Publications using the PortaLite
Using Signal Features of Functional Near-Infrared Spectroscopy for Acute Physiological Score Estimation in ECMO Patients
Extracorporeal membrane oxygenation (ECMO) is a vital emergency procedure providing respiratory and circulatory support to critically ill patients, especially those with compromised cardiopulmonary function. Its use has grown due to technological …
Near-Infrared Spectroscopy measurements are reliable for studying patellar bone hemodynamics and affected by venous occlusion, but not by skin compression
Abstract Purpose According to the homeostasis model, patellofemoral pain (PFP) results from disturbed homeostasis due to vascular insufficiency in the anterior knee. Near-Infrared Spectroscopy (NIRS) measures relative changes in concentrations (in …
Self-calibrated pulse oximetry algorithm based on photon pathlength change and the application in human freedivers
Significance Pulse oximetry estimates the arterial oxygen saturation of hemoglobin (SaO2) based on relative changes in light intensity at the cardiac frequency. Commercial pulse oximeters require empirical calibration on healthy volunteers, resulting …
The effects of sleep deprivation, acute hypoxia, and exercise on cognitive performance: A multi-experiment combined stressors study
Introduction Both sleep deprivation and hypoxia have been shown to impair executive function. Conversely, moderate intensity exercise is known to improve executive function. In a multi-experiment study, we tested the hypotheses that moderate …
Acute Effects of a Practical Blood Flow Restriction Device During Swimming Exercise
Purpose: The present study aimed to analyze: 1) the reliability of the tissue saturation index (TSI) and ratings of perceived discomfort (RPD) responses wearing a neoprene practical cuff (PrC), comparing with the responses from traditional (TrC) …
Chronotype predicts working memory-dependent regional cerebral oxygenation under conditions of normal sleep and following a single night of sleep extension
Abstract The aim of this study was to test the hypothesis that the association between sleep duration and brain activation as assessed by regional cerebral oxygenation using near-infrared spectroscopy (NIRS) is dependent on chronotype. Sleep was …
Functional Analysis of Continuous, High-Resolution Measures in Aging Research: A Demonstration Using Cerebral Oxygenation Data From the Irish Longitudinal Study on Aging
Background: A shift towards the dynamic measurement of physiologic resilience and improved technology incorporated into experimental paradigms in aging research is producing high-resolution data. Identifying the most appropriate analysis method for …
Impaired Stabilization of Orthostatic Cerebral Oxygenation Is Associated With Slower Gait Speed: Evidence From The Irish Longitudinal Study on Ageing
Abstract Background Cerebral autoregulation (CAR) systems maintain blood flow to the brain across a wide range of blood pressures. Deficits in CAR have been linked to gait speed (GS) but previous studies had small sample sizes and used specialized …
Intermittent neck flexion induces greater sternocleidomastoid deoxygenation than inspiratory threshold loading
Purpose To compare deoxygenation of the sternocleidomastoid, scalenes, and diaphragm/intercostals (Dia/IC) during submaximal intermittent neck flexion (INF) versus submaximal inspiratory threshold loading (ITL) in healthy adults. Methods Fourteen …
Evaluation of transcutaneous near-infrared spectroscopy for early detection of cardiac arrest in an animal model
Abstract Sudden cardiac arrest (SCA) is a leading cause of mortality worldwide. The SCA-to-resuscitation interval is a key determinant of patient outcomes, highlighting the clinical need for reliable and timely detection of SCA. Near-infrared …
Mild cognitive impairment estimation based on functional near‐infrared spectroscopy
Abstract Patients with mild cognitive impairment (MCI) are at a high risk of developing future dementia. However, early identification and active intervention could potentially reduce its morbidity and the incidence of dementia. Functional …
Ambulatory monitoring of cerebrovascular responses to upright posture and walking in older adults with heart failure
Background Insufficient cardiac output (Q) in individuals with heart failure (HF) limits daily functioning and reduces quality of life. While lower cerebral perfusion, secondary to limitations in Q, has been observed during moderate-intensity …
Structural and functional impairments of skeletal muscle in patients with postacute sequelae of SARS-CoV-2 infection
Several months after mild acute SARS-CoV-2 infection, a substantial proportion of patients present persisting, and often debilitating, symptoms and sequelae. These patients show reduced quality of life due to exercise intolerance, muscle weakness, …
Safety and feasibility of transcutaneous vagus nerve stimulation in mild cognitive impairment: VINCI-AD study protocol
Abstract Background Over 55 million adults are living with dementia globally, which is projected to reach 157 million by 2050. Mild cognitive impairment (MCI), a syndrome of memory impairment with intact activities of daily living, may precede …
A promising tool to explore functional impairment in neurodegeneration: A systematic review of near-infrared spectroscopy in dementia.
his systematic review aimed to evaluate previous studies which used near-infrared spectroscopy (NIRS) in dementia given its suitability as a diagnostic and investigative tool in this population. From 800 identified records which used NIRS in dementia …
The prefrontal cortex hemodynamic responses to dual-task paradigms in older adults: A systematic review and meta-analysis
Background Functional near-infrared spectroscopy (fNIRS) is a method to measure cerebral hemodynamics. Determining the changes in prefrontal cortex (PFC) hemodynamics during dual-task paradigms is essential in explaining alterations in physical …
Reactive hyperemia half-time response is associated with skeletal muscle oxygen saturation changes during cycling exercise
We investigated the relationship between muscle microvascular responses during reactive hyperemia as assessed using near-infrared spectroscopy (NIRS) with changes in skeletal muscle oxygen saturation during exercise. Thirty young untrained adults …
Effects of Posture and Walking on Tibial Vascular Hemodynamics Before and After 14 Days of Head‐Down Bed Rest
Human skeletal hemodynamics remain understudied. Neither assessments in weight-bearing bones during walking nor following periods of immobility exist, despite knowledge of altered nutrient-artery characteristics after short-duration unloading in …
Local microvascular tissue oxygenation of the intrinsic foot muscles in patients with diabetes: A cross-sectional case-comparison study
Background Foot-related complications including impaired peripheral circulation and lower limb ulceration are severe consequences for those with diabetes mellitus. This study aimed to assess differences in tissue oxygenation and oxygen utilization of …
Women Have Greater Endothelin-B Receptor Function and Lower Mitochondrial Capacity Compared to Men With Type 1 Diabetes
Abstract Context Type 1 diabetes (T1D) negatively affects both the endothelin system and muscle oxidative capacity. The endothelin pathway is a critical regulator of microcirculatory function and may exhibit sexual dichotomy by which healthy …