Feasibility study of real-time three-/four-dimensional ultrasound for epidural catheter insertion

The study demonstrates that 4D ultrasound can be used for real-time epidural catheter insertion and has both advantages and limitations compared with the 2D technique. Four-dimensional ultrasound has the potential to improve operator orientation on the vertebral column. However, this comes at the price of decreased resolution, frame rate, and needle visibility. Prospective evaluation of the importance of an acoustic window in neuraxial anaesthesia is required.