Multiphase multidetector-row computed tomographic and ultrasonographic findings in dogs with spontaneous liver lobe torsion

Liver lobe torsion (LLT) is an uncommon condition of unknown origin in dogs. Several reports describe the clinical features and outcome, but only few of them include the imaging characteristics of this disease. The aim of this descriptive case series was to describe the ultrasonographic (US) and multidetector-row computed tomographic (MDCT) features of LLT in a group of dogs. Five dogs were included in this single-center descriptive study, having both US, CT and surgical and histological confirmation of LLT available for review. Different US appearances have been found, both hypoechoic and hyperechoic liver lobes and heterogeneous mass-like lesions, with fluid and gas content. At three-phase MDCT examination, LLT appeared as fluid- and gas-filled lesions (consistent with abscess transformation), or as hypoattenuating hypovascular lobes. Two different vascular signs were also described: whirl sign or vascular interruption were seen in all cases, allowing a correct pre-surgical diagnosis in all the cases presented. Multiphase MDCT was a helpful imaging method for the correct pre-surgical diagnosis of LLT in dogs, and its use in the suspected cases is therefore advisable.