Improving real-time ultrasound spine imaging with a large-aperture array

Ultrasound offers a safe, low-cost alternative to computed tomography (CT)
and magnetic resonance imaging (MRI) for spinal diagnostics and
intervention by enabling real-time imaging. However, the complex structure
of the spine and acoustic shadowing from bones present challenges for
ultrasonography. This study addresses these limitations using an 8.8-cm
384-element large-aperture array and full aperture-based imaging
protocols. Volumetric scanning across multiple vertebrae was accomplished
in 5 seconds using ultrafast, diverging wave acquisition. In 7 healthy
volunteers, the large-aperture array and diverging wave transmission
improved resolution, contrast, and visualization of the spinal canal,
venous plexuses, and facet joints compared with conventional probes. A
comparison between the co-registered CT and ultrasound scan confirmed the
imaging accuracy. A simulated lumbar puncture demonstrated needle tip
visualization throughout the trajectory into the spinal canal. The results
suggest that large-aperture arrays, coupled with plane or diverging
protocols, are a valuable tool for spine imaging and image-guided
intervention.