Three-dimensional rotational spinal angiography in the evaluation and treatment of vascular malformations

Abstract

Background and purpose: Conventional spinal angiography, although useful in providing angioarchitectural details of spinal vascular disease, has limitations. The advent of 3D angiography has provided a better comprehension of angioarchitectural detail when evaluating the intracranial circulation. The purpose of this study was to evaluate the usefulness of 3D angiography in the diagnosis and treatment of vascular malformations of the spine.

Methods: This retrospective analysis included 17 3D spinal angiograms acquired in 14 consecutive patients examined at our institution for a spinal vascular lesion, which included nine spinal cord arteriovenous malformations (AVMs), one perimedullary arteriovenous fistula (AVF), three spinal dural AVFs, and one nerve root AVM. 3D angiography was obtained with apnea under general anesthesia by using a 14-second acquisition and 200 degrees rotation of the gantry during injection of 300 mg I/mL nonionic contrast material at a rate of 0.5-3.5 mL/s. Multiple reconstructed images were obtained with or without opacification of the surrounding structures. These images were then evaluated by the interventionalists at the time of the procedure and compared with findings obtained by conventional subtraction angiography.

Results: 3D angiography was useful in differentiating intramedullary lesions from perimedullary surface lesions; detecting arterial, nidal, or venous aneurysms; and evaluating the 3D structure of the lesion as well as the relationship between the malformation and its draining veins or surrounding bony structures. In specific situations, it obviated the need for contrast-enhanced conventional or 3D CT, as well as for lateral or oblique angiographic views, which are sometimes difficult to obtain with good quality. No 3D angiography-related complications were experienced. Some limitations in the definition of small vessel anatomy in the reconstructed images were noted.

Conclusion: In this small series of patients, 3D angiography was safe and useful for evaluation of the 3D vascular anatomy of spinal vascular malformations.

Fig 1.

Patient 8, 54-year-old male patient with spinal dural AVF. A, Unsubtracted anteroposterior (AP) (left) and subtracted lateral (right) spinal angiograms of left T12 intercostal artery show the spinal dural fistula. (arrow [AP projection], angiographic catheter; double arrow [AP projection], site of fistula at the dural sleeve; arrowhead [AP and lateral projection], anterior draining spinal vein). B, 3D reconstruction of T12 intercostal rotational injection with partial opacification of the spinal column shows the site of the fistula (double arrow) in relation to the venous drainage (arrowhead). C, Computer-generated rotation of the reconstructed image with a thin region of interest allows for a better demonstration of the fistula entering the intervertebral foramen. D, Lateral projection of the 3D-reconstructed rotational image after successful obliteration of the fistula. E, Similar view as in C, with the glue cast seen entering the spinal canal via the intervertebral foramen (double arrow).

Fig 2.

Patient 4, 26-year-old female patient with spinal cord AVM. A, AP (left) and lateral (right) subtracted spinal angiograms from the left T10 intercostal artery, demonstrating the supply to this conus AVM from the anterior spinal artery (arrow [AP projection]). Lazorthe’s basket is identified at the tip of the conus (double arrows [AP and lateral projections]). B, 3D-RSA in the lateral projection shows several feeders to this primarily superficial pial malformation (arrow).

Fig 3.

Patient 1, 20-year-old male patient with spinal cord AVM. A, Lateral spinal angiogram of the left vertebral artery for this cervical AVM with contribution from multiple cervical levels. B, 3D-RSA in the same projection as the prior study with enhanced detail in the course of the various feeding vessels. Note the depth of field created by the shadowing techniques provided in the software.

Fig 4.

Patient 13, 51-year-old female patient with spinal cord AVM. A, AP vertebral injection demonstrating supply to this cervical AVM from anterior and posterior spinal arteries. Note the duplication of the anterior spinal artery revealed by this view (arrow). B, Lateral projection in the early (left) and late (right) arterial phases demonstrating the anterior spinal artery (arrow [early phase]) and the posterior draining vein (double arrows [late phase]). C, 3D-RSA of the vertebral artery injection demonstrating resolution of fine details as depicted by the presence of the duplicated anterior spinal artery (arrow). Note the presence of the nidal aneurysm (double arrow).