Ultrasonographic analysis of HAVMS in a large cohort of hereditary hemorrhagic telangiectasia patients: definition of a new highly-accurate intrahepatic parameter

Background: Hereditary hemorrhagic telangiectasia (HHT) is a rare genetic disorder (1:5000) whose diagnosis is based on 3/4 of the following criteria: familiar history, epistaxis, mucocutaneous telangiectases, visceral arteriovenous malformations. Hepatic arteriovenous malformations (HAVMs) have been found in more than 70% HHT patients by multislice CT (MSCT). Due to its noninvasivity and low cost, echo-color Doppler has recently been considered a valuable tool for long-term of HHT-related HAVMs; however, only open studies of selected patient cohorts using mainly extrahepatic ultrasonographic criteria are currently available. Aim of Study: To perform a blind controlled study with echo-color Doppler as a screening procedure for HAVMs in a large cohort of unselected HHT patients for investigation of the accuracy of “color spots” (a new intrahepatic echo-color Doppler parameter) and to compare its accuracy together with that of previously-reported extrahepatic ultrasound criteria (1) for diagnosis of HAVMs. Methods: 153 HHT patients (80 males and 73 females, mean age 47±15, range 15-75 yrs) were systematically screened with abdominal MSCT (considered as the gold standard) and echo-color Doppler (HDI-9ATL System) by two independent operators to evaluate the presence of HAVMs. Both intrahepatic parameters (“color spots” with high velocity and low resistance index) and extrahepatic parameters (diameter, flow velocity and tortuosity of hepatic artery and portal vein) were utilized. The sensitivity and specificity for both classes of criteria were assessed (Cramer’s V-index). Results: MSCT was positive in 128/153 (84%) HHT patients. Doppler color spots were found in 130/153 patients (see Table). The sensitivity, specificity and diagnostic accuracy of color spots compared to MSCT were 95%, 68% and 91%, respectively, and the 'color spot criterion' showed a greater correlation to MSCT (V-index = 0.655; p<0.0001) than the extrahepatic criteria (V = 0.39) (1). Conclusions: A new echo-color Doppler intrahepatic parameter (“color spot”) was identified showing an optimal accuracy for detecting HAVMs in HHT, thus permitting a non-invasive, ideal strategy for periodical screening of HHT patients. These data support the superiority of intrahepatic compared to extrahepatic criteria for identification of HAVMs.