Needle-free Blood Test Gives Painless Diagnosis

Blood scanning system could cut traditional blood draws

/ Author:  / Reviewed by: Chris Galloway, M.D.

(RxWiki News) Do you find the needle prick associated with a traditional blood test painful or even frightening? Then you'll appreciate the latest technology in examining blood sans the needle.

Scientists have developed a real-time method that provides as much information as a traditional blood test, but it requires only a light that is shined through the skin.

"Receive regular blood tests to identify medical conditions early."

Lior Golan, a graduate student in the Department of Biomedical Engineering at the Israel Institute of Technology, described the newly developed device as a portable optical microscope about the size of a breadbox that is capable of viewing blood cells as they flow inside the body.

The microscope could immediately identify potentially severe medical problems such as a high white blood cell count. It also could easily be used to screen large populations for common blood disorders.

The device uses spectrally encoded confocal microscopy to create images by splitting a light beam into a line of constituent colors from red to violet.

Researchers tested the device by imaging blood flowing through a vessel in the lower lip of a volunteer. The lower lip was selected because it is rich in blood vessels, does not contain pigment that can block light and would not lose blood flow, even in trauma patients.

A probe was pressed against the skin and a rainbow-appearing line of light was directed across the blood vessel near the skin's surface. When blood cells crossed the line, information-containing light was scattered, which scientists collected and analyzed.

A computer program interpreted the findings and created two-dimensional images of the blood cells.

During the test, researchers measured the average diameter of red and white blood cells and calculated the percent volume of various cell types, which can be key to diagnosing different medical conditions. The test can quickly image a large number of cells.

Other blood scanning devices have been developed, but most have been bulky or required injecting potentially dangerous fluorescent dye prior to the test.

Investigators are currently working to develop a similar device with a higher penetration depth, which could allow for a range of other imaging sites in addition to the lower lip. They plan to develop a thumb-size version of the already-developed device within the next year.

The research was recently published in the Optical Society's journal Biomedical Optics Express.

Reviewed by: 
Review Date: 
May 24, 2012
Last Updated:
August 10, 2012