Spectrum of biliary abnormalities in hepatic hereditary hemorrhagic telangiectasia: demonstration by multidetector computed tomography

Hereditary hemorrhagic telangiectasia: how to efficiently detect hepatic abnormalities using ultrasonography

INTRODUCTION

Hereditary hemorrhagic telangiectasia (HHT) is a multiorgan genetic angiodysplastic affection characterized by visceral vascular malformations. It affects mainly the brains, lungs, gastrointestinal tract, and nasal mucosa. Unlike those organs, hepatic involvement, although very frequently occurring, is insufficiently recognized, mainly because of the complex vascular structure of this organ. Thus, treating HHT patients requires a solid understanding of these hepatic anomalies. It is especially important for any general clinicians to be able to recognize clinical findings in HHT, which leads to a high suspicion of HHT and have an index of suspicion for liver abnormalities of HHT. For this purpose, keen awareness of clinical as well as hepatic sonographic (US) findings is paramount.

AIM

The aim of this review is to summarize previously reported findings on the hepatic US through a thorough analysis of related articles, and to (a) determine the role of US in the diagnosis of hepatic involvement in HHT patients and (b) propose the most simple and easy way to detect HHT-related abnormalities during routine US examinations.

CONCLUSION

Hepatic US serves to diagnose the detailed complex hepatic changes typical of HHT, and contributes to increased diagnostic confidence of hepatic changes in HHT patients, with the most simple way not to overlook HHT-related abnormalities being to find hepatic artery dilatation.

Imaging of acute conditions affecting the hepatic vasculature

Liver imaging primarily consists of evaluating the parenchyma and biliary system. However, the liver has a rich, complex vascularity which can also be affected by numerous disease processes. By considering disease processes that primarily affect the hepatic veins, portal veins, and hepatic arteries, an anatomy-based approach of hepatic vascular diseases can be applied to image interpretation to allow rapid diagnosis and prompt initiation of treatment. Computed tomography, magnetic resonance imaging, and ultrasound are all effectively used to evaluate the liver and can play complimentary roles. In this article, the key imaging findings of acute conditions affecting the hepatic veins (passive congestion, acute thrombosis/Budd-Chiari, stenosis), portal veins (thrombosis, phlebitis, stenosis), hepatic arteries (laceration, pseudoaneurysm, thrombosis), and arteriovenous structures (hereditary hemorrhagic telangiectasis, arteriovenous fistula) will be reviewed.