Pulse-gated noncontrast thoracic magnetic resonance angiography for acute aortic dissection with transient ischemic attack: A case report

Aortic dissection is a rare cause of an acute ischemic stroke or transient ischemic attack (TIA). Aortic dissection is particularly challenging in stroke patients who are eligible for thrombolysis secondary to the diagnostic difficulty within a narrow time window (4.5 h) and have a risk of developing life-threatening hemorrhagic complications following thrombolysis. Computed tomographic angiography (CTA) has been the mainstay of imaging when evaluating acute aortic syndrome. However, it cannot be routinely performed for pregnant patients and those with renal failure or iodine-contrast media allergy. We report a case of a 72-year-old woman who developed transient right-hand paralysis without any chest symptoms. Brain magnetic resonance imaging (MRI) showed no recent infarction; however, the brachiocephalic trunk was not well visualized on carotid magnetic resonance angiography (MRA). Subsequent thoracic pulse-gated noncontrast three-dimensional balanced steady-state free precession MRA (bSSFP-MRA) detected a Stanford type A acute aortic dissection (TAAAD). This was confirmed by CTA, leading to the diagnosis of TIA due to Stanford TAAAD. Pulse-gated noncontrast thoracic bSSFP-MRA was acquired a few minutes after a series of brain MRI scans. This imaging modality is expected to be used as a screening platform to rule out Stanford TAAAD during the hyperacute phase of stroke.