The feasibility of noninvasive image-guided treatments of brain disorders by focused ultrasound

Abstract

Brain disorders, such as tumors, functional problems, etc., are difficult to treat and the invasive interventions often disturb surrounding brain tissue, resulting in complications. In addition, the delivery of therapeutic agents to the brain via the blood supply is often impossible because the blood brain barrier protects the brain tissue from foreign molecules. Our hypothesis has been that transcranial therapeutic ultrasound exposures can be delivered with an optimized phased-array system. We have demonstrated that highly focused therapeutic ultrasound beams can be accurately delivered through an intact human skull noninvasively. Furthermore, we demonstrated using ex vivo human skulls that we can use CT-derived information to predict the phase shifts required for correcting the wave distortion. We have also developed a method to focally disrupt the blood brain barrier without damaging the neurons in the targeted tissue volume. This may allow delivery of therapeutic or diagnostic agents into image-specified locations. Successful transcranial delivery of ultrasound in a clinical setting may have a major impact on the treatment of brain disorders in the future.