Design of internal MRI coils using ultimate intrinsic SNR

ObjectInternal MRI coils have important applications in diagnostic and interventional studies. Since they can be placed very close to the region of interest in the body, they are favored over external coils in applications where high-resolution images are required. In this paper it is demonstrated that ultimate intrinsic SNR (UISNR) and the optimum coil sensitivity solutions can be used to make new coil designs with higher intrinsic SNR.Materials and methodsIn this study, UISNR, which is the maximum attainable value of the intrinsic SNR, is used as a measure of performance and as a design criterion. As an example, a novel endorectal MRI coil is designed. The design is tested with phantom and patient studies.ResultsAn endorectal coil is built to demonstrate the effectiveness of the design strategy. ISNR of the endorectal coil approximates the UISNR to 72%.ConclusionAn internal coil design method that takes advantage of the UISNR and optimum coil sensitivity calculations was presented. This method can also be used to design better internal MRI coils for different applications.

[1]  E. Atalar,et al.  Evaluation of internal MRI coils using ultimate intrinsic SNR , 2004, Magnetic resonance in medicine.

[2]  W. Edelstein,et al.  The intrinsic signal‐to‐noise ratio in NMR imaging , 1986, Magnetic resonance in medicine.

[3]  J L Duerk,et al.  Intravascular (catheter) NMR receiver probe: Preliminary design analysis and application to canine iliofemoral imaging , 1992, Magnetic resonance in medicine.

[4]  Ogan Ocali,et al.  Intravascular magnetic resonance imaging using a loopless catheter antenna , 1997, Magnetic resonance in medicine.

[5]  D I Hoult,et al.  The signal-to-noise ratio of the nuclear magnetic resonance experiment. 1976. , 1976, Journal of magnetic resonance.

[6]  E. Atalar,et al.  Phased‐array MRI of canine prostate using endorectal and endourethral coils , 2003, Magnetic resonance in medicine.

[7]  D. Pozar Microwave Engineering , 1990 .

[8]  Alan C. Evans,et al.  A nonparametric method for automatic correction of intensity nonuniformity in MRI data , 1998, IEEE Transactions on Medical Imaging.

[9]  Charles R. Meyer,et al.  Retrospective correction of intensity inhomogeneities in MRI , 1995, IEEE Trans. Medical Imaging.

[10]  E Atalar,et al.  Endourethral MRI , 2001, Magnetic resonance in medicine.

[11]  R E Lenkinski,et al.  Prostate: MR imaging with an endorectal surface coil. , 1989, Radiology.

[12]  Ergin Atalar,et al.  Transesophageal magnetic resonance imaging , 1999, Magnetic resonance in medicine.

[13]  Gabor Fichtinger,et al.  Design of a novel MRI compatible manipulator for image guided prostate interventions , 2005, IEEE Transactions on Biomedical Engineering.

[14]  E. Atalar,et al.  Ultimate intrinsic signal‐to‐noise ratio in MRI , 1998, Magnetic resonance in medicine.