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Ischemic cerebral edema (CE) is a major leading cause of death in patients with ischemic stroke. The CE progression is closely related to the local cerebral blood perfusion (LCBP) level surrounding the edema area. Quantitative studying the interaction between the CE and peripheral LCBP may provide new inspiration for control and even treatment of CE.

Photothrombosis ischemia mouse model was established and observed for 9 hours using swept-source optical coherence tomography (SS-OCT). this website OCT-based angiography and OCT-based attenuation imaging techniques were used to reconstruct the angiograms reflecting the cerebral blood perfusion (CBP) level and optical attenuation coefficient (OAC) maps reflecting the edema state. The influence of edema on LCBP was analyzed by quantifying the blood perfusion in different spatial locations around the edema tissue, and the influence of LCBP on CE progression was revealed by comparing the changes of the edema area and LCBP level over time.

Preliminary studies show that the E. This work provides a new method and inspiration for exploring the mechanism of ischemic CE progression.

Optical coherence tomography (OCT) imaging is inherently susceptible to distortion artifacts due to the natural curvature of the eye. This study proposes a novel model for widefield OCT angiography (OCTA) distortion correction and analyzes the effects of this correction on quantification metrics.

Widefield OCTA images were obtained on normal subjects at five fixation spatial positions. Radial and field distortion correction were applied and images stitched together to form a corrected widefield montage image. Vessel area density (VAD), vessel complexity index (VCI), and flow impairment area were quantified on the original and corrected montage images.

This model allows for distortion correction and montaging of widefield images. There were either statistically insignificant or small magnitude changes in vessel density and vessel complexity between uncorrected and corrected widefield images. There was a significant and large difference in flow impairment area, both in the macular (+8.2%, P=0.049) and peripheral areas (+17.2%, P=0.011), following correction. The relationship between pre- and post-correction flow impairment area was non-linear.

Distortion correction of widefield OCTA images can result in clinically and statistically significant differences in important quantification metrics. This effect appears to be most pronounced in the periphery.

Distortion correction of widefield OCTA images can result in clinically and statistically significant differences in important quantification metrics. This effect appears to be most pronounced in the periphery.

Quantitatively investigating the biomechanics of retina with a retinal prosthetic electrode, we explored the effects of the prosthetic electrode on the retina, and further supplemented data for a potential clinical trial.

Biomechanical properties were assessed with a high resolution optical coherence tomography (OCT) based elastography (OCE) system. A shaker was used to initiate elastic waves and an OCT system was used to track axial displacement along with wave propagation. Rabbits received surgery to implant the retinal prosthetic electrode, and elastic wave speed was measured before and after implantation; anatomical B-mode images were also acquired.

Spatial-temporal maps of each layer in retina with and without prosthetic electrodes were acquired. Elastic wave speed of nerve fiber to inner plexiform layer, inner nuclear to outer nuclear layer, retinal pigmented epithelium layer and choroid to sclera layer without prosthetic electrode were found to be 3.66±0.36, 5.33±0.07, 6.85±0.37, and 9.69±0.24 m/rties of the retina in response to long term use of prosthetic electrodes in patients.

Photoplethysmography (PPG) is routinely used to detect the blood pulse signal from skin tissue beds in clinics. However, the origin of the PPG signal remains controversial. The purpose of this study is to explore optical coherence tomography angiography (OCTA) to indicate pulsatile waveforms in the papillary plexus and dermal plexus separately under different hand elevations.

Optical microangiography (OMAG) algorithm was used to obtain a 3D OCTA signals, from which the depth-resolved pulsatile blood flow signals were extracted from different skin vascular plexus. The systolic amplitude, crest time, and delta T were measured from the OCTA pulsatile signals when the hand was placed at the positions of 50 cm below, 0 cm, and 50 cm above the heart level.

The pulse signal integrated from all the depths has a similar waveform to that of the PPG and showed the same morphological change at different hand elevations. The pulsatile patterns from the papillary plexus and dermal plexus showed distinct morphologicalanges at different skin circulatory plexus.

Vascular quantitative metrics have been widely used in the preclinical studies and clinical applications (e.g., the diagnosis and treatment of port wine stain, PWS), which require accurate vessel segmentation. An automatic 3D adaptive vessel segmentation is in need for a reproducible and objective quantification of the optical coherence tomography angiography (OCTA) image.

Human skin imaging was performed with a lab-built optical coherence tomography (OCT) system. Rather than separately applying the conventional 2-step (intensity and binarization) thresholding in the decorrelation-contrast OCTA, we proposed a 3D adaptive threshold using the linear relationship between the local intensity and complex-decorrelation which was termed as inverse SNR-decorrelation (ID) threshold. Furthermore, the ID threshold was automatically determined by defining a binary image similarity (BISIM) index as the feedback and searching the ID threshold with the minimal BISIM value. The proposed ID-BISIM threshold was applied to WS.

The proposed ID-BISIM method enables an automatic 3D adaptive vessel segmentation with enhanced performance in quantitative OCTA. The vascular quantitative metrics would be a useful tool for improving the diagnosis and the treatment of PWS.

In the clinical applications of optical coherence tomography angiography (OCTA), the repeated scanning and averaging method can provide better contrast with reduced speckle noises in the final results, which are useful for visualizing and quantifying vascular components with high accuracy, reproducibility, and reliability. However, the inevitable patient motion presents a challenge to this method. The objective of this study is to meet this challenge by introducing a 3D registration method to register optical coherence tomography (OCT)/OCTA scans for precise volume averaging of multiple scans to improve the signal-to-noise ratio (SNR) and increase quantification accuracy.

The proposed method utilized both rigid affine transformation and non-rigid B-spline transformation in which their parameters were optimized and calculated by the average stochastic gradient descent on OCT structural images. In addition, we also introduced a multi-level resolution approach to further improve the robustness and computatiowhich would be beneficial to OCT clinical applications.

The proposed 3D registration and averaging method is effective in reducing speckle noises and suppressing motion artifacts, thereby improving SNR, PSNR and NCC metrics for final averaged images. It is expected that the proposed algorithm would be practically useful in better visualization and more reliable quantification of in vivo OCT and OCTA data, which would be beneficial to OCT clinical applications.The corona virus pandemic at the international and national levels constitutes a real problem for health, economy, trade and certainly education. In Morocco, general confinement, since March 20, 2020, is an obligation to limit the spread of this virus. The Ministry of National Education decided to close education and training institutions on March 16, 2020. It adopted, in parallel, several proactive and preventive measures to deal with this pandemic on several levels, including distance education. Certainly these measures taken in the field of education are highly important, but require reinforcement for a continuous improvement of the safety and health of learners and the professional body. Continuous prevention measures are proposed in this study, acting on legal, human resources and educational content aspects, as well as on the preventive aspect on which we offer simplified methods and tools for the effective management of COVID-19 risk. In particular, we propose a checklist, adapted to the school context, used to carry out periodic internal audits for regular control and monitoring of the health situation in the school institution and the implementation of corrective and preventive actions.COVID (Corona Virus) 2019 proved to be a pandemic worldwide, with more than 30 lakhs of life's in danger and more than 2 lakh people dead as of 01 May 2020. The disease is spreading across the world in various phases, with assumptions of having an impact based on the weather conditions, where the true reason is not yet confirmed. However, several precautionary measures such as maintaining social distancing, covering mouth and hands using masks and gloves, avoiding huge public gatherings to attend conferences, meetings, worship places, etc proved to put a pause on the spread of this air-borne contagious disease. Though there is an impact on the overall economy world-wide, lockdown is strictly implemented in countries like India and also at various other places to control the spread and save several lives. There is a necessity to track the spread to find out the rate at which the virus is spreading and accordingly taking measures to control the same. This work presents an analysis of the growth rate and death rate of the COVID pandemic in developing countries like India using the Auto regression-based Moving Average method. The results presented in this work show the future predictions analyzed via the proposed model and drives a path to take preventive measures accordingly and curb the COVID spread.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) appeared in Wuhan, China, in December 2019; apart from common conditions such as cough, fever, and severe respiratory complications, difficulty in breathing, including tachypnea, new studies on neurological manifestations have gained public interest.

An 89-year-old man was admitted to the neurocritical care department in a specialized hospital with headache, dizziness, hyperpyrexia, myalgia, rash, and tremors. MRI showed viral encephalitis near to basal ganglia and thalami.

Coronaviruses interfere with target cells by membrane-bound spike proteins. Angiotensin-converting enzyme 2 was identified as an input receptor for SARS-CoV-2. Due to its wide pattern of expression, COVID-19 was shown to affect several organs, including the central nervous system, where the receptor is mainly expressed as neurons.

In the current pandemic, there is a rising number of global infections, the aim of our case to increase the awareness about SARS-CoV-2 possible complications, even if there are possible further mutations for the virus, especially in the central nervous system.

In the current pandemic, there is a rising number of global infections, the aim of our case to increase the awareness about SARS-CoV-2 possible complications, even if there are possible further mutations for the virus, especially in the central nervous system.