C. Kagadis, G. Loudos, K. Katsanos, S. Langer, and G. Nikiforidis, small animal imaging: Current status and future prospects, Medical Physics, vol.65, issue.2, p.6421, 2010.
DOI : 10.1118/1.3491806

R. Yao, R. Lecomte, and E. Crawford, Small-Animal PET: What Is It, and Why Do We Need It?, Journal of Nuclear Medicine Technology, vol.40, issue.3, pp.157-165, 2012.
DOI : 10.2967/jnmt.111.098632

B. Dogdas, Image registration with applications to multimodal small animal imaging, 2007.

B. Pichler, H. Wehrl, A. Kolb, M. S. Judenhofer, . Pet et al., Positron Emission Tomography/Magnetic Resonance Imaging: The Next Generation of Multimodality Imaging?, Seminars in Nuclear Medicine, vol.38, issue.3, pp.199-208, 2008.
DOI : 10.1053/j.semnuclmed.2008.02.001

F. Brunotte, H. Haas, B. Collin, A. Pharmd, S. Oudot et al., Integrated PET/MRI in preclinical studies State of the art, pp.1144-1152, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00953753

R. P. Woods, J. C. Mazziotta, and S. R. Cherry, MRI-PET Registration with Automated Algorithm, Journal of Computer Assisted Tomography, vol.17, issue.4, pp.536-546, 1993.
DOI : 10.1097/00004728-199307000-00004

A. Collignon, F. Maes, D. Delaere, P. Vandermeulen, G. Suetens et al., Automated multi-modality image registration based on information theory, Information Processing in Medical Imaging, pp.263-274, 1995.

J. P. Pluim, J. B. Maintz, and M. Viergever, IEEE transactions on Medical Imaging, issue.8, pp.809-814

, Figure 6 Registration successes of the 7 datasets in %

B. Ardekani, M. Braun, B. Hutton, I. Kanno, and H. Lida, A Fully Automatic Multimodality Image Registration Algorithm, Journal of Computer Assisted Tomography, vol.19, issue.4, pp.615-623, 1995.
DOI : 10.1097/00004728-199507000-00022

D. Mattes, D. R. Haynor, H. Vesselle, T. Lewellen, and W. Eubank, PET-CT image registration in the chest using free-form deformations, IEEE Transactions on Medical Imaging, vol.22, issue.1, pp.120-128, 2003.
DOI : 10.1109/TMI.2003.809072

J. Vaquero, M. Desco, and C. Pet, PET, CT, and MR image registration of the rat brain and skull, IEEE Transactions on Nuclear Science, vol.48, issue.4, pp.1440-1445, 2001.
DOI : 10.1109/23.958376

R. Woods, S. Cherry, and J. Mazziotta, Rapid Automated Algorithm for Aligning and Reslicing PET Images, Journal of Computer Assisted Tomography, vol.16, issue.4, pp.620-635
DOI : 10.1097/00004728-199207000-00024

M. Preuss, P. Werner, H. Barthel, U. Nestler, F. W. Hirsch et al., A PET-MRI registration technique for PET studies of the rat brain, Nuclear Medicine and Biology, vol.27, issue.2, pp.121-125, 2000.

M. Bernier, R. Lepage, L. Lecomte, L. Tremblay, L. Dor´e-savard et al., Free-Form B-spline Deformation Model for Groupwise Registration, Conference Proceeding International Society of Magnetic Resonance in Medicine(ISMRM)15] N.L. Baisa. MRI-PET Registration With Automated Algorithm in Preclinical Studies, p.3255, 2011.

H. J. Johnson, M. Mccormick, and L. Ibanez, The ITK Software Guide

. Saruchi, Adaptive Sigmoid Function to Enhance Low Contrast Images, International Journal of Computer Applications, vol.55, issue.4, pp.45-49, 2012.
DOI : 10.5120/8747-2634

N. M. Alpert, J. F. Bradshaw, D. Kennedy, and J. A. Correia, The Principal Axes Transformation A Method for Image Registration, Journal of Nuclear Medicine, issue.10, pp.311717-1722, 1990.

Z. Lu and W. Chen, Fast and Robust 3-D Image Registration Algorithm Based on Principal Component Analysis, 2007 1st International Conference on Bioinformatics and Biomedical Engineering, pp.872-875, 2007.
DOI : 10.1109/ICBBE.2007.227

J. Kybic and M. Unser, IEEE transactions on image processing : a publication of the, IEEE Signal Processing Society, issue.11, pp.1879-2890

B. Likar and F. Pernu?s, A hierarchical approach to elastic registration based on mutual information, Image and Vision Computing, vol.19, issue.1-2, pp.33-44, 2001.
DOI : 10.1016/S0262-8856(00)00053-6

J. V. Hajnal, D. L. Hill, and D. J. Hawkes, Medical image registration, 2001.
DOI : 10.1201/9781420042474
URL : https://hal.archives-ouvertes.fr/inria-00615977

, Figure 6 Registration successes of the 7 datasets in %

J. P. Pluim, J. B. Maintz, and M. Viergever, Mutual-information-based registration of medical images: a survey, IEEE Transactions on Medical Imaging, vol.22, issue.8, pp.986-1004, 2003.
DOI : 10.1109/TMI.2003.815867

P. Th´evenaz, T. Blu, and M. Unser, Handbook of medical imaging. chapter Image Interpolation and Resampling, pp.393-420, 2000.

C. Studholme, D. L. Hill, and D. Hawkes, Automated three-dimensional registration of magnetic resonance and positron emission tomography brain images by multiresolution optimization of voxel similarity measures, Medical Physics, vol.19, issue.1, pp.25-35, 1997.
DOI : 10.1097/00004728-199501000-00022

F. Maes, A. Collignon, D. Vandermeulen, G. Marchal, and P. Suetens, Multimodality image registration by maximization of mutual information, IEEE Transactions on Medical Imaging, vol.16, issue.2, pp.187-198, 1997.
DOI : 10.1109/42.563664

R. Xu, Y. Chen, S. Tang, S. Morikawa, and Y. Kurumi, Parzen-Window Based Normalized Mutual Information for Medical Image Registration, IEICE Transactions on Information and Systems, vol.91, issue.1, pp.132-144, 2010.
DOI : 10.1093/ietisy/e91-d.1.132

J. Nocedal and S. J. Wright, Numerical Optimization, 1999.
DOI : 10.1007/b98874

D. Mattes, D. R. Haynor, H. Vesselle, T. K. Lewellyn, and W. Eubank, Nonrigid multimodality image registration, SPIE Medical Imaging, pp.1609-1620, 2001.
DOI : 10.1117/12.431046

R. Byrd, P. Lu, J. Nocedal, and C. Zhu, A Limited Memory Algorithm for Bound Constrained Optimization, SIAM Journal on Scientific Computing, vol.16, issue.5, pp.1190-1208, 1995.
DOI : 10.1137/0916069
URL : https://digital.library.unt.edu/ark:/67531/metadc666315/m2/1/high_res_d/204262.pdf

J. C. Moore, Visualizing with VTK, Linux Journal, vol.20, pp.93-100, 1998.