Finding answers in the blood

DOUGLAS FARMER, SENIOR EDITOR doug.farmer@photonics.com

Blood tests are vital in the diagnosis of many conditions, especially where anemia and other blood disorders are common — for example, in developing countries and areas such as sub-Saharan Africa, where a team of researchers recently tried an optical approach to blood hemoglobin assessment. After blood is drawn from a patient in a hospital setting, it is usually examined using expensive, bulky equipment. And in some cases, blood draws are performed on patients who are in a weakened state, or who already have a reduced hemoglobin level in the blood. Researchers at Purdue University sought a better way.

Sang Mok Park and Young Kim, the co-authors of this month’s cover story, researched a smartphone-based spectroscopic technique to measure levels of blood hemoglobin. The device, driven by superresolution imaging, can be calibrated to an individual’s diagnostic characteristics and used to noninvasively image the inner eyelid. A variety of spectral measurements can be made from the images obtained with this technique.

A team tested the app-based device in a clinical study in Kenya, collaborating with agencies working on the ground. The Purdue researchers’ innovative approach won first prize in the National Institutes of Health Technology Accelerator Challenge, which awarded the team $400,000 to scale up the development of their technology on the front lines of medical care. Read more here.

To share research and discovery in optical technologies during these times of reduced travel, our sister magazine sponsored the first virtual Photonics Spectra Conference on Jan 19-22. The Biomedical Imaging track of the event is available online at PhotonicsSpectraConference.com. Viewers of the on-demand material will hear from top researchers, such as Aydogan Ozcan of UCLA, who, in his keynote session, discusses how deep learning can advance optical microscopy; Jürgen Popp of the Leibniz Institute, who covers biophotonics in point-of-care settings; and Adam Wax of Duke University, who discusses the 3D printing of OCT system parts.

Those interested in photoacoustic imaging will appreciate the feature by Eno Hysi, Darren A. Yuen, and Michael C. Kolios, who discuss the ways that the modality can be used for studying the buildup of fibrosis in donated kidneys. They write about how two dominant chromophores that represent blood and collagen provide the required information. Learn about the work here.

Richard Yang outlines the considerations that must be weighed when designing an endoscope that can inform a surgeon in real time during a procedure. Image resolution, field of view, focal length, and device size must all be prioritized in diagnosis and treatment. He covers the possibilities here.

Switching the focus to the components that make imaging systems effective, authors Regina Gumenyuk, Pablo Loza-Alvarez, and Simone Morselli reveal how, by using novel laser sources that are driving imaging technologies, they are able to explore segments of the spectrum that help to identify the presence of cancer where the disease has historically gone mostly undetected. Read about their important work here.

Enjoy the issue!