PSP patients, when assessed with mobile digital technology, in a double-blind design. These results should motivate larger and longer trials using non-invasive brain stimulation for PSP patients.

scholarly journals CT perfusion in peripheral arterial disease—hemodynamic differences before and after revascularisation

2021 ◽  
Author(s):  
Patrick Veit-Haibach ◽  
Martin W. Huellner ◽  
Martin Banyai ◽  
Sebastian Mafeld ◽  
Johannes Heverhagen ◽  
...  
Keyword(s):  
Peripheral Arterial Disease ◽  
Ct Perfusion ◽  
Arterial Disease ◽  
Lower Leg ◽  
Therapy Control ◽  
Non Invasive ◽  
Before And After ◽  
Invasive Method ◽  
The Mean ◽  
Peripheral Arterial

Abstract Objectives The purpose of this study was the assessment of volumetric CT perfusion (CTP) of the lower leg musculature in patients with symptomatic peripheral arterial disease (PAD) before and after interventional revascularisation. Methods Twenty-nine consecutive patients with symptomatic PAD of the lower extremities requiring interventional revascularisation were assessed prospectively. All patients underwent a CTP scan of the lower leg, and hemodynamic and angiographic assessment, before and after intervention. Ankle-brachial pressure index (ABI) was determined. CTP parameters were calculated with a perfusion software, acting on a no outflow assumption. A sequential two-compartment model was used. Differences in CTP parameters were assessed with non-parametric tests. Results The cohort consisted of 24 subjects with an occlusion, and five with a high-grade stenosis. The mean blood flow before/after (BFpre and BFpost, respectively) was 7.42 ± 2.66 and 10.95 ± 6.64 ml/100 ml*min−1. The mean blood volume before/after (BVpre and BVpost, respectively) was 0.71 ± 0.35 and 1.25 ± 1.07 ml/100 ml. BFpost and BVpost were significantly higher than BFpre and BVpre in the treated limb (p = 0.003 and 0.02, respectively), but not in the untreated limb (p = 0.641 and 0.719, respectively). Conclusions CTP seems feasible for assessing hemodynamic differences in calf muscles before and after revascularisation in patients with symptomatic PAD. We could show that CTP parameters BF and BV are significantly increased after revascularisation of the symptomatic limb. In the future, this quantitative method might serve as a non-invasive method for surveillance and therapy control of patients with peripheral arterial disease. Key Points • CTP imaging of the lower limb in patients with symptomatic PAD seems feasible for assessing hemodynamic differences before and after revascularisation in PAD patients. • This quantitative method might serve as a non-invasive method, for surveillance and therapy control of patients with PAD.

scholarly journals Predictive values of multiple non-invasive markers for myocardial fibrosis in hypertrophic cardiomyopathy patients with preserved ejection fraction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yumin Li ◽  
Jia Liu ◽  
Yukun Cao ◽  
Xiaoyu Han ◽  
Guozhu Shao ◽  
...  
Keyword(s):  
Hypertrophic Cardiomyopathy ◽  
Ejection Fraction ◽  
Myocardial Fibrosis ◽  
Troponin I ◽  
Myocardial Strain ◽  
Left Ventricular ◽  
Preserved Ejection Fraction ◽  
Predictive Values ◽  
Non Invasive ◽  
Potential Biomarker

AbstractMyocardial fibrosis assessed by late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) is associated with cardiovascular outcomes in hypertrophic cardiomyopathy (HCM) patients, but little is known about the utility of non-invasive markers for detecting LGE. This study aims to explore the association between cardiac-specific biomarkers, CMR myocardial strain, left ventricular (LV) hypertrophy and LGE in HCM patients with preserved ejection fraction (EF) and investigate the predictive values of these indexes for LGE. We recruited 33 healthy volunteers and 86 HCM patients with preserved EF to undergo contrast-enhanced CMR examinations. In total, 48 of 86 HCM patients had the presence of LGE. The LGE-positive patients had significant higher serum high-sensitivity cardiac troponin I (hs-cTnI) and N-terminal pro b-type natriuretic peptide (Nt-proBNP) levels and lower global longitudinal (GLS) and circumferential (GCS) strains than the LGE-negative group. The LGE% was independently associated with the Nt-proBNP levels, GCS, LV end-diastolic maximum wall thickness (MWT) and beta-blocker treatment. In the receiver operating characteristic curve analysis, the combined parameters of Nt-proBNP ≥ 108.00 pg/mL and MWT ≥ 17.30 mm had good diagnostic performance for LGE, with a specificity of 81.25% and sensitivity of 70.00%. These data indicate that serum Nt-proBNP is a potential biomarker associated with LGE% and, combined with MWT, were useful for identifying myocardial fibrosis in HCM patients with preserved EF. Additionally, LV GCS may be a more sensitive indicator for reflecting the presence of myocardial fibrosis than GLS.

scholarly journals Influence of Hydrogeochemistry on Tunnel Drainage in Evaporitic Formations: El Regajal Tunnel Case Study (Aranjuez, Spain)

2021 ◽  
Vol 13 (3) ◽  
pp. 1505
Author(s):  
Ignacio Menéndez Pidal ◽  
Jose Antonio Mancebo Piqueras ◽  
Eugenio Sanz Pérez ◽  
Clemente Sáenz Sanz
Keyword(s):  
High Speed ◽  
Civil Engineering ◽  
Saturation Index ◽  
The Subject ◽  
Under Construction ◽  
Underground Flow ◽  
Very High ◽  
Over Time

Many of the large number of underground works constructed or under construction in recent years are in unfavorable terrains facing unusual situations and construction conditions. This is the case of the subject under study in this paper: a tunnel excavated in evaporitic rocks that experienced significant karstification problems very quickly over time. As a result of this situation, the causes that may underlie this rapid karstification are investigated and a novel methodology is presented in civil engineering where the use of saturation indices for the different mineral specimens present has been crucial. The drainage of the rock massif of El Regajal (Madrid-Toledo, Spain, in the Madrid-Valencia high-speed train line) was studied and permitted the in-situ study of the hydrogeochemical evolution of water flow in the Miocene evaporitic materials of the Tajo Basin as a full-scale testing laboratory, that are conforms as a whole, a single aquifer. The work provides a novel methodology based on the calculation of activities through the hydrogeochemical study of water samples in different piezometers, estimating the saturation index of different saline materials and the dissolution capacity of the brine, which is surprisingly very high despite the high electrical conductivity. The circulating brine appears unsaturated with respect to thenardite, mirabilite, epsomite, glauberite, and halite. The alteration of the underground flow and the consequent renewal of the water of the aquifer by the infiltration water of rain and irrigation is the cause of the hydrogeochemical imbalance and the modification of the characteristics of the massif. These modifications include very important loss of material by dissolution, altering the resistance of the terrain and the increase of the porosity. Simultaneously, different expansive and recrystallization processes that decrease the porosity of the massif were identified in the present work. The hydrogeochemical study allows the evolution of these phenomena to be followed over time, and this, in turn, may facilitate the implementation of preventive works in civil engineering.

scholarly journals Sensors for the detection of ammonia as a potential biomarker for health screening

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Peter P. Ricci ◽  
Otto J. Gregory
Keyword(s):  
Vapor Phase ◽  
Detection System ◽  
Health Screening ◽  
The Body ◽  
Peptic Ulcers ◽  
Non Invasive ◽  
Sensing Platform ◽  
Potential Biomarker ◽  
Screening Protocol ◽  
H Pylori

AbstractThe presence of ammonia within the body has long been linked to complications stemming from the liver, kidneys, and stomach. These complications can be the result of serious conditions such as chronic kidney disease (CKD), peptic ulcers, and recently COVID-19. Limited liver and kidney function leads to increased blood urea nitrogen (BUN) within the body resulting in elevated levels of ammonia in the mouth, nose, and skin. Similarly, peptic ulcers, commonly from H. pylori, result in ammonia production from urea within the stomach. The presence of these biomarkers enables a potential screening protocol to be considered for frequent, non-invasive monitoring of these conditions. Unfortunately, detection of ammonia in these mediums is rather challenging due to relatively small concentrations and an abundance of interferents. Currently, there are no options available for non-invasive screening of these conditions continuously and in real-time. Here we demonstrate the selective detection of ammonia using a vapor phase thermodynamic sensing platform capable of being employed as part of a health screening protocol. The results show that our detection system has the remarkable ability to selectively detect trace levels of ammonia in the vapor phase using a single catalyst. Additionally, detection was demonstrated in the presence of interferents such as carbon dioxide (CO2) and acetone common in human breath. These results show that our thermodynamic sensors are well suited to selectively detect ammonia at levels that could potentially be useful for health screening applications.

scholarly journals Characterization and Identification of Varnishes on Copper Alloys by Means of UV Imaging and FTIR

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 298
Author(s):  
Miriam Truffa Giachet ◽  
Julie Schröter ◽  
Laura Brambilla
Keyword(s):  
Copper Alloys ◽  
Analytical Techniques ◽  
Experimental Methodology ◽  
Artificial Ageing ◽  
Non Invasive ◽  
Uv Imaging ◽  
Before And After ◽  
The Comparative Study ◽  
The 19Th Century ◽  
Analytical Tools

The application of varnishes on the surface of metal objects has been a very common practice since antiquity, both for protective and aesthetic purposes. One specific case concerns the use of tinted varnishes on copper alloys in order to mimic gilding. This practice, especially flourishing in the 19th century for scientific instruments, decorative objects, and liturgical items, results in large museum collections of varnished copper alloys that need to be preserved. One of the main challenges for conservators and restorers deals with the identification of the varnishes through non-invasive and affordable analytical techniques. We hereby present the experimental methodology developed in the framework of the LacCA and VERILOR projects at the Haute École ARC of Neuchâtel for the identification of gold varnishes on brass. After extensive documentary research and analytical campaigns on varnished museum objects, various historic shellac-based varnishes were created and applied by different methods on a range of brass substrates with different finishes. The samples were then characterized by UV imaging and infrared spectroscopy before and after artificial ageing. The comparative study of these two techniques was performed for different thicknesses of the same varnish and for different shellac grades in order to implement an identification methodology based on simple non-invasive examination and analytical tools, which are accessible to conservators.

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