GIRARD Olivier

Research Engineer (PhD)

at AMU

Operational manager of the Siemens MAGNETOM 7T Terra system
Research on quantitative imaging and Ultra High Field
Expert of ihMT and Microstuctural MRI
Training of students on MR physics

Research Engineer (PhD)

Detailed Activities

My current research interests are focused on new endogenous contrast mechanisms and ultra-high field (UHF) MRI. UHF MRI offers unique opportunities for improved spatial resolution as well as enhanced sensitivity and contrast. To reach these goals UHF MRI require new methodological developments that drive the global MR research effort with outcomes benefiting to the whole MRI community. In addition, a variety of advanced quantitative MRI techniques have emerged (e.g. inhomogeneous Magnetization Transfer – ihMT, Quantitative Susceptibility Mapping – QSM, Ultrashort Echo-Time imaging – UTE, Arterial Spin Labeling – ASL) allowing to reveal new kinds of MR contrasts. These allow for a more precise and powerful tissue characterization, especially relative to tissue microstructure and function. There are high synergies and challenges combining advanced quantitative techniques and UHF MRI. My work focus on developing new methodology to that end, ultimately providing new tools to push further the boundaries of what MRI can provide to researchers and clinicians.

I am responsible of the 7T human MRI platform and am co-leading the ihMT research program with Guillaume Duhamel at CRMBM. This new contrast mechanism allows revealing dipolar order within macromolecules, a yet unexplored degree of freedom in MRI, and has promising applications for myelin imaging. We have pioneered this new technique with the Beth Israel Deaconess Medical Center – BIDMC, Harvard Medical School.

Keywords

  • Inhomogenous Magnetization Transfer (ihMT)
  • Microstructure/architecture
  • MR Physics / MR Method developments
  • New Contrasts
  • New MR Biomarkers
  • Quantitative MRI
  • Ultra-high field MRI
  • Molecular Imaging

General Information

– 2016-Ongoing : Member of the communication work-group at CRMBM
– 2016-2021 : Board member of the French NMR society (GERM – Groupement d’Etudes de Résonance Magnétique)
– 2017-2019 : Member of the Web Editorial Board of the international MRI society (ISMRM – International Society for Magnetic Resonance in Medicine)
– 2013 : Junior Fellow of the ISMRM (1 year Observer in the Education Committee)

Research Projects

Publications :

Radunsky, D., Solomon, C., Stern, N., Blumenfeld-Katzir, T., Filo, S., Mezer, A., Karsa, A., Shmueli, K., Soustelle, L., Duhamel, G., Girard, O.M., Kepler, G., Shrot, S., Hoffmann, C. and Ben-Eliezer, N. (2024) ‘A comprehensive protocol for quantitative magnetic resonance imaging of the brain at 3 Tesla’, PloS One, 19(5), p. e0297244. Available at: https://doi.org/10.1371/journal.pone.0297244.
Soustelle, L., Troalen, T., Hertanu, A., Ranjeva, J.-P., Guye, M., Varma, G., Alsop, D.C., Duhamel, G. and Girard, O.M. (2023) ‘Quantitative magnetization transfer MRI unbiased by on-resonance saturation and dipolar order contributions’, Magnetic Resonance in Medicine, 90(3), pp. 875–893. Available at: https://doi.org/10.1002/mrm.29678.
Hertanu, A., Soustelle, L., Buron, J., Le Priellec, J., Cayre, M., Le Troter, A., Prevost, V.H., Ranjeva, J.-P., Varma, G., Alsop, D.C., Durbec, P., Girard, O.M. and Duhamel, G. (2023) ‘Inhomogeneous Magnetization Transfer (ihMT) imaging in the acute cuprizone mouse model of demyelination/remyelination’, NeuroImage, 265, p. 119785. Available at: https://doi.org/10.1016/j.neuroimage.2022.119785.
Taso, M., Munsch, F., Girard, O.M., Duhamel, G., Alsop, D.C. and Varma, G. (2023) ‘Fast-spin-echo versus rapid gradient-echo for 3D magnetization-prepared acquisitions: Application to inhomogeneous magnetization transfer’, Magnetic Resonance in Medicine, 89(2), pp. 550–564. Available at: https://doi.org/10.1002/mrm.29461.
Alsop, D.C., Ercan, E., Girard, O.M., Mackay, A.L., Michal, C.A., Varma, G., Vinogradov, E. and Duhamel, G. (2023) ‘Inhomogeneous magnetization transfer imaging: Concepts and directions for further development’, NMR in Biomedicine, 36(6), p. e4808. Available at: https://doi.org/10.1002/nbm.4808.
Forodighasemabadi, A., Baucher, G., Soustelle, L., Troalen, T., Girard, O.M., Guye, M., Grisoli, J.-B., Ranjeva, J.-P., Duhamel, G. and Callot, V. (2022) ‘Spinal cord and brain tissue impairments as long-term effects of rugby practice? An exploratory study based on T1 and ihMTsat measures’, NeuroImage. Clinical, 35, p. 103124. Available at: https://doi.org/10.1016/j.nicl.2022.103124.
Vergara Gomez, T.S., Dubois, M., Rustomji, K., Georget, E., Antonakakis, T., Vignaud, A., Rapacchi, S., Girard, O.M., Kober, F., Enoch, S. and Abdeddaim, R. (2022) ‘Hilbert fractal inspired dipoles for passive RF shimming in ultra-high field MRI’, Photonics and Nanostructures - Fundamentals and Applications, 48, p. 100988. Available at: https://doi.org/10.1016/j.photonics.2021.100988.
Soustelle, L., Troalen, T., Hertanu, A., Mchinda, S., Ranjeva, J.-P., Guye, M., Varma, G., Alsop, D.C., Duhamel, G. and Girard, O.M. (2022) ‘A strategy to reduce the sensitivity of inhomogeneous magnetization transfer (ihMT) imaging to radiofrequency transmit field variations at 3 T’, Magnetic Resonance in Medicine, 87(3), pp. 1346–1359. Available at: https://doi.org/10.1002/mrm.29055.
Brun, G., Testud, B., Girard, O.M., Lehmann, P., de Rochefort, L., Besson, P., Massire, A., Ridley, B., Girard, N., Guye, M., Ranjeva, J.-P. and Le Troter, A. (2022) ‘Automatic segmentation of deep grey nuclei using a high-resolution 7T magnetic resonance imaging atlas—Quantification of T1 values in healthy volunteers’, European Journal of Neuroscience, 55(2), pp. 438–460. Available at: https://doi.org/10.1111/ejn.15575.
Hertanu, A., Soustelle, L., Le Troter, A., Buron, J., Le Priellec, J., Carvalho, V.N.D., Cayre, M., Durbec, P., Varma, G., Alsop, D.C., Girard, O.M. and Duhamel, G. (2022) ‘T1D-weighted ihMT imaging – Part I. Isolation of long- and short-T1D components by T1D-filtering’, Magnetic Resonance in Medicine, 87(5), pp. 2313–2328. Available at: https://doi.org/10.1002/mrm.29139.
Hertanu, A., Soustelle, L., Buron, J., Le Priellec, J., Cayre, M., Le Troter, A., Varma, G., Alsop, D.C., Durbec, P., Girard, O.M. and Duhamel, G. (2022) ‘T1D-weighted ihMT imaging – Part II. Investigating the long- and short-T1D components correlation with myelin content. Comparison with R1 and the macromolecular proton fraction’, Magnetic Resonance in Medicine, 87(5), pp. 2329–2346. Available at: https://doi.org/10.1002/mrm.29140.
Massire, A., Seiler, C., Troalen, T., Girard, O.M., Lehmann, P., Brun, G., Bartoli, A., Audoin, B., Bartolomei, F., Pelletier, J., Callot, V., Kober, T., Ranjeva, J.-P. and Guye, M. (2021) ‘T1-Based Synthetic Magnetic Resonance Contrasts Improve Multiple Sclerosis and Focal Epilepsy Imaging at 7 T’, Investigative Radiology, 56(2), pp. 127–133. Available at: https://doi.org/10.1097/RLI.0000000000000718.
Munsch, F., Varma, G., Taso, M., Girard, O., Guidon, A., Duhamel, G. and Alsop, D.C. (2021) ‘Characterization of the cortical myeloarchitecture with inhomogeneous magnetization transfer imaging (ihMT)’, NeuroImage, 225, p. 117442. Available at: https://doi.org/10.1016/j.neuroimage.2020.117442.
Varma, G., Munsch, F., Burns, B., Duhamel, G., Girard, O.M., Guidon, A., Lebel, R.M. and Alsop, D.C. (2020) ‘Three-dimensional inhomogeneous magnetization transfer with rapid gradient-echo (3D ihMTRAGE) imaging’, Magnetic Resonance in Medicine, 84(6), pp. 2964–2980. Available at: https://doi.org/10.1002/mrm.28324.
Rasoanandrianina, H., Demortière, S., Trabelsi, A., Ranjeva, J.P., Girard, O., Duhamel, G., Guye, M., Pelletier, J., Audoin, B. and Callot, V. (2020) ‘Sensitivity of the Inhomogeneous Magnetization Transfer Imaging Technique to Spinal Cord Damage in Multiple Sclerosis’, American Journal of Neuroradiology, 41(5), pp. 929–937. Available at: https://doi.org/10.3174/ajnr.A6554.
Carvalho, V.N.D., Hertanu, A., Grélard, A., Mchinda, S., Soustelle, L., Loquet, A., Dufourc, E.J., Varma, G., Alsop, D.C., Thureau, P., Girard, O.M. and Duhamel, G. (2020) ‘MRI assessment of multiple dipolar relaxation time (T1D) components in biological tissues interpreted with a generalized inhomogeneous magnetization transfer (ihMT) model’, Journal of Magnetic Resonance (San Diego, Calif.: 1997), 311, p. 106668. Available at: https://doi.org/10.1016/j.jmr.2019.106668.
Duhamel, G., Prevost, V.H., Cayre, M., Hertanu, A., Mchinda, S., Carvalho, V.N., Varma, G., Durbec, P., Alsop, D.C. and Girard, O.M. (2019) ‘Validating the sensitivity of inhomogeneous magnetization transfer (ihMT) MRI to myelin with fluorescence microscopy’, NeuroImage, 199, pp. 289–303. Available at: https://doi.org/10.1016/j.neuroimage.2019.05.061.
Varma, G., Girard, O.M., Mchinda, S., Prevost, V.H., Grant, A.K., Duhamel, G. and Alsop, D.C. (2018) ‘Low duty-cycle pulsed irradiation reduces magnetization transfer and increases the inhomogeneous magnetization transfer effect’, Journal of Magnetic Resonance (San Diego, Calif.: 1997), 296, pp. 60–71. Available at: https://doi.org/10.1016/j.jmr.2018.08.004.
Mchinda, S., Varma, G., Prevost, V.H., Le Troter, A., Rapacchi, S., Guye, M., Pelletier, J., Ranjeva, J.-P., Alsop, D.C., Duhamel, G. and Girard, O.M. (2018) ‘Whole brain inhomogeneous magnetization transfer (ihMT) imaging: Sensitivity enhancement within a steady-state gradient echo sequence’, Magnetic Resonance in Medicine, 79(5), pp. 2607–2619. Available at: https://doi.org/10.1002/mrm.26907.
Van Obberghen, E., Mchinda, S., le Troter, A., Prevost, V.H., Viout, P., Guye, M., Varma, G., Alsop, D.C., Ranjeva, J.-P., Pelletier, J., Girard, O. and Duhamel, G. (2018) ‘Evaluation of the Sensitivity of Inhomogeneous Magnetization Transfer (ihMT) MRI for Multiple Sclerosis’, AJNR. American journal of neuroradiology, 39(4), pp. 634–641. Available at: https://doi.org/10.3174/ajnr.A5563.
Rasoanandrianina, H., Grapperon, A.-M., Taso, M., Girard, O.M., Duhamel, G., Guye, M., Ranjeva, J.-P., Attarian, S., Verschueren, A. and Callot, V. (2017) ‘Region-specific impairment of the cervical spinal cord (SC) in amyotrophic lateral sclerosis: A preliminary study using SC templates and quantitative MRI (diffusion tensor imaging/inhomogeneous magnetization transfer)’, NMR in biomedicine, 30(12). Available at: https://doi.org/10.1002/nbm.3801.
Varma, G., Girard, O.M., Prevost, V.H., Grant, A.K., Duhamel, G. and Alsop, D.C. (2017) ‘In vivo measurement of a new source of contrast, the dipolar relaxation time, T1D , using a modified inhomogeneous magnetization transfer (ihMT) sequence’, Magnetic Resonance in Medicine, 78(4), pp. 1362–1372. Available at: https://doi.org/10.1002/mrm.26523.
Bydder, M., Rapacchi, S., Girard, O., Guye, M. and Ranjeva, J.-P. (2017) ‘Trimmed autocalibrating k-space estimation based on structured matrix completion’, Magnetic Resonance Imaging, 43, pp. 88–94. Available at: https://doi.org/10.1016/j.mri.2017.07.015.
Prevost, V.H., Girard, O.M., Mchinda, S., Varma, G., Alsop, D.C. and Duhamel, G. (2017) ‘Optimization of inhomogeneous magnetization transfer (ihMT) MRI contrast for preclinical studies using dipolar relaxation time (T1D) filtering’, NMR in Biomedicine, 30(6). Available at: https://doi.org/10.1002/nbm.3706.
Girard, O.M., Callot, V., Prevost, V.H., Robert, B., Taso, M., Ribeiro, G., Varma, G., Rangwala, N., Alsop, D.C. and Duhamel, G. (2017) ‘Magnetization transfer from inhomogeneously broadened lines (ihMT): Improved imaging strategy for spinal cord applications’, Magnetic Resonance in Medicine, 77, pp. 581–591. Available at: https://doi.org/10.1002/mrm.26134.
Prevost, V.H., Girard, O.M., Varma, G., Alsop, D.C. and Duhamel, G. (2016) ‘Minimizing the effects of magnetization transfer asymmetry on inhomogeneous magnetization transfer (ihMT) at ultra-high magnetic field (11.75 T)’, Magma (New York, N.Y.), 29(4), pp. 699–709. Available at: https://doi.org/10.1007/s10334-015-0523-2.
Taso, M., Girard, O.M., Duhamel, G., Le Troter, A., Feiweier, T., Guye, M., Ranjeva, J.-P. and Callot, V. (2016) ‘Tract-specific and age-related variations of the spinal cord microstructure: a multi-parametric MRI study using diffusion tensor imaging (DTI) and inhomogeneous magnetization transfer (ihMT)’, NMR in biomedicine, 29(6), pp. 817–832. Available at: https://doi.org/10.1002/nbm.3530.
Prevost, V.H., Girard, O.M., Callot, V., Cozzone, P.J. and Duhamel, G. (2015) ‘Fast imaging strategies for mouse kidney perfusion measurement with pseudocontinuous arterial spin labeling (pCASL) at ultra high magnetic field (11.75 tesla)’, Journal of Magnetic Resonance Imaging, 42(4), pp. 999–1008. Available at: https://doi.org/10.1002/jmri.24874.
Varma, G., Girard, O.M., Prevost, V.H., Grant, A.K., Duhamel, G. and Alsop, D.C. (2015) ‘Interpretation of magnetization transfer from inhomogeneously broadened lines (ihMT) in tissues as a dipolar order effect within motion restricted molecules’, Journal of Magnetic Resonance (San Diego, Calif.: 1997), 260, pp. 67–76. Available at: https://doi.org/10.1016/j.jmr.2015.08.024.
Girard, O.M., Prevost, V.H., Varma, G., Cozzone, P.J., Alsop, D.C. and Duhamel, G. (2015) ‘Magnetization transfer from inhomogeneously broadened lines (ihMT): Experimental optimization of saturation parameters for human brain imaging at 1.5 Tesla’, Magnetic Resonance in Medicine, 73(6), pp. 2111–2121. Available at: https://doi.org/10.1002/mrm.25330.
Laistler, E., Poirier-Quinot, M., Lambert, S.A., Dubuisson, R.-M., Girard, O.M., Moser, E., Darrasse, L. and Ginefri, J.-C. (2015) ‘In vivo MR imaging of the human skin at subnanoliter resolution using a superconducting surface coil at 1.5 Tesla’, Journal of magnetic resonance imaging: JMRI, 41(2), pp. 496–504. Available at: https://doi.org/10.1002/jmri.24549.
Duhamel, G., Prevost, V., Girard, O.M., Callot, V. and Cozzone, P.J. (2014) ‘High-resolution mouse kidney perfusion imaging by pseudo-continuous arterial spin labeling at 11.75T’, Magnetic Resonance in Medicine, 71(3), pp. 1186–1196. Available at: https://doi.org/10.1002/mrm.24740.
Girard, O.M., de Rochefort, L., Poirier-Quinot, M., Darrasse, L. and Mattrey, R.F. (2013) ‘Quantification strategies for MRI’, Molecular Imaging Techniques: New Frontiers, pp. 66–80. Available at: https://doi.org/10.4155/ebo.13.146.
Poirier-Quinot, M., de Rochefort, L., Girard, O.M. and Darrasse, L. (2013) ‘MRI: recent advances and new horizons’, Molecular Imaging Techniques: New Frontiers, pp. 34–49. Available at: https://doi.org/10.4155/ebo.13.217.
Liau, J., Shiehmorteza, M., Girard, O.M., Sirlin, C.B. and Bydder, M. (2013) ‘Evaluation of MRI fat fraction in the liver and spine pre and post SPIO infusion’, Magnetic Resonance Imaging, 31(6), pp. 1012–1016. Available at: https://doi.org/10.1016/j.mri.2013.01.016.
Girard, O.M., Ramirez, R., McCarty, S. and Mattrey, R.F. (2012) ‘Toward absolute quantification of iron oxide nanoparticles as well as cell internalized fraction using multiparametric MRI’, Contrast Media & Molecular Imaging, 7(4), pp. 411–417. Available at: https://doi.org/10.1002/cmmi.1467.
Agemy, L., Friedmann-Morvinski, D., Kotamraju, V.R., Roth, L., Sugahara, K.N., Girard, O.M., Mattrey, R.F., Verma, I.M. and Ruoslahti, E. (2011) ‘Targeted nanoparticle enhanced proapoptotic peptide as potential therapy for glioblastoma’, Proceedings of the National Academy of Sciences, 108(42), pp. 17450–17455. Available at: https://doi.org/10.1073/pnas.1114518108.
Bydder, M., Girard, O. and Hamilton, G. (2011) ‘Mapping the double bonds in triglycerides’, Magnetic Resonance Imaging, 29(8), pp. 1041–1046. Available at: https://doi.org/10.1016/j.mri.2011.07.004.
Girard, O.M., Du, J., Agemy, L., Sugahara, K.N., Kotamraju, V.R., Ruoslahti, E., Bydder, G.M. and Mattrey, R.F. (2011) ‘Optimization of iron oxide nanoparticle detection using ultrashort echo time pulse sequences: Comparison of T1, T2*, and synergistic T1 − T2* contrast mechanisms’, Magnetic Resonance in Medicine, 65(6), pp. 1649–1660. Available at: https://doi.org/10.1002/mrm.22755.
Carl, M., Sanal, H.T., Diaz, E., Du, J., Girard, O., Statum, S., Znamirowski, R. and Chung, C.B. (2011) ‘Optimizing MR signal contrast of the temporomandibular joint disk’, Journal of Magnetic Resonance Imaging, 34(6), pp. 1458–1464. Available at: https://doi.org/10.1002/jmri.22810.
Agemy, L., Sugahara, K.N., Kotamraju, V.R., Gujraty, K., Girard, O.M., Kono, Y., Mattrey, R.F., Park, J.-H., Sailor, M.J., Jimenez, A.I., Cativiela, C., Zanuy, D., Sayago, F.J., Aleman, C., Nussinov, R. and Ruoslahti, E. (2010) ‘Nanoparticle-induced vascular blockade in human prostate cancer’, Blood, 116(15), pp. 2847–2856. Available at: https://doi.org/10.1182/blood-2010-03-274258.
Bydder, M., Shiehmorteza, M., Yokoo, T., Sugay, S., Middleton, M.S., Girard, O., Schroeder, M.E., Wolfson, T., Gamst, A. and Sirlin, C. (2010) ‘Assessment of liver fat quantification in the presence of iron’, Magnetic Resonance Imaging, 28(6), pp. 767–776. Available at: https://doi.org/10.1016/j.mri.2010.03.017.
Sugahara, K.N., Teesalu, T., Karmali, P.P., Kotamraju, V.R., Agemy, L., Girard, O.M., Hanahan, D., Mattrey, R.F. and Ruoslahti, E. (2009) ‘Tissue-Penetrating Delivery of Compounds and Nanoparticles into Tumors’, Cancer Cell, 16(6), pp. 510–520. Available at: https://doi.org/10.1016/j.ccr.2009.10.013.
Poirier-Quinot, M., Ginefri, J.-C., Girard, O., Robert, P. and Darrasse, L. (2008) ‘Performance of a miniature high-temperature superconducting (HTS) surface coil for in vivo microimaging of the mouse in a standard 1.5T clinical whole-body scanner’, Magnetic Resonance in Medicine, 60(4), pp. 917–927. Available at: https://doi.org/10.1002/mrm.21605.
Girard, O., Ginefri, J.-C., Poirier-Quinot, M. and Darrasse, L. (2007) ‘Method for nonlinear characterization of radio frequency coils made of high temperature superconducting material in view of magnetic resonance imaging applications’, The Review of scientific instruments, 78(12), p. 124703. Available at: https://doi.org/10.1063/1.2825241.
Ginefri, J.-C., Poirier-Quinot, M., Girard, O. and Darrasse, L. (2007) ‘Technical aspects: Development, manufacture and installation of a cryo-cooled HTS coil system for high-resolution in-vivo imaging of the mouse at 1.5 T’, Methods, 43(1), pp. 54–67. Available at: https://doi.org/10.1016/j.ymeth.2007.03.011.
Woytasik, M., Ginefri, J.-C., Raynaud, J.-S., Poirier-Quinot, M., Dufour-Gergam, E., Grandchamp, J.-P., Girard, O., Robert, P., Gilles, J.-P., Martincic, E. and Darrasse, L. (2007) ‘Characterization of flexible RF microcoils dedicated to local MRI’, Microsystem Technologies-Micro-and Nanosystems-Information Storage and Processing Systems, 13(11–12), pp. 1575–1580. Available at: https://doi.org/10.1007/s00542-006-0277-x.