A5006992656- Optical Imaging and Spectroscopy Techniques
- Non-Invasive Vital Sign Monitoring
- Photoacoustic and Ultrasonic Imaging
- Traumatic Brain Injury and Neurovascular Disturbances
- Hemodynamic Monitoring and Therapy
- Spectroscopy Techniques in Biomedical and Chemical Research
- Photodynamic Therapy Research Studies
- EEG and Brain-Computer Interfaces
- Neonatal and fetal brain pathology
- Heart Rate Variability and Autonomic Control
- Infrared Thermography in Medicine
- Cardiac, Anesthesia and Surgical Outcomes
- Advanced MRI Techniques and Applications
- Cardiovascular Health and Disease Prevention
- Cerebrospinal fluid and hydrocephalus
- Organ Donation and Transplantation
- Traumatic Brain Injury Research
- Water Quality Monitoring and Analysis
- Spectroscopy and Chemometric Analyses
- Cerebrovascular and Carotid Artery Diseases
- Neonatal Respiratory Health Research
- Thermoregulation and physiological responses
- Ultrasound and Hyperthermia Applications
- Spectroscopy and Laser Applications
- Neurogenesis and neuroplasticity mechanisms
Western University
2016-2025
Lawson Health Research Institute
2016-2025
Institute of Biocybernetics and Biomedical Engineering
2010-2019
Polish Academy of Sciences
2010-2019
University of Florence
2015
A multi-center study has been set up to accurately characterize the optical properties of diffusive liquid phantoms based on Intralipid and India ink at near-infrared (NIR) wavelengths.Nine research laboratories from six countries adopting different measurement techniques, instrumental set-ups, data analysis methods determined their best relative uncertainties dilutions prepared with common samples two compounds.By exploiting a suitable statistical model, comprehensive reference values three...
Performance assessment of instruments devised for clinical applications is key importance validation and quality assurance. Two new protocols were developed applied to facilitate the design optimization time-domain optical brain imaging within European project nEUROPt. Here, we present “Basic Instrumental Performance” protocol direct measurement relevant characteristics. tests are discussed in detail. First, responsivity detection system a measure overall efficiency detect light emerging...
The nEUROPt protocol is one of two new protocols developed within the European project to characterize performances time-domain systems for optical imaging brain. It was applied in joint measurement campaigns compare various instruments and assess impact technical improvements. This addresses characteristic brain detect, localize, quantify absorption changes implemented with types inhomogeneous liquid phantoms based on Intralipid India ink well-defined properties. First, small black...
Significance: Near-infrared spectroscopy (NIRS) combined with diffuse correlation (DCS) provides a noninvasive approach for monitoring cerebral blood flow (CBF), oxygenation, and oxygen metabolism. However, these methods are vulnerable to signal contamination from the scalp. Our work evaluated of reducing impact this using time-resolved (TR) NIRS multidistance (MD) DCS. Aim: The magnitude scalp was by measuring flow, metabolic responses global hemodynamic challenge. Contamination assessed...
We study fluorescence lifetime of indocyanine green (ICG) using femtosecond laser and sensitive detection based on time-correlated single-photon counting. A time-resolved multichannel spectral system is constructed applied for determination the ICG in different solvents. Emission properties water, milk, 1% intralipid solution are investigated. Fluorescence fluorophore concentrations (in a range 1.7-160 μM) dissolved solutions excited by pulses generated with use Ti:Sa tuned within 740-790...
The in-vivo optical properties of the human head are investigated in 600-1100 nm range on different subjects using continuous wave and time domain diffuse spectroscopy. work was performed collaboration with research groups techniques were applied to same subject. Data analysis carried out homogeneous layered models final results also confirmed by Monte Carlo simulations. depth sensitivity each technique related probed region cerebral tissue. This work, based validated instruments, is a...
We investigate a scheme for noninvasive continuous monitoring of absolute cerebral blood flow (CBF) in adult human patients based on combination time-resolved dynamic contrast-enhanced near-infrared spectroscopy (DCE-NIRS) and diffuse correlation (DCS) with semi-infinite head model photon propogation. Continuous CBF is obtained via calibration the DCS index (BFI) by intermittent intravenous injections optical contrast agent indocyanine green. A coefficient (γ) thus determined, permitting...
There is a growing interest in the possibility of using functional neuroimaging techniques to aid detecting covert awareness patients who are thought be suffering from disorder consciousness. Immerging optical such as time-resolved near-infrared spectroscopy (TR-fNIRS) ideal for applications due their low-cost, portability, and enhanced sensitivity brain activity. The aim this case study was investigate first time ability TR-fNIRS detect command driven motor imagery (MI) activity...
Brain-computer interfaces (BCI) are becoming increasingly popular as a tool to improve the quality of life patients with brain injuries. Recently, time-resolved functional near-infrared spectroscopy (TR-fNIRS) based BCIs gaining traction because enhanced depth sensitivity leading lower signal contamination from extracerebral layers. In this study, we present first account TR-fNIRS BCI for 'mental communication' on healthy participants. 21 participants were recruited and repeatedly asked...
Previous functional magnetic resonance imaging (fMRI) studies have shown that a subgroup of patients diagnosed as being in vegetative state are aware and able to communicate by performing motor imagery task response commands.Due the fMRI's cost accessibility, there is need for exploring different modalities can be used at bedside.A promising technique near infrared spectroscopy (fNIRS) has been successfully applied measure brain oxygenation humans.Due limited depth sensitivity...
The purpose of this study was to assess the accuracy absolute cerebral blood flow (CBF) measurements obtained by dynamic contrast-enhanced (DCE) near-infrared spectroscopy (NIRS) using indocyanine green as a perfusion contrast agent. For validation, CBF measured independently MRI method arterial spin labeling (ASL). Data were acquired at two sites and under conditions (normocapnia hypercapnia). Depth sensitivity enhanced time-resolved detection, which demonstrated in separate set experiments...
During cardiac surgery with cardiopulmonary bypass (CPB), adequate maintenance of cerebral blood flow (CBF) is vital in preventing postoperative neurological injury - i.e. stroke, delirium, cognitive impairment. Reductions CBF large enough to impact energy metabolism can lead tissue damage and subsequent brain injury. Current methods for neuromonitoring during are limited. This study presents the clinical translation a hybrid optical neuromonitor continuous intraoperative monitoring...
Over the last few decades, neuroimaging techniques have transformed our understanding of brain and effect neurological conditions on function. More recently, light-based modalities such as functional near-infrared spectroscopy gained popularity tools to study function at bedside. A recent application is assess residual awareness in patients with disorders consciousness, some retain albeit lacking all behavioural response commands. Functional can play a vital role identifying these by...
Recently, it was shown in measurements carried out on humans that time-resolved near-infrared reflectometry and fluorescence spectroscopy may allow for discrimination of information originating directly from the brain avoiding influence contaminating signals related to perfusion extracerebral tissues. We report continuation these studies, showing light can be detected noninvasively surface tissue at large interoptode distance. A multichannel optical monitoring system constructed diffuse...
A relationship between the brain rhythmic activity and hemodynamic response was studied using simultaneous measurement of electroencephalogram (EEG) functional near-infrared spectroscopy (fNIRS) during a motor task (self-paced right finger movements) for 10 subjects. An EEG recording with 32-electrode (10-10) system made obtained 8 optodes placed over sensorimotor cortex on both hemispheres. During an increase in oxyhemoglobine (HbO) accompanied by decrease deoxyhemoglobine (HbR)...
The aim of this study was to evaluate enhancing the depth sensitivity timeresolved near-infrared spectroscopy with a subtraction-based approach.Due complexity light propagation in heterogeneous media, and prove validity proposed method turbid media we conducted broad analysis taking into account number parameters related as well various media.The results these experiments confirm that approach is better than classical approaches using continuous-wave or time-resolved methods.Furthermore,...
This study presents the characterization of dynamic cerebrovascular reactivity (CVR) in healthy adults by a hybrid optical system combining time-resolved (TR) near-infrared spectroscopy (NIRS) and diffuse correlation (DCS). Blood flow oxygenation (oxy- deoxy-hemoglobin) responses to step hypercapnic challenge were recorded characterize static components CVR. Data acquired at short long source-detector separations ( r SD ) assess impact scalp hemodynamics, moment analysis applied TR-NIRS...
A major concern with preterm birth is the risk of neurodevelopmental disability. Poor cerebral circulation leading to periods hypoxia believed play a significant role in etiology brain injury, first three days life considered period when most vulnerable. This study focused on monitoring perfusion and metabolism during 72 h after infants weighing less than 1500 g. Brain was performed by combining hyperspectral near-infrared spectroscopy assess oxygen saturation oxidation state cytochrome c...
Cerebral oximeters have the potential to detect abnormal cerebral blood oxygenation allow for early intervention. However, current commercial systems two major limitations: (1) spatial coverage of only frontal region, assuming that surgery-related hemodynamic effects are global and (2) susceptibility extracerebral signal contamination inherent continuous-wave near-infrared spectroscopy (NIRS).
Abstract Time-resolved near-infrared spectroscopy is an optical technique which can be applied in tissue oxygenation assessment. In the last decade this method extensively tested as a potential clinical tool for noninvasive human brain function monitoring and imaging. present paper we show construction of instrument allows for: (i) estimation changes using two-wavelength approach (ii) perfusion assessment with use single-wavelength reflectometry or fluorescence measurements combined...
The blood-brain barrier (BBB) is integral to maintaining a suitable microenvironment for neurons function properly. Despite its importance, there are no bedside methods of assessing BBB disruption help guide management critical-care patients. aim this study was demonstrate that dynamic contrast-enhanced (DCE) near-infrared spectroscopy (NIRS) can quantify the permeability surface-area product (PS) BBB. Experiments were conducted in rats which opened by image-guided focused ultrasound....
An optical technique based on diffuse reflectance measurement combined with indocyanine green (ICG) bolus tracking is extensively tested as a method for the clinical assessment of brain perfusion at bedside. We report multiwavelength time-resolved spectroscopy measurements carried out head healthy adult during intravenous administration ICG. Intracerebral and extracerebral changes in absorption were estimated from an analysis statistical moments (total number photons, mean time flight...