Background Aortic Atheroma (AoA) is an independent risk factor for new and recurrent stroke. ulceration (≥ 2 mm) and BI 2536 mobility of AoA were assessed in the proximal (ascending and proximal arch) and distal (distal arch and descending) segments of thoracic aorta by a cardiologist to interpret the TEE and a radiologist to interpret the cMRI. There was good correlation between cMRI and TEE in measurement of plaque thickness in the proximal segments (R=0.73 p<0.0001) and the distal segments (R=0.81 p<0.0001) of the aortic arch (AA). cMRI had a high degree of accuracy in detecting measurable AoA (≥ Thbs2 1 mm) in the proximal segments (sensitivity 90% specificity 100%) as well as the distal segments (sensitivity 67% specificity 100%). cMRI also had a high degree of accuracy in detecting significant AoA (≥ 4 mm) in proximal segments (sensitivity 71% specificity 93%) as well as distal segments (sensitivity 71% specificity 100%). Conclusion The study showed a high degree of accuracy and correlation of AoA detected and measured by cMRI as compared to TEE in patients with recent stroke/TIA. This technique has limitations in detection of AoA ulceration and protocols assessing AoA mobility need to be developed. and and p-value <0.001) of the aortic arch (Figures 1 and ?and2).2). cMRI detected of proximal segment measurable AA disease ≥ 1 mm BI 2536 in thickness with 90% sensitivity and 100% specificity. In distal segments of the aortic arch the sensitivity was 67% and specificity was 100%. cMRI detected severe AoA disease (≥ 4 mm in thickness) in proximal segments of the aortic arch with 71% sensitivity and BI 2536 93% specificity. In the distal aortic arch the technique was 71% specific and 100% sensitive. cMRI was able to identify 89% of proximal aorta ulcerations and 64% of distal aorta ulcerations (Figure 3). The mobility of plaques could not be assessed with this protocol. Figure 1 AAPT correlation in proximal segments. Figure 2 AAPT correlation in distal segments. Figure 3 AA ulceration seen on cMRI and TEE. Discussion It has been shown that aortic atheromatous (AoA) disease may be found in 16-20% of patients with transient ischemic attack (TIA) or stroke and a number of prospective studies have confirmed a strong association between stroke and AoA plaques [7 8 17 Sen et al.  found a high rate of progression of aortic atheroma in 28% of ischemic stroke/TIA patients using transesophageal echocardiography (TEE) which is considered the gold standard for detection of AoA plaque in this setting . TEE is widely available produces images of greater resolution than transthoracic echocardiography (TTE) and has high inter-reader reproducibility [23 24 However TEE has significant limitations. It is semi-invasive requires conscious sedation and carries risk of damage to the esophagus albeit low . Patient tolerability may be a problem ; a relatively large number of individuals refused a follow-up TEE after a 12 month interval in one series . Because of the semi-invasive nature of the study patients for TEE should be hemodynamically stable. Many patients with stroke have difficulty in swallowing  and BI 2536 thus may have difficulty swallowing the transducer. Air artifact and insonation angles can interfere with visualization in proximal [15 24 and distal aortic arch . A failure to reliably assess the aortic arch because of insufficient visualization was noted in one study in about half the patients tested; it was shown that TEE may underestimate AoA disease . Difficulties with plaque thickness measurement and gradation scoring by TEE at precise locations in baseline and follow-up measurements was a limiting factor in a study of progression of AoA disease and risk of stroke . Cardiovascular magnetic resonance imaging (cMRI) of the thoracic aorta has been shown to have unique characteristics which may improve the potential for identifying BI 2536 the source of cryptogenic stroke; about 21% of a group of patients with stroke of undetermined etiology were found to have AoA disease with embolic potential which was not detected by TEE . The development of new protocols for cMRI to.