We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
LGC Clinical Diagnostics

Download Mobile App




Photoacoustic Microscopy Enables Rapid Imaging of the Brain's Oxygen Metabolism

By LabMedica International staff writers
Posted on 12 Apr 2015
Print article
Image: Fast functional photoacoustic microscopy of the mouse brain. Figure (d) shows a representative x-y projected brain vasculature image through an intact skull. Figure (e) shows a representative enhanced x-z projected brain vasculature image. Figure (f) shows photoacoustic microscopy of oxygen saturation of hemoglobin in the mouse brain, acquired by using the single-wavelength pulse-width-based method with two lasers (Photo courtesy of Washington University).
Image: Fast functional photoacoustic microscopy of the mouse brain. Figure (d) shows a representative x-y projected brain vasculature image through an intact skull. Figure (e) shows a representative enhanced x-z projected brain vasculature image. Figure (f) shows photoacoustic microscopy of oxygen saturation of hemoglobin in the mouse brain, acquired by using the single-wavelength pulse-width-based method with two lasers (Photo courtesy of Washington University).
Photoacoustic microscopy (PAM) is a novel imaging technique that was exploited by researchers to view the vascular morphology, blood oxygenation, blood flow, and oxygen metabolism in both resting and stimulated states in the mouse brain.

In PAM, non-ionizing laser pulses are delivered into biological tissues. Some of the delivered energy is absorbed and converted into heat, leading to transient thermoelastic expansion and wideband ultrasonic emission. The generated ultrasonic waves are detected by ultrasonic transducers and then analyzed to produce images. Optical absorption is closely associated with physiological properties, such as hemoglobin concentration and oxygen saturation. As a result, the magnitude of the ultrasonic emission (photoacoustic signal), which is proportional to the local energy deposition, reveals physiologically specific optical absorption contrast. Two-dimensional or three-dimensional images of the targeted areas can then be formed.

Investigators at Washington University (St. Louis, MO, USA) recently described using a single-wavelength pulse-width-based PAM method with a one-dimensional imaging rate of 100 kHz to image blood oxygenation with capillary-level resolution in the mouse brain.

They reported in the March 30, 2015, online edition of the journal Nature Methods that this technology enabled them to take images of blood oxygenation 50 times faster than in previous studies using fast-scanning PAM; 100 times faster than an acoustic-resolution system; and more than 500 times faster than phosphorescence-lifetime-based two-photon microscopy (TPM).

“Using this new single-wavelength, pulse-width-based method, PAM is capable of high-speed imaging of the oxygen saturation of hemoglobin,” said senior author Dr. Lihong Wang, professor of biomedical engineering at Washington University. “In addition, we were able to map the mouse brain oxygenation vessel by vessel using this method. PAM is exquisitely sensitive to hemoglobin in the blood and to its color change due to oxygen binding. Without injecting any exogenous contrast agent, PAM allows us to quantify vessel by vessel all of the vital parameters about hemoglobin and to even compute the metabolic rate of oxygen. Given the importance of oxygen metabolism in basic biology and diseases such as diabetes and cancer, PAM is expected to find broad applications.”

Related Links:

Washington University


Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Specimen Collection & Transport
POCT Fluorescent Immunoassay Analyzer
FIA Go
Gold Member
ADAMTS-13 Protease Activity Test
ATS-13 Activity Assay

Print article

Channels

Clinical Chemistry

view channel
Image: Reaching speeds up to 6,000 RPM, this centrifuge forms the basis for a new type of inexpensive, POC biomedical test (Photo courtesy of Duke University)

POC Biomedical Test Spins Water Droplet Using Sound Waves for Cancer Detection

Exosomes, tiny cellular bioparticles carrying a specific set of proteins, lipids, and genetic materials, play a crucial role in cell communication and hold promise for non-invasive diagnostics.... Read more

Molecular Diagnostics

view channel
Image: The study showed the blood-based cancer screening test detects 83% of people with colorectal cancer with specificity of 90% (Photo courtesy of Guardant Health)

Blood Test Shows 83% Accuracy for Detecting Colorectal Cancer

Colorectal cancer is the second biggest cause of cancer deaths among adults in the U.S., with forecasts suggesting 53,010 people might die from it in 2024. While fewer older adults are dying from this... Read more

Hematology

view channel
Image: The Gazelle Hb Variant Test (Photo courtesy of Hemex Health)

First Affordable and Rapid Test for Beta Thalassemia Demonstrates 99% Diagnostic Accuracy

Hemoglobin disorders rank as some of the most prevalent monogenic diseases globally. Among various hemoglobin disorders, beta thalassemia, a hereditary blood disorder, affects about 1.5% of the world's... Read more

Microbiology

view channel
Image: The new platform is designed to perform blood-based diagnoses of nontuberculosis mycobacteria (Photo courtesy of 123RF)

New Blood Test Cuts Diagnosis Time for Nontuberculous Mycobacteria Infections from Months to Hours

Breathing in nontuberculous mycobacteria (NTM) is a common experience for many people. These bacteria are present in water systems, soil, and dust all over the world and usually don't cause any problems.... Read more

Industry

view channel
Image: These new assays are being developed for use on the recently introduced DxI 9000 Immunoassay Analyzer (Photo courtesy of Beckman Coulter)

Beckman Coulter and Fujirebio Expand Partnership on Neurodegenerative Disease Diagnostics

Beckman Coulter Diagnostics (Brea, CA, USA) and Fujirebio Diagnostics (Tokyo, Japan) have expanded their partnership focused on the development, manufacturing and clinical adoption of neurodegenerative... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.