title: Factors influencing reliability of liver stiffness measurements using transient elastography (M-probe)-monocentric experience.
abstract: OBJECTIVE
  To retrospectively assess the feasibility of transient elastography (TE) and the factors associated with failed and unreliable liver stiffness measurements (LSMs), in patients with chronic liver diseases.
  
  
  METHODS
  Our retrospective study included 8218 consecutive adult patients with suspected chronic liver diseases. In each patient, LSMs were performed with a FibroScan(®) device (Echosens, France), with the M probe. Failure of TE measurements was defined if no valid measurement was obtained after at least 10 shots and unreliable if fewer than 10 valid shots were obtained, success rate (SR) <60% and/or interquartile range interval/median value (IQR/Med) ≥30%.
  
  
  RESULTS
  From the 8218 patients, failed and unreliable LSMs were observed in 29.2% of cases. In univariant analysis, the following risk factors were associated with failed and unreliable measurements: age over 50 years (OR 2.04; 95%CI 1.84-2.26), female gender (OR 1.32; 95%CI 1.20-1.45), BMI>27.7kg/m(2) (OR 2.89, 95%CI 2.62-3.19), weight>77kg (OR 2.17; 95%CI 1.97-2.40) and height<162cm (OR 1.26; 95%CI 1.14-1.40). In multivariate analysis all the factors mentioned above were independently associated with the risk of failed and unreliable measurements. If all the negative predictive factors were present (woman, older than 50 years, with BMI>27.7kg/m(2), heavier than 77kg and shorter than 162cm), the rate of failed and unreliable measurements was 58.5%. In obese patients (BMI≥30kg/m(2)), the rate of failed and unreliable measurements was 49.5%.
  
  
  CONCLUSIONS
  Failed and unreliable LSMs were observed in 29.1% of patients. Female gender, older age, higher BMI, higher weight and smaller height were significantly associated with failed and unreliable LSMs.
authors.affiliation: Department of Gastroenterology and Hepatology, "Victor Babes" University of Medicine and Pharmacy Timişoara, Romania. roxanasirli@gmail.com
authors.forename: Roxana
authors.initials: R
authors.lastname: Sirli
authors.forename: Ioan
authors.initials: I
authors.lastname: Sporea
authors.forename: Simona
authors.initials: S
authors.lastname: Bota
authors.forename: Ana
authors.initials: A
authors.lastname: Jurchiş
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000706:statistics & numerical data*; D058625:End Stage Liver Disease / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology*; D015588:Observer Variation; D015995:Prevalence; D015203:Reproducibility of Results; D012307:Risk Factors; D012383:Romania / Q000453:epidemiology; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D055815:Young Adult