Photoacoustics to guide and monitor ultrasound therapy

Amaury Prost , Mathieu Pernot (1) , Jean-Marie Chassot , Emmanuel Bossy (2)

1 Physique des ondes pour la médecine
2 IL - Institut Langevin - Ondes et Images (UMR7587)

Photoacoustic imaging has recently been proposed as a promising method to guide and/or monitor therapy based on high intensity focused ultrasound (HIFU). In this work, different steps of a photoacoustic-guided HIFU scenario will be presented. The initial step involves detecting selectively the photoacoustic signals from a targeted area, such as a tumor. To do so, functionalized gold nanoparticules are interesting contrast agents as their absorption spectrum presents a strong resonance, providing a way to discriminate GNR-generated photoacoustic signals from background signals. Once selectively detected, photoacoustic signals may be used to refocus HIFU towards the targeted area, based for instance on time-reversal approaches. As the optical properties of the targeted area change during therapy, photoacoustic imaging may also be used to monitor the therapy process. This work will present results obtained with a special dual-mode 128-element array, designed for both photoacoustic detection and HIFU emission with the same elements. Results on the detection of GNR-loaded cells in vitro and real-time photoacoustic-assisted HIFU will be presented.

Mots clés: Photoacoustics; HIFU; Therapy

Domaines: Acoustique [physics.class-ph]

Amaury Prost, Mathieu Pernot, Jean-Marie Chassot, Emmanuel Bossy. Photoacoustics to guide and monitor ultrasound therapy. Acoustics 2012, Apr 2012, Nantes, France. ⟨hal-00811251⟩