Spiral CT-angiography of the aorta

Abstract

To determine whether the new technique of CT-angiography was accurate in displaying the complex anatomy of the aorta and its major branches. Seventeen patients with a variety of aortic pathology were examined. Using a spiral CT-scanner a volumetric scan was made during injection of 150 cc of i.v. contrast. Depending on the chosen CT technique, a body volume with a length ranging between 25-100 cm could be examined in one 50 second spiral scan. On the resulting transverse slices vascular lumina and extent of thrombus were studied. Subsequently, the transverse slices were reconstructed in the coronal or sagittal plane in order to appreciate the craniocaudal relations of the vascular anatomy. Finally, three-dimensional reconstructions were made of vascular lumina and thrombus. In aortic aneurysms the extent of the aneurysmal dilatation and of the adherent thrombus could be accurately located relative to the origins of renal and visceral branches proximally, and iliac bifurcation distally. In cases of severe elongation, dissection or complex anatomy, a detailed preoperative insight into the individual anatomy could be obtained. The two-dimensional axial and multiplanar reconstructions offered excellent anatomic detail. The three-dimensional reconstructions, being based on a considerable data reduction, offered an efficient means of providing an overall view of complex anatomic relations. The advantage of CT-angiography is that, based on a single spiral scan, the vascular structures in the examined body volume can be displayed in any desired plane using multiplanar reconstructions. Alternatively, three-dimensional renderings can be created. The combination of multiplanar reconstructions and three-dimensional reconstructions makes CT-angiography an accurate technique for displaying even the most complex aortic anatomy.