Reliability of peripheral intraneural microhemodynamics evaluation by using contrast-enhanced ultrasonography

The purpose of the study was to validate the reliability of quantitative intraneural enhancement patterns by using contrast-enhanced ultrasonography (CEUS).

Nine asymptomatic wrists underwent a total of three CEUS examinations each conducted at 1-month intervals. The CEUS enhancement pattern of median nerves was quantitatively evaluated. The area under the time-intensity curve was calculated by placing the regions of interest at the proximal, center, and distal regions of the median nerve. An intra-class correlation coefficient for intra-observer, inter-observer, and inter-examination reproducibility was calculated.

The intra- and inter-observer reproducibility was almost perfect. Inter-examination reproducibility of the proximal, center, and distal regions was 0.891, 0.614, and 0.535, respectively. In this study, we found that the reproducibility of the distal and center regions of the median nerve in the carpal tunnel was lower than that of the proximal region.

High intra-observer, inter-observer, and inter-examination reproducibility of CEUS was obtained in the evaluation of the intraneural enhancement pattern when the region of interest was placed in the proximal region of the median nerve.