Howard Halpern

Research Summary
Howard J. Halpern, MD, PhD, specializes in medical imaging techniques. He is an expert in very low frequency-imaging-electron paramagnetic resonance (VLF-I-EPR). This technique enables measurement of changes in oxygen content in tumor tissues--a key determinant of response to radiation therapy. Dr. Halpern is the co-author of a textbook on free radical biology. He serves as the principal investigator for the Oversight Committee for the Laboratory Training of Radiation Oncology Residents.
  • University of Wisconsin, Madison, Wisconsin, PhD High Energy Physics 06/1976
  • University of Miami, Miami, Florida, MD Medicine 061980
Biosciences Graduate Program Association
  1. Gertsenshteyn I, Epel B, Ahluwalia A, Kim H, Fan X, Barth E, Zamora M, Markiewicz E, Tsai HM, Sundramoorthy S, Leoni L, Lukens J, Bhuiyan M, Freifelder R, Kucharski A, Giurcanu M, Roman BB, Karczmar G, Kao CM, Halpern H, Chen CT. The optimal 18F-fluoromisonidazole PET threshold to define tumor hypoxia in preclinical squamous cell carcinomas using pO2 electron paramagnetic resonance imaging as reference truth. Eur J Nucl Med Mol Imaging. 2022 Jul 06. View in: PubMed

  2. Bader KB, Wallach EL, Shekhar H, Flores-Guzman F, Halpern HJ, Hernandez SL. Estimating the mechanical energy of histotripsy bubble clouds with high frame rate imaging. Phys Med Biol. 2021 08 05; 66(16). View in: PubMed

  3. Qiao Z, Redler G, Epel B, Halpern H. A balanced total-variation-Chambolle-Pock algorithm for EPR imaging. J Magn Reson. 2021 07; 328:107009. View in: PubMed

  4. Kim H, Epel B, Sundramoorthy S, Tsai HM, Barth E, Gertsenshteyn I, Halpern H, Hua Y, Xie Q, Chen CT, Kao CM. Development of a PET/EPRI combined imaging system for assessing tumor hypoxia. J Instrum. 2021 Mar; 16(3). View in: PubMed

  5. Gertsenshteyn I, Epel B, Barth E, Leoni L, Markiewicz E, Tsai HM, Fan X, Giurcanu M, Bodero D, Zamora M, Sundramoorthy S, Kim H, Freifelder R, Bhuiyan M, Kucharski A, Karczmar G, Kao CM, Halpern H, Chen CT. Improving Tumor Hypoxia Location in 18F-Misonidazole PET with Dynamic Contrast-enhanced MRI Using Quantitative Electron Paramagnetic Resonance Partial Oxygen Pressure Images. Radiol Imaging Cancer. 2021 03; 3(2):e200104. View in: PubMed

  6. Halpern HJ, Epel BM. Going Low in a World Going High: The Physiologic Use of Lower Frequency Electron Paramagnetic Resonance. Appl Magn Reson. 2020 Oct; 51(9-10):887-907. View in: PubMed

  7. Redler G, Pearson E, Liu X, Gertsenshteyn I, Epel B, Pelizzari C, Aydogan B, Weichselbaum R, Halpern HJ, Wiersma RD. Small Animal IMRT Using 3D-Printed Compensators. Int J Radiat Oncol Biol Phys. 2021 06 01; 110(2):551-565. View in: PubMed

  8. Swartz HM, Flood AB, Schaner PE, Halpern H, Williams BB, Pogue BW, Gallez B, Vaupel P. How best to interpret measures of levels of oxygen in tissues to make them effective clinical tools for care of patients with cancer and other oxygen-dependent pathologies. Physiol Rep. 2020 08; 8(15):e14541. View in: PubMed

  9. Gertsenshteyn I, Giurcanu M, Vaupel P, Halpern H. Biological validation of electron paramagnetic resonance (EPR) image oxygen thresholds in tissue. J Physiol. 2021 03; 599(6):1759-1767. View in: PubMed

  10. Waller J, Onderdonk B, Flood A, Swartz H, Shah J, Shah A, Aydogan B, Halpern H, Hasan Y. The clinical utility of imaging methods used to measure hypoxia in cervical cancer. Br J Radiol. 2020 Jul; 93(1111):20190640. View in: PubMed

  11. Gonet M, Epel B, Halpern HJ, Elas M. Merging Preclinical EPR Tomography with other Imaging Techniques. Cell Biochem Biophys. 2019 Sep; 77(3):187-196. View in: PubMed

  12. Chen NT, Barth ED, Lee TH, Chen CT, Epel B, Halpern HJ, Lo LW. Highly sensitive electron paramagnetic resonance nanoradicals for quantitative intracellular tumor oxymetric images. Int J Nanomedicine. 2019; 14:2963-2971. View in: PubMed

  13. Bodo S, Campagne C, Thin TH, Higginson DS, Vargas HA, Hua G, Fuller JD, Ackerstaff E, Russell J, Zhang Z, Klingler S, Cho H, Kaag MG, Mazaheri Y, Rimner A, Manova-Todorova K, Epel B, Zatcky J, Cleary CR, Rao SS, Yamada Y, Zelefsky MJ, Halpern HJ, Koutcher JA, Cordon-Cardo C, Greco C, Haimovitz-Friedman A, Sala E, Powell SN, Kolesnick R, Fuks Z. Single-dose radiotherapy disables tumor cell homologous recombination via ischemia/reperfusion injury. J Clin Invest. 2019 02 01; 129(2):786-801. View in: PubMed

  14. Epel B, Maggio MC, Barth ED, Miller RC, Pelizzari CA, Krzykawska-Serda M, Sundramoorthy SV, Aydogan B, Weichselbaum RR, Tormyshev VM, Halpern HJ. Oxygen-Guided Radiation Therapy. Int J Radiat Oncol Biol Phys. 2019 03 15; 103(4):977-984. View in: PubMed

  15. Qiao Z, Zhang Z, Pan X, Epel B, Redler G, Xia D, Halpern H. Optimization-based image reconstruction from sparsely sampled data in electron paramagnetic resonance imaging. J Magn Reson. 2018 09; 294:24-34. View in: PubMed

  16. Boris E, Sundramoorthy SV, Halpern HJ. 250 MHz passive Q-modulator for reflection resonators. Concepts Magn Reson Part B Magn Reson Eng. 2017 Apr; 47B(2). View in: PubMed

  17. Qiao Z, Redler G, Qian Y, Tang S, Epel B, Halpern H. Investigation of the preconditioner-parameter in the preconditioned Chambolle-Pock algorithm applied to optimization-based image reconstruction. J Xray Sci Technol. 2018; 26(3):435-448. View in: PubMed

  18. Rinard GA, Quine RW, Buchanan LA, Eaton SS, Eaton GR, Epel B, Sundramoorthy SV, Halpern HJ. Resonators for In Vivo Imaging: Practical Experience. Appl Magn Reson. 2017 Dec; 48(11-12):1227-1247. View in: PubMed

  19. Sundramoorthy SV, Epel B, Halpern HJ. A Pulse EPR 25 mT magnetometer with 10ppm resolution. Appl Magn Reson. 2017 Aug; 48(8):805-811. View in: PubMed

  20. Qiao Z, Redler G, Gui Z, Qian Y, Epel B, Halpern H. Three novel accurate pixel-driven projection methods for 2D CT and 3D EPR imaging. J Xray Sci Technol. 2018; 26(1):83-102. View in: PubMed

  21. Epel B, Krzykawska-Serda M, Tormyshev V, Maggio MC, Barth ED, Pelizzari CA, Halpern HJ. Spin Lattice Relaxation EPR pO2 Images May Direct the Location of Radiation Tumor Boosts to Enhance Tumor Cure. Cell Biochem Biophys. 2017 Dec; 75(3-4):295-298. View in: PubMed

  22. Kotecha M, Epel B, Ravindran S, Dorcemus D, Nukavarapu S, Halpern H. Noninvasive Absolute Electron Paramagnetic Resonance Oxygen Imaging for the Assessment of Tissue Graft Oxygenation. Tissue Eng Part C Methods. 2018 01; 24(1):14-19. View in: PubMed

  23. Rahimi R, Halpern HJ, Takui T. In Vivo EPR Resolution Enhancement Using Techniques Known from Quantum Computing Spin Technology. Adv Exp Med Biol. 2017; 977:335-339. View in: PubMed

  24. Shi Y, Quine RW, Rinard GA, Buchanan L, Eaton SS, Eaton GR, Epel B, Seagle SW, Halpern HJ. Triarylmethyl Radical OX063d24 Oximetry: Electron Spin Relaxation at 250 MHz and RF Frequency Dependence of Relaxation and Signal-to-Noise. Adv Exp Med Biol. 2017; 977:327-334. View in: PubMed

  25. Krzykawska-Serda M, Miller RC, Elas M, Epel B, Barth ED, Maggio M, Halpern HJ. Correlation Between Hypoxia Proteins and EPR-Detected Hypoxia in Tumors. Adv Exp Med Biol. 2017; 977:319-325. View in: PubMed

  26. Epel B, Maggio M, Pelizzari C, Halpern HJ. Electron Paramagnetic Resonance pO2 Image Tumor Oxygen-Guided Radiation Therapy Optimization. Adv Exp Med Biol. 2017; 977:287-296. View in: PubMed

  27. Eaton SS, Shi Y, Woodcock L, Buchanan LA, McPeak J, Quine RW, Rinard GA, Epel B, Halpern HJ, Eaton GR. Rapid-scan EPR imaging. J Magn Reson. 2017 07; 280:140-148. View in: PubMed

  28. Epel B, Kotecha M, Halpern HJ. In vivo preclinical cancer and tissue engineering applications of absolute oxygen imaging using pulse EPR. J Magn Reson. 2017 07; 280:149-157. View in: PubMed

  29. Epel B, Haney CR, Hleihel D, Wardrip C, Barth ED, Halpern HJ. Electron paramagnetic resonance oxygen imaging of a rabbit tumor using localized spin probe delivery. Med Phys. 2010 Jun; 37(6Part1):2553-2559. View in: PubMed

  30. Shi Y, Quine RW, Rinard GA, Buchanan L, Eaton SS, Eaton GR, Epel B, Seagle SW, Halpern HJ. Triarylmethyl Radical: EPR Signal to Noise at Frequencies between 250 MHz and 1.5 GHz and Dependence of Relaxation on Radical and Salt Concentration and on Frequency. Z Phys Chem (N F). 2017 04; 231(4):923-937. View in: PubMed

  31. Epel B, Sundramoorthy SV, Krzykawska-Serda M, Maggio MC, Tseytlin M, Eaton GR, Eaton SS, Rosen GM, Kao JPY, Halpern HJ. Imaging thiol redox status in murine tumors in vivo with rapid-scan electron paramagnetic resonance. J Magn Reson. 2017 Mar; 276:31-36. View in: PubMed

  32. Serda M, Wu YK, Barth ED, Halpern HJ, Rawal VH. EPR Imaging Spin Probe Trityl Radical OX063: A Method for Its Isolation from Animal Effluent, Redox Chemistry of Its Quinone Methide Oxidation Product, and in Vivo Application in a Mouse. Chem Res Toxicol. 2016 12 19; 29(12):2153-2156. View in: PubMed

  33. Tseytlin M, Epel B, Sundramoorthy S, Tipikin D, Halpern HJ. Decoupling of excitation and receive coils in pulsed magnetic resonance using sinusoidal magnetic field modulation. J Magn Reson. 2016 11; 272:91-99. View in: PubMed

  34. Christodoulou AG, Redler G, Clifford B, Liang ZP, Halpern HJ, Epel B. Fast dynamic electron paramagnetic resonance (EPR) oxygen imaging using low-rank tensors. J Magn Reson. 2016 09; 270:176-182. View in: PubMed

  35. Yang Z, Bridges MD, López CJ, Rogozhnikova OY, Trukhin DV, Brooks EK, Tormyshev V, Halpern HJ, Hubbell WL. A triarylmethyl spin label for long-range distance measurement at physiological temperatures using T1 relaxation enhancement. J Magn Reson. 2016 08; 269:50-54. View in: PubMed

  36. Epel B, Redler G, Tormyshev V, Halpern HJ. Towards Human Oxygen Images with Electron Paramagnetic Resonance Imaging. Adv Exp Med Biol. 2016; 876:363-369. View in: PubMed

  37. Epel B, Redler G, Pelizzari C, Tormyshev VM, Halpern HJ. Approaching Oxygen-Guided Intensity-Modulated Radiation Therapy. Adv Exp Med Biol. 2016; 876:185-193. View in: PubMed

  38. Epel B, Halpern HJ. In Vivo pO2 Imaging of Tumors: Oxymetry with Very Low-Frequency Electron Paramagnetic Resonance. Methods Enzymol. 2015; 564:501-27. View in: PubMed

  39. Qiao Z, Redler G, Epel B, Qian Y, Halpern H. Implementation of GPU-accelerated back projection for EPR imaging. J Xray Sci Technol. 2015; 23(4):423-33. View in: PubMed

  40. Qiao Z, Redler G, Epel B, Qian Y, Halpern H. 3D pulse EPR imaging from sparse-view projections via constrained, total variation minimization. J Magn Reson. 2015 Sep; 258:49-57. View in: PubMed

  41. Redler G, Epel B, Halpern HJ. Maximally spaced projection sequencing in electron paramagnetic resonance imaging. Concepts Magn Reson Part B Magn Reson Eng. 2015 Feb; 45(1):33-45. View in: PubMed

  42. Redler G, Qiao Z, Epel B, Halpern HJ. Real-Time Image Reconstruction for Pulse EPR Oxygen Imaging Using a GPU and Lookup Table Parameter Fitting. Concepts Magn Reson Part B Magn Reson Eng. 2015 Feb; 45(1):46-57. View in: PubMed

  43. Ahn KH, Manger R, Halpern HJ, Aydogan B. Increased dose near the skin due to electromagnetic surface beacon transponder. J Appl Clin Med Phys. 2015 May 08; 16(3):4930. View in: PubMed

  44. Epel B, Halpern HJ. Comparison of pulse sequences for R1-based electron paramagnetic resonance oxygen imaging. J Magn Reson. 2015 May; 254:56-61. View in: PubMed

  45. Qiao Z, Redler G, Halpern H. A simplified Katsevich algorithm motivated by the distribution properties of k-lines. J Electron Imaging. 2013 Oct 02; 22(4):043002. View in: PubMed

  46. Majumdar S, Kotecha M, Triplett W, Epel B, Halpern H. A DTI study to probe tumor microstructure and its connection with hypoxia. Annu Int Conf IEEE Eng Med Biol Soc. 2014; 2014:738-41. View in: PubMed

  47. Qiao Z, Redler G, Epel B, Halpern HJ. Comparison of parabolic filtration methods for 3D filtered back projection in pulsed EPR imaging. J Magn Reson. 2014 Nov; 248:42-53. View in: PubMed

  48. Tormyshev VM, Rogozhnikova OY, Bowman MK, Trukhin DV, Troitskaya TI, Vasiliev VG, Shundrin LA, Halpern HJ. Preparation of Diversely Substituted Triarylmethyl Radicals by the Quenching of Tris(2,3,5,6-tetrathiaaryl)methyl Cations with C-, N-, P-, and S-Nucleophiles. European J Org Chem. 2014 Jan 01; 2014(2):371-380. View in: PubMed

  49. Rogozhnikova OY, Vasiliev VG, Troitskaya TI, Trukhin DV, Mikhalina TV, Halpern HJ, Tormyshev VM. Generation of Trityl Radicals by Nucleophilic Quenching of Tris(2,3,5,6-tetrathiaaryl)methyl Cations and Practical and Convenient Large-Scale Synthesis of Persistent Tris(4-carboxy-2,3,5,6-tetrathiaaryl)methyl Radical. European J Org Chem. 2013 Jun 01; 2013(16):3347-3355. View in: PubMed

  50. Redler G, Epel B, Halpern HJ. EPR image based oxygen movies for transient hypoxia. Adv Exp Med Biol. 2014; 812:127-133. View in: PubMed

  51. Redler G, Epel B, Halpern HJ. What we learn from in vivo EPR oxygen images. Adv Exp Med Biol. 2014; 812:121-126. View in: PubMed

  52. Epel B, Redler G, Halpern HJ. How in vivo EPR measures and images oxygen. Adv Exp Med Biol. 2014; 812:113-119. View in: PubMed

  53. Sundramoorthy SV, Epel B, Halpern HJ. Orthogonal resonators for pulse in vivo electron paramagnetic imaging at 250 MHz. J Magn Reson. 2014 Mar; 240:45-51. View in: PubMed

  54. Tormyshev VM, Genaev AM, Sal'nikov GE, Rogozhnikova OY, Troitskaya TI, Trukhin DV, Mamatyuk VI, Fadeev DS, Halpern HJ. Triarylmethanols bearing bulky aryl groups and the NOESY/EXSY experimental observation of two-ring-flip mechanism for helicity reversal of molecular propellers. European J Org Chem. 2012 Jan; 2012(3). View in: PubMed

  55. Barrett HH, Kupinski MA, Müeller S, Halpern HJ, Morris JC, Dwyer R. Objective assessment of image quality VI: imaging in radiation therapy. Phys Med Biol. 2013 Nov 21; 58(22):8197-213. View in: PubMed

  56. Liu GF, Ranck MC, Solanki AA, Cao H, Kolokythas A, Wenig BL, Chen L, Ard S, Weichselbaum RR, Halpern H, Spiotto MT. Racial parities in outcomes after radiotherapy for head and neck cancer. Cancer. 2014 Jan 15; 120(2):244-52. View in: PubMed

  57. Epel B, Bowman MK, Mailer C, Halpern HJ. Absolute oxygen R1e imaging in vivo with pulse electron paramagnetic resonance. Magn Reson Med. 2014 Aug; 72(2):362-8. View in: PubMed

  58. Elas M, Magwood JM, Butler B, Li C, Wardak R, DeVries R, Barth ED, Epel B, Rubinstein S, Pelizzari CA, Weichselbaum RR, Halpern HJ. EPR oxygen images predict tumor control by a 50% tumor control radiation dose. Cancer Res. 2013 Sep 01; 73(17):5328-35. View in: PubMed

  59. Redler G, Elas M, Epel B, Barth ED, Halpern HJ. Radiation oxygen biology with pulse electron paramagnetic resonance imaging in animal tumors. Adv Exp Med Biol. 2013; 789:399-404. View in: PubMed

  60. Redler G, Barth ED, Bauer KS, Kao JP, Rosen GM, Halpern HJ. In vivo electron paramagnetic resonance imaging of differential tumor targeting using cis-3,4-di(acetoxymethoxycarbonyl)-2,2,5,5-tetramethyl-1-pyrrolidinyloxyl. Magn Reson Med. 2014 Apr; 71(4):1650-6. View in: PubMed

  61. Redler G, Epel B, Halpern HJ. Principal component analysis enhances SNR for dynamic electron paramagnetic resonance oxygen imaging of cycling hypoxia in vivo. Magn Reson Med. 2014 Jan; 71(1):440-50. View in: PubMed

  62. Elas M, Ichikawa K, Halpern HJ. Oxidative stress imaging in live animals with techniques based on electron paramagnetic resonance. Radiat Res. 2012 Apr; 177(4):514-23. View in: PubMed

  63. Shin CS, Dunnam CR, Borbat PP, Dzikovski B, Barth ED, Halpern HJ, Freed JH. ESR Microscopy for Biological and Biomedical Applications. Nanosci Nanotechnol Lett. 2011 Aug; 3(4):561-567. View in: PubMed

  64. Seifi P, Epel B, Sundramoorthy SV, Mailer C, Halpern HJ. Frequency bandwidth extension by use of multiple Zeeman field offsets for electron spin-echo EPR oxygen imaging of large objects. Med Phys. 2011 Jun; 38(6):3062-8. View in: PubMed

  65. Epel B, Sundramoorthy SV, Barth ED, Mailer C, Halpern HJ. Comparison of 250 MHz electron spin echo and continuous wave oxygen EPR imaging methods for in vivo applications. Med Phys. 2011 Apr; 38(4):2045-52. View in: PubMed

  66. Tseitlin M, Quine RW, Eaton SS, Eaton GR, Halpern HJ, Ardenkjaer-Larsen JH. Use of the Frank sequence in pulsed EPR. J Magn Reson. 2011 Apr; 209(2):306-9. View in: PubMed

  67. Seifi P, Epel B, Mailer C, Halpern HJ. Multiple-stepped Zeeman field offset method applied in acquiring enhanced resolution spin-echo electron paramagnetic resonance images. Med Phys. 2010 Oct; 37(10):5412-20. View in: PubMed

  68. Elas M, Hleihel D, Barth ED, Haney CR, Ahn KH, Pelizzari CA, Epel B, Weichselbaum RR, Halpern HJ. Where it's at really matters: in situ in vivo vascular endothelial growth factor spatially correlates with electron paramagnetic resonance pO2 images in tumors of living mice. Mol Imaging Biol. 2011 Dec; 13(6):1107-13. View in: PubMed

  69. Haney CR, Fan X, Parasca AD, Karczmar GS, Halpern HJ, Pelizzari CA. Immobilization Using Dental Material Casts Facilitates Accurate Serial and Multimodality Small Animal Imaging. Concepts Magn Reson Part B Magn Reson Eng. 2008 Apr; 33B(2):138-144. View in: PubMed

  70. Epel B, Haney CR, Hleihel D, Wardrip C, Barth ED, Halpern HJ. Electron paramagnetic resonance oxygen imaging of a rabbit tumor using localized spin probe delivery. Med Phys. 2010 Jun; 37(6):2553-9. View in: PubMed

  71. Burks SR, Macedo LF, Barth ED, Tkaczuk KH, Martin SS, Rosen GM, Halpern HJ, Brodie AM, Kao JP. Anti-HER2 immunoliposomes for selective delivery of electron paramagnetic resonance imaging probes to HER2-overexpressing breast tumor cells. Breast Cancer Res Treat. 2010 Nov; 124(1):121-31. View in: PubMed

  72. Subramanian VS, Epel B, Mailer C, Halpern HJ. A passive dual-circulator based transmit/receive switch for use with reflection resonators in pulse EPR. Concepts Magn Reson Part B Magn Reson Eng. 2009 Aug; 35B(3):133-138. View in: PubMed

  73. Epel B, Sundramoorthy SV, Mailer C, Halpern HJ. A Versatile High Speed 250 MHz Pulse Imager for Biomedical Applications. Concepts Magn Reson Part B Magn Reson Eng. 2008 Jul 10; 33B(3):163-176. View in: PubMed

  74. Burks SR, Barth ED, Halpern HJ, Rosen GM, Kao JP. Cellular uptake of electron paramagnetic resonance imaging probes through endocytosis of liposomes. Biochim Biophys Acta. 2009 Oct; 1788(10):2301-8. View in: PubMed

  75. Cage B, McNeely JH, Russek SE, Halpern HJ. Thermomagnetic properties of the Finland trityl radical. J Appl Phys. 2009 Feb 15; 105(4):43905. View in: PubMed

  76. Haney CR, Parasca AD, Fan X, Bell RM, Zamora MA, Karczmar GS, Mauceri HJ, Halpern HJ, Weichselbaum RR, Pelizzari CA. Characterization of response to radiation mediated gene therapy by means of multimodality imaging. Magn Reson Med. 2009 Aug; 62(2):348-56. View in: PubMed

  77. Elas M, Bell R, Hleihel D, Barth ED, McFaul C, Haney CR, Bielanska J, Pustelny K, Ahn KH, Pelizzari CA, Kocherginsky M, Halpern HJ. Electron paramagnetic resonance oxygen image hypoxic fraction plus radiation dose strongly correlates with tumor cure in FSa fibrosarcomas. Int J Radiat Oncol Biol Phys. 2008 Jun 01; 71(2):542-9. View in: PubMed

  78. Ahn KH, Subramanian VS, Halpern HJ. Scaling of EPR spectral-spatial images with size of sample: images of a sample greater than 5 cm in linear dimension. Med Phys. 2007 Dec; 34(12):4854-9. View in: PubMed

  79. Kao JP, Barth ED, Burks SR, Smithback P, Mailer C, Ahn KH, Halpern HJ, Rosen GM. Very-low-frequency electron paramagnetic resonance (EPR) imaging of nitroxide-loaded cells. Magn Reson Med. 2007 Oct; 58(4):850-4. View in: PubMed

  80. Pan X, Xia D, Halpern H. Targeted-ROI imaging in electron paramagnetic resonance imaging. J Magn Reson. 2007 Jul; 187(1):66-77. View in: PubMed

  81. Ahn KH, Halpern HJ. Comparison of local and global angular interpolation applied to spectral-spatial EPR image reconstruction. Med Phys. 2007 Mar; 34(3):1047-52. View in: PubMed

  82. Ahn KH, Halpern HJ. Simulation of 4D spectral-spatial EPR images. J Magn Reson. 2007 Jul; 187(1):1-9. View in: PubMed

  83. Ahn KH, Halpern HJ. Object dependent sweep width reduction with spectral-spatial EPR imaging. J Magn Reson. 2007 May; 186(1):105-11. View in: PubMed

  84. Ahn KH, Halpern HJ. Spatially uniform sampling in 4-D EPR spectral-spatial imaging. J Magn Reson. 2007 Mar; 185(1):152-8. View in: PubMed

  85. Haney CR, Parasca AD, Ichikawa K, Williams BB, Elas M, Pelizzari CA, Halpern HJ. Reduction of image artifacts in mice by bladder flushing with a novel double-lumen urethral catheter. Mol Imaging. 2006 Jul; 5(3):175-9. View in: PubMed

  86. Elas M, Ahn KH, Parasca A, Barth ED, Lee D, Haney C, Halpern HJ. Electron paramagnetic resonance oxygen images correlate spatially and quantitatively with Oxylite oxygen measurements. Clin Cancer Res. 2006 Jul 15; 12(14 Pt 1):4209-17. View in: PubMed

  87. Mailer C, Sundramoorthy SV, Pelizzari CA, Halpern HJ. Spin echo spectroscopic electron paramagnetic resonance imaging. Magn Reson Med. 2006 Apr; 55(4):904-12. View in: PubMed

  88. Williams BB, Pan X, Halpern HJ. EPR imaging: the relationship between CW spectra acquired from an extended sample subjected to fixed stepped gradients and the Radon transform of the resonance density. J Magn Reson. 2005 May; 174(1):88-96. View in: PubMed

  89. Bowman MK, Mailer C, Halpern HJ. The solution conformation of triarylmethyl radicals. J Magn Reson. 2005 Feb; 172(2):254-67. View in: PubMed

  90. Dreher MR, Elas M, Ichikawa K, Barth ED, Chilkoti A, Rosen GM, Halpern HJ, Dewhirst M. Nitroxide conjugate of a thermally responsive elastin-like polypeptide for noninvasive thermometry. Med Phys. 2004 Oct; 31(10):2755-62. View in: PubMed

  91. Rosen GM, Beselman A, Tsai P, Pou S, Mailer C, Ichikawa K, Robinson BH, Nielsen R, Halpern HJ, MacKerell AD. Influence of conformation on the EPR spectrum of 5,5-dimethyl-1-hydroperoxy-1-pyrrolidinyloxyl: a spin trapped adduct of superoxide. J Org Chem. 2004 Feb 20; 69(4):1321-30. View in: PubMed

  92. al-Hallaq HA, Zamora MA, Fish BL, Halpern HJ, Moulder JE, Karczmar GS. Using high spectral and spatial resolution bold MRI to choose the optimal oxygenating treatment for individual cancer patients. Adv Exp Med Biol. 2003; 530:433-40. View in: PubMed

  93. Tsai P, Ichikawa K, Mailer C, Pou S, Halpern HJ, Robinson BH, Nielsen R, Rosen GM. Esters of 5-carboxyl-5-methyl-1-pyrroline N-oxide: a family of spin traps for superoxide. J Org Chem. 2003 Oct 03; 68(20):7811-7. View in: PubMed

  94. Welch MJ, Halpern H, Kurdziel KA. Example of imaging solutions to multi-disease biological challenge--imaging of hypoxia. Acad Radiol. 2003 Aug; 10(8):887-90. View in: PubMed

  95. Carson PL, Giger M, Welch MJ, Halpern H, Kurdziel K, Vannier M, Evelhoch JL, Gazelle GS, Seltzer SE, Judy P, Hendee WR, Bourland JD. Biomedical Imaging Research Opportunities Workshop: report and recommendations. Radiology. 2003 Nov; 229(2):328-39. View in: PubMed

  96. Mailer C, Robinson BH, Williams BB, Halpern HJ. Spectral fitting: the extraction of crucial information from a spectrum and a spectral image. Magn Reson Med. 2003 Jun; 49(6):1175-80. View in: PubMed

  97. Elas M, Williams BB, Parasca A, Mailer C, Pelizzari CA, Lewis MA, River JN, Karczmar GS, Barth ED, Halpern HJ. Quantitative tumor oxymetric images from 4D electron paramagnetic resonance imaging (EPRI): methodology and comparison with blood oxygen level-dependent (BOLD) MRI. Magn Reson Med. 2003 Apr; 49(4):682-91. View in: PubMed

  98. Elas M, Parasca A, Grdina DJ, Halpern HJ. Oral administration is as effective as intraperitoneal administration of amifostine in decreasing nitroxide EPR signal decay in vivo. Biochim Biophys Acta. 2003 Mar 20; 1637(2):151-5. View in: PubMed

  99. Macdonald RL, Zhang ZD, Curry D, Elas M, Aihara Y, Halpern H, Jahromi BS, Johns L. Intracisternal sodium nitroprusside fails to prevent vasospasm in nonhuman primates. Neurosurgery. 2002 Sep; 51(3):761-8; discussion 768-70. View in: PubMed

  100. Tsai P, Porasuphatana S, Halpern HJ, Barth ED, Rosen GM. In vivo in situ detection of nitric oxide using low-frequency EPR spectroscopy. Methods Mol Biol. 2002; 196:227-37. View in: PubMed

  101. Reddy TJ, Iwama T, Halpern HJ, Rawal VH. General synthesis of persistent trityl radicals for EPR imaging of biological systems. J Org Chem. 2002 Jul 12; 67(14):4635-9. View in: PubMed

  102. Williams BB, al Hallaq H, Chandramouli GV, Barth ED, Rivers JN, Lewis M, Galtsev VE, Karczmar GS, Halpern HJ. Imaging spin probe distribution in the tumor of a living mouse with 250 MHz EPR: correlation with BOLD MRI. Magn Reson Med. 2002 Apr; 47(4):634-8. View in: PubMed

  103. Shao ZH, Vanden Hoek TL, Qin Y, Becker LB, Schumacker PT, Li CQ, Dey L, Barth E, Halpern H, Rosen GM, Yuan CS. Baicalein attenuates oxidant stress in cardiomyocytes. Am J Physiol Heart Circ Physiol. 2002 Mar; 282(3):H999-H1006. View in: PubMed

  104. Yong L, Harbridge J, Quine RW, Rinard GA, Eaton SS, Eaton GR, Mailer C, Barth E, Halpern HJ. Electron spin relaxation of triarylmethyl radicals in fluid solution. J Magn Reson. 2001 Sep; 152(1):156-61. View in: PubMed

  105. Nakamura K, Bindokas VP, Kowlessur D, Elas M, Milstien S, Marks JD, Halpern HJ, Kang UJ. Tetrahydrobiopterin scavenges superoxide in dopaminergic neurons. J Biol Chem. 2001 Sep 14; 276(37):34402-7. View in: PubMed

  106. Connell PP, Ignacio L, Haraf D, Awan AM, Halpern H, Abdalla I, Nautiyal J, Jani AB, Weichselbaum RR, Vijayakumar S. Equivalent racial outcome after conformal radiotherapy for prostate cancer: a single departmental experience. J Clin Oncol. 2001 Jan 01; 19(1):54-61. View in: PubMed

  107. Rosen GM, Tsai P, Barth ED, Dorey G, Casara P, Spedding M, Halpern HJ. A one-step synthesis of 2-(2-Pyridyl)-3H-indol-3-one N-oxide: is it an efficient spin trap for hydroxyl radical? J Org Chem. 2000 Jul 14; 65(14):4460-3. View in: PubMed

  108. Halpern HJ, Chandramouli GV, Barth ED, Yu C, Peric M, Grdina DJ, Teicher BA. Diminished aqueous microviscosity of tumors in murine models measured with in vivo radiofrequency electron paramagnetic resonance. Cancer Res. 1999 Nov 15; 59(22):5836-41. View in: PubMed

  109. Pou S, Tsai P, Porasuphatana S, Halpern HJ, Chandramouli GV, Barth ED, Rosen GM. Spin trapping of nitric oxide by ferro-chelates: kinetic and in vivo pharmacokinetic studies. Biochim Biophys Acta. 1999 Apr 19; 1427(2):216-26. View in: PubMed

  110. Rosen GM, Pou S, Halpern HJ. In vivo detection of free radicals in real time by low-frequency electron paramagnetic resonance spectroscopy. Methods Mol Biol. 1998; 108:27-35. View in: PubMed

  111. Roeske JC, Mundt AJ, Halpern H, Sweeney P, Sutton H, Powers C, Rotmensch J, Waggoner S, Weichselbaum RR. Late rectal sequelae following definitive radiation therapy for carcinoma of the uterine cervix: a dosimetric analysis. Int J Radiat Oncol Biol Phys. 1997 Jan 15; 37(2):351-8. View in: PubMed

  112. Vijayakumar S, Quadri SF, Dong L, Ignacio L, Kathuria IN, Sutton H, Halpern H. Results of a study to correlate serum prostate specific antigen and reproductive hormone levels in patients with localized prostate cancer. J Natl Med Assoc. 1995 Nov; 87(11):813-9. View in: PubMed

  113. Halpern HJ, Peric M, Yu C, Barth ED, Chandramouli GV, Makinen MW, Rosen GM. In vivo spin-label murine pharmacodynamics using low-frequency electron paramagnetic resonance imaging. Biophys J. 1996 Jul; 71(1):403-9. View in: PubMed

  114. Halpern HJ, Yu C, Peric M, Barth ED, Karczmar GS, River JN, Grdina DJ, Teicher BA. Measurement of differences in pO2 in response to perfluorocarbon/carbogen in FSa and NFSa murine fibrosarcomas with low-frequency electron paramagnetic resonance oximetry. Radiat Res. 1996 May; 145(5):610-8. View in: PubMed

  115. Vijayakumar S, Awan A, Karrison T, Culbert H, Chan S, Kolker J, Low N, Halpern H, Rubin S, Chen GT, et al. Acute toxicity during external-beam radiotherapy for localized prostate cancer: comparison of different techniques. Int J Radiat Oncol Biol Phys. 1993 Jan 15; 25(2):359-71. View in: PubMed

  116. Boisvert WE, Mustafi D, Kasa S, Makinen MW, Halpern HJ, Yu C, Barth E, Peric M. Kinetically specific spin-label substrates of liver alcohol dehydrogenase and of liver aldehyde dehydrogenase. Adv Exp Med Biol. 1993; 328:501-12. View in: PubMed

  117. Vijayakumar S, Roach M, Wara W, Chan SK, Ewing C, Rubin S, Sutton H, Halpern H, Awan A, Houghton A, et al. Effect of subcutaneous recombinant human erythropoietin in cancer patients receiving radiotherapy: preliminary results of a randomized, open-labeled, phase II trial. Int J Radiat Oncol Biol Phys. 1993 Jul 15; 26(4):721-9. View in: PubMed

  118. Ruiz-Neto PP, Halpern H, Cremonesi E. Rapid inhalation induction with halothane-nitrous oxide for myasthenic patients. Can J Anaesth. 1994 Feb; 41(2):102-6. View in: PubMed

  119. Mundt AJ, Sibley GS, Williams S, Rubin SJ, Heimann R, Halpern H, Weichselbaum RR. Patterns of failure of complete responders following high-dose chemotherapy and autologous bone marrow transplantation for metastatic breast cancer: implications for the use of adjuvant radiation therapy. Int J Radiat Oncol Biol Phys. 1994 Aug 30; 30(1):151-60. View in: PubMed

  120. Halpern HJ, Yu C, Barth E, Peric M, Rosen GM. In situ detection, by spin trapping, of hydroxyl radical markers produced from ionizing radiation in the tumor of a living mouse. Proc Natl Acad Sci U S A. 1995 Jan 31; 92(3):796-800. View in: PubMed

  121. Halpern HJ, Yu C, Peric M, Barth E, Grdina DJ, Teicher BA. Oxymetry deep in tissues with low-frequency electron paramagnetic resonance. Proc Natl Acad Sci U S A. 1994 Dec 20; 91(26):13047-51. View in: PubMed

  122. Yang FE, Vaida F, Ignacio L, Houghton A, Nauityal J, Halpern H, Sutton H, Vijayakumar S. Analysis of weekly complete blood counts in patients receiving standard fractionated partial body radiation therapy. Int J Radiat Oncol Biol Phys. 1995 Oct 15; 33(3):617-17. View in: PubMed

  123. Miller DC, Goodman ML, Pilch BZ, Shi SR, Dickersin GR, Halpern H, Norris CM. Mixed olfactory neuroblastoma and carcinoma. A report of two cases. Cancer. 1984 Nov 01; 54(9):2019-28. View in: PubMed

  124. Rosen GM, Halpern HJ, Brunsting LA, Spencer DP, Strauss KE, Bowman MK, Wechsler AS. Direct measurement of nitroxide pharmacokinetics in isolated hearts situated in a low-frequency electron spin resonance spectrometer: implications for spin trapping and in vivo oxymetry. Proc Natl Acad Sci U S A. 1988 Oct; 85(20):7772-6. View in: PubMed

  125. Hallahan DE, Michel AG, Halpern HJ, Awan AM, Desser R, Bitran J, Recant W, Wyman B, Spelbring DR, Weichselbaum RR. Breast conserving surgery and definitive irradiation for early stage breast cancer. Int J Radiat Oncol Biol Phys. 1989 Dec; 17(6):1211-6. View in: PubMed

  126. Rader JS, Haraf DJ, Halpern HJ, Rotmensch J, Spelbring DR, Sutton H, Javaheri G, Weichselbaum RR. Radiation therapy in the treatment of cervical cancer: the University of Chicago/Michael Reese Hospital experience. J Surg Oncol. 1990 Jul; 44(3):157-65. View in: PubMed

  127. Rotmensch J, Rubin SJ, Sutton HG, Javaheri G, Halpern HJ, Schwartz JL, Stewart M, Weichselbaum RR, Herbst AL. Preoperative radiotherapy followed by radical vulvectomy with inguinal lymphadenectomy for advanced vulvar carcinomas. Gynecol Oncol. 1990 Feb; 36(2):181-4. View in: PubMed

  128. Rosen GM, Halpern HJ. Spin trapping biologically generated free radicals: correlating formation with cellular injury. Methods Enzymol. 1990; 186:611-21. View in: PubMed

  129. Kolker JD, Halpern HJ, Krishnasamy S, Brown F, Dohrmann G, Ferguson L, Hekmatpanah J, Mullan J, Wollman R, Blough R, et al. "Instant-mix" whole brain photon with neutron boost radiotherapy for malignant gliomas. Int J Radiat Oncol Biol Phys. 1990 Aug; 19(2):409-14. View in: PubMed

  130. Vijayakumar S, Low N, Chen GT, Myrianthopoulos L, Culbert H, Chiru P, Spelbring D, Awan A, Rosenberg I, Halpern H, et al. Beams eye view-based photon radiotherapy I. Int J Radiat Oncol Biol Phys. 1991 Nov; 21(6):1575-86. View in: PubMed

  131. Vijayakumar S, Myrianthopoulos LC, Rosenberg I, Halpern HJ, Low N, Chen GT. Optimization of radical radiotherapy with beam's eye view techniques for non-small cell lung cancer. Int J Radiat Oncol Biol Phys. 1991 Aug; 21(3):779-88. View in: PubMed

  132. Halpern HJ, Jaffe DR, Nguyen TD, Haraf DJ, Spencer DP, Bowman MK, Weichselbaum RR, Diamond AM. Measurement of bioreduction rates of cells with distinct responses to ionizing radiation and cisplatin. Biochim Biophys Acta. 1991 Jul 10; 1093(2-3):121-4. View in: PubMed

  133. Pou S, Peric M, Halpern HJ, Rosen GM. Use of a low-frequency ESR spectrometer: implications for spin-trapping free radicals, in situ. Free Radic Res Commun. 1991; 12-13 Pt 1:39-46. View in: PubMed

  134. Myrianthopoulos LC, Chen GT, Vijayakumar S, Halpern HJ, Spelbring DR, Pelizzari CA. Beam's eye view volumetrics: an aid in rapid treatment plan development and evaluation. Int J Radiat Oncol Biol Phys. 1992; 23(2):367-75. View in: PubMed

  135. Chen GT, Spelbring DR, Pelizzari CA, Balter JM, Myrianthopoulos LC, Vijayakumar S, Halpern H. The use of beam's eye view volumetrics in the selection of non-coplanar radiation portals. Int J Radiat Oncol Biol Phys. 1992; 23(1):153-63. View in: PubMed

  136. Vijayakumar S, Quadri SF, Karrison TG, Trinidad CO, Chan SK, Halpern HJ, Rubin SJ, Sutton HG. Localized prostate cancer: use of serial prostate-specific antigen measurements during radiation therapy. Radiology. 1992 Jul; 184(1):271-4. View in: PubMed