Pulse oximetry has been used for diagnosing cyanosis, dyspnea and tachypnea (Schutz and Saunders., 2001). However, it is limited by accuracy-inhibiting factors, such as; decreased peripheral pulses, body temperature and blood pressure.
This document describes an experiment that used near-infrared spectroscopy (NIRS) to noninvasively measure the optical properties of a songbird's brain. Researchers placed optical fibers on the head of anesthetized zebra finches to transmit laser light and collect the light after it passed through the brain tissue. They were able to measure the absorption and scattering coefficients of the caudal nidopallium region of the brain in vivo. This technique could help monitor brain activity and oxygenation levels in songbirds.
Microdialysis is an integral part of preclinical research to determine extracellular fluid and blood concentrations of metabolites, hormones, drugs, etc, and is often used in quantifying the biochemistry of brain and peripheral tissues. However, it is a molecular-only technique and other imaging modalities are needed to provide the researcher with functional and anatomical information of the animal in vivo.
The IVIS SpectrumCT is an imaging system that integrates optical and microCT imaging modalities to enable simultaneous molecular and anatomical longitudinal studies in small animal models. It provides unparalleled performance for low-dose microCT imaging and automated co-registration of optical and microCT data. Multiple animals can be scanned simultaneously using optical imaging techniques like fluorescence, bioluminescence, and Cerenkov luminescence, while microCT scans have an average dose of 13mGy and take less than a minute.
This document describes a study on using mid-infrared absorption spectroscopy for label-free detection of phospholipid biomarkers. Phospholipids exhibit strong absorption resonances in the mid-infrared region and are detectable using this technique. The study explores separating phospholipid biomarkers using on-chip capillary electrophoresis in a PDMS microfluidic chip, and then performing label-free detection of the separated biomarkers using mid-infrared absorption spectroscopy by interrogating the biomarkers in the microfluidic channel. Initial experiments detect a phospholipid called phosphatidic acid dissolved in a non-aqueous solvent using this approach, demonstrating the feasibility of the technique for label-free phospholipid sensing.
The document describes tests performed on a motor shaft and lens-transducer system to ensure proper motion and alignment. T-tests and ANOVAs showed the motor shaft traveled the expected distance and the forward and backward motion of the lens-transducer system were equivalent. Adding a track prevented unacceptable deflection from the system's mass. Images taken during 2mm intervals showed majority of motion was below the 1mm deviation limit, though future design changes could improve accuracy.
Application Brief: Tumor Microenvironment Imaging with Photoacoustic TechnologyFUJIFILM VisualSonics Inc.
Combining photoacoustic technology with high-resolution ultrasound projections offered by the Vevo 2100 system provides tremendous benefits for cancer screening. Researchers can now benefit from the combined high-resolution ultrasound and optical contrast ability of the Vevo® LAZR photoacoustic imaging system to achieve clear, deep, images in 2D and 3D for optimal in vivo visualization and quantification of internal anatomy, tumor tissue, and hemodynamics.
Photoacoustic Imaging with Coherent Light - Emmanuel BossySébastien Popoff
This document summarizes a presentation on photoacoustic imaging with coherent light. It discusses how photoacoustics can be used to image in optically scattering media by coupling light and ultrasound. Two approaches for photoacoustic image formation are described: reconstruction-free imaging using time-resolved signals and reconstruction-based tomography. Enhanced imaging techniques using speckle illumination and wavefront shaping are presented, including a photoacoustic transmission matrix approach that allows focusing light through scattering samples. Challenges and potential solutions for deep tissue imaging are also outlined.
This document describes an experiment that used near-infrared spectroscopy (NIRS) to noninvasively measure the optical properties of a songbird's brain. Researchers placed optical fibers on the head of anesthetized zebra finches to transmit laser light and collect the light after it passed through the brain tissue. They were able to measure the absorption and scattering coefficients of the caudal nidopallium region of the brain in vivo. This technique could help monitor brain activity and oxygenation levels in songbirds.
Microdialysis is an integral part of preclinical research to determine extracellular fluid and blood concentrations of metabolites, hormones, drugs, etc, and is often used in quantifying the biochemistry of brain and peripheral tissues. However, it is a molecular-only technique and other imaging modalities are needed to provide the researcher with functional and anatomical information of the animal in vivo.
The IVIS SpectrumCT is an imaging system that integrates optical and microCT imaging modalities to enable simultaneous molecular and anatomical longitudinal studies in small animal models. It provides unparalleled performance for low-dose microCT imaging and automated co-registration of optical and microCT data. Multiple animals can be scanned simultaneously using optical imaging techniques like fluorescence, bioluminescence, and Cerenkov luminescence, while microCT scans have an average dose of 13mGy and take less than a minute.
This document describes a study on using mid-infrared absorption spectroscopy for label-free detection of phospholipid biomarkers. Phospholipids exhibit strong absorption resonances in the mid-infrared region and are detectable using this technique. The study explores separating phospholipid biomarkers using on-chip capillary electrophoresis in a PDMS microfluidic chip, and then performing label-free detection of the separated biomarkers using mid-infrared absorption spectroscopy by interrogating the biomarkers in the microfluidic channel. Initial experiments detect a phospholipid called phosphatidic acid dissolved in a non-aqueous solvent using this approach, demonstrating the feasibility of the technique for label-free phospholipid sensing.
The document describes tests performed on a motor shaft and lens-transducer system to ensure proper motion and alignment. T-tests and ANOVAs showed the motor shaft traveled the expected distance and the forward and backward motion of the lens-transducer system were equivalent. Adding a track prevented unacceptable deflection from the system's mass. Images taken during 2mm intervals showed majority of motion was below the 1mm deviation limit, though future design changes could improve accuracy.
Application Brief: Tumor Microenvironment Imaging with Photoacoustic TechnologyFUJIFILM VisualSonics Inc.
Combining photoacoustic technology with high-resolution ultrasound projections offered by the Vevo 2100 system provides tremendous benefits for cancer screening. Researchers can now benefit from the combined high-resolution ultrasound and optical contrast ability of the Vevo® LAZR photoacoustic imaging system to achieve clear, deep, images in 2D and 3D for optimal in vivo visualization and quantification of internal anatomy, tumor tissue, and hemodynamics.
Photoacoustic Imaging with Coherent Light - Emmanuel BossySébastien Popoff
This document summarizes a presentation on photoacoustic imaging with coherent light. It discusses how photoacoustics can be used to image in optically scattering media by coupling light and ultrasound. Two approaches for photoacoustic image formation are described: reconstruction-free imaging using time-resolved signals and reconstruction-based tomography. Enhanced imaging techniques using speckle illumination and wavefront shaping are presented, including a photoacoustic transmission matrix approach that allows focusing light through scattering samples. Challenges and potential solutions for deep tissue imaging are also outlined.
Photoacoustic computed tomography uses laser-induced acoustic waves generated from light absorption in tissue to produce high-resolution images for biomedical applications. It takes advantage of both optical contrast from absorbing structures like blood vessels and acoustic resolution. The technique can be used to detect cancer, identify atherosclerotic plaque, and monitor hemodynamics. While it provides high resolution, photoacoustic tomography also poses an inverse problem in reconstructing images from acoustic signals.
This document provides an overview of the key components of photoacoustic spectrometry instrumentation. It discusses the light sources used, including lasers, lamps and arcs that emit across different wavelengths. A monochromator or filter is used to select the desired wavelength. Sample cells are designed for different physical states and have windows for light entry/exit. Detectors include microphones and piezoelectric transducers to convert the acoustic signal to an electrical signal for analysis. The document outlines the operation and advantages of different cell and detector types for measuring gaseous, liquid and solid samples.
The document discusses emerging optical imaging techniques for medical use, including endoscopy, optical coherence tomography (OCT), photoacoustic imaging, diffuse optical tomography, Raman spectroscopy, super-resolution microscopy, and terahertz tomography. It provides details on the principles and applications of these techniques. The document also describes new instrumentation under development, such as handheld OCT, enhanced endoscopy using light scattering spectroscopy, improved photoacoustic ultrasound imaging, transcutaneous Raman spectroscopy for diagnosing infections, and a molecular dynamics manipulator for repairing biomolecules.
Photoacoustic spectroscopy is a technique that detects the acoustic waves generated through the absorption of modulated electromagnetic radiation in a sample. It can be used to measure the absorption spectrum of both gases and condensed matter. The absorbed radiation is converted to heat, causing temperature and pressure fluctuations that can be detected by a microphone or piezoelectric transducer. This allows for highly sensitive detection of small absorbers. While it can analyze all phases of matter, photoacoustic spectroscopy has limitations for non-gaseous samples and requires the analyte to absorb the laser light used. It has applications in areas like trace gas analysis, textile dyes, and biomedical samples.
Photoacoustic spectroscopy involves modulating a light source and measuring the sound waves produced in the sample. [1] When light is absorbed by a sample, it causes excitation of molecules and heat is released upon relaxation. [2] This heating and cooling due to the modulated light produces pressure waves that can be detected to analyze the sample. [3] The modulation frequency is adjusted to avoid interference and maximize the signal intensity measured.
Medical Imaging: 8 Opportunities for technology entrepreneurs and investorsHealthstartup
There is tremendous opportunity currently to conduct advanced analysis of imaging data for diagnostic and treatment planning purposes, to combine imaging data from various sources and to share images for better medical collaboration. While medical imaging used to be the exclusive domain of large multinational medical devices companies, startups are entering the fray with software-based solutions and clever use of open-source or consumer-based technologies.
Ischemia - or the lack of blood supply to a tissue - and subsequent reperfusion induces physiological and biochemical changes in the affected tissue and is an important area of study since the damage that occurs as a result is clinically important in diabetes and stroke.
Development and Validation of a Combined Photoacoustic Micro-Ultrasound Syste...FUJIFILM VisualSonics Inc.
Photoacoustic (PA) Imaging can estimate the spatial distribution of oxygen saturation (sO2) and total hemoglobin concentration (HbT) in blood, and be co-registered with B-Mode ultrasound images of the surrounding anatomy. This study will focus on the development of a PA imaging mode on a commercially available array based micro-ultrasound (μUS) system that is capable of creating such images.
Application Brief: Tumor Microenvironment Imaging with Photoacoustic TechnologyFUJIFILM VisualSonics Inc.
Photoacoustics (PA) combines optical contrast with the high spatial resolution and deep tissue penetration offered by ultrasound. Such applications are especially beneficial for monitoring tumor development, measuring blood concentration changes within it, and quantifying networks of vasculature formation and carcinoma growth over time.
VisualSonics has introduced a revolutionary micro-ultrasound and photoacoustic imaging system that allows researchers to collect a plethora of important data over the lifespan of animals, thereby significantly reducing the number of animals needed.
1) Ruthenium-poloxamer nanoprobes were prepared by encapsulating the hydrophobic ruthenium dye [Ru(dpp)3]Cl2 in poloxamer 407 surfactant micelles, providing a simple method for aqueous solubilization.
2) Two-photon microscopy of a mouse brain in vivo was performed using the probes, demonstrating excellent imaging quality and contrast of the brain vasculature down to 100 μm resolution.
3) The probes showed good two-photon excitation properties, oxygen sensitivity through lifetime measurements, and stability, indicating potential for quantitative three-dimensional oxygen concentration mapping in tissues.
Investigating cellular metabolism with the 3D Cell ExplorerMathieuFRECHIN
The 3D Cell Explorer microscope allows for unprecedented live imaging of subcellular structures like mitochondria and lipid droplets due to its high spatiotemporal resolution and lack of phototoxicity. This enables long-term observation of organelle dynamics and interactions in an unperturbed state. Experiments demonstrated unique imaging of mitochondrial network perturbations and rescues as well as quantitative tracking of lipid droplet features over time. The system provides new opportunities to study metabolism at the subcellular level.
Using the 3D Cell Explorer-fluo for fluorescence and holotomographic imagingMathieuFRECHIN
Nanolive’s 3D Cell Explorer allows for the creation of very powerful 3D images and 4D time lapses
of living cells with very high spatio-temporal resolution (x,y:180nm; z:400nm; t:1.7sec). Moreover,
imaging with the 3D Cell Explorer does not require the use of any labels since the microscope directly
measures the refractive index of the different substructures of the cell. However, in the context of
molecular or cellular biology investigations, it can be useful to follow fluorescent markers combined
with the refractive index distribution to validate specific structures or to correlate fluorescent signals
and cellular states.
For this purpose, Nanolive developed the 3D Cell Explorer-fluo (https://nanolive.ch/fluo/) – a
complete solution that combines high precision tomographic data with high quality tri- or fourchannel
epifluorescence provided by a CoolLed module (https://www.coolled.com/).
In this application note we will present the time lapse imaging of mouse embryonic stem cells
(mESCs) that have been genetically modified to express the fluorescence ubiquitination cell cycle
indicator (FUCCI), a two-color (red and green) indicator that allows to monitor the cell cycle phases.
We will explain how to use the 3D Cell Explorer-fluo to record movies that require both fluorescence
and 3D refractive index imaging and will propose a solution to analyze the resulting time lapse
experiment.
This document provides a summary of the history and components of biosensors. It begins with a timeline of important developments in biosensor technology from 1962 to present day. It then defines what a biosensor is, including definitions from IUPAC. The key components of a biosensor are described as the biological recognition element, transducer, and associated electronics. Common biological elements and transducers used in biosensors are listed. The working principle is explained with diagrams. Applications of various types of biosensors are discussed, including those using enzymes, microorganisms, cells/tissues, organelles and bio-mimetic materials. Methods of immobilizing the biological recognition element are also summarized.
The document summarizes skeletal scintigraphy (bone scan) imaging. It describes how bone scan works by using radiotracers that localize to areas of bone formation/turnover. Technetium-99m methylene diphosphonate (Tc-99m MDP) is commonly used as it rapidly distributes to bone and is cleared from soft tissues. Imaging involves whole body scans 2-4 hours later to visualize bone abnormalities indicative of tumors, fractures or infections. Single photon emission computed tomography (SPECT) provides three-dimensional localization of lesions and improved specificity when fused to CT images. The distribution of uptake in normal bone changes with age and osteoarthritic changes are common benign findings.
This document describes how laser-induced breakdown spectroscopy (LIBS) was used to generate 3D elemental images of nanoparticle distribution in biological tissue at multiple scales. Sliced kidney tissue sections were mapped using LIBS to reconstruct the global nanoparticle distribution throughout the entire organ. Higher resolution LIBS imaging was also performed on specific regions of interest by repeatedly ablating the same tissue volume. This proof-of-concept study demonstrates that LIBS can quantitatively image both endogenous and exogenous elements in 3D within entire organs.
Near infrared spectroscopy for medical applications current status and future...skywalkerskywalker
This review discusses the use of near-infrared spectroscopy (NIRS) for medical applications. NIRS can be used to noninvasively measure oxygen levels in tissues due to NIR light's ability to penetrate the body. It has various applications including functional brain analysis, disease diagnosis, and monitoring of clinical laboratory tests. The review introduces recent advances in NIRS and its potential clinical uses such as measuring oxygen levels in the brain during tasks, detecting diseases, and analyzing biomolecules in the body.
This document discusses the use of fluorescent proteins in current biological research. It begins with an overview of the development of optical microscopy and fluorescence techniques. It then focuses on the green fluorescent protein (GFP) and how it has been used as a molecular tag to study protein expression and interactions in living cells through techniques like gene delivery, transfection, viral infection, FRET, and optogenetics. The document concludes that fluorescent proteins have revolutionized cell biology by enabling the real-time visualization and control of molecular pathways and signaling processes in living systems.
Fluorescence technique involves the optical detection and spectral analysis of light emitted by a substance undergoing a transition from an excited electronic state to a lower electronic state. The aim of this study is to assess the -amino levulinic acid (-ALA) uptake. Based on image processing technique, Matlab was used to analyze the fluorescence images resulted from activation of (-ALA) and follow its uptake along one week. Analyzing the RGB colours pixel profile from obtained results showed different profiles for malignant tissues, normal tissues, treated just after PDT and finally at one week post PDT. The treated tissues fluorescence profile showed changes from closer to malignant tissue profile till been closed to normal one.
1) Multi-photon microscopy was used to characterize the intrinsic fluorescence of sickle cell disease hemoglobin (HbS). HbS demonstrated broad emission around 510 nm when excited at 800 nm.
2) MPM was able to dynamically induce and image HbS gel formation through photolysis of deoxygenated HbS. Healthy hemoglobin (HbA) remained in solution and did not form fibers under the same conditions.
3) The intrinsic fluorescence of HbS fibers could enable the study of environmental factors that impact HbS polymerization and sickling of red blood cells, which is relevant for understanding sickle cell disease.
Reflectance spectroscopy uses light emitters and detectors to non-invasively monitor tissue oxygenation by measuring light absorption and scatter through tissue. Visible light spectroscopy (VLS) uses visible light for shallow penetration up to 16mm and is suitable for small volumes, while near infrared spectroscopy (NIRS) uses infrared light for deeper penetration of several cm and larger tissue volumes. These techniques are used clinically to monitor tissue oxygenation in various organs and procedures, particularly cerebral oxygenation monitored by NIRS probes on the forehead. Limitations include light attenuation from skin pigmentation affecting measured values.
This document discusses using imaging spectroscopy to estimate chlorophyll content in soybean leaves. It begins with an introduction to near infrared spectroscopy and its history. It then describes how a field imaging spectroscopy system was used to collect spectral data from soybean leaves. Random forests regression and the PROSPECT radiative transfer model were used to establish a model for estimating chlorophyll concentration from the spectral data. The model was able to accurately estimate chlorophyll content in soybean leaves and has potential applications for precision agriculture management and monitoring crop health at larger scales using remote sensing.
Photoacoustic computed tomography uses laser-induced acoustic waves generated from light absorption in tissue to produce high-resolution images for biomedical applications. It takes advantage of both optical contrast from absorbing structures like blood vessels and acoustic resolution. The technique can be used to detect cancer, identify atherosclerotic plaque, and monitor hemodynamics. While it provides high resolution, photoacoustic tomography also poses an inverse problem in reconstructing images from acoustic signals.
This document provides an overview of the key components of photoacoustic spectrometry instrumentation. It discusses the light sources used, including lasers, lamps and arcs that emit across different wavelengths. A monochromator or filter is used to select the desired wavelength. Sample cells are designed for different physical states and have windows for light entry/exit. Detectors include microphones and piezoelectric transducers to convert the acoustic signal to an electrical signal for analysis. The document outlines the operation and advantages of different cell and detector types for measuring gaseous, liquid and solid samples.
The document discusses emerging optical imaging techniques for medical use, including endoscopy, optical coherence tomography (OCT), photoacoustic imaging, diffuse optical tomography, Raman spectroscopy, super-resolution microscopy, and terahertz tomography. It provides details on the principles and applications of these techniques. The document also describes new instrumentation under development, such as handheld OCT, enhanced endoscopy using light scattering spectroscopy, improved photoacoustic ultrasound imaging, transcutaneous Raman spectroscopy for diagnosing infections, and a molecular dynamics manipulator for repairing biomolecules.
Photoacoustic spectroscopy is a technique that detects the acoustic waves generated through the absorption of modulated electromagnetic radiation in a sample. It can be used to measure the absorption spectrum of both gases and condensed matter. The absorbed radiation is converted to heat, causing temperature and pressure fluctuations that can be detected by a microphone or piezoelectric transducer. This allows for highly sensitive detection of small absorbers. While it can analyze all phases of matter, photoacoustic spectroscopy has limitations for non-gaseous samples and requires the analyte to absorb the laser light used. It has applications in areas like trace gas analysis, textile dyes, and biomedical samples.
Photoacoustic spectroscopy involves modulating a light source and measuring the sound waves produced in the sample. [1] When light is absorbed by a sample, it causes excitation of molecules and heat is released upon relaxation. [2] This heating and cooling due to the modulated light produces pressure waves that can be detected to analyze the sample. [3] The modulation frequency is adjusted to avoid interference and maximize the signal intensity measured.
Medical Imaging: 8 Opportunities for technology entrepreneurs and investorsHealthstartup
There is tremendous opportunity currently to conduct advanced analysis of imaging data for diagnostic and treatment planning purposes, to combine imaging data from various sources and to share images for better medical collaboration. While medical imaging used to be the exclusive domain of large multinational medical devices companies, startups are entering the fray with software-based solutions and clever use of open-source or consumer-based technologies.
Ischemia - or the lack of blood supply to a tissue - and subsequent reperfusion induces physiological and biochemical changes in the affected tissue and is an important area of study since the damage that occurs as a result is clinically important in diabetes and stroke.
Development and Validation of a Combined Photoacoustic Micro-Ultrasound Syste...FUJIFILM VisualSonics Inc.
Photoacoustic (PA) Imaging can estimate the spatial distribution of oxygen saturation (sO2) and total hemoglobin concentration (HbT) in blood, and be co-registered with B-Mode ultrasound images of the surrounding anatomy. This study will focus on the development of a PA imaging mode on a commercially available array based micro-ultrasound (μUS) system that is capable of creating such images.
Application Brief: Tumor Microenvironment Imaging with Photoacoustic TechnologyFUJIFILM VisualSonics Inc.
Photoacoustics (PA) combines optical contrast with the high spatial resolution and deep tissue penetration offered by ultrasound. Such applications are especially beneficial for monitoring tumor development, measuring blood concentration changes within it, and quantifying networks of vasculature formation and carcinoma growth over time.
VisualSonics has introduced a revolutionary micro-ultrasound and photoacoustic imaging system that allows researchers to collect a plethora of important data over the lifespan of animals, thereby significantly reducing the number of animals needed.
1) Ruthenium-poloxamer nanoprobes were prepared by encapsulating the hydrophobic ruthenium dye [Ru(dpp)3]Cl2 in poloxamer 407 surfactant micelles, providing a simple method for aqueous solubilization.
2) Two-photon microscopy of a mouse brain in vivo was performed using the probes, demonstrating excellent imaging quality and contrast of the brain vasculature down to 100 μm resolution.
3) The probes showed good two-photon excitation properties, oxygen sensitivity through lifetime measurements, and stability, indicating potential for quantitative three-dimensional oxygen concentration mapping in tissues.
Investigating cellular metabolism with the 3D Cell ExplorerMathieuFRECHIN
The 3D Cell Explorer microscope allows for unprecedented live imaging of subcellular structures like mitochondria and lipid droplets due to its high spatiotemporal resolution and lack of phototoxicity. This enables long-term observation of organelle dynamics and interactions in an unperturbed state. Experiments demonstrated unique imaging of mitochondrial network perturbations and rescues as well as quantitative tracking of lipid droplet features over time. The system provides new opportunities to study metabolism at the subcellular level.
Using the 3D Cell Explorer-fluo for fluorescence and holotomographic imagingMathieuFRECHIN
Nanolive’s 3D Cell Explorer allows for the creation of very powerful 3D images and 4D time lapses
of living cells with very high spatio-temporal resolution (x,y:180nm; z:400nm; t:1.7sec). Moreover,
imaging with the 3D Cell Explorer does not require the use of any labels since the microscope directly
measures the refractive index of the different substructures of the cell. However, in the context of
molecular or cellular biology investigations, it can be useful to follow fluorescent markers combined
with the refractive index distribution to validate specific structures or to correlate fluorescent signals
and cellular states.
For this purpose, Nanolive developed the 3D Cell Explorer-fluo (https://nanolive.ch/fluo/) – a
complete solution that combines high precision tomographic data with high quality tri- or fourchannel
epifluorescence provided by a CoolLed module (https://www.coolled.com/).
In this application note we will present the time lapse imaging of mouse embryonic stem cells
(mESCs) that have been genetically modified to express the fluorescence ubiquitination cell cycle
indicator (FUCCI), a two-color (red and green) indicator that allows to monitor the cell cycle phases.
We will explain how to use the 3D Cell Explorer-fluo to record movies that require both fluorescence
and 3D refractive index imaging and will propose a solution to analyze the resulting time lapse
experiment.
This document provides a summary of the history and components of biosensors. It begins with a timeline of important developments in biosensor technology from 1962 to present day. It then defines what a biosensor is, including definitions from IUPAC. The key components of a biosensor are described as the biological recognition element, transducer, and associated electronics. Common biological elements and transducers used in biosensors are listed. The working principle is explained with diagrams. Applications of various types of biosensors are discussed, including those using enzymes, microorganisms, cells/tissues, organelles and bio-mimetic materials. Methods of immobilizing the biological recognition element are also summarized.
The document summarizes skeletal scintigraphy (bone scan) imaging. It describes how bone scan works by using radiotracers that localize to areas of bone formation/turnover. Technetium-99m methylene diphosphonate (Tc-99m MDP) is commonly used as it rapidly distributes to bone and is cleared from soft tissues. Imaging involves whole body scans 2-4 hours later to visualize bone abnormalities indicative of tumors, fractures or infections. Single photon emission computed tomography (SPECT) provides three-dimensional localization of lesions and improved specificity when fused to CT images. The distribution of uptake in normal bone changes with age and osteoarthritic changes are common benign findings.
This document describes how laser-induced breakdown spectroscopy (LIBS) was used to generate 3D elemental images of nanoparticle distribution in biological tissue at multiple scales. Sliced kidney tissue sections were mapped using LIBS to reconstruct the global nanoparticle distribution throughout the entire organ. Higher resolution LIBS imaging was also performed on specific regions of interest by repeatedly ablating the same tissue volume. This proof-of-concept study demonstrates that LIBS can quantitatively image both endogenous and exogenous elements in 3D within entire organs.
Near infrared spectroscopy for medical applications current status and future...skywalkerskywalker
This review discusses the use of near-infrared spectroscopy (NIRS) for medical applications. NIRS can be used to noninvasively measure oxygen levels in tissues due to NIR light's ability to penetrate the body. It has various applications including functional brain analysis, disease diagnosis, and monitoring of clinical laboratory tests. The review introduces recent advances in NIRS and its potential clinical uses such as measuring oxygen levels in the brain during tasks, detecting diseases, and analyzing biomolecules in the body.
This document discusses the use of fluorescent proteins in current biological research. It begins with an overview of the development of optical microscopy and fluorescence techniques. It then focuses on the green fluorescent protein (GFP) and how it has been used as a molecular tag to study protein expression and interactions in living cells through techniques like gene delivery, transfection, viral infection, FRET, and optogenetics. The document concludes that fluorescent proteins have revolutionized cell biology by enabling the real-time visualization and control of molecular pathways and signaling processes in living systems.
Fluorescence technique involves the optical detection and spectral analysis of light emitted by a substance undergoing a transition from an excited electronic state to a lower electronic state. The aim of this study is to assess the -amino levulinic acid (-ALA) uptake. Based on image processing technique, Matlab was used to analyze the fluorescence images resulted from activation of (-ALA) and follow its uptake along one week. Analyzing the RGB colours pixel profile from obtained results showed different profiles for malignant tissues, normal tissues, treated just after PDT and finally at one week post PDT. The treated tissues fluorescence profile showed changes from closer to malignant tissue profile till been closed to normal one.
1) Multi-photon microscopy was used to characterize the intrinsic fluorescence of sickle cell disease hemoglobin (HbS). HbS demonstrated broad emission around 510 nm when excited at 800 nm.
2) MPM was able to dynamically induce and image HbS gel formation through photolysis of deoxygenated HbS. Healthy hemoglobin (HbA) remained in solution and did not form fibers under the same conditions.
3) The intrinsic fluorescence of HbS fibers could enable the study of environmental factors that impact HbS polymerization and sickling of red blood cells, which is relevant for understanding sickle cell disease.
Reflectance spectroscopy uses light emitters and detectors to non-invasively monitor tissue oxygenation by measuring light absorption and scatter through tissue. Visible light spectroscopy (VLS) uses visible light for shallow penetration up to 16mm and is suitable for small volumes, while near infrared spectroscopy (NIRS) uses infrared light for deeper penetration of several cm and larger tissue volumes. These techniques are used clinically to monitor tissue oxygenation in various organs and procedures, particularly cerebral oxygenation monitored by NIRS probes on the forehead. Limitations include light attenuation from skin pigmentation affecting measured values.
This document discusses using imaging spectroscopy to estimate chlorophyll content in soybean leaves. It begins with an introduction to near infrared spectroscopy and its history. It then describes how a field imaging spectroscopy system was used to collect spectral data from soybean leaves. Random forests regression and the PROSPECT radiative transfer model were used to establish a model for estimating chlorophyll concentration from the spectral data. The model was able to accurately estimate chlorophyll content in soybean leaves and has potential applications for precision agriculture management and monitoring crop health at larger scales using remote sensing.
Old age people and kindergarten children face health problems mainly due to deficiencies in sanitation. So
a complete wireless health monitoring system which continuously monitors some of the vital body
parameters such as body temperature, heart pulse rate, motion sensor and odour sensor can be designed.
Our paper deals with the detection of ammonia (NH3) and hydrogen sulphide (H2S) using an odour sensor
or a gas sensor.
ODOUR SENSOR BASED SOLUTION FOR THE SANITARY PROBLEM FACED BY ELDERLY PEOPLE ...ijistjournal
Old age people and kindergarten children face health problems mainly due to deficiencies in sanitation. So a complete wireless health monitoring system which continuously monitors some of the vital body parameters such as body temperature, heart pulse rate, motion sensor and odour sensor can be designed. Our paper deals with the detection of ammonia (NH3) and hydrogen sulphide (H2S) using an odour sensor or a gas sensor.
OCT provides high-resolution cross-sectional images of ocular structures. There are various types including time-domain OCT, spectral-domain OCT, and swept-source OCT. AS-OCT allows non-invasive imaging of the anterior segment at high speed. It is useful for imaging corneal thickness, lesions, infections, dystrophies, and deposits. AS-OCT also provides pre- and post-operative evaluation and measurement of procedures such as LASIK, DSEK, and intracorneal ring segments.
A biosensor is a device that integrates a biological component with a physicochemical detector. There are three main components: the biological recognition element, transducer, and associated electronics. The biological element interacts selectively with the analyte. The transducer converts this interaction into a quantifiable signal like a current or voltage. The associated electronics then process and display the results. Common types of biosensors include electrochemical, optical, and ion channel switch biosensors which detect analytes through electrochemical reactions, light interactions, or ion flow respectively.
Similar to Application Brief: Imaging Oxygen Saturation with Photoacoustic Technology (20)
This document describes a high resolution multi-modal imaging platform that combines ultrasound and photoacoustics. It provides anatomical, functional, and molecular data with superior resolution down to 30 μm. The system has a customizable touchscreen interface and is compact and portable. It can be used for applications in neurobiology, molecular biology, cardiology, and oncology to assess vascularity, perfusion, biomarkers, and response to therapy.
Vevo 3100 - The ultimate preclinical imaging experience. The Vevo 3100 is a new and innovative platform created for the future of imaging. It combines ultra high frequency ultrasound imaging, quantification and education in a convenient all-in-one touchscreen platform.
This document provides a bibliography of top cardiovascular research papers organized by topic. The topics covered include abdominal aortic aneurysm, atherosclerosis, cardiac hypertrophy, cardiac injection, cardiomyopathy, chick embryo, contrast, developmental cardiology, diastolic dysfunction, graft transplantation, Holt-Oram syndrome, Marfan syndrome, myocardial infarction, pulmonary hypertension, rabbit cardiovascular, rat cardiovascular, stem cells, stress echocardiography, and valvular flow & function. For each topic, several of the most influential papers from 2009-2010 are listed with their citation information.
This document provides a bibliography of research papers related to cancer organized by topic. It includes 3-7 references for each of 17 cancer-related topics, such as 3D tumor imaging, angiogenesis, bladder cancer, breast cancer, contrast imaging, and others. The references provided for each topic are journal articles published between 2005-2010 that describe research on imaging, molecular markers, treatment responses, and other aspects of various cancers.
This document provides a bibliography of top nephrology research papers from 2010 and earlier, focusing on topics related to polycystic kidney disease, acute kidney injury, fibrosis, cyst formation, glomerular disease, target organ damage, regional blood flow in the mouse kidney, renal ischemia, phosphate homeostasis, aortic valve calcification in rats, kidney safety in drug development, imaging the kidney with ultrasound, changes to lymphatic and blood vessel architecture from transgenic expression of Angiopoietin 1 in the liver, and a functional floxed allele of Pkd1 that can be conditionally inactivated in vivo. The bibliography contains 20 research papers published between 2004 and 2010.
This document provides a protocol for imaging the deep brain of freely moving mice. It describes:
1) Implanting a guide cannula into the mouse skull to access the brain region of interest. This involves drilling holes, inserting screws, and cementing the cannula in place.
2) Precisely positioning the cannula using stereotactic coordinates to target a specific brain structure.
3) Inserting the cannula 300-600 micrometers into the brain depending on the target depth.
Tumor angiogenesis is currently one of the key focal points in biomedical research. It is based upon the hypothesis laid out by Judah Folkman in 1971 that neovasculature is needed to support the growth and metastasis of tumors, and thus anti-angiogenic treatment might be an effective way to cure cancer. Genentech’s anti-VEGF-A drug Avastin a great demonstration of this concept, generating more than $2.7 billion of sales in 2008.
Breast cancer research in animal models has long been hindered by the lack of a fast, portable, high resolution, research and animal focused imaging system that can visualize 2D tumor size, 3D tumor volume, neoangiogenesis and blood perfusion in vivo, in real-time and most importantly, non-invasively.
White Paper: In vivo Fiberoptic Fluorescence Microscopy in freely behaving miceFUJIFILM VisualSonics Inc.
Fiberoptic fluorescence microscopy (FFM) employs optical fibers as small as 300 micrometers in diameter and offers the ability to image cellular and subcellular processes in deep brain structures including the Ventral Tegmental Area (VTA) and the substantia nigra (Sn).
1. The document describes the Vevo 2100 imaging platform from VisualSonics, which redefines preclinical ultrasound imaging with high resolution, advanced functionality, and quantitative analysis capabilities.
2. It can image a wide range of animal models from embryos to adults, provides anatomical, functional and molecular data non-invasively, and has applications across many research areas.
3. The system offers superior resolution, color and power Doppler, 3D imaging, advanced measurements, and is easy to use with one-button presets and analysis software.
Radiotherapy and chemotherapy aim at killing tumor cells or at least stopping their multiplication. Those therapies have strong limitations: first, their inherent toxicity is not limited to tumoral cells, but also affects healthy tissue; second, only the strongest and most resistant tumoral cells are able to survive, leading to increasingly aggressive tumors.
The document compares the features of the Vevo 2100 and Vevo 770 ultrasound systems, noting that the Vevo 2100 has improved high frequency transducers, multiple focal zones, higher frame rates, access to raw RF data export, improved non-linear contrast and power Doppler imaging, and faster 3D imaging compared to the Vevo 770. The Vevo 2100 also has new features like VevoStrain, color Doppler, simultaneous dual mode viewing, steerable Doppler, ECG-gating, and rabbit imaging that are not available on the Vevo 770.
The document compares the features of the Vevo 2100 and Vevo 770 ultrasound systems, noting that the Vevo 2100 has improved high frequency transducers, multiple focal zones, higher frame rates, access to raw RF data export, improved non-linear contrast and power Doppler imaging, and faster 3D imaging compared to the Vevo 770. The Vevo 2100 also has new features like VevoStrain, color Doppler, simultaneous dual mode viewing, steerable Doppler, ECG-gating, and rabbit imaging that are not available on the Vevo 770.
This 3-sentence summary provides the key details about the protocol:
The protocol describes how to implant a guide cannula in transgenic mice expressing fluorescent proteins to allow insertion of a fiber optic probe for imaging deep brain structures of freely moving mice under anesthesia. The guide cannula is implanted using stereotactic surgery and then a fiber optic probe is inserted through the cannula and lowered to the target brain region under microscope guidance for in vivo imaging of fluorescent cells over multiple time points.
In this application, Cellvizio was used to study the neuronal degeneration and regeneration processes in live, anaesthetized, adult Thy1-YFP transgenic mice.
Abdominal Aortic Aneurysm (AAA) is a serious and potentially fatal disease that is prevalent in the older population. Scientists are making use of animal models to study the progression of this disease and the effects of therapeutic interventions over longitudinal studies.
This document discusses the need for improved imaging systems for breast cancer research using animal models. It introduces a new micro-ultrasound system that allows researchers to non-invasively collect longitudinal data on tumor size, volume, vascularity and perfusion over an animal's lifespan. This significantly reduces the number of animals needed for research. The system has been adopted by leading cancer research institutions and numerous studies have been published demonstrating its ability to accurately track tumor growth and response to therapies.
This document summarizes an application brief about using micro-ultrasound to study cancer angiogenesis. It discusses how micro-ultrasound allows researchers to non-invasively visualize 3D tumor volume, neoangiogenesis, and blood perfusion over time in small animal models. This helps researchers better understand cancer development and anti-angiogenic therapies. VisualSonics' micro-ultrasound systems provide high resolution real-time imaging of tumor growth and vascularity to help reduce the number of animals needed for research.
[OReilly Superstream] Occupy the Space: A grassroots guide to engineering (an...Jason Yip
The typical problem in product engineering is not bad strategy, so much as “no strategy”. This leads to confusion, lack of motivation, and incoherent action. The next time you look for a strategy and find an empty space, instead of waiting for it to be filled, I will show you how to fill it in yourself. If you’re wrong, it forces a correction. If you’re right, it helps create focus. I’ll share how I’ve approached this in the past, both what works and lessons for what didn’t work so well.
Ivanti’s Patch Tuesday breakdown goes beyond patching your applications and brings you the intelligence and guidance needed to prioritize where to focus your attention first. Catch early analysis on our Ivanti blog, then join industry expert Chris Goettl for the Patch Tuesday Webinar Event. There we’ll do a deep dive into each of the bulletins and give guidance on the risks associated with the newly-identified vulnerabilities.
Dandelion Hashtable: beyond billion requests per second on a commodity serverAntonios Katsarakis
This slide deck presents DLHT, a concurrent in-memory hashtable. Despite efforts to optimize hashtables, that go as far as sacrificing core functionality, state-of-the-art designs still incur multiple memory accesses per request and block request processing in three cases. First, most hashtables block while waiting for data to be retrieved from memory. Second, open-addressing designs, which represent the current state-of-the-art, either cannot free index slots on deletes or must block all requests to do so. Third, index resizes block every request until all objects are copied to the new index. Defying folklore wisdom, DLHT forgoes open-addressing and adopts a fully-featured and memory-aware closed-addressing design based on bounded cache-line-chaining. This design offers lock-free index operations and deletes that free slots instantly, (2) completes most requests with a single memory access, (3) utilizes software prefetching to hide memory latencies, and (4) employs a novel non-blocking and parallel resizing. In a commodity server and a memory-resident workload, DLHT surpasses 1.6B requests per second and provides 3.5x (12x) the throughput of the state-of-the-art closed-addressing (open-addressing) resizable hashtable on Gets (Deletes).
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Introduction of Cybersecurity with OSS at Code Europe 2024Hiroshi SHIBATA
I develop the Ruby programming language, RubyGems, and Bundler, which are package managers for Ruby. Today, I will introduce how to enhance the security of your application using open-source software (OSS) examples from Ruby and RubyGems.
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Have you ever been confused by the myriad of choices offered by AWS for hosting a website or an API?
Lambda, Elastic Beanstalk, Lightsail, Amplify, S3 (and more!) can each host websites + APIs. But which one should we choose?
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This presentation delves into the development of a system designed to mimic Galileo's Open Service signal using software-defined radio (SDR) technology. We'll begin with a foundational overview of both Global Navigation Satellite Systems (GNSS) and the intricacies of digital signal processing.
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For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/temporal-event-neural-networks-a-more-efficient-alternative-to-the-transformer-a-presentation-from-brainchip/
Chris Jones, Director of Product Management at BrainChip , presents the “Temporal Event Neural Networks: A More Efficient Alternative to the Transformer” tutorial at the May 2024 Embedded Vision Summit.
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zkStudyClub - LatticeFold: A Lattice-based Folding Scheme and its Application...Alex Pruden
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Paper Link: https://eprint.iacr.org/2024/257
Application Brief: Imaging Oxygen Saturation with Photoacoustic Technology
1. Application Brief: Imaging Oxygen Saturation with Photoacoustic
Technology
Executive Summary
Oxygen saturation (sO2) is a measure of the amount of hemoglobin binding sites occupied
by oxygen and is expressed as a percentage value of total binding sites. Oxygen saturation
measurements have important therapeutic applications in widespread clinical use. In humans, low
sO2 levels in tissues could indicate a hypoxic environment, permitting tumor proliferation, inhibiting
tissue perfusion or even indicating the presence of necrotizing fasciitis (Lima et al., 2009; Wang et
al., 2004). Furthermore, sO2 measurements can provide information on anemia, fetal development,
and ischemia/stroke.
The main sO2 measurement modalities currently used for quantification within a tissue are
pimonidazole staining, glucose transporter-1 (Glut-1) staining, and O2 microelectrode
measurements. The invasiveness of O2 microelectrode measurements makes this modality less
than ideal for determining sO2 within a tissue, especially since the needle electrodes must be
inserted subdermally Furthermore, the hypoxic tissue must be accessible to the needle to assess
oxygenation status, limiting its use to tissues close to the skin surface.
Pimonidazole is a reductively activated drug marker for hypoxia, which binds covalently to
thiol-containing proteins within hypoxic cells and forms intracellular adducts (Coer et al., 2007). It
must be administered to the tissue of interest prospectively (~16 hours prior to excision), is
extremely invasive and cannot be used on studies of archival tissues. Glut-1 is a protein
upregulated in response to hypoxic conditions through the hypoxia inducible factor-1 (HIF-1)
pathway, making it an ideal endogenous marker for low sO2 (Coer et al., 2007). Glut-1 expression
staining holds the advantage of being detectable on retrospectively-obtained tissues and does not
require drug-binding. For both pimonidazole and Glut-1 staining, areas containing positive staining
are quantified immunohistochemically on excised tissue sections.
An indirect method of measuring sO2 is pulse oximetry, whereby readings are recorded by a
sensor placed on a thin anatomical point (ie. earlobe or fingertip). A photosensor detects light
passing through a tissue and determines the percentage of oxygenated to total hemoglobin based
on the differential absorption characteristics of oxyhemoglobin and deoxyhemoglobin. Pulse
oximetry has been used for diagnosing cyanosis, dyspnea and tachypnea (Schutz and Saunders.,
2001). However, it is limited by accuracy-inhibiting factors, such as; decreased peripheral pulses,
body temperature and blood pressure.
Application Brief: Imaging sO2 with Photoacoustic Technology 1
January 2011 Ver 1.3
2. All the methods outlined for measuring oxygen saturation have some advantages but confer
significant disadvantages. Among them, the user cannot determine the sO2 at a specific anatomical
point, or visualize where the signal is coming from. With high-frequency ultrasound, the user has
the ability to view the internal mammalian anatomy in a non-invasive fashion. When combining the
high spatial resolution and deep tissue penetration offered by ultrasound with the optical contrast
of photoacoustic laser technology, sO2 can be measured precisely, non-invasively and in real-time
while the user can see exactly where the signal
is coming from within a tissue. Photoacoustics
(PA) can measure sO2 in deep tissues by
placing external probes on the skin surface and
scanning. This technology works in a manner
similar to pulse oximetry, by exploiting the
differential light absorption spectra of
hemoglobin. However, the cursor can sample
the percentage value of oxygenation anywhere
within the image of the tissue under study with
high sensitivity and anatomical specificity. Not
only does photoacoustics increase the areas
amenable to study, but it also displays an Figure 1 – Mouse hindlimb tumor visualized
oxygen saturation map across the tissue at 40 MHz indicating hypoxic conditions. The
landscape to visually discern the sO2 status sampled area has an sO2 of 31%.
(Figure 1). The linear transducer array
technology enables co-registration of both ultrasound and photoacoustic modalities in 2D or 3D,
allowing for studies of anatomical structures and the functional parameters within them.
Background on sO2 Imaging Possibilities with Photoacoustics
Oxygenation status can be achieved across multiple tissues and organs with the help of the
Vevo® LAZR photoacoustics imaging system. Designed for preclinical imaging in small mammalian
systems such as rats, mice and rabbits, the Vevo LAZR platform is capable of visualizing sO2 in
many tissues and organs including testicle, brain, tumors, embryo and muscle.
The Vevo LAZR software allows for the acquisition of photoacoustic images to detect the
presence of hemoglobin and other absorbers, and co-register it with 2Dultrasound images. The
wavelength of the pulsed laser light used to generate the photoacoustic effect can be changed
anywhere from 680 nm to 970 nm. Images are acquired using ‘Oxyhemo’ mode, which collects
data at 750 and 850 nm and creates and displays a parametric map of estimated oxygen saturation
at a rate of 0.5 Hz. To analyze hemodynamics, the HemoMeaZure and OxyZated tools of the
Vevo LAZR platform are used to measure hemoglobin content and sO2 respectively.
Rather than viewing data as a linear output of numbers via pulse oximetry, the Vevo LAZR
photoacoustic imaging system offers the ability to see an in vivo map of oxygen saturation. Figure
2 shows an image of a mouse testicle under two oxygenation conditions – at 100% and 5% O2
inhalation .
Application Brief: Imaging sO2 with Photoacoustic Technology 2
January 2011 Ver 1.3
3. a b
Figure 2 – Real-time oxygen saturation in vivo in a mouse testicle at (a) 100% O2 inhalation and
(b) 5% O2 inhalation.
Similar conditions are easily visualized within a mouse brain breathing 100% and 21% O2 in
Figure 3, a and b, respectively. These images also illustrate the ability to average the sO2 within a
specific area of the tissue, which in this case reached 92% oxygenation when the animal was
breathing 100% O2 and 76% when it was breathing room air.
a b
Figure 3 – Images of the mouse brain with a partial craniotomy. Oxyhemo measurements are
taken in a brain region while the animal is breathing (a) 100% O2 (92% oxygenation) or (b) room
air (76% oxygenation).
The brain can also be visualized through an intact skull with an imaging depth of ~3.5mm
(see sO2 Application Note).
Induction of ischemia and subsequent reperfusion in the mouse hindlimb generates
dramatic visible changes in sO2 with the Vevo LAZR platform, as shown in Figure 4.
a b c
Figure 4 – Oxyhemo image with 2D2D overlay of the mouse hindlimb under (a) non-ischemic, (b)
ischemic and (c) reperfused conditions.
Application Brief: Imaging sO2 with Photoacoustic Technology 3
January 2011 Ver 1.3
4. a b
Figure 5 – 3D images of the hindlimb of a mouse showing (a) ischemic conditions and (b) sO2
reperfusion.
Pre-ischemic, ischemic and reperfused tissues show varying degrees of oxygenation. These
conditions can also be displayed in a 3D rendering by the Vevo LAZR platform, as shown in
Figure 5.
In studies of tumor and embryo development, photoacoustica offers the ability to monitor
hemodynamics in vivo and in real-time. Moreover, the imaging is completely safe and non-
invasive, and will not harm the embryo. The tumor microenvironment will also be preserved,
allowing for longitudinal studies to be performed. Photoacoustic imaging with sO2 mapping in the
tumor and embryo is shown in Figure 6.
a b
Figure 6 – (a) Photoacoustic oxygenation map superimposed on a 2D image of a subcutaneous
tumor and (b) Oxyhemo image of an ~E18 intact embryo with LZ250 showing depth of various
signals to a max depth of 7.5 mm
Maternal blood oxygenation levels can also be measured within the placenta when studying
hemodynamics in the embryo. Tumors can be easily detected early on within tissues based on their
highly disorganized formations of neovasculature, which absorb the illuminated pulsed laser light at
much higher levels. The 2D registration renders rapid information about its location based on its
increased hemoglobin count, which acts as an endogenous signal for photoacoustics.
Application Brief: Imaging sO2 with Photoacoustic Technology 4
January 2011 Ver 1.3
5. VisualSonics’ Value Proposition
sO2 measurements have in the past been limited to invasive, immunohistochemical, drug-
induced, surface sensor or molecular assay detection methods. These modalities, however, are
incomplete. Those which allow visualization of the tissue oxygenation status, such as pimonidazole
and Glut-1 staining, are invasive and require excision, which inhibits longitudinal studies. Those
which offer real-time monitoring, such as pulse oximetry, are non-visual and limited only to
superficial or very shallow subdermal anatomy. Pulse oximetry cannot detect tumors if their
position is not already known, and will provide sO2 values but will not source their location on
parametric map of the tissue under study. They are also subject to variables such as blood
pressure, circulation and peripheral cyanosis (Schutz and Saunders, 2001).
The Vevo LAZR photoacoustic imaging system combines anatomical and functional information of
the tissue being imaged to address the shortcomings of current sO2 measurement methods. It
seeks to address the needs of researchers aiming to obtain quick, accurate and visually-mapped
imaging information on oxygen saturation across a variety of tissues to assess a variety of
conditions. This document has shown photoacoustic imaging with the Vevo LAZR platform in
testicular glands, embryos, tumors, hindlimbs and brain. Within these tissues, conditions of
ischemia, anemia, hypoxia, and reperfusion (among others) can be discerned with photoacoustic
imaging. The imaging is precise, non-invasive, anatomically localized and conducted in real-time.
Below is a summary of the unique value proposition VisualSonics delivers to researchers with the
Vevo LAZR photoacoustic imaging system for oxygen saturation quantification:
1. Inherent co-registration of the oxygen saturation signal and the 2D anatomical image.
2. High specificity via the use of the endogenous heme signal for detecting location and
oxygen saturation level of blood within anatomical structures.
3. Real-time visualization permits quick rendering and longitudinal monitoring studies for
embryo development, maternal blood oxygenation levels and tumor development.
4. Endogenous photoacoustic signal tools HemoMeaZure and OxyZated measure hemoglobin
content and oxygen saturation, respectively, without the use of contrast agents.
HemoMeaZure aids in assessment of anemia, while the OxyZated tool evaluates tumor and
tissue hypoxia.
5. Live 2D and 3D imaging for tissue morphology, vasculature mapping and oxygen saturation
measurements.
6. LAZRTight enclosure ensures optimal safety for the operator, and consists of physiological
monitoring, integrated anesthesia, transducer mounting system, 3D image controller, and
microinjection system ensures efficient and reproducible imaging.
Application Brief: Imaging sO2 with Photoacoustic Technology 5
January 2011 Ver 1.3
6. Bibliography
Alexandre Lima, Jasper van Bommel, Tim C Jansen, Can Ince and Jan Bakker. Low tissue oxygen
saturation at the end of early goal-directed therapy is associated with worse outcome in critically ill
patients. Critical Care 2009, 13(Suppl 5):S13
Coer A, Legan M, Stiblar-Martincic D, Cemazar M and Sersa G. Comparison of two hypoxic
markers: pimonidazole and glucose transporter 1 (Glut-1). IFMBE Proceedings, 2007, 16(13),
465-468.
Wang TL, Hung CR. Role of tissue oxygen saturation monitoring in diagnosing necrotizing fasciitis
of the lower limbs. Ann Emerg Med. 2004 Sep; 44(3):222-8.
Schutz SL and Sanders WB. Oxygen saturation monitoring by pulse oximetry. AACN Procedure
Manual for Critical Care, 2001, 4th Ed.
sO2 Application Note.
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January 2011 Ver 1.3