Local SAR in parallel transmission pulse design

Magnetic Resonance in Medicine

Volumn 67, Issue 6, 2012, Pages 1566-1578

  Lee, Joonsung ^a   Gebhardt, Matthias ^b   Wald, Lawrence L ^c,d   Adalsteinsson, Elfar ^a,d  

^a Department of Electrical Engineering and Computer Science   (United States)

^b SIEMENS AG   (Germany)

^c MASSACHUSETTS GENERAL HOSPITAL   (United States)

^d MASSACHUSETTS INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

local SAR; parallel transmission; pTx RF design

Indexed keywords

ELECTROMAGNETIC FIELD EFFECTS; MAGNETIC RESONANCE IMAGING; NUMERICAL METHODS; RADIO TRANSMISSION; SPATIAL DISTRIBUTION; TRANSMISSIONS;

FUNDAMENTAL CONSTRAINTS; LOCAL SAR; PARALLEL TRANSMISSION; RADIO FREQUENCY PULSE; RF DESIGN; SINGLE CHANNEL SYSTEM; SPECIFIC ABSORPTION RATE; TRANSMISSION ARRAYS;

DESIGN;

ALGORITHM; ARTICLE; HEAD; IN VIVO STUDY; MATHEMATICAL ANALYSIS; MATHEMATICAL COMPUTING; MATHEMATICAL MODEL; NUCLEAR MAGNETIC RESONANCE IMAGING; PERFORMANCE; RADIOFREQUENCY; SIMULATION;

EID: 84861233288     PISSN: 07403194     EISSN: 15222594     Source Type: Journal    
DOI: 10.1002/mrm.23140     Document Type: Article

References (41)

1. Alagappan V, Nistler J, Adalsteinsson E, Setsompop K, Fontius U, Zelinski A, Vester M, Wiggins GC, Hebrank F, Renz W, Schmitt F, Wald LL,. Degenerate mode band-pass birdcage coil for accelerated parallel excitation. Magn Reson Med 2007; 57: 1148-1158.
2. Katscher U, Bornert P, Leussler C, van den Brink JS,. Transmit SENSE. Magn Reson Med 2003; 49: 144-150.
3. Setsompop K, Alagappan V, Gagoski B, Witzel T, Polimeni J, Potthast A, Hebrank F, Fontius U, Schmitt F, Wald LL, Adalsteinsson E,. Slice-selective RF pulses for in vivo B1+ inhomogeneity mitigation at 7 tesla using parallel RF excitation with a 16-element coil. Magn Reson Med 2008; 60: 1422-1432.
4. Setsompop K, Alagappan V, Gagoski BA, Potthast A, Hebrank F, Fontius U, Schmitt F, Wald LL, Adalsteinsson E,. Broadband slab selection with B1+ mitigation at 7T via parallel spectral-spatial excitation. Magn Reson Med 2009; 61: 493-500.
5. Setsompop K, Wald LL, Alagappan V, Gagoski B, Hebrank F, Fontius U, Schmitt F, Adalsteinsson E,. Parallel RF transmission with eight channels at 3 Tesla. Magn Reson Med 2006; 56: 1163-1171.
6. Setsompop K, Wald LL, Alagappan V, Gagoski BA, Adalsteinsson E,. Magnitude least squares optimization for parallel radio frequency excitation design demonstrated at 7 Tesla with eight channels. Magn Reson Med 2008; 59: 908-915.
7. Ullmann P, Junge S, Wick M, Seifert F, Ruhm W, Hennig J,. Experimental analysis of parallel excitation using dedicated coil setups and simultaneous RF transmission on multiple channels. Magn Reson Med 2005; 54: 994-1001.
8. Wiggins G, Mareyam A, Setsompop K, Alagappan V, Potthast A, Wald L,. A close-fitting 7 Tesla 8 channel transmit/receive helmet array with dodecahedral symmetry and B1 variation along Z. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Toronto, Canada; 2008. p 148.
9. Zhu Y,. Parallel excitation with an array of transmit coils. Magn Reson Med 2004; 51: 775-784.
10. IEC Standard 60601-2-33, Particular requirements for the safety of magnetic resonance equipment for medical diagnosis. Chicago: International Electrotechnical Commission; 2004.
11. International Electrotechnical Commission. International standard, Medical equipment-part 2: particular requirements for the safety of magnetic resonance equipment for medical diagnosis, 2nd revision., Geneva: International Electrotechnical Commission; 2002. pp 29-31.
12. Center for Devices and Radiologic Health, Guidance for the submission of premarket notifications for magnetic resonance diagnostic devices. Rockville, MD: Food and Drug Administration; 1998.
13. Voigt T, Doessel O, Katscher U,. Imaging conductivity and local SAR of the human brain. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Honolulu, Hawaii; 2009. p 4531.
14. Cloos MA, Bonmassar G,. Towards Direct B1 Based Local SAR Estimation. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Honolulu, Hawaii; 2009. p 3037.
15. Collins CM, Li S, Smith MB,. SAR and B1 field distributions in a heterogeneous human head model within a birdcage coil. Specific energy absorption rate. Magn Reson Med 1998; 40: 847-856.
16. Collins CM, Smith MB,. Calculations of B1 distribution, SNR, and SAR for a surface coil adjacent to an anatomically-accurate human body model. Magn Reson Med 2001; 45: 692-699.
17. Zelinski AC, Angelone LM, Goyal VK, Bonmassar G, Adalsteinsson E, Wald LL,. Specific absorption rate studies of the parallel transmission of inner-volume excitations at 7T. J Magn Reson Imaging 2008; 28: 1005-1018.
18. Xu D, King KF, Zhu Y, McKinnon GC, Liang ZP,. Designing multichannel, multidimensional, arbitrary flip angle RF pulses using an optimal control approach. Magn Reson Med 2008; 59: 547-560.
19. Xu D, King KF, Zhu Y, McKinnon GC, Liang ZP,. A noniterative method to design large-tip-angle multidimensional spatially-selective radio frequency pulses for parallel transmission. Magn Reson Med 2007; 58: 326-334.
20. Mao W, Smith MB, Collins CM,. Exploring the limits of RF shimming for high-field MRI of the human head. Magn Reson Med 2006; 56: 918-922.
21. Gumbrecht R., Lee J., Fautz H.-P., Diehl D., E. A. Fast high-flip pTx pulse design to mitigate B1+ inhomogeneity using composite pulses at 7T. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Stockholm, Sweden; 2010. p 101.
22. Grissom WA, Xu D, Kerr AB, Fessler JA, Noll DC,. Fast large-tip-angle multidimensional and parallel RF pulse design in MRI. IEEE Trans Med Imaging 2009; 28: 1548-1559.
23. Grissom W, Yip CY, Zhang Z, Stenger VA, Fessler JA, Noll DC,. Spatial domain method for the design of RF pulses in multicoil parallel excitation. Magn Reson Med 2006; 56: 620-629.
24. Zhu Y,. In Vivo RF Power and SAR Calibration for Multi-Port RF Transmission. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Honolulu, Hawaii; 2009. p 599.
25. Brunner DO, Pruessmann KP,. Optimal design of multiple-channel RF pulses under strict power and SAR constraints. Magn Reson Med 2010; 63: 1280-1291.
26. Graesslin IS, C. Annighoefer B,., Weller J,., Diederer S,., Brunner D,., Homann H,., Schweser F,., Katscher U,., Pruessmann K,., Boernert P,. Local SAR constrained Hotspot Reduction by Temporal Averaging. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Stockholm, Sweden; 2010. p 4932.
27. Graesslin I, Schweser F, Annighoefer B, Biederer S, Katscher U, Nehrke K, Stahl H, Dingemans H, Mens G, Bornert P,. A Minimum SAR RF Pulse Design Approach for Parallel Tx with Local Hot Spot Suppression and Exact Fidelity Constraint. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Toronto, Canada; 2008. p 621.
28. Cloos MA, Luong M, Ferrand G, Amadon A, Le Bihan D, Boulant N,. Local SAR reduction in parallel excitation based on channel-dependent Tikhonov parameters. J Magn Reson Imaging 2010; 32: 1209-1216.
29. Hoult DI, Phil D,. Sensitivity and power deposition in a high-field imaging experiment. J Magn Reson Imaging 2000; 12: 46-67.
30. Ibrahim TS, Lee R, Baertlein BA, Kangarlu A, Robitaille PL,. Application of finite difference time domain method for the design of birdcage RF head coils using multi-port excitations. Magn Reson Imaging 2000; 18: 733-742.
31. Ulloa JL, Irarrazaval P, Hajnal JV,. Exploring 3D RF Shimming for Slice Selective Imaging. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Miami Beach, Florida; 2005. p 21.
32. Saekho S, Yip CY, Noll DC, Boada FE, Stenger VA,. Fast-kz three-dimensional tailored radiofrequency pulse for reduced B1 inhomogeneity. Magn Reson Med 2006; 55: 719-724.
33. Pauly J, Nishimura D, Macovski A,. A K-space analysis of small-tip-angle excitation. J Magn Reson 1989; 81: 43-56.
34. Gebhardt M, Diehl D, Adalsteinsson E, Wald LL, Eichfelder G,. Evaluation of Maximum Local SAR for Parallel Transmission (PTx) Pulses Based on Pre-Calculated Field Data Using a Selected Subset of "Virtual Observation Points". In: Proceedings of the International Society for Magnetic Resonance in Medicine, Stockholm, Sweden; 2010. p 1441.
35. Eichfelder G, Gebhardt M,. Local specific absorption rate control for parallel transmission by virtual observation points. Magn Reson Med 2011.
36. Taflove A, Hagness SC,. Computational electrodynamics: the finite-difference time-domain method. Boston: Artech House; 2000. xxiii, 852 p.
37. Christ A, Kainz W, Hahn EG, Honegger K, Zefferer M, Neufeld E, Rascher W, Janka R, Bautz W, Chen J, Kiefer B, Schmitt P, Hollenbach HP, Shen JX, Oberle M, Szczerba D, Kam A, Guag JW, Kuster N,. The virtual family-development of surface-based anatomical models of two adults and two children for dosimetric simulations. Phys Med Biol 2010; 55: N23-N38.
38. IEEE Recommended Practice for Measurements and Computations of Radio Frequency Electromagnetic Fields With Respect to Human Exposure to Such Fields,100 kHz-300 GHz. IEEE Std C953-2002 (Revision of IEEE Std C953-1991) 2002; i-126.
39. Strang G,. Introduction to linear algebra. Wellesley, MA: Wellesley-Cambridge Press; 2009. ix, 574 p.
40. Zhan X,. Matrix inequalities. Berlin, New York: Springer; 2002. vi, 116 p.
41. Graesslin I, Weller J, Schweser F, Annighoefer B, Diederer S, Katscher U, Nielsen T, Harvey P, Boernert P,. SAR Hotspot Reduction by Temporal Averaging in Parallel Transmission. In: Proceedings of the International Society for Magnetic Resonance in Medicine, Honolulu, Hawaii; 2009. p 3037.