Beschleunigung der kardiovaskulären MRT mittels paralleler Bildgebung: Grundlagen, praktische Aspekte, klinische Anwendungen und Perspektiven

Zusammenfassung

Moderne Verfahren der Magnetresonanztomographie (MRT) spielen eine zentrale Rolle für die nicht-invasive Diagnostik von Herz- und Gefäßerkrankungen. Kardiovaskuläre MRT erfordert eine sehr hohe Datenaufnahmegeschwindigkeit und Effektivität, deren Erfordernissen konventionelle MR-Datenakquisitionsstrategien nur eingeschränkt genügen. In diesen Strategien wird die Ortskodierung ausschließlich über eine sequenzielle Abfolge von Hochfrequenzimpulsen in Verbindung mit magnetischen Feldgradienten vorgenommen. Die parallele MRT (pMRT) umgeht diese Einschränkungen, indem zum Zweck der simultanen Ortskodierung zusätzlich das Signalintensitätsprofil von Hochfrequenzempfangsantennen benutzt wird. Der damit verbundene Geschwindigkeitszuwachs kann die kardiovaskuläre MR-Diagnostik auf vielfältige Weise verbessern: durch Verkürzung der Untersuchungszeiten, Verbesserung der räumlichen Auflösung bzw. ausreichende Abdeckung anatomischer Zielgebiete, Verbesserung der zeitlichen Auflösung, Erhöhung der Bildqualität, Überwindung physiologischer Grenzwerte, Detektion und Korrektur physiologischer Bewegungseinflüsse sowie Vereinfachung des Untersuchungsablaufes. Diese Übersichtsarbeit stellt für jede dieser Strategien Anwendungsbeispiele zur diagnostischen Bildgebung des Herzens und großer Gefäße vor. Zuvor wird eine Übersicht zu den wesentlichen Grundlagen der parallelen Bildgebung präsentiert. Anschließend werden elementare praktische Aspekte wie Einschränkungen im Signal-Rausch-Verhältnis, maßgeschneiderte Untersuchungsprotokolle und potenzielle Bildartefakte sowie klinische Anwendungsmöglichkeiten der parallelen Bildgebung in der kardiovaskulären MRT betrachtet. Abschließend werden aktuelle Forschungstrends und zukünftige Entwicklungen der kardiovaskulären MRT aus technischer und klinischer Sicht diskutiert.

Abstract

Cardiovascular Magnetic Resonance (CVMR) imaging has proven to be of clinical value for non-invasive diagnostic imaging of cardiovascular diseases. CVMR requires rapid imaging; however, the speed of conventional MRI is fundamentally limited due to its sequential approach to image acquisition, in which data points are collected one after the other in the presence of sequentially-applied magnetic field gradients and radiofrequency pulses. Parallel MRI uses arrays of radiofrequency coils to acquire multiple data points simultaneously, and thereby to increase imaging speed and efficiency beyond the limits of purely gradient-based approaches. The resulting improvements in imaging speed can be used in various ways, including shortening long examinations, improving spatial resolution and anatomic coverage, improving temporal resolution, enhancing image quality, overcoming physiological constraints, detecting and correcting for physiologic motion, and streamlining work flow. Examples of these strategies will be provided in this review, after some of the fundamentals of parallel imaging methods now in use for cardiovascular MRI are outlined. The emphasis will rest upon basic principles and clinical state-of-the art cardiovascular MRI applications. In addition, practical aspects such as signal-to-noise ratio considerations, tailored parallel imaging protocols and potential artifacts will be discussed, and current trends and future directions will be explored.

Key words

Cardiovascular MRI - parallel MR imaging - phased array technology - many element coil arrays

Literatur

• 1 Lima J A, Desai M Y. Cardiovascular magnetic resonance imaging: current and emerging applications.  J Am Coll Cardiol. 2004;  178 1164-1171
• 2 Danias P G, Stuber M, Botnar R M. et al . Coronary MR angiography clinical applications and potential for imaging coronary artery disease.  Magn Reson Imaging Clin N Am. 2003;  178 81-99
• 3 Sodickson D K, Manning W J. Simultaneous acquisition of spatial harmonics (SMASH): fast imaging with radiofrequency coil arrays.  Magn Reson Med. 1997;  178 591-603
• 4 Pruessmann K P, Weiger M, Scheidegger M B. et al . SENSE: sensitivity encoding for fast MRI.  Magn Reson Med. 1999;  178 952-962
• 5 Jakob P M, Griswold M A, Edelman R R. et al . Accelerated cardiac imaging using the SMASH technique.  J Cardiovasc Magn Reson. 1999;  178 153-157
• 6 Weiger M, Pruessmann K P, Boesiger P. Cardiac real-time imaging using SENSE. SENSitivity Encoding scheme.  Magn Reson Med. 2000;  178 177-184
• 7 Pruessmann K P, Weiger M, Boesiger P. Sensitivity encoded cardiac MRI.  J Cardiovasc Magn Reson. 2001;  178 1-9
• 8 Bammer R, Schoenberg S O. Current concepts and advances in clinical parallel magnetic resonance imaging.  Top Magn Reson Imaging. 2004;  178 129-158
• 9 Jakob P M, Griswold M A, Edelman R R. et al . AUTO-SMASH: a self-calibrating technique for SMASH imaging. SiMultaneous Acquisition of Spatial Harmonics.  Magn Reson Mater Phy. 1998;  178 42-54
• 10 Griswold M A, Jakob P M, Heidemann R M. et al . Generalized autocalibrating partially parallel acquisitions (GRAPPA).  Magn Reson Med. 2002;  178 1202-1210
• 11 Kyriakos W E, Panych L P, Kacher D F. et al . Sensitivity profiles from an array of coils for encoding and reconstruction in parallel (SPACE RIP).  Magn Reson Med. 2000;  178 301-308
• 12 Bydder M, Larkman D J, Hajnal J V. Generalized SMASH imaging.  Magn Reson Med. 2002;  178 160-170
• 13 Sodickson D K, McKenzie C A. A generalized approach to parallel magnetic resonance imaging.  Med Phys. 2001;  178 1629-1643
• 14 Pruessmann K P, Weiger M, Bornert P. et al . Advances in sensitivity encoding with arbitrary k-space trajectories.  Magn Reson Med. 2001;  178 638-651
• 15 Tsao J, Boesiger P, Pruessmann K P. k-t BLAST and k-t SENSE: dynamic MRI with high frame rate exploiting spatiotemporal correlations.  Magn Reson Med. 2003;  178 1031-1042
• 16 Madore B, Glover G H, Pelc N J. Unaliasing by fourier-encoding the overlaps using the temporal dimension (UNFOLD), applied to cardiac imaging and fMRI.  Magn Reson Med. 1999;  178 813-828
• 17 Madore B. UNFOLD-SENSE: a parallel MRI method with self-calibration and artifact suppression.  Magn Reson Med. 2004;  178 310-320
• 18 Kellman P, Epstein F H, McVeigh E R. Adaptive sensitivity encoding incorporating temporal filtering (TSENSE).  Magn Reson Med. 2001;  178 846-852
• 19 Kostler H, Sandstede J J, Lipke C. et al . Auto-SENSE perfusion imaging of the whole human heart.  J Magn Reson Imaging. 2003;  178 702-708
• 20 Tsao J. K-t SENSE for efficient dynamic parallel imaging by joint-space time consideration. Second International Workshop on Parallel MRI Zurich, Switzerland; Intl. Soc. Mag. Reson. Med. 2004: 51
• 21 Breuer F A, Kellman P, Griswold M A. et al . Dynamic autocalibrated parallel imaging using temporal GRAPPA (TGRAPPA).  Magn Reson Med. 2005;  178 981-985
• 22 Zhu Y, Hardy C J, Sodickson D K. et al . Highly parallel volumetric imaging with a 32-element RF coil array.  Magn Reson Med. 2004;  178 869-877
• 23 McKenzie C A, Yeh E N, Ohliger M A. et al . Self-calibrating parallel imaging with automatic coil sensitivity extraction.  Magn Reson Med. 2002;  178 529-538
• 24 Griswold M A, Jakob P M, Chen Q. et al . Resolution enhancement in single-shot imaging using simultaneous acquisition of spatial harmonics (SMASH).  Magn Reson Med. 1999;  178 1236-1245
• 25 Yang Q X, Wang J, Smith M B. et al . Reduction of magnetic field inhomogeneity artifacts in echo planar imaging with SENSE and GESEPI at high field.  Magn Reson Med. 2004;  178 1418-1423
• 26 Weiger M, Boesiger P, Hilfiker P R. et al . Sensitivity encoding as a means of enhancing the SNR efficiency in steady-state MRI.  Magn Reson Med. 2005;  178 177-185
• 27 Larkman D J, Atkinson D, Hajnal J V. Artifact reduction using parallel imaging methods.  Top Magn Reson Imaging. 2004;  178 267-275
• 28 Li B S, Mohan R A, Li W. et al .Single Breath-hold Whole-heart Inner Volume Black-blood Cardiac MRI using SSFSE with Parallel Imaging. Proceedings of the 12th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Kyoto, Japan; Intl. Soc. Mag. Reson. Med. 2004: 2252
• 29 Priatna A, Zhu D. Double/triple IR dual contrast FSE of the heart with ASSET. Proceedings of the 11th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Toronto, Ontario, Canada; Intl. Soc. Mag. Reson. Med. 2003: 1562
• 30 Gutberlet M, Spors B, Grothoff M. et al . Vergleich verschiedener kardialer MRT-Sequenzen bei 1.5 T/3.0 T bezüglich des Signal- und Kontrast-zu-Rausch-Verhältnisses - Erste Erfahrungen.  Fortschr Röntgenstr. 2004;  178 801-808
• 31 Mahnken A H, Gunther R W, Krombach G A. Grundlagen der linksventrikulären Funktionsanalyse mittels MRT und MSCT.  Fortschr Röntgenstr. 2004;  178 1365-1379
• 32 Noeske R, Messroghli D, Friedrich M G. et al .2D CINE FIESTA imaging for the assessment of cardiac function in combination with parallel imaging: a comparison study. Proceedings of the 11th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Toronto, Ontario, Canada; Intl. Soc. Mag. Reson. Med. 2003: 1563
• 33 Niendorf T, Noeske R, Friedrich M G. High speed valve tracking using 2DFIESTA CINE in conjunction with sensitivity encoding.  J Cardiovasc Magn Reson. 2004;  178 426
• 34 Rettmann D W, Saranathan M, Wu K C. et al .High temporal resolution breath-held 3D FIESTA CINE: Validation of ventricular function in patients with chronic myocardial infarction. Proceedings of the 12th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Kyoto, Japan; Intl. Soc. Mag. Reson. Med. 2004: 3823
• 35 Wintersperger B J, Nikolaou K, Dietrich O. et al . Single breath-hold real-time cine MR imaging: improved temporal resolution using generalized autocalibrating partially parallel acquisition (GRAPPA) algorithm.  Eur Radiol. 2003;  178 1931-1936
• 36 Li B, Chen Q, Li W. et al .Single-shot FIESTA Single-breath-hold Whole-heart MRI with 4X Parallel Imaging. Proceedings of the 11th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Toronto, Ontario, Canada; Intl. Soc. Mag. Reson. Med. 2003: 380
• 37 Zhang Q, Park J, Li D. et al .Improving True-FISP Parallel CINE imaging using a new data acquisition scheme for coil sensitivity calibration. Proceedings of the 11th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Toronto, Ontario, Canada; Intl. Soc. Mag. Reson. Med. 2003: 2329
• 38 Herzka D A, Derbyshire A, Kellman P. et al .Myocardial tagging in a single heart-beat with EPI-SSFP and TSENSE. 11th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Toronto, Ontario, Canada; Intl. Soc. Mag. Reson. Med. 2003: 374
• 39 Ryf S, Kozerke S, Boesiger P. 3DCSPAMM tagging accelerated with kt-BLAST. Proceedings of the 11th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Toronto, Ontario, Canada; Intl. Soc. Mag. Reson. Med. 2003: 1565
• 40 Kellman P, Larson A C, Zhang Q. et al .Cardiac CINE 3D true-FISP parallel imaging using auto-calibrating 2D TSENSE. Proceedings of the12th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Kyoto, Japan; Intl. Soc. Mag. Reson. Med. 2004: 2120
• 41 Kozerke S, Tsao J, Razavi R. et al . Accelerating cardiac cine 3D imaging using k-t BLAST.  Magn Reson Med. 2004;  178 19-26
• 42 Slavin G S, Wolff S D, Gupta S N. et al . First-pass myocardial perfusion MR imaging with interleaved notched saturation: feasibility study.  Radiology. 2001;  178 258-263
• 43 Kellman P, Derbyshire J A, Agyeman K O. et al . Extended coverage first-pass perfusion imaging using slice-interleaved TSENSE.  Magn Reson Med. 2004;  178 200-204
• 44 Kostler H, Ritter C, Lipp M. et al . Prebolus quantitative MR heart perfusion imaging.  Magn Reson Med. 2004;  178 296-299
• 45 Ablitt N A, Gatehouse P D, Firmin D N. et al . Respiratory reordered UNFOLD perfusion imaging.  J Magn Reson Imaging. 2004;  178 817-825
• 46 Kim R J, Fieno D S, Parrish T B. et al . Relationship of MRI delayed contrast enhancement to irreversible injury, infarct age, and contractile function.  Circulation. 1999;  178 1992-2002
• 47 Kellman P. Parallel methods for cardiac imaging. Second International Workshop on Parallel MRI Zurich, Switzerland; Intl. Soc. Mag. Reson. Med. 2004: 82
• 48 Kellman P, Larson A C, Hsu L Y. et al . Motion-corrected free-breathing delayed enhancement imaging of myocardial infarction.  Magn Reson Med. 2005;  178 194-200
• 49 Sommer T, Hofer U, Hackenbroch M. et al . Hochauflösende 3D-MR-Koronarangiographie inEcht-Zeit-Navigatortechnik: Ergebnisse aus107 Patientenuntersuchungen.  Fortschr Röntgenstr. 2002;  178 459-466
• 50 Niendorf T, Saranathan M, Lingamneni A. et al . Short breath-hold, volumetric coronary MR angiography employing steady-state free precession in conjunction with parallel imaging.  Magn Reson Med. 2005;  178 885-894
• 51 Walter C, Philippi G, Westerhausen R. et al . Hochauflösende Kontrastmittel-gestützte 3D-MR-Angiographie (MRA) der Nierenarterien mit paralleler Bildgebung (SENSE).  Fortschr Röntgenstr. 2003;  178 1244-1250
• 52 Ohno Y, Kawamitsu H, Higashino T. et al . Time-resolved contrast-enhanced pulmonary MR angiography using sensitivity encoding (SENSE).  J Magn Reson Imaging. 2003;  178 330-336
• 53 Sodickson D K, Hardy C J, Zhu Y. et al . Rapid volumetric MRI using parallel imaging with order-of-magnitude accelerations and a 32-element RF coil array: feasibility and implications.  Acad Radiol. 2005;  178 626-635
• 54 Niendorf T, McKenzie C A, Spencer M. et al .Image quality improvements in whole body MRA of the aorta by employing accelerated, non-contrast enhanced, cardiac gated 3D SSFP. Proceedings of the 12th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Kyoto, Japan; Intl. Soc. Mag. Reson. Med. 2004: 2570
• 55 Weiger M, Pruessmann K P, Boesiger P. 2D SENSE for faster 3D MRI.  Magn Reson Mater Phy. 2002;  178 10-19
• 56 Ohliger M A, Grant A K, Sodickson D K. Ultimate intrinsic signal-to-noise ratio for parallel MRI: electromagnetic field considerations.  Magn Reson Med. 2003;  178 1018-1030
• 57 Hardy C J, Giaquinto R A, Cline H. et al .A 32-element cardiac receiver coil array for highly accelerated parallel imaging. Proceedings of the 13th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Miami, Florida, Hawaii; Intl. Soc. Mag. Reson. Med. 2005: 951
• 58 Niendorf T, Hardy C J, Cline H. et al .Highly accelerated single breath-hold coronary MRA with whole heart coverage using a cardiac optimized 32-element coil array. Proceedings of the 13th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Miami, Florida, USA; Intl. Soc. Mag. Reson. Med. 2005: 702
• 59 Quick H H, Vogt F M, Maderwald S. et al . Hochauflösende Ganzkörper-Magnetresonanzangiographie mit paralleler Bildgebung: Erste Erfahrungen.  Fortschr Röntgenstr. 2004;  178 163-169
• 60 Keupp J, Aldefeld B, Bornert P. Continuously moving table SENSE imaging.  Magn Reson Med. 2005;  178 217-220
• 61 Weber O M, Martin A J, Higgins C B. Whole-heart steady-state free precession coronary artery magnetic resonance angiography.  Magn Reson Med. 2003;  178 1223-1228
• 62 Niendorf T, Sodickson D K, Hardy C J. et al .Towards whole heart coverage in a single breath-hold: coronary artery imaging using a true 32-channel phased array MRI system. Proceedings of the 12th Scientific Meeting of the International Society for Magnetic Resonance in Medicine Kyoto, Japan; Intl. Soc. Mag. Reson. Med. 2004: 703
• 63 Nehrke K, Bornert P, Stehning C. et al .Free breathing whole heart coronary angiography on a clinical scanner in less than 4 minutes. Proceedings of the 13th Scientific Meeting of the International Society of Magnetic Resonance in Medicine Intl. Soc. Mag. Reson. Med. 2005: 704