A preliminary study on methods and influencing factors of liver zone speed index in healthy subjects / 中华超声影像学杂志

ABSTRACT

Objective To establish the measuring methods and relevant influencing factors of liver zone speed index (ZSI) by sound velocity tissue quantification (SVQ) technology in healthy subjects.Methods Liver ZSI were obtained in 49 healthy volunteers using SVQ technique with Zonare Z.one Ultra system.In the first 15 subjects,ZSI were acquired at four positions (superficial and deep parts of right lobe,superficial and deep parts of left lobe).Then the achievement rate in different position of liver was calculated to select the suitable measuring position.The reproducibility was analyzed with intra-group correlation coefficient(ICC).The last 34 healthy subjects received ZSI measurements in the appropriate position only.The reference value of ZSI was calculated using x-± 1.96 s.Results It was stable to measure values of ZSI with SVQ technique.The achievement rate was higher in right lobe with being 1 cm below the liver capsule for the optimal measuring point.There was no significant difference of ZSI value between male and female groups.There was no significant correlation between age and values of ZSI while a significant negative correlation was found between body mass index (BMI) and values of ZSI (r =-0.63,P =0.000).The reference value of body mass index between 18.5-23.9 kg/m2 was 5.67-36.29 m/s.Conclusions ZSI values of liver measured with SVQ technique shows a good stability and may be a new promising method for assessment of liver elasticity quantitatively.