Comparison between MR and CT for spinal cord angiography application
| Item | MR Angiography | CT Angiography |
|---|---|---|
| Efficacy for AKA detection | High, ≤100 % | High, ≤100 % |
| Validation with catheter angiography | Realized in patients suspected of spinal vascular disease27 | To be demonstrated |
| Differentiation of inlet artery from outlet vein | Possible with dynamic multiphase imaging | Not demonstrated yet, may require table movement |
| Anatomy (vertebrae) | Second phase required | Adequately covisualized |
| Voxel size | In-plane, 0.8 × 0.8 mm, Section thickness, 1.2 mm | In-plane, 0.34 × 0.34 mm, Collimation width, 0.6 mm |
| Spatial coverage | Standard T5 to L5, craniocaudal FOV ≤50 cm, other directions (AP or RL) limited | Entire spine is possible |
| Scan duration (ie, temporal resolution) | Down to 8 seconds, with limited spatial coverage25 | Down to 6.5 seconds, with large spatial coverage45 |
| Patient size | Independent image quality | Contrast-to-noise of vessels decreases for corpulent patients45 |
| Safety | Very small risk of NSF due to Gd-based contrast agent; reduces fluoroscopy time and iodinated contrast volume in subsequent catheter angiography | Ionizing radiation, potentially nephrotoxic contrast agent |
| Contrast agent | 0.2–0.3 mmol Gd-chelate/kg | 40–150 mL iodine compound |
| Exam time | 30–45 minutes | 10–15 minutes |
| Logistics | Scheduling required for TAAA patients; MR imaging is already part of diagnosis in patients suspected for spinal cord vascular lesions | Already part of preclinical work-up in TAAA patients |
Note:—AKA indicates Adamkiewicz artery; T5, fifth thoracic vertebral level; L5, fifth lumbar vertebral level; AP, anteroposterior; RL, right-left; TAAA, thoracoabdominal aortic aneurysm; NSF, nephrogenic sclerotic fibrosis; Gd, gadolinium.