Sonographic imaging of the stellate ganglion in healthy adults: An observational study.

The aim of this study is to estimate the normal cross-sectional area and diameter of the stellate ganglion (SG) by ultrasound (US) in healthy adults. The study sample included 80 stellate ganglia in 40 participants (15 males, 25 females), mean age 38 years, mean height 162.5 cm, mean weight 67.8 kg, mean body mass index 25.4 kg/m2. Two radiologists separately obtained US images of the bilateral SG. Each participant was scanned 3 times bilaterally to assess for intra-observer reliability. The mean diameter of the SG was 1 mm (range: 0.1-2). The mean CSA of the bilateral SG was 1.3 mm2 (range: 0.6-3.9). The SG diameter positively correlated with age. Our study demonstrates the ability of US to image the SG and estimate its normal diameter and CSA. Knowledge of how to identify and measure the SG during ultrasound-guided procedures would be expected to decrease the risk of associated complications and help establish normal reference values.