Morphologic Evaluation of Ductus Diverticulum Using Multi - Detector Computed Tomography: Comparison with Traumatic Pseudoaneurysm of the Aortic Isthmus

Abstract

ObjectivesTo evaluate morphologic variations at the aortic isthmus with particular attention to ductus diverticulum, a mimicker of traumatic pseudoaneurysm, and to describe differences using Computed Tomography (CT) images.Patients and MethodsFrom December 2013 to December 2014, patients who underwent a chest CT examination after blunt trauma at our emergency department were included. Aortic isthmus morphologies were evaluated using multiplanar reconstruction (MPR) and maximum intensity projection (MIP) images as follows. Type I -concave contour, type II -convexity without a discrete bulge, or type III -a discrete focal bulge (defined as ductus diverticulum).ResultsAfter excluding 11 cases of traumatic pseudoaneurysm of the aortic isthmus, a total of 432 trauma patients (mean age = 47.1 ± 19.1 years, number of males = 318) were evaluated for aortic isthmus morphology, and classified as follows; type I (n = 240, 55.6%), type II (n = 157, 36.3%), and type III (n = 35, 8.1%). As compared with traumatic pseudoaneurysm (n = 11), ductus diverticulum had a smaller vertical diameter (5.5 ± 1.3 mm vs. 11.2 ± 2.7 mm, P < 0.001), a broader base (14.9 ± 4.1 mm vs. 8.8 ± 4.5 mm, P < 0.001), a smoother margin (97.1% vs. 27.3%, P < 0.001), and formed obtuse angle with the aortic wall. Furthermore, ductus diverticulum was not associated with the presence of a dissection flap or hemomediastinum.ConclusionDuctus diverticulum, a mimicker of traumatic pseudoaneurysm of the aortic isthmus, is a frequently observed anatomic variant during CT examinations. Familiarity with its CT imaging findings could avoid it being confused with traumatic pseudoaneurysm in blunt trauma patients.

Cross-sectional imaging of thoracic traumatic aortic injury

“…monly mistaken for TAI (ESM 6). The main features distinguishing this entity from a pseudoaneurysm include a wide base (vs. narrow neck for pseudoaneurysm), an obtuse margin relative to the wall of the aorta [62], and a smooth border [63]. The presence of other abnormalities such as an intimal fl ap or mediastinal hematoma also favor pseudoaneurysm.…”

Successful endovascular coil embolization of large pseudoaneurysm of ductus arteriosus diverticulum

“…DAD of the thoracic aorta is a common anatomic embryologic remnant of the ductus arteriosus (Lund et al, 1991). In adults, the reported prevalence of a ductus diverticulum using either catheter directed thoracic angiography or CT angiography is 9-26% (Morse et al, 1988;Hyung Ann et al, 2016). A histopathologic analysis suggested an incidence of up to 44% in adults (Vogler et al, 2007).…”

“…A histopathologic analysis suggested an incidence of up to 44% in adults (Vogler et al, 2007). The primary differential diagnosis of a ductus diverticulum is that of a traumatic thoracic pseudoaneurysm (Hyung Ann et al, 2016). CTA criteria that favor a diverticulum include smaller diameter, obtuse angles with smooth margins, and absence of additional traumatic findings such as aortic dissection flap or hemomediastinum (Hyung Ann et al, 2016).…”

Adult Onset Dysphagia: Right Sided Aortic Arch, Ductus Diverticulum, and Retroesophageal Ligamentum Arteriosum Comprising an Obstructing Vascular Ring

“…High resolution CT angiography with contrast and poststudy 3-dimensional reconstruction of the anatomy helped us reach the diagnosis in our case. Multidetector Computed Tomography (MDCT) has been described to differentiate a ductus diverticulum from aneurysms [5]. …”