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Volumn 33, Issue 3, 2014, Pages 708-725

Nonrigid registration of ultrasound and MRI using contextual conditioned mutual information

Author keywords

Magnetic resonance; Mutual information; Registration; Surgical guidance; Ultrasound

Indexed keywords

COST FUNCTIONS; HOSPITAL DATA PROCESSING; ULTRASONICS;

EID: 84896285316     PISSN: 02780062     EISSN: None     Source Type: Journal    
DOI: 10.1109/TMI.2013.2294630     Document Type: Article
Times cited : (56)

References (56)
  • 1
    • 0030088712 scopus 로고    scopus 로고
    • Multi-modal volume registration by maximization of mutual information
    • W.Wells, P. Viola, H. Atsumid, S. Nakajimae, and R. Kikinis, "Multimodal volume registration maximization of mutual information," Med. Imag. Anal., vol. 1, no. 1, pp. 35-51, 1996. (Pubitemid 126421955)
    • (1996) Medical Image Analysis , vol.1 , Issue.1 , pp. 35-51
    • Wells III, W.M.1    Viola, P.2    Atsumi, H.3    Nakajima, S.4    Kikinis, R.5
  • 3
    • 0043028206 scopus 로고    scopus 로고
    • Mutual-information-based registration of medical images: A survey
    • Aug.
    • J. Pluim, J. Maintz, andM.Viergever, "Mutual-information-based registration of medical images: A survey," IEEE Trans. Med. Imag., vol. 22, no. 8, pp. 986-1004, Aug. 2003.
    • (2003) IEEE Trans. Med. Imag. , vol.22 , Issue.8 , pp. 986-1004
    • Pluim, J.1    Maintz, J.2    Viergever, M.3
  • 4
    • 0034238080 scopus 로고    scopus 로고
    • Image registration by maximization of combined mutual information and gradient information
    • DOI 10.1109/42.876307
    • J. Pluim, J. Maintz, and M. Viergever, "Image registration by maximization of combined mutual information and gradient information," IEEE Trans Med. Imag., vol. 19, no. 8, pp. 809-814, Aug. 2000. (Pubitemid 32031207)
    • (2000) IEEE Transactions on Medical Imaging , vol.19 , Issue.8 , pp. 809-814
    • Pluim, J.P.W.1    Maintz, J.B.A.2    Viergever, M.A.3
  • 5
    • 33846211066 scopus 로고    scopus 로고
    • Information theoretic deformable registration using local image information
    • B. Karaali, "Information theoretic deformable registration using local image information," Int. J. Comp. Vis., vol. 72, no. 3, pp. 219-237, 2007.
    • (2007) Int. J. Comp. Vis. , vol.72 , Issue.3 , pp. 219-237
    • Karaali, B.1
  • 6
    • 84870523404 scopus 로고    scopus 로고
    • Multi-modal image registration based on gradient orientations of minimal uncertainty
    • Dec.
    • D. D. Nigris, D. L. Collins, and T. Arbel, "Multi-modal image registration based on gradient orientations of minimal uncertainty," IEEE Trans. Med. Imag., vol. 30, no. 12, pp. 2343-2354, Dec. 2012.
    • (2012) IEEE Trans. Med. Imag. , vol.30 , Issue.12 , pp. 2343-2354
    • Nigris, D.D.1    Collins, D.L.2    Arbel, T.3
  • 7
    • 82355161020 scopus 로고    scopus 로고
    • Entropy and Laplacian images: Structural representations for multi-modal registration
    • C. Wachinger and N. Navab, "Entropy and Laplacian images: Structural representations for multi-modal registration," Med. Image Anal., vol. 16, no. 1, pp. 1-17, 2012.
    • (2012) Med. Image Anal. , vol.16 , Issue.1 , pp. 1-17
    • Wachinger, C.1    Navab, N.2
  • 8
    • 84866457193 scopus 로고    scopus 로고
    • MIND: Modality independent neighbourhood descriptor formulti-modal deformable registration
    • M. Heinrich, M. Jenkinson, M. Bhushan, T. Matin, F. Gleeson, M. Brady, and J. Schnabel, "MIND: Modality independent neighbourhood descriptor formulti-modal deformable registration,"Med. Image Anal., vol. 16, no. 7, pp. 1423-1435, 2012.
    • (2012) Med. Image Anal , vol.16 , Issue.7 , pp. 1423-1435
    • Heinrich, M.1    Jenkinson, M.2    Bhushan, M.3    Matin, T.4    Gleeson, F.5    Brady, M.6    Schnabel, J.7
  • 9
    • 84866704179 scopus 로고    scopus 로고
    • A contextual maximum likelihood framework for modeling image registration
    • C. Wachinger and N. Navab, "A contextual maximum likelihood framework for modeling image registration," Comput. Vis. Pattern Recognit., pp. 1995-2002, 2012.
    • (2012) Comput. Vis. Pattern Recognit. , pp. 1995-2002
    • Wachinger, C.1    Navab, N.2
  • 10
    • 42649114814 scopus 로고    scopus 로고
    • Using spanning graphs for efficient image registration
    • DOI 10.1109/TIP.2008.918951
    • M. Sabuncu and P. Ramadge, "Using spanning graphs for efficient image registration," IEEE Trans. Image Process., vol. 17, no. 5, pp. 788-797, May 2008. (Pubitemid 351597169)
    • (2008) IEEE Transactions on Image Processing , vol.17 , Issue.5 , pp. 788-797
    • Sabuncu, M.R.1    Ramadge, P.2
  • 11
  • 12
    • 82355181047 scopus 로고    scopus 로고
    • Cardiac motion estimation by joint alignment of tagged MRI sequences
    • E. Oubel, M. Craene, A. Hero, and A. Frangi, "Cardiac motion estimation by joint alignment of tagged MRI sequences," Med. Image Anal., vol. 16, pp. 339-350, 2012.
    • (2012) Med. Image Anal. , vol.16 , pp. 339-350
    • Oubel, E.1    Craene, M.2    Hero, A.3    Frangi, A.4
  • 13
    • 84872967460 scopus 로고    scopus 로고
    • Self-similarity weighted mutual information: A new nonrigid image registration metric
    • H. Rivaz and D. L. Collins, "Self-similarity weighted mutual information: A new nonrigid image registration metric," Proc. MICCAI, pp. 91-98, 2012.
    • (2012) Proc. MICCAI , pp. 91-98
    • Rivaz, H.1    Collins, D.L.2
  • 14
    • 0033688419 scopus 로고    scopus 로고
    • Non-rigid registration using higher-order mutual information
    • D. Rueckert, M. Clarkson, M. Hill, and D. Hawkes, "Non-rigid registration using higher-order mutual information," Proc. SPIE, pp. 438-447, 2000.
    • (2000) Proc. SPIE , pp. 438-447
    • Rueckert, D.1    Clarkson, M.2    Hill, M.3    Hawkes, D.4
  • 16
    • 84896289116 scopus 로고    scopus 로고
    • Multimodal registration via spatial-contextmutual information
    • Z.Yi and S. Soatto, "Multimodal registration via spatial-contextmutual information," Proc. Int. Conf. Inf. Process. Med. Imag. , pp. 569-580, 2007.
    • (2007) Proc. Int. Conf. Inf. Process. Med. Imag. , pp. 569-580
    • Yi, Z.1    Soatto, S.2
  • 17
    • 33646397022 scopus 로고    scopus 로고
    • Deformation-based mapping of volume change from serial brain MRI in the presence of local tissue contrast change
    • May
    • C. Studholme, C. Drapaca, B. Iordanova, and V. Cardenas, "Deformation-based mapping of volume change from serial brain MRI in the presence of local tissue contrast change," IEEE Trans. Med. Imag., vol. 25, no. 5, pp. 626-639, May 2006.
    • (2006) IEEE Trans. Med. Imag. , vol.25 , Issue.5 , pp. 626-639
    • Studholme, C.1    Drapaca, C.2    Iordanova, B.3    Cardenas, V.4
  • 18
    • 73849110555 scopus 로고    scopus 로고
    • Nonrigid image registration using conditional mutual information
    • Jan.
    • D. Loeckx, P. Slagmolen, F. Maes, D. Vandermeulen, and P. Suetens, "Nonrigid image registration using conditional mutual information," IEEE Trans. Med. Imag., vol. 29, no. 1, pp. 19-29, Jan. 2010.
    • (2010) IEEE Trans. Med. Imag. , vol.29 , Issue.1 , pp. 19-29
    • Loeckx, D.1    Slagmolen, P.2    Maes, F.3    Vandermeulen, D.4    Suetens, P.5
  • 19
    • 41449115925 scopus 로고    scopus 로고
    • Automatic segmentation of the prostate in 3D MR images by atlas matching using localized mutual information
    • DOI 10.1118/1.2842076
    • S. Klein, U. A. van der Heide, I. Lips, M. van Vulpen, M. Staring, and J. Pluim, "Automatic segmentation of the prostate in 3DMR images by atlas matching using localized mutual information," Med. Phys., vol. 35, no. 4, pp. 1407-1417, 2008. (Pubitemid 351457509)
    • (2008) Medical Physics , vol.35 , Issue.4 , pp. 1407-1417
    • Klein, S.1    Van Der Heide, U.A.2    Lips, I.M.3    Van Vulpen, M.4    Staring, M.5    Pluim, J.P.W.6
  • 20
    • 36348985858 scopus 로고    scopus 로고
    • Evaluation of optimization methods for nonrigid medical image registration using mutual information and B-splines
    • DOI 10.1109/TIP.2007.909412
    • S. Klein, M. Staring, and J. Pluim, "Evaluation of optimization methods for nonrigid medical image registration using mutual information and B-splines," IEEE Image Process., vol. 16, no. 12, pp. 2879-2890, Dec. 2007. (Pubitemid 350201222)
    • (2007) IEEE Transactions on Image Processing , vol.16 , Issue.12 , pp. 2879-2890
    • Klein, S.1    Staring, M.2    Pluim, J.P.W.3
  • 21
    • 80053494144 scopus 로고    scopus 로고
    • A nonrigid registration framework using spatially encoded mutual information and free-form deformations
    • Oct.
    • S. Zhuang, D. Arridge, D. Hawkes, and S. Ourselin, "A nonrigid registration framework using spatially encoded mutual information and free-form deformations," IEEE Trans. Med. Imag., vol. 30, no. 10, pp. 1819-1828, Oct. 2011.
    • (2011) IEEE Trans. Med. Imag. , vol.30 , Issue.10 , pp. 1819-1828
    • Zhuang, S.1    Arridge, D.2    Hawkes, D.3    Ourselin, S.4
  • 23
    • 23044477286 scopus 로고    scopus 로고
    • Automatic non-linear MRI-ultrasound registration for the correction of intra-operative brain deformations
    • DOI 10.1080/10929080500079248
    • T. Arbel, X. Morandi, R. Comeau, and D. L. Collins, "Automatic nonlinear MRI-ultrasound registration for the correction of intra-operative brain deformations," Compt. Aid. Surg., vol. 9, no. 4, pp. 123-136, 2004. (Pubitemid 41071507)
    • (2004) Computer Aided Surgery , vol.9 , Issue.4 , pp. 123-136
    • Arbel, T.1    Morandi, X.2    Comeau, R.M.3    Collins, D.L.4
  • 24
    • 84857636452 scopus 로고    scopus 로고
    • Comparing two approaches to rigid registration of three-dimensional ultrasound and magnetic resonance images for neurosurgery
    • L. Mercier, V. Fonov, C. Haegelen, R. Maesstro, K. Petrecca, and D. L. Collins, "Comparing two approaches to rigid registration of three-dimensional ultrasound and magnetic resonance images for neurosurgery," Compt. Aid. Surg., vol. 7, no. 1, pp. 125-136, 2012.
    • (2012) Compt. Aid. Surg. , vol.7 , Issue.1 , pp. 125-136
    • Mercier, L.1    Fonov, V.2    Haegelen, C.3    Maesstro, R.4    Petrecca, K.5    Collins, D.L.6
  • 26
    • 84863520771 scopus 로고    scopus 로고
    • Online database of clinical MR and ultrasound images of brain tumors
    • L. Mercier, R. Maestro, K. Petrecca, D. Araujo, C. Haegelen, and D. L. Collins, "Online database of clinical MR and ultrasound images of brain tumors," Med. Phys., vol. 39, no. 6, pp. 3253-3261, 2012.
    • (2012) Med. Phys. , vol.39 , Issue.6 , pp. 3253-3261
    • Mercier, L.1    Maestro, R.2    Petrecca, K.3    Araujo, D.4    Haegelen, C.5    Collins, D.L.6
  • 28
    • 80053484021 scopus 로고    scopus 로고
    • Simultaneous segmentation and grading of hippocampus for patient classification with Alzheimer's disease
    • P. Coupe, S. Eskildsen, J. Manjon,V. Fonov, andD. L. Collins, "Simultaneous segmentation and grading of hippocampus for patient classification with Alzheimer's disease," Proc. MICCAI, pp. 149-157, 2011.
    • (2011) Proc. MICCAI , pp. 149-157
    • Coupe, P.1    Eskildsen, S.2    Manjon, J.3    Fonov, V.4    Collins, A.L.5
  • 30
    • 0035487023 scopus 로고    scopus 로고
    • Rigid registration of 3-d ultrasound with mr images: A new approach combining intensity and gradient information
    • PII S027800620109303X
    • A. Roche, X. Pennec, G. Malandain, and N. Ayache, "Rigid registration of 3D ultrasound with MR images: A new approach combining intensity and gradient information," IEEE Trans. Med. Imag., vol. 20, no. 10, pp. 1038-1049, Oct. 2001. (Pubitemid 33777721)
    • (2001) IEEE Transactions on Medical Imaging , vol.20 , Issue.10 , pp. 1038-1049
    • Roche, A.1    Pennec, A.2    Malandain, G.3    Ayache, N.4
  • 32
    • 0348143249 scopus 로고    scopus 로고
    • Registration of freehand 3D ultrasound and magnetic resonance liver images
    • DOI 10.1016/j.media.2003.07.003
    • G. Penney, J. Blackall, M. Hamady, T. Sabharwal, A. Adam, and D. Hawkes, "Registration of freehand 3D ultrasound and magnetic resonance liver images," Med. Imag. Anal., vol. 8, no. 1, pp. 81-91, 2004. (Pubitemid 38016534)
    • (2004) Medical Image Analysis , vol.8 , Issue.1 , pp. 81-91
    • Penney, G.P.1    Blackall, J.M.2    Hamady, M.S.3    Sabharwal, T.4    Adam, A.5    Hawkes, D.J.6
  • 33
    • 52949109750 scopus 로고    scopus 로고
    • Mutual information-based image to patient re-registration using intraoperative ultrasound in image-guided neurosurgery
    • S. Ji, Z. Wu, A. Hartov, D. Roberts, and K. Paulsen, "Mutual information-based image to patient re-registration using intraoperative ultrasound in image-guided neurosurgery," Med. Phys., vol. 35, no. 10, pp. 4612-4624, 2008.
    • (2008) Med. Phys. , vol.35 , Issue.10 , pp. 4612-4624
    • Ji, S.1    Wu, Z.2    Hartov, A.3    Roberts, D.4    Paulsen, K.5
  • 34
    • 79951863239 scopus 로고    scopus 로고
    • Spatio-temporal non-rigid registration of real-time 3D echocardiography and cardiovascular MR image sequences
    • W. Zhang, M. Brady, H. Becher, and A. Noble, "Spatio-temporal non-rigid registration of real-time 3D echocardiography and cardiovascular MR image sequences," Phys. Med. Biol., vol. 56, pp. 1341-1360, 2011.
    • (2011) Phys. Med. Biol. , vol.56 , pp. 1341-1360
    • Zhang, W.1    Brady, M.2    Becher, H.3    Noble, A.4
  • 35
    • 84894610940 scopus 로고    scopus 로고
    • Towards realtime multimodal fusion for image-guided interventions using self-similarities
    • M. P. Heinrich,M. Jenkinson, B. W. Papiez, M. Brady, and J. A. Schnabel, "Towards realtime multimodal fusion for image-guided interventions using self-similarities," in Proc. MICCAI, 2013, pp. 187-194.
    • (2013) Proc. MICCAI , pp. 187-194
    • Heinrich, M.P.1    Jenkinson, M.2    Papiez, B.W.3    Brady, M.4    Schnabel, J.A.5
  • 36
    • 84885751488 scopus 로고    scopus 로고
    • Global registration of ultrasound to MRI using the LC2 metric for enabling neurosurgical guidance
    • W.Wein, A. Ladikos, B. Fuerst, A. Shah, K. Sharma, and N. Navab, "Global registration of ultrasound to MRI using the LC2 metric for enabling neurosurgical guidance," in Proc. MICCAI, 2013, pp. 34-41.
    • (2013) Proc. MICCAI , pp. 34-41
    • Wein, W.1    Ladikos, A.2    Fuerst, B.3    Shah, A.4    Sharma, K.5    Navab, N.6
  • 37
    • 79953763729 scopus 로고    scopus 로고
    • Real-time regularized ultrasound elastography
    • Apr.
    • H. Rivaz, E. Boctor, M. Choti, and G. Hager, "Real-time regularized ultrasound elastography," IEEE Trans. Med. Imag., vol. 30, no. 4, pp. 928-945, Apr. 2011.
    • (2011) IEEE Trans. Med. Imag. , vol.30 , Issue.4 , pp. 928-945
    • Rivaz, H.1    Boctor, E.2    Choti, M.3    Hager, G.4
  • 38
    • 52649109759 scopus 로고    scopus 로고
    • Ultrasound elastography: A dynamic programming approach
    • Oct.
    • H. Rivaz, E. Boctor, P. Foroughi, G. Fichtinger, and G. Hager, "Ultrasound elastography: A dynamic programming approach," IEEE Trans. Med. Imag., vol. 27, no. 10, pp. 1373-1377, Oct. 2008.
    • (2008) IEEE Trans. Med. Imag. , vol.27 , Issue.10 , pp. 1373-1377
    • Rivaz, H.1    Boctor, E.2    Foroughi, P.3    Fichtinger, G.4    Hager, G.5
  • 39
    • 0242468065 scopus 로고    scopus 로고
    • Fast parametric elastic image registration
    • Nov.
    • J. Kybic and M. Unser, "Fast parametric elastic image registration," IEEE Trans. Med. Imag., vol. 12, pp. 1427-1442, Nov. 2003.
    • (2003) IEEE Trans. Med. Imag. , vol.12 , pp. 1427-1442
    • Kybic, J.1    Unser, M.2
  • 41
    • 79551683150 scopus 로고    scopus 로고
    • Rotationally invariant similarity measures for nonlocal image denoising
    • S. Grewenig, S. Zimmer, and J. Weickert, "Rotationally invariant similarity measures for nonlocal image denoising," J. Vis. Commun. Imag. R., vol. 22, pp. 117-130, 2011.
    • (2011) J. Vis. Commun. Imag. R. , vol.22 , pp. 117-130
    • Grewenig, S.1    Zimmer, S.2    Weickert, J.3
  • 43
    • 0034313871 scopus 로고    scopus 로고
    • Earth mover's distance as a metric for image retrieval
    • DOI 10.1023/A:1026543900054
    • Y. Rubner, C. Tomasi, and L. Guibas, "The earth mover's distance as a metric for image retrieval," IEEE Trans. Pattern Anal. Mach. Int., vol. 40, no. 2, pp. 99-121, 2000. (Pubitemid 32136368)
    • (2000) International Journal of Computer Vision , vol.40 , Issue.2 , pp. 99-121
    • Rubner, Y.1    Tomasi, C.2    Guibas, L.J.3
  • 44
    • 34047206555 scopus 로고    scopus 로고
    • An efficient earth mover's distance algorithm for robust histogram comparison
    • DOI 10.1109/TPAMI.2007.1058
    • H. Ling and K. Okada, "An efficient earth mover's distance algorithm for robust histogram comparison," IEEE Trans. Pattern Anal. Mach. Int., vol. 29, no. 5, pp. 840-853, May 2007. (Pubitemid 46534780)
    • (2007) IEEE Transactions on Pattern Analysis and Machine Intelligence , vol.29 , Issue.5 , pp. 840-853
    • Ling, H.1    Okada, K.2
  • 45
    • 38849118482 scopus 로고    scopus 로고
    • Non-rigid registration of multi-modal images using both mutual information and cross-correlation
    • DOI 10.1016/j.media.2007.06.005, PII S1361841507000588
    • A. Andronache, M. V. Siebenthal, G. Szekely, and P. Cattin, "Nonrigid registration ofmulti-modal images using both mutual information and cross-correlation,"Med. Imag. Anal., vol. 12, no. 1, pp. 3-15, 2008. (Pubitemid 351189161)
    • (2008) Medical Image Analysis , vol.12 , Issue.1 , pp. 3-15
    • Andronache, A.1    Von Siebenthal, M.2    Szekely, G.3    Cattin, Ph.4
  • 47
    • 1542285823 scopus 로고    scopus 로고
    • Lucas-Kanade 20 years on: A unifying framework
    • S. Baker and I. Matthews, "Lucas-Kanade 20 years on: A unifying framework," Int. J. Comput. Vis., vol. 56, no. 3, pp. 221-255, 2004.
    • (2004) Int. J. Comput. Vis. , vol.56 , Issue.3 , pp. 221-255
    • Baker, S.1    Matthews, I.2
  • 48
    • 84875427633 scopus 로고    scopus 로고
    • Simultaneous registration of multiple images: Similarity metrics and efficient optimization
    • May
    • C. Wachinger and N. Navab, "Simultaneous registration of multiple images: Similarity metrics and efficient optimization," IEEE Trans. Pattern Anal. Mach. Intell., vol. 35, no. 5, pp. 1221-1233, May 2013.
    • (2013) IEEE Trans. Pattern Anal. Mach. Intell. , vol.35 , Issue.5 , pp. 1221-1233
    • Wachinger, C.1    Navab, N.2
  • 49
    • 84896269968 scopus 로고    scopus 로고
    • Ultrasound elastography using multiple images
    • H. Rivaz, E. M. Boctor, M. A. Choti, and G. D. Hager, "Ultrasound elastography using multiple images," Med. Image Anal. 2013 [Online]. Available: http://www.sciencedirect.com/science/article/pii/S1361841513001709
    • (2013) Med. Image Anal
    • Rivaz, H.1    Boctor, E.M.2    Choti, M.A.3    Hager, G.D.4
  • 50
    • 35148820685 scopus 로고    scopus 로고
    • A robust meshing and calibration approach for sensorless freehand 3D ultrasound
    • H. Rivaz, E. Boctor, and G. Fichtinger, "A robust meshing and calibration approach for sensorless freehand 3D ultrasound," in Proc. SPIE Med. Imag., 2007, pp. 651 318-651 326.
    • (2007) Proc. SPIE Med. Imag. , pp. 651318-651326
    • Rivaz, H.1    Boctor, E.2    Fichtinger, G.3
  • 52
    • 0031107438 scopus 로고    scopus 로고
    • Three-dimensional spatial compounding of ultrasound images
    • R. Rohling, A. Gee, and L. Berman, "Three-dimensional spatial compounding of ultrasound images," Med. Image Anal., vol. 1, no. 3, pp. 177-193, 1997. (Pubitemid 127502898)
    • (1997) Medical Image Analysis , vol.1 , Issue.3 , pp. 177-193
    • Rohling, R.1    Gee, A.2    Berman, L.3
  • 53
    • 46349104023 scopus 로고    scopus 로고
    • Beam steering approach for speckle characterization and out-of-plane motion estimation in real tissue
    • Oct.
    • H. Rivaz, R. Zellars, G. Hager, G. Fichtinger, and E. Boctor, "Beam steering approach for speckle characterization and out-of-plane motion estimation in real tissue," in IEEE Int. Ultrason. Symp., Oct. 2007, pp. 781-784.
    • (2007) IEEE Int. Ultrason. Symp. , pp. 781-784
    • Rivaz, H.1    Zellars, R.2    Hager, G.3    Fichtinger, G.4    Boctor, E.5
  • 54
    • 38849187993 scopus 로고    scopus 로고
    • Symmetric diffeomorphic image registration with cross-correlation: Evaluating automated labeling of elderly and neurodegenerative brain
    • DOI 10.1016/j.media.2007.06.004, PII S1361841507000606
    • B. Avants, C. Epstein, M. Grossman, and J. Gee, "Symmetric diffeomorphic image registration with cross-correlation: Evaluating automated labeling of elderly and neurodegenerative brain," Med. Image Anal., vol. 12, no. 1, pp. 26-41, 2008. (Pubitemid 351189163)
    • (2008) Medical Image Analysis , vol.12 , Issue.1 , pp. 26-41
    • Avants, B.B.1    Epstein, C.L.2    Grossman, M.3    Gee, J.C.4


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