6533b7d2fe1ef96bd125df40

RESEARCH PRODUCT

Erfahrungen mit einer 3D-Navigatorsequenz zur Koronargefäßdarstellung an einem Hochleistungs-MR-System

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Purpose: To evaluate MR coronary angiography using a three-dimensional navigator echo sequence on a MR scanner with a high performance gradient system. Material and Methods: Five healthy volunteers were examined with a 1.5 Tesla MR system, using a high performance prototype gradient system (peak amplitude 50 mT/m, rising time 600 μs). For imaging, a navigated gradient-echo pulse sequence with an in-plane resolution between 0.63 × 0.63 and 0.78 × 0.78 mm 2 was used. Per patient two overlapping slabs were acquired. The number of visualised coronary artery segments was estimated (AHA classification). In addition, signal-to-noise measurements were performed in the ascending aorta at the level of the proximal right and left coronary arteries. Results: In all volunteers the left main, the right coronary artery up to segment 3, the LAD up to segment 8 and the RCX with segment 11 and 13 were clearly visualised. The average signal-to-noise value at the level of the right coronary artery was 11.4 ± 5.0, at the level of the left coronary artery 12.3 ± 4.5. One volunteer was measured with an in-plane resolution of 0.63 × 0.63 mm 2 . This resulted in a too low signal-to-noise ratio so that an adequate assessment of coronary arteries was no longer possible. Conclusion: 3D-MR coronary angiography using the navigator technique is limited by the signal-to-noise ratio.