Negative Correlation between Right and Left Internal Jugular Vein Lateral Diameter Sizes Measured by Ultrasound

We retrospectively examined the relationship of right and left internal jugular vein (IJV) lateral diameters in 190 patients who underwent cardiovascular surgeries. The lateral diameters of bilateral IJVs were measured after induction of anesthesia. The following relationships between the left IJV lateral diameter (L) and the right IJV lateral diameter (R) were investigated: 1) statistical difference of the mean value of R and L, 2) correlation of R and ratio of L to R (L/R ratio), and 3) correlation of L and ratio of R to L (R/L ratio). The results found that the mean value of the right IJV (17.0 ± 4.1 mm) was significantly higher than that of the left (14.4 ± 4.1 mm). There were significant negative correlations between the R and L/R ratio, and between the L and R/L ratio. The results showed dominance of the right IJV in terms of size as has been previously reported. Our finding of a negative correlation between right and left IJV lateral diameter sizes indicates that we can expect a larger size of the contralateral IJV when one side is small. Our present study also indicates the importance of measuring bilateral IJV prior to IJV puncture.