Background and Aim: Liver stiffness measurement (LSM) using transient elastography (TE) evaluates liver fibrosis.In some cases, reliable stiffness measurements by standard M probe are not obtained, especially in overweight (BMI≥25kg/m2) and obese (BMI≥30kg/m2) patients so that the XL probe was developed. The aim of our paper was to assess the usefulness of the XL probe in daily clinical
practice.
Material and Method: Our study included 216 patients with chronic HBV, HCV hepatitis or with NASH, in which paired measurements were
made with the M (3.5MHz) and XL (2.5 MHz) probes. In each patient 10 valid LSM were acquired with each probe, the median value
was calculated expressed in kiloPascals (kPa). Unreliable LSM were considered the following: fewer than 10 valid shots; with a success rate (SR)<60% and/or interquartile range interval (IQR)≥30%. Paired t test was used to compare LSMs obtained with both
probes.
Results: In 127 patients reliable LSM could not be obtained by M probe, 10 in normal weight (BMI<25kg/m2), 25 in overweight, and 92 in obese. By XL probe reliable measurements were obtained in 80/127 (63%) of those: 8/10 (80%) in normal weights; 17/25 (68%) in
overweights; and 55/92 (59.8%) in obese. In 89 patients with reliable M probe measurements, XL probe LSMs were also performed. LS values obtained by XL probe strongly and significantly correlated with those obtained by M probe (Spearman r=0.789, p<0.0001). The mean LS values by XL probe were significantly lower than those obtained by M probe [median 7.7 kPa (range 3.7 –
69.1) vs. 6.4 kPa (range 3.1 – 53.8), Wilcoxonpaired t test p<0.001)
Conclusion: By using the XL probe, reliable LSM can be obtained in more than 60% of patients with unreliable measurements by M probe. LSM by XL probe are significantly correlated, but lower, than those obtained by M probe.
Acknowledgements: Isabel Dan, Nadia Cornu, Melania Ardelean
