What are the options if the patient cannot receive intravenous gadolinium based or iodinated contrast material?
This depends on the clinical question. Unenhanced CT can still be useful to detect ruptured aortic pathology, intramural hematoma, and stigmata of mesenteric ischemia in the bowel. However, it cannot generally detect an aortic dissection, and it cannot assess vessel patency, vessel wall abnormalities, or vascular graft dehiscence.
On magnetic resonance imaging (MRI), vascular assessment without intravenous contrast material is still possible using one or more of the following image sequences:
- • Time of flight (TOF) images.
- • Phase contrast (PC) images.
- • Arterial spin labeled (ASL) images.
- • Balanced steady state free precession images.
