High-definition ultrasound imaging defines the paraneural sheath and fascial compartments surrounding the cords of the brachial plexus at the costoclavicular space and lateral infraclavicular fossa

Background and objectives The paraneural sheath is a multilayered network of collagen fibers that surround the brachial plexus. Currently, there are no sonographic data on plexus, which this study aimed to evaluate. Methods Ultrasound imaging datasets 100 patients who received costoclavicular plexus block, using high-definition ultrasound imaging, were retrospectively reviewed. Video files, representing sonograms before after local anesthetic injection, from space lateral infraclavicular fossa collated reviewed by three experienced anesthesiologists. Frequency (yes/no) visualization sheath, septum, anterior posterior compartments was assessed. Representative visually correlated with archived cadaver microanatomic sections same location. Results Datasets 98 achieved surgical anesthesia evaluated. visualized in 17.3%, 7.1%, 5.1% 5.1%, respectively, at block; contrasts (p<0.001) their visibility post-block (94.9%, 75.5%, 75.5% respectively). At fossa, corresponding these structures 67.7%, 81.5%, 81.5% respectively. images septum well sections. Conclusion We have demonstrated fascial surrounding cords imaging. Trial registration number ClinicalTrials.gov Registry ( NCT04370184 ), https://www.clinicaltrials.gov/ ).