Preoperative mapping of arterial spinal supply using 3.0-T MR angiography with an intravasal contrast medium and high-spatial-resolution steady-state

Abstract

Introduction: Preoperative mapping of the arterial spinal supply prior to thoracoabdominal aortic aneurysm repair is highly relevant because of high risk for postoperative ischemic spinal cord injuries such as paraparesis or paraplegia.

Methods: Twenty-four consecutive patients prior to surgical thoracoabdominal aortic aneurysm repair were investigated. All patients underwent steady-state MR angiography (MRA) of the spinal vasculature with 3-T MRI. The sequence used was a steady-state coronary 3D FLASH with 0.7-mm isotropic voxels. MRA was performed using an intravasal contrast agent. Studies were evaluated by three readers including delineation of arterial spinal supply including both aortic origin and spinal canal entry by three readers.

Results: Identification and localization of the Adamkiewicz artery and its spinal canal entry was successful in all patients. Overall depiction of the vascular anatomy was graded as very good in 3 (12.5%), good in 14 (58.4%), sufficient in 5 (20.8%), and poor in 2 (8.3%) patients. Depiction of segmental artery aortic exit level was graded as good in 6 (25.0%), sufficient in 10 (41.7%), poor in 4 (16.7%) and not identifiable in 4 (16.7%) patients. Delineation of segmental artery entry level into the spinal canal was graded as very good in 4 (16.7%), good in 11 (45.8%), sufficient in 6 (25.0%), and poor in 3 (12.5%) patients.

Conclusions: The use of 3-T MRA with an intravascular contrast agent and steady-state enables AKA localization including its segmental arteries with regard to the level of aortic origin and spinal canal entry in most patients.