Interobserver agreement in diagnosing liver involvement in hereditary hemorrhagic telangiectasia by Doppler ultrasound
The purpose was to evaluate interobserver agreement on Doppler ultrasonographic (US) diagnosis of liver vascular malformations (VMs) in hereditary hemorrhagic teleangiectasia (HHT) and on their severity grading. During the interobserver agreement study, three observers with at least seven years of specific experience using Doppler US for the diagnosis of liver VMs, judged about the presence/absence of liver VMs and their severity on a set of images and videoclips. Interobserver agreement was estimated with kappa statistics. One-hundred ten cases were reviewed during interobserver study (80 cases with liver VMs, 30 without). Very good kappa values of the interobserver agreement were found for all pairs concerning the distinction between presence and absence of hepatic VMs. All observers demonstrated excellent sensitivity and specificity in identifying hepatic VMs, with their respective areas under the curve ranging from 0.97 to 0.99. Interobserver agreement among the three investigators in staging the hepatic VMs in HHT patients was moderate (Kendall's coefficient of concordance = 0.26). Study results indicate that Doppler US diagnosis of liver VMs in HHT has a high degree of agreement among ultrasonographers; a moderate agreement was found regarding severity staging.