Liver stiffness measurements by means of Supersonic Shear IMAGING (SSI) should be performed in fasting condition or not?

Purpose: To assess the influence of food intake on liver stiffness (LS) measurements by means of SSI, knowing that food intake increase LS values assessed by means of other two elastographic methods (Transient Elastography and Acoustic Radiation Force Impulse elastography).

Patients and methods: Our study included 75 healthy volunteers, with a median age of 25 years (19 – 58 years), 58 women (77.3%) and 17 male (22.7%). SSI measurements were performed in fasting condition, then 1h and 3h after a standard meal. All subjects included in the study received the same meal: one sandwich and 500 ml water. SSI measurements were performed in supine position. In each patient 5 valid SSI measurements were performed by intercostals approach, a median value was calculated and expressed in kilopascals (kPa).

Results: In 3 patients we could not obtain 5 valid LS measurements assessed by means of SSI in at least one condition (fasting, 1h and 3h after food intake), so in the final analysis were included 72 subjects (96% of all healthy volunteers). The mean LS values were similar in fasting condition, 1h and 3h after food intake were: 6.1 ± 1.3 kPa, 5.8 ± 1.1 kPa and 5.7 ± 1.1 kPa, respectively. No significant differences were observed between mean SSI values in the different food conditions: fasting vs. 1h after food intake: p = 0.28, fasting vs. 3h after food intake: p = 0.17 and 1h. vs. 3h after food intake: p = 0.80 respectively.

Conclusions: LS values assessed by means of SSI had similar values in fasting condition and after food intake, so probably food condition is not an issue for SSI measurements, but further studies are still necessary.