Background: While ultrasound imaging of the thoracic paravertebral space in 2-dimensional (D) mode allows examination of the paravertebral anatomy in the transverse or sagittal axis, volumetric 3D ultrasound imaging provides multiplanar images in several orthogonal (perpendicular) planes and may provide additional anatomical information. In this imaging study we assessed the feasibility of 3D ultrasound imaging of the anatomical area relevant to the thoracic paravertebral block.
Methods: Four healthy young adult volunteers were recruited. With the volunteer in the sitting position, the C7 spinous process and the spinous processes of the T1 to 5 vertebra were identified. All images were obtained using a Philips iU22 ultrasound system with a high-frequency 3D 4D volume linear array transducer (13 to 5 MHz). A 3D volumetric scan of the right thoracic paravertebral region was performed with the sagittal plane as the data acquisition plane.
Results: With 3D multiplanar scanning, the sagittal, transverse, and coronal views of the paravertebral anatomy were simultaneously visualized in all subjects. Unlike 2D images, the articulation between the neck of the rib and the transverse process was well delineated in the sagittal and coronal images of the multiplanar scans. The rendered 3D volume allowed an in-depth view of the paravertebral anatomy from all sides (i.e., top, bottom, front, back, left, and right).
Conclusions: Volumetric 3D ultrasound imaging of the thoracic paravertebral space is feasible and provides more detailed spatial anatomical information than 2D ultrasound imaging.