Z Gastroenterol 2011; 49 - P5_06
DOI: 10.1055/s-0030-1269712

Liver stiffness in obese patients: First experience using the novel XL probe for vibration-controlled transient elastography

E Durango 1, G Millonig 1, HK Seitz 1, S Mueller 2
  • 1Zentrum für Alkoholforschung, Lebererkrankungen und Ernährung, Krankenhaus Salem und Universität Heidelberg, Heidelberg, Heidelberg
  • 2Zentrum für Alkoholforschung, Lebererkrankungen und Ernährung, Krankenhaus Salem und Universität Heidelberg, Heidelberg, Heidelberg

Aims: Measurement of liver stiffness (LS) by vibration-controlled transient elastography [VCTE/Fibroscan] is limited in patients with obesity and ascites. We here test and compare the recently developed more powerful XL probe versus the conventional M probe.

Methods: LS was measured in 129 obese and non-obese patients (BMI range 17.2–72.4) using both the M and XL probe. In addition, BMI, waist to hip ratio, transaminases and liver ultrasound parameters were obtained.

Results: LS was not measurable in 6 patients (4.6%) by the XL probe as compared to 32 patients (24.8%) by the M probe. Almost halve of the patients not measurable with the M probe showed fibrotic stiffness values with the XL probe. Notably, even patients with ascites up to 31mm distance were measurable with the XL probe. ROC analysis indicates that skin-liver capsula distance, hip circumference and BMI are the best clinical parameters whether LS can be measured or not. Out of the 6 patients not measurable with the XL probe, four had a BMI>30 but two were non obese. Even 10 non obese patients were not measurable with the M probe. LS measurement failure in non obese patients especially with the M probe was in two cases due to ascites but mainly to a specific type of subcutaneous fat tissue with poor ultrasound propagation. LS by M and XL probe were highly correlated (r=0.98, P<0.01). The mean difference between LS measured with M-probe compared to XL-probe was ca. 10%. Only in three patients, this difference was higher than 100% without affecting the fibrosis group allocation. Generelly, XL-probe obtained LS tends to be slightly lower as compared to the M probe.

Discussion and conclusion: The novel more powerful XL probe drastically improves the success rate of LS measurements in patients with obesity and ascites. Patients with a BMI above 40 and lean patients with a specific type of subcutaneous fat tissue with poor ultrasound penetration are still problematic despite the use of the XL-probe.

FibroScan - Liver stiffness - ascites - obesity - transient elastography