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Updated: Aug 6, 2026

A Patient-Derived Xenograft Model for Venous Malformation
Published on: June 15, 2020
Incidence and diagnostic yield of repeat imaging-based screening for hepatic arteriovenous malformations in patients
Benjamin Cho1, Leena Usman1, Torianna Lomax Truong2,3
1Division of Gastroenterology and Hepatology, Department of Medicine, University of California-San Francisco, San Francisco, California, USA.
Background And Aims:
Hepatic arteriovenous malformations (HAVMs) are a common visceral manifestation of hereditary hemorrhagic telangiectasia that can lead to heart failure and biliary ischemia. Current guidelines recommend baseline hepatic screening in adulthood, but the utility of repeat imaging after an initial negative or nonactionable finding remains unclear. We sought to clarify the prevalence of clinically significant HAVMs following negative or nonactionable imaging.
Approach And Results:
We isolated all adult patients with hereditary hemorrhagic telangiectasia evaluated at the University of California, San Francisco HHT Center of Excellence between 2013 and 2025. HAVM status was determined by natural language processing of unstructured clinical and radiology notes. Of 477 patients, 195 (40.9%) had initial imaging interpreted as either HAVM-negative or nonactionable, defined as HAVM-positive but not clinically significant to warrant further imaging. Of the 195, 30 (15.4%) underwent repeat hepatic imaging. Of the 30, 17 (56.7%) were screened incidentally and 13 (43.3%) were screened due to new signs and/or symptoms. Clinically significant HAVMs were identified in 2 patients, representing a 1.0% frequency of subsequent detection among all patients who were HAVM-negative/nonactionable and 6.7% among those re-imaged. Across 48 total repeat imaging studies, the detection rate per study was 4.2%. Across 386.5 person-years of follow-up, the incidence rate of clinically significant HAVM recognition was 0.52 per 100 person-years.
Conclusions:
Both instances of HAVM identification reflected evolving clinical features and reinterpretation of prior imaging, not de novo lesion development. These findings support periodic reassessment of initial negative/nonactionable screening studies, with a low threshold for reassessment in the presence of new signs and symptoms.
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