Leaky-wave focused Ultrasound through Metamaterial ENgineering (LUMEN)

forthcoming

Transcranial focused ultrasound (tFUS) is a promising non-invasive technology capable of targeting specific brain regions to treat, among others, movement disorders such as essential tremor and Parkinson’s disease tremor. Yet, its effectiveness is currently limited by the excitation of leaky Lamb waves, which radiate energy at arbitrary angles in the brain, causing undesired aberrations. To mitigate these effects, the state-of-the-art technology for tFUS relies on patient-tailored aberration compensation strategies that take advantage of more invasive techniques, such as MRI guidance and X-Rays, making tFUS not accessible for all patients, expensive, and not readily available for small-scale laboratories. LUMEN addresses these challenges by dressing the patient with acoustic metasurfaces, engineered structures designed to manipulate wave propagation. Instead of compensating for aberrations a posteriori, this project leverages acoustic metasurfaces to control the leaky-wave radiation mechanism at the source, creating functional devices able to focus ultrasound without the need for more invasive and complex correction strategies, thereby revolutionizing the focusing mechanism of tFUS. This approach not only aims to make tFUS more affordable, but also enhances the ability of tFUS to reach peripherical regions of the brain that are typically hard to access and provides a focusing mechanism effective across diverse skull geometries, making it suitable to treat different patients. The outcomes of this research have the potential to transform the treatment landscape for millions suffering from tremor disorders, neuropathic pain, cancer-related pain, while also advancing the fields of wave physics, medical imaging, and therapeutic technology. Achieving these goals could lead to more inclusive, non-invasive therapeutic options, greatly improving patients' quality of life and reducing healthcare costs globally.