Dr. Tali Ilovitsh
Ultrasound is a widely used medical imaging and therapeutic modality, due to its safety, noninvasiveness, penetration depth and cost effectiveness compared to other modalities. However, limitations in resolution, contrast and acquisition time restricts the resulting performance. In the first part of my talk I will present two methods that were developed to address these challenges by manipulating the emitted acoustical field in order to increase the depth of field or reduce the side lobes for enhanced image contrast.
The second part of my talk will focus on therapeutic ultrasound using microbubble contrast agents. Lipid-shelled, gas-filled microbubbles are widely used in ultrasound imaging and therapy. Upon ultrasound excitation, microbubbles expand and contract, enhancing the permeability of the surrounding tissue. In recent years, a game changing ultrasound technology has emerged, enabling noninvasive treatment of the brain at low frequencies that are capable of penetrating through an intact human skull. Our results indicate that at 250 kHz, well below the resonance frequency of these agents, the vibrational response of microbubbles is enhanced. Our work was aimed to safely and transiently open the blood brain barrier via transcranial ultrasound in mice. Based on these findings, we recently developed a flexible therapeutic platform that uses low frequency ultrasound combined with an intratumoral injection of cell-targeted microbubbles to enhance breast-tumor transfection, while reducing tumor viability, debulking tumor mass and enhancing immune and T-cell infiltration.