Phillip Zhe Sun

Summary

Affiliation: Harvard University
Country: USA

Publications

  1. pmc Magnetic resonance characterization of ischemic tissue metabolism
    Jerry S Cheung
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
    Open Neuroimag J 5:66-73. 2011
  2. pmc Evaluation of the dependence of CEST-EPI measurement on repetition time, RF irradiation duty cycle and imaging flip angle for enhanced pH sensitivity
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
    Phys Med Biol 58:N229-40. 2013
  3. pmc Developing a multiscale, multi-resolution agent-based brain tumor model by graphics processing units
    Le Zhang
    Department of Mathematical Sciences, Michigan Technological University, Houghton, MI 49931, USA
    Theor Biol Med Model 8:46. 2011
  4. pmc Imaging acute ischemic tissue acidosis with pH-sensitive endogenous amide proton transfer (APT) MRI--correction of tissue relaxation and concomitant RF irradiation effects toward mapping quantitative cerebral tissue pH
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
    Neuroimage 60:1-6. 2012
  5. pmc Simplified quantification of labile proton concentration-weighted chemical exchange rate (k(ws) ) with RF saturation time dependent ratiometric analysis (QUESTRA): normalization of relaxation and RF irradiation spillover effects for improved quantitative
    Phillip Zhe Sun
    Department of Radiology, Harvard Medical School, Charlestown, MA, USA
    Magn Reson Med 67:936-42. 2012
  6. pmc Investigation of optimizing and translating pH-sensitive pulsed-chemical exchange saturation transfer (CEST) imaging to a 3T clinical scanner
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Department of Radiology and Harvard Medical School, Charlestown, Massachusetts 02129, USA
    Magn Reson Med 60:834-41. 2008
  7. pmc Simultaneous determination of labile proton concentration and exchange rate utilizing optimal RF power: Radio frequency power (RFP) dependence of chemical exchange saturation transfer (CEST) MRI
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Rm 2301, 149 13th Street, Charlestown, MA 02129 2020, USA
    J Magn Reson 202:155-61. 2010
  8. pmc Fast multislice pH-weighted chemical exchange saturation transfer (CEST) MRI with Unevenly segmented RF irradiation
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
    Magn Reson Med 65:588-94. 2011
  9. pmc Early experience of translating pH-weighted MRI to image human subjects at 3 Tesla
    Phillip Zhe Sun
    Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Athinoula A Martinos Center for Biomedical Imaging, Charlestown, Mass 02129, USA
    Stroke 41:S147-51. 2010
  10. pmc Association between pH-weighted endogenous amide proton chemical exchange saturation transfer MRI and tissue lactic acidosis during acute ischemic stroke
    Phillip Zhe Sun
    Department of Radiology, Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
    J Cereb Blood Flow Metab 31:1743-50. 2011

Collaborators

Detail Information

Publications31

  1. pmc Magnetic resonance characterization of ischemic tissue metabolism
    Jerry S Cheung
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
    Open Neuroimag J 5:66-73. 2011
    ..Our current article provides a concise overview of stroke pathology, conventional and emerging imaging and spectroscopy techniques, and data analysis tools for characterizing ischemic tissue damage...
  2. pmc Evaluation of the dependence of CEST-EPI measurement on repetition time, RF irradiation duty cycle and imaging flip angle for enhanced pH sensitivity
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
    Phys Med Biol 58:N229-40. 2013
    ..The simulation results were validated using a dual-pH creatine-gel CEST phantom. In summary, our study provides a useful framework for optimizing CEST MRI experiments. ..
  3. pmc Developing a multiscale, multi-resolution agent-based brain tumor model by graphics processing units
    Le Zhang
    Department of Mathematical Sciences, Michigan Technological University, Houghton, MI 49931, USA
    Theor Biol Med Model 8:46. 2011
    ..Therefore, the new model has great potential for simulating and predicting real-time GBM progression, if real experimental data are incorporated...
  4. pmc Imaging acute ischemic tissue acidosis with pH-sensitive endogenous amide proton transfer (APT) MRI--correction of tissue relaxation and concomitant RF irradiation effects toward mapping quantitative cerebral tissue pH
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
    Neuroimage 60:1-6. 2012
    ..In summary, our study established an endogenous and quantitative pH imaging technique for improved characterization of ischemic tissue acidification and metabolism disruption...
  5. pmc Simplified quantification of labile proton concentration-weighted chemical exchange rate (k(ws) ) with RF saturation time dependent ratiometric analysis (QUESTRA): normalization of relaxation and RF irradiation spillover effects for improved quantitative
    Phillip Zhe Sun
    Department of Radiology, Harvard Medical School, Charlestown, MA, USA
    Magn Reson Med 67:936-42. 2012
    ..The proposed algorithm was confirmed numerically, and validated experimentally using a tissue-like phantom of serially titrated pH compartments...
  6. pmc Investigation of optimizing and translating pH-sensitive pulsed-chemical exchange saturation transfer (CEST) imaging to a 3T clinical scanner
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Department of Radiology and Harvard Medical School, Charlestown, Massachusetts 02129, USA
    Magn Reson Med 60:834-41. 2008
    ..9 ppm). Furthermore, pilot endogenous APT imaging of normal human volunteers was demonstrated, warranting future APT MRI of stroke patients to elucidate its diagnostic value...
  7. pmc Simultaneous determination of labile proton concentration and exchange rate utilizing optimal RF power: Radio frequency power (RFP) dependence of chemical exchange saturation transfer (CEST) MRI
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Rm 2301, 149 13th Street, Charlestown, MA 02129 2020, USA
    J Magn Reson 202:155-61. 2010
    ..The empirical solution was confirmed by numerical simulation, and experimental validation is needed to further evaluate the proposed technique...
  8. pmc Fast multislice pH-weighted chemical exchange saturation transfer (CEST) MRI with Unevenly segmented RF irradiation
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
    Magn Reson Med 65:588-94. 2011
    ..In sum, a fast multislice relaxation self-compensated CEST MRI sequence was developed, with significantly improved sensitivity and suitable for in vivo applications...
  9. pmc Early experience of translating pH-weighted MRI to image human subjects at 3 Tesla
    Phillip Zhe Sun
    Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Athinoula A Martinos Center for Biomedical Imaging, Charlestown, Mass 02129, USA
    Stroke 41:S147-51. 2010
    ..Tissue pH, a well-regulated physiological index that alters on disrupted tissue metabolism, may provide a surrogate metabolic imaging marker that augments the DWI and PWI for penumbra imaging...
  10. pmc Association between pH-weighted endogenous amide proton chemical exchange saturation transfer MRI and tissue lactic acidosis during acute ischemic stroke
    Phillip Zhe Sun
    Department of Radiology, Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
    J Cereb Blood Flow Metab 31:1743-50. 2011
    ....
  11. pmc Simulation and optimization of pulsed radio frequency irradiation scheme for chemical exchange saturation transfer (CEST) MRI-demonstration of pH-weighted pulsed-amide proton CEST MRI in an animal model of acute cerebral ischemia
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
    Magn Reson Med 66:1042-8. 2011
    ..In summary, our study elucidated the RF irradiation dependence of pulsed-CEST MRI contrast, providing useful insights to guide its experimental optimization and quantification...
  12. ncbi request reprint Imaging pH using the chemical exchange saturation transfer (CEST) MRI: Correction of concomitant RF irradiation effects to quantify CEST MRI for chemical exchange rate and pH
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Department of Radiology, Harvard Medical School, Charlestown, Massachusetts 02129, USA
    Magn Reson Med 60:390-7. 2008
    ....
  13. ncbi request reprint Relaxation-compensated fast multislice amide proton transfer (APT) imaging of acute ischemic stroke
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Department of Radiology and Harvard Medical School, 149 13th Street, Charlestown, MA 02129, USA
    Magn Reson Med 59:1175-82. 2008
    ..In summary, our study has established a fast volumetric pH-weighted APT imaging technique, allowing further investigation to fully evaluate its diagnostic power...
  14. pmc Simplified and scalable numerical solution for describing multi-pool chemical exchange saturation transfer (CEST) MRI contrast
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
    J Magn Reson 205:235-41. 2010
    ..In sum, our study established a simplified and scalable, yet reasonably accurate numerical solution, suitable for quantitatively describing multi-pool CEST contrast...
  15. pmc Improved diffusion measurement in heterogeneous systems using the magic asymmetric gradient stimulated echo (MAGSTE) technique
    Phillip Zhe Sun
    Russell H Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
    J Magn Reson 187:177-83. 2007
    ..In sum, this study showed that the MAGSTE technique provided diffusion measurements superior to those of the bPGSTE sequence, especially in the presence of severe heterogeneous background gradients...
  16. ncbi request reprint Correction for artifacts induced by B(0) and B(1) field inhomogeneities in pH-sensitive chemical exchange saturation transfer (CEST) imaging
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA
    Magn Reson Med 58:1207-15. 2007
    ..In addition, the proposed algorithm was verified with both numerical simulation and experimental measurements, and showed nearly complete correction of CEST imaging measurement errors caused by moderate field inhomogeneity...
  17. ncbi request reprint Simplified quantitative description of amide proton transfer (APT) imaging during acute ischemia
    Phillip Zhe Sun
    Russell H Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
    Magn Reson Med 57:405-10. 2007
    ..The results showed an optimal RF strength of 0.75 microT for our particular coil setup, and a maximally obtainable APT ratio difference of 2.9%+/-0.3% between ischemic and normal brain regions...
  18. pmc Fast radio-frequency enforced steady state (FRESS) spin echo MRI for quantitative T2 mapping: minimizing the apparent repetition time (TR) dependence for fast T2 measurement
    Jerry S Cheung
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
    NMR Biomed 25:189-94. 2012
    ..In summary, FRESS-SE T(2) MRI technique was developed for fast and accurate T(2) imaging, suitable for in vivo applications...
  19. ncbi request reprint Suppression of lipid artifacts in amide proton transfer imaging
    Phillip Zhe Sun
    Division of MRI Research, Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 2195, USA
    Magn Reson Med 54:222-5. 2005
    ..It is demonstrated that a chemical-shift-selective refocusing pulse in combination with crusher gradients can suppress this artifact and provide high-quality images...
  20. pmc Simultaneous experimental determination of labile proton fraction ratio and exchange rate with irradiation radio frequency power-dependent quantitative CEST MRI analysis
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
    Contrast Media Mol Imaging 8:246-51. 2013
    ..In summary, our study demonstrated quantitative DIACEST MRI, which remains promising to augment the conventional CEST-weighted MRI analysis...
  21. pmc Amide proton transfer imaging of 9L gliosarcoma and human glioblastoma xenografts
    Amandeep Salhotra
    Division of MR Research, Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
    NMR Biomed 21:489-97. 2008
    ..42%) for the human glioblastoma xenografts that contained hypocellular zones of necrosis. The preliminary results show that the APT technique at the protein level may provide a unique MRI contrast for the characterization of brain tumors...
  22. ncbi request reprint Detection of the ischemic penumbra using pH-weighted MRI
    Phillip Zhe Sun
    Division of MRI Research, Neurosection, Russell H Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
    J Cereb Blood Flow Metab 27:1129-36. 2007
    ..These first results show that pHWI can provide information complementary to PWI and DWI in the delineation of ischemic tissue...
  23. pmc Stratification of heterogeneous diffusion MRI ischemic lesion with kurtosis imaging: evaluation of mean diffusion and kurtosis MRI mismatch in an animal model of transient focal ischemia
    Jerry S Cheung
    Athinoula A Martinos Center, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
    Stroke 43:2252-4. 2012
    ..Our study examined the spatiotemporal characteristics of diffusion kurtosis imaging in an animal model of transient middle cerebral artery occlusion...
  24. ncbi request reprint MRI of insulitis in autoimmune diabetes
    Anna Moore
    Center for Molecular Imaging Research, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
    Magn Reson Med 47:751-8. 2002
    ..The results from this study could potentially lead to detection of immune infiltration during diabetes formation in vivo, which would be one of the earliest parameters of disease development...
  25. pmc Quantitative chemical exchange saturation transfer (qCEST) MRI--RF spillover effect-corrected omega plot for simultaneous determination of labile proton fraction ratio and exchange rate
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, 02129, USA
    Contrast Media Mol Imaging 9:268-75. 2014
    ..01), with little difference in their exchange rate (p = 0.32). In summary, our study extends the conventional omega plot for quantitative analysis of DIACEST MRI...
  26. ncbi request reprint Optimization of the irradiation power in chemical exchange dependent saturation transfer experiments
    Phillip Zhe Sun
    Division of MRI Research, Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
    J Magn Reson 175:193-200. 2005
    ..The results are confirmed experimentally on 4.7 T using a poly-L-lysine solution. The theory provides a useful tool for optimizing the irradiation power of the PT sequences in the presence of direct saturation effects...
  27. ncbi request reprint Quantification of iopamidol multi-site chemical exchange properties for ratiometric chemical exchange saturation transfer (CEST) imaging of pH
    Phillip Zhe Sun
    Department of Radiology, Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
    Phys Med Biol 59:4493-504. 2014
    ..2*10(pH-4.1)) and amide (ksw = 1.2*10(pH-4.6)) protons that are statistically different from each other (P < 0.01, ANCOVA), understanding of which should help guide in vivo translation of iopamidol pH imaging. ..
  28. pmc Sensitivity-enhanced chemical exchange saturation transfer (CEST) MRI with least squares optimization of Carr Purcell Meiboom Gill multi-echo echo planar imaging
    Phillip Zhe Sun
    Athinoula A Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School
    Contrast Media Mol Imaging 9:177-81. 2014
    ..In summary, our results demonstrated CESTme EPI for sensitivity-enhanced CEST imaging...
  29. ncbi request reprint Analysis of the magic asymmetric gradient stimulated echo sequence with shaped gradients
    Phillip Zhe Sun
    F M Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD 21205, USA
    J Magn Reson 171:324-9. 2004
    ..The derivation enables the MAGSTE sequence to be implemented on systems with non-negligible gradient rise times...
  30. ncbi request reprint Quantitative description of proton exchange processes between water and endogenous and exogenous agents for WEX, CEST, and APT experiments
    Jinyuan Zhou
    Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205 2195, USA
    Magn Reson Med 51:945-52. 2004
    ..As an example, the case of endogenous amide proton exchange in the rat brain at 4.7 T is analyzed in detail...
  31. ncbi request reprint Background gradient suppression in pulsed gradient stimulated echo measurements
    Phillip Zhe Sun
    Division of Health Sciences and Technology, Harvard University MIT, 77 Massachusetts Avenue, E25 519, Cambridge, MA 02139, USA
    J Magn Reson 161:168-73. 2003
    ..Since the coding intervals are typically at least an order of magnitude shorter than the storage time, this new method succeeds in suppressing cross-terms for a much wider range of heterogeneous samples...