Direct coronary motion extraction from a 2D fat image navigator for prospectively gated coronary MR angiography.

PURPOSE: Direct 2D tracking of cardiac motion may provide superior respiratory navigator gating for coronary magnetic resonance angiography compared to conventional liver-diaphragm navigators. However, additional 2D processing for motion extraction is unsuitable for real-time prospective gating. In this work, a 2D fat-selective image navigator, which delineates the epicardial fat surrounding coronary arteries, is developed to directly monitor epicardial fat motion at every heartbeat in real-time for prospective gating. METHODS: The proposed navigator is incorporated into a real-time interactive software that allows rapid setup and efficient motion extraction, and runs on standard clinical hardware without any additional dedicated components for processing. The proposed 2D cardiac fat image navigator was compared with the conventional 1D diaphragm navigator in free-breathing b-SSFP coronary MRAs in 12 healthy volunteers at 1.5T. RESULTS: Real-time motion extraction from 2D cardiac fat navigator images was feasible within 20 ms, enabling successful prospectively gated coronary magnetic resonance angiographies in all subjects. Compared to 1D diaphragmatic navigator, 2D fat image navigator reduced scan time by 38% (P < 0.0005), and significantly improved vessel sharpness, myocardial suppression, and image quality (P < 0.05). CONCLUSION: This demonstrates the feasibility of a 3D SSFP coronary magnetic resonance angiography sequence using a 2D epicardial fat image as a navigator for real-time prospective motion tracking.

Takayasu arteritis presenting in the context of active tuberculosis: a pediatric case.

Takayasu arteritis (TA) is a large-vessel vasculitis, most commonly presenting in young adults and more rarely in pediatric patients. An apparent association between TA and Mycobacterium tuberculosis has been noted previously, although this potential relationship is not yet understood. We present the case of a 16-year-old Haitian girl diagnosed with TA, originally presenting in the context of active tuberculosis. Our patient has been treated with antituberculosis therapy, corticosteroids, methotrexate, and rituximab to control her continued active vasculitis. With this case report, we seek to promote further exploration of the apparent association between TA and tuberculosis, as further clarification of the nature of this relationship may lead to the development of more targeted therapies and better outcomes for TA patients.