Search results for "VOLUME"
showing 10 items of 1932 documents
Ocular performance evaluation
2019
Real and virtual three-dimensional (3D) imaging has found useful applications across different areas of health sciences and with the current rapidly progressive development stage we can expect that the use of 3D imaging soon will be a part of a daily visual load for medical personnel. To better understand the possible impact of prolonged work with 3D content on eye accommodative response and pupil size we compared two 3D imaging techniques - volumetric display that is real voxel-based system and anaglyph technique that is virtual pixel-based system. We have investigated accommodative lag and pupil responses in 38 emmetropic young adult after prolonged visual task with volumetric 3D display …
Mechanisms of Cell-Volume Regulation in the Central Nervous System
2017
Function and viability of every cell is dependent on the proper control of its shape and volume. In the brain, which is protected by a rigid outer shell, cell-volume regulation is of particular importance, since large volume changes affect cerebral perfusion and, hence, function. Neuronal activation leads to constant changes of the ionic and metabolic composition of the brain’s extracellular space. These changes are buffered by astrocytes on the expense of constant changes in cell volume. Under pathological conditions, the ability of astrocytes to maintain the homeostasis of the brain is overwhelmed and permanent cell swelling, cytotoxic edema, occurs. The current chapter describes the prin…
Optical multichannel monitoring of skin blood pulsations for cardiovascular assessment
2004
Time resolved detection and analysis of the skin back-scattered optical signals (reflection photoplethysmography or PPG) provide rich information on skin blood volume pulsations and can serve for cardiovascular assessment. The multichannel PPG concept has been developed and clinically verified in this work. Simultaneous data flow from several body locations allows to study the heartbeat pulse wave propagation in real time and to evaluate the vascular resistance. Portable two- and four-channel PPG monitoring devices and special software have been designed for real-time data acquisition and processing. The multi-channel devices were successfully applied for cardiovascular fitness tests and fo…
ESRA19-0692 Which preoperative tests before regional anaesthetic procedures?
2019
As we know, any regional anaesthesia technique stays under failure risks. What anaesthetists have to know about the regional block before let the surgeons start after regional anaesthesia? There are few positions which should be confirmed by tests. Firstly, detect the onset of successful sensitive, motor and sympathetic block. Secondly, confirm the correct area of the regional block. Furthermore, the anaesthetist should understand if the regional block performed under deep sedation or general anaesthesia will be effective also after the surgery. What we have to remember and what we need to check for this reason? Pain is subjective phenomenon. Are we determined as dependent on the patient‘s …
Comparative assessment of brain activity during depth perception of stereoscopic and volumetric images
2020
Recent advancements in visualization systems have triggered a growing demand for the objective and accurate comparison of user cognitive requirements when perceiving three-dimensional images demonstrated in different ways. In this work, we present the first comparative assessment of brain activity in subjects viewing stereoscopic images and volumetric images. Electroencephalography was employed to assess the short-term changes in event related potentials and neural oscillations which were further interpreted in terms of cognitive requirements for relative depth judgments. As a result, considerably higher activity have been registered in the beta band and gamma band in case of judging relati…
An automatic method for metabolic evaluation of gamma knife treatments
2015
Lesion volume delineation of Positron Emission Tomography images is challenging because of the low spatial resolution and high noise level. Aim of this work is the development of an operator independent segmentation method of metabolic images. For this purpose, an algorithm for the biological tumor volume delineation based on random walks on graphs has been used. Twenty-four cerebral tumors are segmented to evaluate the functional follow-up after Gamma Knife radiotherapy treatment. Experimental results show that the segmentation algorithm is accurate and has real-time performance. In addition, it can reflect metabolic changes useful to evaluate radiotherapy response in treated patients.
Functional In Vitro Studies Of Buffy Coat Pooled Platelets Cryopreserved In Dimethyl-Sulphoxide With a New System
2013
Abstract Introduction Cryopreservation for long term storage of platelets (PLTs) represents a clinical useful method for avoiding platelet shortage. Many studies have tried to define, in vitro and in vivo, the entity and weight of storage-related PLTs lesions with discordant results related to different methods. We have performed an in vitro prospective study to evaluate PLTs count, viability and function of buffy coat derived pooled platelet concentrates (BC-PLTs) treated with dimethyl-sulphoxide (DMSO) and cryopreserved at -80°C with an innovative patented system not requiring laminal flow hoods and external manipulations. Materials and methods Each BC-PLTs was obtained from 5 buffy coats…
Rationale and Design of the Efficacy of a Standardized Diuretic Protocol in Acute Heart Failure Study
2021
AIMS: Although acute heart failure (AHF) with volume overload is treated with loop diuretics, their dosing and type of administration are mainly based upon expert opinion. A recent position paper from the Heart Failure Association (HFA) proposed a step-wise pharmacologic diuretic strategy to increase the diuretic response and to achieve rapid decongestion. However, no study has evaluated this protocol prospectively. METHODS AND RESULTS: The Efficacy of a Standardized Diuretic Protocol in Acute Heart Failure (ENACT-HF) study is an international, multicentre, non-randomized, open-label, pragmatic study in AHF patients on chronic loop diuretic therapy, admitted to the hospital for intravenous …
Creatinine and NT-ProBNP levels could predict the length of hospital stay of patients with decompensated heart failure.
2021
Heart failure (HF) is a clinical syndrome that causes high morbidity and mortality with a high number of admissions and sometimes prolonged admissions. This study aimed at assessing whether parameters detected during the first 24 h of admission may predict a prolonged hospital stay in patients admitted to hospital for decompensated HF.From January 2016 to December 2019, 2359 admissions of decompensated HF were recorded. In-hospital transfers,Univariate differences were found at admission in NT-ProBNP, creatinine, history of cardiac surgery, smoking and alcoholism, left and right ventricular ejection fraction, systolic blood pressure and heart rate. The ROC analysis showed significant areas …
Tagesprofile von Plasmaaldosteron,-Cortisol, -Renin, -Angiotensinogen und -Angiotensinasen bei Normalpersonen
1976
Plasma cortisol and renin were estimated in 1 h intervals, plasma aldosterone, angiotensinogen and angiotensinases in 3 h intervals over periods of 24 h in six normal volunteers (age 20-26) under control conditions and subsequently under suppression of ACTH release by dexamethasone. Highest cortisol levels were found around 7 a.m., minimum levels between 9 p.m. and 1 a.m. Dexamethasone reduced cortisol to constantly low concentrations. Aldosterone was highest around 4 a.m. under control conditions and under dexamethasone, and showed lowest concentrations between 4 and 10 p.m. There were no significant differences between mean aldosterone concentrations at corresponding time points of the co…