A new human brain imaging technology employs laser light and ultrasonic sound waves. Improvements to photoacoustic computerized tomography (PACT) technology are part of the advancement. It is so precise and sensitive that the researchers could identify even minute variations in the amount of blood moving through tiny blood arteries and the oxygenation status of that blood. Blood flow increases to specific brain areas during cognitive tasks. So, a human brain imaging device that shows blood concentration and oxygenation changes can help researchers and medical professionals monitor brain activity.
The technology is considerably simplified, less expensive, and compact. It does not require the patient to enter the machine. A pulse of laser light is beamed into the head to make the human brain imaging method work. The light passes through the patient’s scalp and skull, scattering across the brain, and gets absorbed by oxygen-carrying hemoglobin molecules in the red blood cells.
The hemoglobin molecules vibrate ultrasonically. The vibrations travel back through the tissue. An array of 1,024 tiny ultrasonic sensors positioned around the outside of the head picks them up. A computer algorithm then assembles the blood flow and oxygenation data throughout the brain from those sensors into a 3-D human brain imaging map.