Measurements of T1‐relaxation in ex vivo prostate tissue at 132 μT

The proton T1 was measured at 132 μT in ex vivo prostate tissue specimens from radical prostatectomies of 35 patients with prostate cancer. Each patient provided two specimens. The NMR and MRI measurements involved proton repolarization, a field of typically 150 mT and detection of the 5.6‐kHz signal with a superconducting quantum interference device. Values of T1 varied from 41 to 86 ms. Subsequently, the percentages of tissue types were determined histologically. The theoretical image contrast is quantified for each case by δ = [1 – T1(more cancer)/T1(less cancer)]. A linear fit of δ versus difference in percentage cancer yields T1 (100% cancer)/T1 (0% cancer) = 0.70 ± 0.05 with correlation coefficient R2 = 0.30. Two‐dimensional T1 maps for four specimens demonstrate variation within a single specimen. These results suggest that MR images with T1 contrast established at ultra‐low fields may discriminate prostate cancer from normal prostate tissue in vivo without a contrast agent. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.

[1]  John Clarke,et al.  SQUID-detected magnetic resonance imaging in microtesla fields. , 2007, Annual review of biomedical engineering.

[2]  Seymour H. Koenig,et al.  Field-cycling relaxometry of protein solutions and tissue: Implications for MRI , 1990 .

[3]  J. Clarke,et al.  SQUID-Detected Magnetic Resonance Imaging in Microtesla Magnetic Fields , 2004 .

[4]  D. Gleason,et al.  Histologic Grading and Staging of Prostatic Carcinoma , 1981 .

[5]  Martin Burghoff,et al.  Nuclear magnetic resonance in the earth’s magnetic field using a nitrogen-cooled superconducting quantum interference device , 2007 .

[6]  J. Hutchison,et al.  Liquid helium cryostat for SQUID-based MRI receivers , 2005 .

[7]  A. Villers,et al.  Dynamic contrast enhanced, pelvic phased array magnetic resonance imaging of localized prostate cancer for predicting tumor volume: correlation with radical prostatectomy findings. , 2006, The Journal of urology.

[8]  Robert McDermott,et al.  Microtesla MRI with a superconducting quantum interference device. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[9]  John Clarke,et al.  SQUID‐detected MRI at 132 μT with T1‐weighted contrast established at 10 μT–300 mT , 2005 .

[10]  Robert McDermott,et al.  Microtesla magnetic resonance imaging with a superconducting quantum interference device , 2004 .

[11]  Clare Allen,et al.  How good is MRI at detecting and characterising cancer within the prostate? , 2006, European urology.

[12]  Robert H Kraus,et al.  Microtesla MRI of the human brain combined with MEG. , 2008, Journal of magnetic resonance.

[13]  P. Carroll,et al.  Prostate cancer: localization with three-dimensional proton MR spectroscopic imaging--clinicopathologic study. , 1999, Radiology.

[14]  J. Kurhanewicz,et al.  Combined magnetic resonance imaging and spectroscopic imaging approach to molecular imaging of prostate cancer , 2002, Journal of magnetic resonance imaging : JMRI.

[15]  Klaas Nicolay,et al.  MRI contrast agents: current status and future perspectives. , 2007, Anti-cancer agents in medicinal chemistry.

[16]  R Alagappan,et al.  Detection of extracapsular extension of prostate carcinoma with endorectal and phased-array coil MR imaging: multivariate feature analysis. , 1997, Radiology.

[17]  P. Carroll,et al.  Carcinoma of the prostate gland: MR imaging with pelvic phased-array coils versus integrated endorectal--pelvic phased-array coils. , 1994, Radiology.

[18]  Michael Hatridge,et al.  SQUID-detected microtesla MRI in the presence of metal. , 2006, Journal of magnetic resonance.

[19]  M. Hatridge,et al.  SQUID-detected in vivo MRI at microtesla magnetic fields , 2005, IEEE Transactions on Applied Superconductivity.

[20]  J Kurhanewicz,et al.  Sextant localization of prostate cancer: comparison of sextant biopsy, magnetic resonance imaging and magnetic resonance spectroscopic imaging with step section histology. , 2000, The Journal of urology.

[21]  Thomas Hambrock,et al.  Prostate cancer: multiparametric MR imaging for detection, localization, and staging. , 2011, Radiology.

[22]  Martin Burghoff,et al.  J-coupling nuclear magnetic resonance spectroscopy of liquids in nT fields. , 2006, Journal of the American Chemical Society.

[23]  Albert Macovski,et al.  Prepolarized magnetic resonance imaging around metal orthopedic implants , 2006, Magnetic resonance in medicine.

[24]  S. H. Koenig,et al.  Relaxometry of Tissue , 2007 .

[25]  H. Huisman,et al.  Prostate cancer localization with dynamic contrast-enhanced MR imaging and proton MR spectroscopic imaging. , 2006, Radiology.

[26]  Robert McDermott,et al.  Liquid-State NMR and Scalar Couplings in Microtesla Magnetic Fields , 2002, Science.