Category Ranking
98%
Total Visits
921
Avg Visit Duration
2 minutes
Citations
20
Article Abstract
Microvasculature hemoglobin oxygen saturation (SaO2) is important in the progression of various pathologies. Non-invasive depth-resolved measurement of SaO2 levels in tissue microvasculature has the potential to provide early biomarkers and a better understanding of the pathophysiological processes allowing improved diagnostics and prediction of disease progression. We report proof-of-concept in vivo depth-resolved measurement of SaO(2) levels in selected 30 µm diameter arterioles in the murine brain using Dual-Wavelength Photothermal (DWP) Optical Coherence Tomography (OCT) with 800 nm and 770 nm photothermal excitation wavelengths. Depth location of back-reflected light from a target arteriole was confirmed using Doppler and speckle contrast OCT images. SaO(2) measured in a murine arteriole with DWP-OCT is linearly correlated (R(2)=0.98) with systemic SaO(2) values recorded by a pulse-oximeter. DWP-OCT are steadily lower (10.1%) than systemic SaO(2) values except during pure oxygen breathing. DWP-OCT is insensitive to OCT intensity variations and is a candidate approach for in vivo depth-resolved quantitative imaging of microvascular SaO(2) levels.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3482904 | PMC |
| http://dx.doi.org/10.1364/OE.19.023831 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Water, Collagen, and Lipid Content in the Human Skin and Muscles Assessed with Near-Infrared Diffuse Reflectance Spectroscopy and Multi-Spectral Optoacoustic Tomography.
Adv Sci (Weinh)
August 2025
Faculty of Рhysics, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.
Infrared spectroscopy can quantify individual body components such as lipids, water, and proteins, but extending it to a comprehensive assessment of overall body composition is hampered by high variability and optical heterogeneity of biological tissues. Here, a theoretical and experimental strategy merging multi-spectral optoacoustic tomography (MSOT) and diffuse reflectance spectroscopy (DRS) is introduced to characterize skin and subcutaneous tissue composition in the near-infrared range. Water, lipids, and collagen exhibit distinct absorption peaks, with lipids demonstrating significantly higher absorption than collagen at comparable mass concentrations.
View Article and Find Full Text PDFCatheter-based polarimetric imaging to complement MRI for deep brain stimulation neurosurgery.
Neurophotonics
July 2025
Université Laval, CERVO Brain Research Center, Québec, Canada.
Significance: Deep brain stimulation (DBS) is an established treatment for movement disorders and other neurological conditions. Accurate localization of small deep brain nuclei, such as the subthalamic nucleus (STN) and internal pallidum (GPi), is crucial for successful DBS outcomes. However, magnetic resonance imaging (MRI), commonly used for DBS planning, lacks the resolution and contrast needed to directly delineate these target structures.
View Article and Find Full Text PDFOptical Coherence Tomography Enables the Depth-Resolved Measurement of Cilia Beat Frequency in Ex Vivo Human Fallopian Tubes.
Lasers Surg Med
September 2025
Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona, USA.
Objectives: The movement of cilia in the fallopian tubes (FTs) facilitates important processes involved in fertility, and abnormalities in cilia function are linked with diseases including endometriosis and pelvic inflammatory disease. For the first time, we demonstrate the use of optical coherence tomography (OCT) to create depth-resolved mapping of motile cilia locations and quantify cilia beat frequency (CBF) in human FT samples ex vivo.
Methods: Segments of the FT ampulla were acquired from five patients following salpingectomy under an IRB approved protocol.
Depth-Resolved Macroscopic Fluorescence Lifetime Imaging via High-Spatial-Frequency Structured Illumination.
bioRxiv
June 2025
Center for modeling, simulation and Imaging in Medicine, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
Significance: Macroscopic Fluorescence Lifetime Imaging (MFLI) is a powerful, non-invasive imaging modality that offers robust, physiologically relevant contrast largely independent of fluorophore concentration, excitation intensity, and tissue signal attenuation. However, accurately determining the depth of signal origin remains challenging, potentially leading to ambiguity in biological interpretation. Here, we present a novel optical correction method that effectively eliminates surface signal bias, such as that from skin in preclinical imaging, without the need for chemical clearance.
View Article and Find Full Text PDFUltrasensitive in vivo infrared spectroscopic imaging via oblique photothermal microscopy.
Nat Commun
July 2025
Department of Electrical and Computer Engineering, Boston University, Boston, MA, USA.
In vivo IR spectroscopy faces challenges due to poor sensitivity in reflection mode and low resolution at micrometer scale. To break this barrier, we report an oblique photothermal microscope (OPTM) to enable ultrasensitive IR spectroscopic imaging of live subjects at sub-micron resolution. Classic photothermal measurement captures only a small fraction of probe photons through an iris to extract the photothermal signal.
View Article and Find Full Text PDF