Multi-detector row CT angiography with direct intra-arterial contrast injection for the evaluation of neurovascular disease: technique, applications, and initial experience

Abstract

The purpose of this study was to evaluate the usefulness of 64-section multi-detector row CT angiography (CTA) with direct intra-arterial contrast injection (IA-CTA) for the evaluation of neurovascular disease. This technique was used in 11 patients at our institution. All studies were technically successful, and there were no complications. Small vascular malformations were mapped easily on high-resolution IA-CTA images, enabling microsurgical resection or stereotactic radiosurgery. In a similar fashion, additional morphologic features were revealed on IA-CTA images not seen on standard 2D and 3D digital subtraction angiography. Of 11 patients undergoing IA-CTA, 7 patients had further anatomic clarity of the small arteriovenous fistula/malformation and 4 patients had changes in the treatment plan on the basis of the IA-CTA findings.

Fig 1.

Patient 7. This patient presented with acute onset of left leg numbness. A, A noncontrast CT scan demonstrates a small bleed in the right parietal lobe. B, An oblique, magnified image of cerebral DSA reveals a tiny pial AVF (black arrow) drained by an early filling cortical vein (white arrows). Given the fairly superficial location of the lesion and recent history of bleed, surgical resection was recommended. C, A source image of IA-CTA reveals the point of connection between the parietal branch of the right anterior cerebral artery (arrow) and adjacent cortical vein. D, 3D volume-rendered images reveal the feeding artery, fistula, and the draining vein (labeled blue). The knowledge of the cross-sectional anatomy helped significantly when planning surgical approach. This lesion could be easily found, confirmed at surgery, and clipped.

Fig 2.

Patient 10. This patient is a 50-year-old-woman who presented at our emergency department with diffuse SAH. A, Lateral view of the LICA demonstrates a multilobulated, complex aneurysm. B, 3D DSA reveals that the posterior communicating artery is originating from the aneurysmal neck (black arrowhead). Even on 3D imaging, the origin of the anterior choroidal artery (white arrows) cannot be located in relationship to the aneurysmal neck. C, A 3D IA-CTA clearly reveals that the anterior choroidal artery (white arrows) arises from the proximal aneurysmal dome. D, Magnified axial source image reveals the supraclinoid internal carotid artery anteriorly (black arrowheads). The anterior choroidal artery origin from the dome of the aneurysm is again easily identified. This excluded endovascular management, and this aneurysm was surgically clipped.

Fig 3.

Patient 9. This patient is a 56-year-old man who presented with acute-onset headache and sudden neurologic deficits. A, Noncontrast CT scan demonstrates a focal hematoma in the midbrain. B, A high-frame rate DSA image of a left vertebral angiogram reveals small branches of the superior cerebellar artery in the region of the midbrain with an adjacent, early filling superior vermian vein (arrow). However, it could not be inferred with certainty whether this lesion is a fistula or a true AVM. C, A source image of IV-CTA reveals an abnormal, early filling superior vermian vein (arrow), but the nidus of the AVM is very difficult to identify. D, Source image of IA-CTA clearly demonstrates the nidus of a micro-AVM (arrows) in the region of the midbrain tectum as well as multiple tiny arterial feeders. The IA-CTA was considered superior to DSA as well as to IV-CTA in mapping as well as characterization of this tiny AVM. Wider window settings are intentionally used to demonstrate the individual tiny branches supplying this lesion.