Effect of skin–capsular distance on controlled attenuation parameter for diagnosing liver steatosis in patients with nonalcoholic fatty liver disease
Abstract Background The effect of the skin–capsular distance (SCD) on the controlled attenuation parameter (CAP) for diagnosis of liver steatosis in patients with nonalcoholic fatty liver disease (NAFLD) remains unclear. Methods The SCD was measured using B-mode ultrasound, and the CAP was measured using the M probe of FibroScan®. According to the indications of the M probe, 113 patients with an SCD of ≤ 25 mm were included in the present study. The association between the SCD and CAP was investigated, and the diagnostic performance of the SCD-adjusted CAP was tested. Results The SCD showed the most significant positive correlation with the CAP (ρ = 0.329, p < 0.001). In the multiple regression analysis, the SCD was associated with the CAP independent of pathological liver steatosis. The adjusted CAP was calculated as follows: adjusted CAP (dB/m) = CAP − (5.26 × SCD). The area under the receiver operating characteristic curve for diagnosis of a steatosis score ≥ 2 was significantly greater for the adjusted CAP than original CAP. Conclusions The SCD is associated with the CAP independent of liver steatosis. Adjustment of the CAP using the SCD improves the diagnostic performance of the CAP in NAFLD.