Sonolucent Burr Hole and Implantable Acoustic Lens Permitting and Enhancing Transcranial Ultrasound

Unmet Need: Brain imaging techniques are commonly used to visualize the distribution of tissues and fluids within the skull. These techniques are classically used to either (1) diagnose abnormalities in the structure of the brain (traumatic brain injury, stroke, tumors, abnormal fluid buildup, etc.) or (2) provide a real-time visual aid for surgeons and physicians providing neurosurgical care. Ultrasound is one of the most accurate and cost-effective transcranial imaging methods, with alternatives like CT scans or MRIs sometimes costing more than two-to-four times as much, depending on the healthcare service provider. Nevertheless, ultrasound is not a viable option for imaging the brain for most adults because the technique cannot penetrate the skull. As a result, CT scans are typically used for brain imaging of adults, with ultrasound techniques limited for use during neurosurgery. In addition, the burr hole cover has a small footprint (ie. just 14 millimeters wide) which limits the viewpoint from a handheld transducer, and thus, an additional “lens” effect built within easily helps to overcome this obstacle. As such, there is a need for methods that enable non-invasive brain imaging of adults by ultrasound and implant lens, thereby, lower of the cost of care for patients with suspected or existing brain injuries.

Technology Overview: The reported invention consists of a small, translucent window made of biomaterials that allows ultrasound to pass into the skull and is installed into the skull following surgeries that generate a burr hole and has an optical lens built within, analogous to commonly-worn bifocal glasses. Burr holes are standard components of most neurological, ears/nose/throat, orthopedic, maxillofacial, plastic, and some ocular surgeries. The invention enables and enhances the non-invasive use of ultrasound brain imaging in post-operative adult patients, thereby allowing physicians to more cost-effectively make diagnostic and therapeutic determinations for patients.

Stage of Development: The inventors have performed proof-of-principal studies, whereby they installed the invention into the skull of human cadavers, successfully imaged their brains five days after the operation, and identified structural characteristics that are consistent with CT scans taken of the same subjects.

Publication: Belzberg, et. al. Journal of Craniofacial Surgery 30, 1456-1461, 2019