Blood-Brain Barrier Gets Drugs With The Help Of Focused Ultrasound And Microbubbles
In order to prevent infections and contamination within the brain, one of the most important defense mechanism if named would be the blood- brain barrier. However, the very same defense mechanism ends up causing great difficulty to let therapeutic drugs such as chemo agents pass into the brain. In order to address this challenge that doctors have been facing for so long, an innovative method for pushing drugs across the blood- brain barrier has been developed by the researchers at Washington University in St. Louis.
Cavitation dose painting, the technique involved here, depends on focused ultrasound to push microbubbles along with the drug molecules across the blood- brain barrier without causing any harm as such. Being a contrast agent to ultrasound, microbubbles happen to be excessively sensitive to the waves of ultrasound. A localized pumping action is created once microbubbles puff up and back down as ultrasound waves pass through them. In the same direction where the ultrasound waves are headed, this motion can end up creating a push. Consequently, making it possible to target the drug to enter the brain in that area where the drug is required to reach.
The researchers were able to see how much drug ends up actually being transported across the blood brain barrier, by combining cavitation dose painting with passive cavitation imaging, a technique that can visualize the concentration of microbubbles.
For proper conformation of the results obtained, a comparison of the results with positron emission tomography (PET) imaging was attempted by the team. A ldquo;pixel by pixelrdquo; correlation between PET and ultrasound imaging in terms of tracking drug particles was observed.