Cranial self-registration for closed-loop focused ultrasound delivery via a head-worn wearable

Low intensity focused ultrasound (LIFU) is a unique non-invasive neuromodulation approach that enables focal deep brain targeting without also interacting with the overlying neural tissue. To accurately steer the ultrasound beam to these deeper structures in a personalized manner, MRI scans are required of each LIFU user. To meet the level of focal accuracy and precision needed, existing LIFU devices require a provider or clinician to guide their placement in real-time, precluding the application of those systems for repeated use cases at-home for nightly sleep enhancement. To overcome this limitation, Attune Neurosciences developed a first-in-class offline MRI guided, head-worn device (ATTN201) that can deliver LIFU stimulation in any setting. We designed and integrated low profile bilateral ultrasound transducers to interface with the “temporal window”, a thin portion of skull bone posterior to the eyes that allows access to centralized deep brain structures. Custom padding and a detachable fit tool allow the ATTN201 to maintain consistent, repeated positioning of the transducers across sessions. While our approach and beam steering calculations are accurate with consistent device positioning, it is likely that sleeping with the device will cause shifts from the intended position, particularly when encountering external structures like a pillow or the user’s arm. Maintaining accurate beam targeting throughout the night is paramount to closed-loop applications and currently there is no way to correct for nighttime device migration. Furthermore, the careful placement of the device using a registration tool is a burdensome part of the user experience that could be alleviated if the transducers could continuously register their location to the underlying anatomy.We propose to augment our LIFU stimulation device by developing, implementing, and validating an approach for automatically updating and registering the device’s location on the users head. This approach will allow for transducer positional mapping to the individuals underlying cranial morphology, and iterative revision of the beam steering protocols based on their location relative to the 3D location of the brain region of interest. Collectively, this will allow for accurate brain targeting irrespective of ATTN201 device placement or movement on the wearers head, particularly at night during sleep leading to more a more effective and user accessible product.