MDCT findings of aortic branch artery pseudoaneurysms associated with type B intramural haematoma

Purpose The purpose of this study was to evaluate prevalence, morphological characteristics and evolution of aortic branch artery pseudoaneurysms associated with type B aortic intramural haematoma (IMH) using multidetector computed tomography (MDCT). Materials and methods We enrolled 14 patients (nine men; mean age 64.6±9.6; range 42–75 years) with a diagnosis in the acute phase of type B IMH without evidence of intimal tear. All patients underwent clinical and MDCT follow-up. Results Twenty-two pseudoaneurysms in six patients (6/14, 43%) were observed at MDCT. In the majority of patients (5/6, 83%) the pseudoaneurysms were multiple and involved the branches of the descending thoracic aorta (14/22, 64%), mainly the intercostal arteries (11/22, 50%). At a mean follow-up of 10.6±8.7 months, 21 pseudoaneurysms showed resolution, reduction or dimensional stability (95%), whereas only one increased in size (5%). Conclusions Aortic branch artery pseudoaneurysms associated with IMH may be considered a benign disease, as the majority of cases resolved or did not change in size, with haematoma resorption. However, because a dynamic change in pseudoaneurysms in the acute and subacute phases was frequently observed, close clinical and imaging follow-up is mandatory.