Where no sound wave has gone before: first high-resolution transcranial images of the brain using ultrasound computed tomography.

BACKGROUND: Point-of-care imaging of the brain is a major unmet need. Attenuation of ultrasound by the skull hinders sonographic evaluation of the brain in adults. PURPOSE: Ultrasound tomography holds potential in sonographic imaging of the brain through the skull. This work assesses the ability of a commercial ultrasound tomography machine to image the human brain. MATERIALS AND METHODS: A cadaveric specimen was prospectively imaged in the SoftVue commercial ultrasound tomography machine from August to September 2025. A neurosurgeon placed a 40-cc water-filled inclusion in the left cerebral hemisphere intended to mimic hemorrhage. Ultrasound tomography was obtained before and after the inclusion placement without and with an intervening cadaver skull. Fellowship trained neuroradiologists assessed the images for quality and visualization of key anatomic structures and inclusions. Sound speed values, signal-to-noise ratios, and contrast-to-noise ratios were also calculated on the acquired images. RESULTS: Ultrasound tomography allowed visualization of basic brain anatomy without a skull. The spatial resolution of the images without the skull was approximately 0.75 mm. Additionally, the implanted water-filled inclusion mimicking hemorrhage was visualized through the skull per neuroradiologist assessment. The implanted inclusion could also be quantitatively identified as different from the surrounding normal anatomy. CONCLUSION: Ultrasound tomography allowed visualization of major brain anatomy and a water-filled inclusion mimicking hemorrhage in the brain parenchyma demonstrating potential utility in neuroimaging. Ultrasound tomographic images through the skull visualizing the water-filled inclusion mimicking hemorrhage were also obtained showing the potential value of ultrasound tomography in intact samples.