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1. First-in-human technique translation of oxygen-enhanced MRI to an MR Linac system in patients with head and neck cancer

Author

Dubec, Michael J., Buckley, David L., Berks, Michael, Clough, Abigael, Gaffney, John, Datta, Anubhav, McHugh, Damien J., Porta, Nuria, Little, Ross A., Cheung, Susan, Hague, Christina, Eccles, Cynthia L., Hoskin, Peter J., Bristow, Robert G., Matthews, Julian C., van Herk, Marcel, Choudhury, Ananya, Parker, Geoff J.M., McPartlin, Andrew, and O'Connor, James P.B.

Published
2023
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2. Uncertainty analysis of MR-PET image registration for precision neuro-PET imaging

Author

Markiewicz, Pawel J., Matthews, Julian C., Ashburner, John, Cash, David M., Thomas, David L., De Vita, Enrico, Barnes, Anna, Cardoso, M. Jorge, Modat, Marc, Brown, Richard, Thielemans, Kris, da Costa-Luis, Casper, Lopes Alves, Isadora, Gispert, Juan Domingo, Schmidt, Mark E., Marsden, Paul, Hammers, Alexander, Ourselin, Sebastien, and Barkhof, Frederik

Published
2021
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5. Supplementary Figure 2 from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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6. Supplementary Video from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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7. Supplementary Figure 6 from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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8. Supplementary Figure 9 from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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9. Supplementary Figure 8 from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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10. Supplementary Tables from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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11. Supplementary Material from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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12. Supplementary Figure 4 from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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13. Supplementary Figure 7 from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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14. Supplementary Figure 11 from Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., primary, Latif, Ayşe, primary, Featherstone, Adam K., primary, Babur, Muhammad, primary, Peset, Isabel, primary, Cheung, Susan, primary, Watson, Yvonne, primary, Tessyman, Victoria, primary, Mistry, Hitesh, primary, Ashton, Garry, primary, Behan, Caron, primary, Matthews, Julian C., primary, Asselin, Marie-Claude, primary, Bristow, Robert G., primary, Jackson, Alan, primary, Parker, Geoff J.M., primary, Faivre-Finn, Corinne, primary, Williams, Kaye J., primary, and O'Connor, James P.B., primary

Published
2023
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18. sj-pdf-1-jcb-10.1177_0271678X221108841 - Supplemental material for Quantitative kinetic modelling and mapping of cerebral glucose transport and metabolism using glucoCESL MRI

Author

Dickie, Ben R, Jin, Tao, Wang, Ping, Hinz, Rainer, Harris, William, Boutin, Hervé, Parker, Geoff JM, Parkes, Laura M, and Matthews, Julian C

Subjects
110320 Radiology and Organ Imaging, FOS: Clinical medicine, FOS: Biological sciences, Medicine, Cell Biology, 110305 Emergency Medicine, 110306 Endocrinology, Biochemistry, 69999 Biological Sciences not elsewhere classified, 110904 Neurology and Neuromuscular Diseases, Neuroscience
Abstract

Supplemental material, sj-pdf-1-jcb-10.1177_0271678X221108841 for Quantitative kinetic modelling and mapping of cerebral glucose transport and metabolism using glucoCESL MRI by Ben R Dickie, Tao Jin, Ping Wang, Rainer Hinz, William Harris, Hervé Boutin, Geoff JM Parker, Laura M Parkes and Julian C Matthews in Journal of Cerebral Blood Flow & Metabolism

Published
2022
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23. Dopamine and Glutamate in Antipsychotic-Responsive compared to Antipsychotic Non-Responsive Psychosis

Author

Egerton, Alice, Murphy, Anna, Donocik, Jacek, Anton, Adriana, Barker, Gareth, Collier, Tracy, Deakin, Bill, Drake, Richard, Eliasson, Emma, Emsley, Richard, Gregory, Catherine, Griffiths, Kira, Kapur, Shitij, Kassoumeri, Laura, Knight, Laura, Emily, Lambe, Lawrie, Stephen, Lees, Jane, Lewis, Shon William, Lythgoe, David, Matthews, Julian C, Mcguire, Philip, Lily, Macnamee, Semple, Scott, Shaw, Alexander, Singh, Krish, Stockton-Powdrell, Charlotte, Talbot, Peter S, Veronese, Mattia, Wagner, Ernest, Walters, James, Williams, Stephen, Maccabe, James, and Howes, Oliver

Published
2020

28. Qualification of the Seven Dementias Platform UK PET-MR Scanners for Multicentre Trials

Author

Krokos, Georgios, primary, MacKewn, Jane, additional, Pike, Lucy, additional, Hallett, William, additional, Markiewicz, Pawel, additional, Barnes, Anna, additional, Rega, Marilena, additional, Fryer, Tim D., additional, Manavaki, Roido, additional, Anton-Rodriguez, Jose M., additional, Howell, Elizabeth, additional, Wimberley, Catriona, additional, Clark, Tim, additional, Macnaught, Gillian, additional, Marsden, Paul, additional, and Matthews, Julian C., additional

Published
2019
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30. Data‐driven mapping of hypoxia‐related tumor heterogeneity using DCE‐MRI and OE‐MRI

Author

Featherstone, Adam K., O'Connor, James P.B., Little, Ross A., Watson, Yvonne, Cheung, Sue, Babur, Muhammad, Williams, Kaye J., Matthews, Julian C., and Parker, Geoff J.M.

Subjects
Lung Neoplasms, Full Papers—Preclinical and Clinical Imaging, Normal Distribution, Mice, OE‐MRI, Carcinoma, Non-Small-Cell Lung, Neoplasms, Image Interpretation, Computer-Assisted, Image Processing, Computer-Assisted, Tumor Microenvironment, cancer, Animals, Cluster Analysis, Humans, Hypoxia, DCE‐MRI, Principal Component Analysis, Full Paper, Reproducibility of Results, Magnetic Resonance Imaging, Oxygen, Perfusion, Area Under Curve, Tumor Hypoxia, heterogeneity, Glioblastoma, Algorithms, Neoplasm Transplantation, Software, clustering
Abstract

Purpose Previous work has shown that combining dynamic contrast‐enhanced (DCE)‐MRI and oxygen‐enhanced (OE)‐MRI binary enhancement maps can identify tumor hypoxia. The current work proposes a novel, data‐driven method for mapping tissue oxygenation and perfusion heterogeneity, based on clustering DCE/OE‐MRI data. Methods DCE‐MRI and OE‐MRI were performed on nine U87 (glioblastoma) and seven Calu6 (non‐small cell lung cancer) murine xenograft tumors. Area under the curve and principal component analysis features were calculated and clustered separately using Gaussian mixture modelling. Evaluation metrics were calculated to determine the optimum feature set and cluster number. Outputs were quantitatively compared with a previous non data‐driven approach. Results The optimum method located six robustly identifiable clusters in the data, yielding tumor region maps with spatially contiguous regions in a rim‐core structure, suggesting a biological basis. Mean within‐cluster enhancement curves showed physiologically distinct, intuitive kinetics of enhancement. Regions of DCE/OE‐MRI enhancement mismatch were located, and voxel categorization agreed well with the previous non data‐driven approach (Cohen's kappa = 0.61, proportional agreement = 0.75). Conclusion The proposed method locates similar regions to the previous published method of binarization of DCE/OE‐MRI enhancement, but renders a finer segmentation of intra‐tumoral oxygenation and perfusion. This could aid in understanding the tumor microenvironment and its heterogeneity. Magn Reson Med 79:2236–2245, 2018. © 2017 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Published
2017

36. Contributors

Author

Abi-Dargham, Anissa, primary, Abrunhosa, A.J., additional, Aigner, T.G., additional, Alpert, Nathaniel M., additional, Andermann, Mark, additional, Anderson, J.R., additional, Andersson, Jesper L. R,, additional, Andreason, Paul, additional, Antonini, A., additional, Arai, Hiroyuki, additional, Ardekani, B.A., additional, Ashburner, John, additional, Ashworth, S., additional, Bailey, D.L., additional, Bánáti, Richard B., additional, Baron, J.C., additional, Barrio, Jorge R., additional, Bauer, R., additional, Beattie, Bradley J., additional, Bergmann, R., additional, Berman, Karen Faith, additional, Berzdorf, A., additional, Besret, L., additional, Blasberg, Ronald G., additional, Bloomfìeld, P.M., additional, Bonab, Ali A., additional, Bowery, A., additional, Brady, F., additional, Brooks, David J., additional, Brühlmeier, M., additional, Brust, P., additional, Budinger, T.F., additional, Byrne, Helen, additional, Carson, Richard E., additional, Chan, G.L. Y., additional, Chatziioannou, Arion, additional, Chefer, Svetlana I., additional, Chen, Chin-Tu, additional, Cherry, Simon R., additional, Cheung, K., additional, Chugani, Diane C., additional, Chugani, Harry T., additional, Cooper, Malcolm, additional, Cunningham, Vincent J., additional, Dagher, Alain, additional, Dahlbom, M., additional, Danielsen, E.H., additional, DaSilva, J.N., additional, Davis, James, additional, de Lima, J.J., additional, DeJesus, O.T., additional, Derenzo, S.E., additional, Dhawan, V., additional, Dogan, A.S., additional, Doudet, D.J., additional, Drevets, W., additional, Duncan, John, additional, Eidelberg, D., additional, Ellmore, Timothy M., additional, Endres, Christopher J., additional, English, C., additional, Esposito, Giuseppe, additional, Evans, Alan C., additional, Farahani, K., additional, Feng, Dagan, additional, Ficaro, Edward P., additional, Fischer, N., additional, Fischman, Alan J., additional, Fiset, Pierre, additional, Frey, Kirk A., additional, Friston, K.J., additional, Füchtner, F., additional, Fukushi, K., additional, Gee, A.D., additional, Ghaemi, M., additional, Ghez, C., additional, Ghilardi, M.F., additional, Gillispie, Steven B., additional, Gjedde, Albert, additional, Graf, R., additional, Grafton, Scott T., additional, Graham, Michael M., additional, Grasby, Paul M., additional, Greenwald, E., additional, Gunn, Roger N., additional, Günther, I., additional, Hansen, L.K., additional, Hansen, Søren B., additional, Heiss, W.-D., additional, Herholz, K., additional, Higuchi, Makoto, additional, Hirani, E., additional, Ho, D., additional, Hoffman, John M., additional, Holden, J.E., additional, Holt, Daniel, additional, Holt, John L., additional, Hommer, Daniel W., additional, Horwitz, Barry, additional, Houle, Sylvain, additional, Huang, Sung-Cheng, additional, Huang, Yiyun, additional, Huesman, R.H., additional, Hume, S.P., additional, Hussey, D., additional, Ibazizene, M., additional, Ido, Tatsuo, additional, Ilmberger, J., additional, Inaba, T., additional, Innis, Robert B., additional, Irie, T., additional, Ishii, Kenji, additional, Ito, K., additional, Itoh, Masatoshi, additional, Iyo, M., additional, Jivan, S., additional, Johannsen, B., additional, Johannsen, Peter, additional, Jones, Terry, additional, Kanno, Iwao, additional, Kapur, S., additional, Kawashima, Ryuta, additional, Kazumata, K., additional, Kilbourn, Michael R., additional, Klein, Denise, additional, Klein, G.J., additional, Koepp, Matthias, additional, Koeppe, Robert A., additional, Kuhl, David E., additional, Kumura, E., additional, Künig, G., additional, Labbé, Claire, additional, Lammertsma, Adriaan A., additional, Landeau, B., additional, Lange, N., additional, Larson, Steve M., additional, Laruelle, Marc, additional, Lau, K.K., additional, Law, I., additional, Leenders, K.L., additional, Lin, K.P., additional, Litt, Harold, additional, Livieratos, L., additional, Lockwood, Geoff, additional, London, Edythe D., additional, Lopresti, Brian, additional, Löttgen, J., additional, Luthra, S.K., additional, Ma, Yilong, additional, MacLeod, A.M., additional, Marenco, S., additional, Marrett, S., additional, Mason, N. Scott, additional, Mathis, Chester A., additional, Matthews, Julian C., additional, Mawlawi, Osama R., additional, Meadors, Ken, additional, Meikle, S.R., additional, Meyer, Ernst, additional, Miller, David H., additional, Miller, M.P., additional, Minoshima, Satoshi, additional, Missimer, J., additional, Moeller, J.R., additional, Moore, A.H., additional, Moran, L., additional, Moreno-Cantú, Jorge J., additional, Morris, Evan D., additional, Morris, H., additional, Morrish, P.K., additional, Morrison, K.S., additional, Moses, W.W., additional, Muzi, Mark, additional, Muzik, Otto, additional, Myers, Ralph, additional, Nagatsuka, S., additional, Namba, H., additional, Nguyen, Thinh B., additional, O'Sullivan, Finbarr, additional, Oakes, T.R., additional, Oda, Keiichi, additional, Ohta, K., additional, Okamura, Nobuyuki, additional, Opacka-Juffry, J., additional, Osman, S., additional, Østergaard, Leif, additional, Paulesu, Eraldo, additional, Paulson, O.B., additional, Paus, T., additional, Pawlik, G., additional, Perevuznik, Jennifer, additional, Petit-Taboué, M.C., additional, Phelps, Michael E., additional, Pietrzyk, U., additional, Price, Julie C., additional, Price, Pat M., additional, Psylla, M., additional, Raffel, D.M., additional, Rakshi, J.S., additional, Raleigh, Michael J., additional, Rawlings, Robert R., additional, Rehm, K., additional, Reulen, H. -J., additional, Reutens, David C., additional, Reutter, B.W., additional, Richardson, Mark, additional, Rio, Daniel, additional, Rottenberg, D.A., additional, Rousset, Olivier G., additional, Ruszkiewicz, James, additional, Ruth, T.J., additional, Ruttimann, Urs E., additional, Sadato, Norihiro, additional, Sasaki, Hidetada, additional, Schaper, K.A., additional, Schumann, P., additional, Schuster, A., additional, Senda, Michio, additional, Shao, Yiping, additional, Shen, Chenggang, additional, Shinotoh, H., additional, Silverman, Robert W., additional, Simpson, N.R., additional, Siu, Wan-Chi, additional, Slates, R., additional, Smith, D.F., additional, Smith, Gwenn S., additional, Snyder, Scott E., additional, Sobesky, J., additional, Søiling, Thomas, additional, Sossi, V., additional, Spinks, Terry J., additional, Steinbach, J., additional, Stout, David B., additional, Strother, S.C., additional, Sudo, Y., additional, Sugita, M., additional, Suhara, T., additional, Suzuki, K., additional, Tatsumi, Itaru, additional, Teng, X., additional, Thiel, A., additional, Thompson, Christopher J., additional, Thorpe, John, additional, Toussaint, P.-J., additional, Toyama, Hinako, additional, Uema, T., additional, Vafaee, M.S., additional, Van Horn, John Darrell, additional, Venkatachalam, T.K., additional, Virador, P.R.G., additional, von Stockhausen, H.-M., additional, Vontobel, P., additional, Vorwieger, G., additional, Votaw, John R., additional, Walter, B., additional, Wienhard, K., additional, Wilson, A.A., additional, Wong, Dean F., additional, Wong, Koon-Pong, additional, Wu, Chi-Ming, additional, Wu, L.C., additional, Yamaki, Atsushi, additional, Yanai, Kazuhiko, additional, Yang, J., additional, Yap, Jeffrey T., additional, Yokoi, Fuji, additional, Young, A.R., additional, Yu, C.L., additional, and Zatorre, Robert J., additional

Published
1998
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39. Data-driven mapping of hypoxia-related tumor heterogeneity using DCE-MRI and OE-MRI

Author

Featherstone, Adam K., O'Connor, James P.B., Little, Ross A., Watson, Yvonne, Cheung, Sue, Babur, Muhammad, Williams, Kaye J., Matthews, Julian C., and Parker, Geoff J.M.

Subjects
DCE-MRI, hypoxia, Radiology Nuclear Medicine and imaging, cancer, heterogeneity, OE-MRI, clustering
Abstract

Purpose: Previous work has shown that combining dynamic contrast-enhanced (DCE)-MRI and oxygen-enhanced (OE)-MRI binary enhancement maps can identify tumor hypoxia. The current work proposes a novel, data-driven method for mapping tissue oxygenation and perfusion heterogeneity, based on clustering DCE/OE-MRI data. Methods: DCE-MRI and OE-MRI were performed on nine U87 (glioblastoma) and seven Calu6 (non-small cell lung cancer) murine xenograft tumors. Area under the curve and principal component analysis features were calculated and clustered separately using Gaussian mixture modelling. Evaluation metrics were calculated to determine the optimum feature set and cluster number. Outputs were quantitatively compared with a previous non data-driven approach. Results: The optimum method located six robustly identifiable clusters in the data, yielding tumor region maps with spatially contiguous regions in a rim-core structure, suggesting a biological basis. Mean within-cluster enhancement curves showed physiologically distinct, intuitive kinetics of enhancement. Regions of DCE/OE-MRI enhancement mismatch were located, and voxel categorization agreed well with the previous non data-driven approach (Cohen's kappa = 0.61, proportional agreement = 0.75). Conclusion: The proposed method locates similar regions to the previous published method of binarization of DCE/OE-MRI enhancement, but renders a finer segmentation of intra-tumoral oxygenation and perfusion. This could aid in understanding the tumor microenvironment and its heterogeneity. Magn Reson Med 79:2236–2245, 2018.

Published
2018

40. Oxygen-enhanced MRI Is Feasible, Repeatable, and Detects Radiotherapy-induced Change in Hypoxia in Xenograft Models and in Patients with Non–small Cell Lung Cancer

Author

Salem, Ahmed, primary, Little, Ross A., additional, Latif, Ayşe, additional, Featherstone, Adam K., additional, Babur, Muhammad, additional, Peset, Isabel, additional, Cheung, Susan, additional, Watson, Yvonne, additional, Tessyman, Victoria, additional, Mistry, Hitesh, additional, Ashton, Garry, additional, Behan, Caron, additional, Matthews, Julian C., additional, Asselin, Marie-Claude, additional, Bristow, Robert G., additional, Jackson, Alan, additional, Parker, Geoff J.M., additional, Faivre-Finn, Corinne, additional, Williams, Kaye J., additional, and O'Connor, James P.B., additional

Published
2019
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43. Motion-corrected reconstruction of parametric images from dynamic PET data with the Synergistic Image Reconstruction Framework (SIRF)

Author

Brown, Richard, primary, Thomas, Benjamin A., additional, Rashidnasab, Alaleh, additional, Erlandsson, Kjell, additional, Ovtchinnikov, Evgueni, additional, Pasca, Edoardo, additional, Reader, Andrew, additional, Matthews, Julian C., additional, Tsoumpas, Charalampos, additional, and Thielemans, Kris, additional

Published
2018
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44. In vivo imaging of brain microglial activity in antipsychotic-free and medicated schizophrenia: a [11C](R)-PK11195 positron emission tomography study

Author

Holmes, Sophie E, Hinz, Rainer, Drake, Richard J, Gregory, Catherine J, Conen, Silke, Matthews, Julian C, Anton-Rodriguez, Jose M, Gerhard, Alexander, and Talbot, Peter S

Abstract

Positron emission tomography (PET) imaging of the 18 kDa translocator protein (TSPO) has been used to investigate whether microglial activation, an indication of neuroinflammation, is evident in the brain of adults with schizophrenia. Interpretation of these studies is confounded by potential modulatory effects of antipsychotic medication on microglial activity. In the first such study in antipsychotic-free schizophrenia, we have used [11C](R)-PK11195 PET to compare TSPO availability in a predominantly antipsychotic-naive group of moderate-to-severely symptomatic unmedicated patients (n=8), similarly symptomatic medicated patients with schizophrenia taking risperidone or paliperidone by regular intramuscular injection (n=8), and healthy comparison subjects (n=16). We found no evidence for increased TSPO availability in antipsychotic-free patients compared with healthy controls (mean difference 4%, P=0.981). However, TSPO availability was significantly elevated in medicated patients (mean increase 88%, P=0.032) across prefrontal (dorsolateral, ventrolateral, orbital), anterior cingulate and parietal cortical regions. In the patients, TSPO availability was also strongly correlated with negative symptoms measured using the Positive and Negative Syndrome Scale across all the brain regions investigated (r=0.651-0.741). We conclude that the pathophysiology of schizophrenia is not associated with microglial activation in the 2-6 year period following diagnosis. The elevation in the medicated patients may be a direct effect of the antipsychotic, although this study cannot exclude treatment resistance and/or longer illness duration as potential explanations. It also remains to be determined whether it is present only in a subset of patients, represents a pro- or anti-inflammatory state, its association with primary negative symptoms, and whether there are significant differences between antipsychotics.

Published
2016

49. Acute and chronic changes in brain activity with deep brain stimulation for refractory depression.

Author

Conen, Silke, Matthews, Julian C., Patel, Nikunj K., Anton-Rodriguez, José, and Talbot, Peter S.

Subjects
*DEEP brain stimulation, *DEPRESSED persons, *CEREBRAL circulation, *POSITRON emission tomography, *PREFRONTAL cortex, *BASAL ganglia, *COMPARATIVE studies, *MENTAL depression, *FRONTAL lobe, *RESEARCH methodology, *MEDICAL cooperation, *PSYCHOLOGICAL tests, *RESEARCH, *EVALUATION research
Abstract

Deep brain stimulation is a potential option for patients with treatment-refractory depression. Deep brain stimulation benefits have been reported when targeting either the subgenual cingulate or ventral anterior capsule/nucleus accumbens. However, not all patients respond and optimum stimulation-site is uncertain. We compared deep brain stimulation of the subgenual cingulate and ventral anterior capsule/nucleus accumbens separately and combined in the same seven treatment-refractory depression patients, and investigated regional cerebral blood flow changes associated with acute and chronic deep brain stimulation. Deep brain stimulation-response was defined as reduction in Montgomery-Asberg Depression Rating Scale score from baseline of ≥50%, and remission as a Montgomery-Asberg Depression Rating Scale score ≤8. Changes in regional cerebral blood flow were assessed using [15O]water positron emission tomography. Remitters had higher relative regional cerebral blood flow in the prefrontal cortex at baseline and all subsequent time-points compared to non-remitters and non-responders, with prefrontal cortex regional cerebral blood flow generally increasing with chronic deep brain stimulation. These effects were consistent regardless of stimulation-site. Overall, no significant regional cerebral blood flow changes were apparent when deep brain stimulation was acutely interrupted. Deep brain stimulation improved treatment-refractory depression severity in the majority of patients, with consistent changes in local and distant brain regions regardless of target stimulation. Remission of depression was reached in patients with higher baseline prefrontal regional cerebral blood flow. Because of the small sample size these results are preliminary and further evaluation is necessary to determine whether prefrontal cortex regional cerebral blood flow could be a predictive biomarker of treatment response. [ABSTRACT FROM AUTHOR]

Published
2018
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50. Direct parametric reconstruction for dynamic [18F]-FDG PET/CT imaging in the body

Author

Kotasidis Fotis A., Matthews Julian C., Reader Andrew J., Angelis Georgios I., Price Pat Mary, and Zaidi Habib

Abstract

Abdominal and thoracic [18F]FDG PET/CT imaging is routinely used in clinical practice and drug development but parametric imaging based on full kinetic analysis is rarely used due to noise induced bias and variance in kinetic parameters and analysis is usually restricted to semi quantitative indices. Direct parametric estimation using 4D image reconstruction can potentially provide parametric maps of reduced bias and variance but little or no evaluation has been done in the body. Previous studies have demonstrated that body [18F]FDG PET/CT imaging can benefit from these methods but analysis was restricted to macroparameters of interest. In work we implement and apply a recently proposed direct 4 D algorithm using a 2 tissue compartment model on simulated and real oncology [18F]FDG PET/CT data to directly estimate microparameters of interest and assess potential improvements over the traditional post reconstruction kinetic analysis. Results on the simulated data suggest clear reduction in bias for K1 k2 and blood volume and less for k3. Similarly variance reduction was observed for K1 k2 k3 and Ki and less for blood volume. Evaluation on patient data demonstrated similar improvements using the direct 4 D method in agreement with simulations. © 2012 IEEE.

Published
2012
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