Dr Ricky O'Brien

Associate Professor, Principal Research Fellow
Central Clinical School


Map

Biographical details

I am the deputy director of the ACRF Image X Institute at the University of Sydney (http://sydney.edu.au/medicine/image-x). My primary research interest is in developing new medical imaging techniques with a focus in radiotherapy. This work is cross disciplinary and covers novel applications in medicine, physics, mathematics, computer science and engineering. As such, I offer Ph.D. and honours projects to students from a range of disciplines such as medical physics, mathematics and engineering who want to work on projects that will improve human health.

Research interests

I develop patient connected imaging techniques where I use biofeedback to improve image acquistion. For example, we use feedback from respiratory and cardiac sensors to adapt and change the imaging hardware during acqusition in both radiotherapy and radiology. By doing this we can eliminate the blurring of organs and tumours that result when the tumour/organ move while we breathe or our heart beats.

Current research students

Project title Research student
On the optimisation of imaging dose in four dimensional cone-beam computed tomography for radiation oncology patients Ben COOPER
Improving thoracic imaging and tumor localisation for lung cancer radiotherapy: world-first implementation of Respiratory Adaptive CT Natasha MORTON

Current projects

My projects are multidisciplinary and we collaborate and offer PhD, Masters and Honours projects to a wide range of disciplines. Specifically, we have projects encompassing:

  • Mathematical optimisation to optimise 4DCBCT image acquisition and radiotherapy treatment planning.
  • Engineering to build and design new medical devices and phantoms (The Australian MRI-Linac program and the Nano-X miniature linear accelerator).
  • Engineering for image processing and real-time hardware control.
  • Medical physics for patient treatment and clincial trials.
  • Computer science for real-time control systems.

Examples of current projects and clincial trials within the ACRF Image X Institute at the University of Sydney, include:

  • Improving 4DCBCT imaging (http://sydney.edu.au/medicine/image-x/research/4D-CBCT-imaging.php).
  • The Australian MRI Linac Program (http://sydney.edu.au/medicine/image-x/research/MRI-linac-program.php).
  • The Nano-X linear accelerator (http://sydney.edu.au/medicine/image-x/research/nano-x.php)
  • Real-time tumour tracking (http://sydney.edu.au/medicine/image-x/research/realtime-tumour-tracking.php).
  • Kilovoltage Intrafraction Monitoring (http://sydney.edu.au/medicine/image-x/research/KIM.php).

Selected grants

2018

  • Very fast, accurate and low dose imaging for radiotherapy treatments; O'Brien R, Sonke J, Vinod S, Froyland G, Shieh C; National Health and Medical Research Council (NHMRC)/Project Grants.
  • The Clincial Translation of NSW Invented Tumour Motion Management Technologies in Cancer Radiotherapy; O'Brien R, Keall P; Cancer Institute NSW/Career Development Fellowship.

2017

  • Nano-X: A new class of cancer radiotherapy system; Keall P, Liu P, Mackie T, Prather P, O'Brien R, Jackson M, Barton M, Bennett P, Thwaites D, Booth J, Crossing S, Baxi S, Downes S; National Health and Medical Research Council (NHMRC)/Development Grants.

2015

  • Reducing Thoracic Imaging Dose and Improving Image Quality in Radiation Therapy; O'Brien R, Froyland G, Sonke J; Cancer Australia/Priority Driven Collaborative Cancer Research Scheme.

Selected publications

Download citations: PDF RTF Endnote

Journals

  • Nguyen, D., Booth, J., Caillet, V., Hardcastle, N., Briggs, A., Haddad, C., Eade, T., O'Brien, R., Keall, P. (2018). An augmented correlation framework for the estimation of tumour translational and rotational motion during external beam radiotherapy treatments using intermittent monoscopic X-ray imaging and an external respiratory signal. Physics in Medicine and Biology, 63(20), 1-17. [More Information]
  • Martin, S., O'Brien, R., Hofmann, C., Keall, P., Kipritidis, J. (2018). An in silico performance characterization of respiratory motion guided 4DCT for high-quality low-dose lung cancer imaging. Physics in Medicine and Biology, 63, 1-15. [More Information]
  • Nguyen, D., Bertholet, J., Kim, J., O'Brien, R., Booth, J., Poulsen, P., Keall, P. (2018). An interdimensional correlation framework for real-time estimation of six degree of freedom target motion using a single x-ray imager during radiotherapy. Physics in Medicine and Biology, 63(1), 1-15. [More Information]
  • Keall, P., Colvill, E., O'Brien, R., Caillet, V., Eade, T., Kneebone, A., Hruby, G., Poulsen, P., Zwan, B., Greer, P., Booth, J. (2018). Electromagnetic-Guided MLC Tracking Radiation Therapy for Prostate Cancer Patients: Prospective Clinical Trial Results. International Journal of Radiation Oncology Biology Physics, 101(2), 387-395. [More Information]
  • Pollock, S., Tse, R., Martin, D., McLean, L., Pham, M., Tait, D., Estoesta, R., Whittington, G., Turley, J., Kearney, C., Hill, R., Makhija, K., O'Brien, R., Keall, P., et al (2018). Impact of audiovisual biofeedback on interfraction respiratory motion reproducibility in liver cancer stereotactic body radiotherapy. Journal of Medical Imaging and Radiation Oncology, 62(1), 133-139. [More Information]
  • Lydiard, S., Caillet, V., Ipsen, S., O'Brien, R., Blanck, O., Poulsen, P., Booth, J., Keall, P. (2018). Investigating multi-leaf collimator tracking in stereotactic arrhythmic radioablation (STAR) treatments for atrial fibrillation. Physics in Medicine and Biology, 63(19), 1-13. [More Information]
  • Toftegaard, J., Keall, P., O'Brien, R., Ruan, D., Ernst, F., Homma, N., Ichiji, K., Poulsen, P. (2018). Potential improvements of lung and prostate MLC tracking investigated by treatment simulations. Medical Physics, 45(5), 2218-2229. [More Information]
  • Keall, P., Nguyen, D., O'Brien, R., Zhang, P., Happersett, L., Bertholet, J., Poulsen, P. (2018). Review of Real-Time 3-Dimensional Image Guided Radiation Therapy on Standard-Equipped Cancer Radiation Therapy Systems: Are We at the Tipping Point for the Era of Real-Time Radiation Therapy? International Journal of Radiation Oncology Biology Physics, 102(4), 922-931. [More Information]
  • Liu, P., Nguyen, D., Feain, L., O'Brien, R., Keall, P., Booth, J. (2018). Technical note: Real-time image-guided adaptive radiotherapy of a rigid target for a prototype fixed beam radiotherapy system. Medical Physics, 45(10), 4660-4666. [More Information]
  • Kim, J., Nguyen, D., Booth, J., Huang, C., Fuangrod, T., Poulsen, P., O'Brien, R., Caillet, V., Eade, T., Kneebone, A., Keall, P. (2018). The accuracy and precision of Kilovoltage Intrafraction Monitoring (KIM) six degree-of-freedom prostate motion measurements during patient treatments. Radiotherapy and Oncology, 126(2), 236-243. [More Information]
  • Keall, P., Nguyen, D., O'Brien, R., Caillet, V., Hewson, E., Poulsen, P., Bromley, R., Bell, L., Eade, T., Kneebone, A., Booth, J., et al (2018). The first clinical implementation of real-time image-guided adaptive radiotherapy using a standard linear accelerator. Radiotherapy and Oncology, 127(1), 6-11. [More Information]
  • Lee, D., Greer, P., Lapuz, C., Ludbrook, J., Hunter, P., Arm, J., Pollock, S., Makhija, K., O'Brien, R., Kim, T., Keall, P. (2017). Audiovisual biofeedback guided breath-hold improves lung tumor position reproducibility and volume consistency. Advances in Radiation Oncology, 2(3), 354-362. [More Information]
  • Caillet, V., Keall, P., Colvill, E., Hardcastle, N., O'Brien, R., Szymura, K., Booth, J. (2017). MLC tracking for lung SABR reduces planning target volumes and dose to organs at risk. Radiotherapy and Oncology, 124(1), 18-24. [More Information]
  • Kim, J., Nguyen, D., Huang, C., Fuangrod, T., Caillet, V., O'Brien, R., Poulsen, P., Booth, J., Keall, P. (2017). Quantifying the accuracy and precision of a novel real-time 6 degree-of-freedom kilovoltage intrafraction monitoring (KIM) target tracking system. Physics in Medicine and Biology, 62(14), 5744-5759. [More Information]
  • O'Brien, R., Stankovic, U., Sonke, J., Keall, P. (2017). Reducing 4DCBCT imaging time and dose: The first implementation of variable gantry speed 4DCBCT on a linear accelerator. Physics in Medicine and Biology, 62(11), 4300-4317. [More Information]
  • Keall, P., Nguyen, D., O'Brien, R., Booth, J., Greer, P., Poulsen, P., Gebski, V., Kneebone, A., Martin, J. (2017). Stereotactic prostate adaptive radiotherapy utilising kilovoltage intrafraction monitoring: The TROG 15.01 SPARK trial. BMC Cancer, 17(1), 1-7. [More Information]
  • Feain, I., Coleman, L., Wallis, H., Sokolov, R., O'Brien, R., Keall, P. (2017). Technical Note: The design and function of a horizontal patient rotation system for the purposes of fixed-beam cancer radiotherapy. Medical Physics, 44(6), 2490-2502. [More Information]
  • Nguyen, D., O'Brien, R., Kim, J., Huang, C., Wilton, L., Greer, P., Legge, K., Booth, J., Poulsen, P., Martin, J., Keall, P. (2017). The first clinical implementation of a real-time six degree of freedom target tracking system during radiation therapy based on Kilovoltage Intrafraction Monitoring (KIM). Radiotherapy and Oncology, 123(1), 37-42. [More Information]
  • Lee, D., Greer, P., Ludbrook, J., Arm, J., Hunter, P., Pollock, S., Makhija, K., O'Brien, R., Kim, T., Keall, P. (2016). Audiovisual Biofeedback Improves Cine-Magnetic Resonance Imaging Measured Lung Tumor Motion Consistency. International Journal of Radiation Oncology Biology Physics, 94(3), 628-636. [More Information]
  • Feain, I., Shieh, C., White, P., O'Brien, R., Fisher, S., Counter, W., Lazarakis, P., Stewart, D., Downes, S., Jackson, M., Whelan, B., Makhija, K., Huang, C., Keall, P., et al (2016). Functional imaging equivalence and proof of concept for image-guided adaptive radiotherapy with fixed gantry and rotating couch. Advances in Radiation Oncology, 1(4), 365-372. [More Information]
  • Ipsen, S., Bruder, R., O'Brien, R., Keall, P., Schweikard, A., Poulsen, P. (2016). Online 4D ultrasound guidance for real-time motion compensation by MLC tracking. Medical Physics, 43(10), 5695-5704. [More Information]
  • Keall, P., Ng, J., Juneja, P., O'Brien, R., Huang, C., Colvill, E., Caillet, V., Simpson, E., Poulsen, P., Kneebone, A., Eade, T., Booth, J. (2016). Real-Time 3D Image Guidance Using a Standard LINAC: Measured Motion, Accuracy, and Precision of the First Prospective Clinical Trial of Kilovoltage Intrafraction Monitoringe-Guided Gating for Prostate Cancer Radiation Therapy. International Journal of Radiation Oncology Biology Physics, 94(5), 1015-1021. [More Information]
  • Wisotzky, E., O'Brien, R., Keall, P. (2016). Technical Note: A novel leaf sequencing optimization algorithm which considers previous underdose and overdose events for MLC tracking radiotherapy. Medical Physics, 43(1), 132-136. [More Information]
  • O'Brien, R., Cooper, B., Shieh, C., Stankovic, U., Keall, P., Sonke, J. (2016). The first implementation of respiratory triggered 4DCBCT on a linear accelerator. Physics in Medicine and Biology, 61(9), 3488-3499. [More Information]
  • Booth, J., Caillet, V., Hardcastle, N., O'Brien, R., Szymura, K., Crasta, C., Harris, B., Haddad, C., Eade, T., Keall, P. (2016). The first patient treatment of electromagnetic-guided real time adaptive radiotherapy using MLC tracking for lung SABR. Radiotherapy and Oncology, 121(1), 19-25. [More Information]
  • Pollock, S., O'Brien, R., Makhija, K., Hegi-Johnson, F., Ludbrook, J., Rezo, A., Tse, R., Eade, T., Yeghiaian-Alvandi, R., Gebski, V., Keall, P. (2015). Audiovisual biofeedback breathing guidance for lung cancer patients receiving radiotherapy: A multi-institutional phase II randomised clinical trial. BMC Cancer, 15(1), 1-8. [More Information]
  • Wallace, D., Ng, J., Keall, P., O'Brien, R., Poulsen, P., Juneja, P., Booth, J. (2015). Determining appropriate imaging parameters for kilovoltage intrafraction monitoring: an experimental phantom study. Physics in Medicine and Biology, 60(12), 4835-4847. [More Information]
  • Pollock, S., Tse, R., Martin, D., McLean, L., Cho, G., Hill, R., Pickard, S., Aston, P., Huang, C., Makhija, K., O'Brien, R., Keall, P. (2015). First clinical implementation of audiovisual biofeedback in liver cancer stereotactic body radiation therapy. Journal of Medical Imaging and Radiation Oncology, 59(5), 654-656. [More Information]
  • Shieh, C., Kipritidis, J., O'Brien, R., Cooper, B., Kuncic, Z., Keall, P. (2015). Improving thoracic four-dimensional cone-beam CT reconstruction with anatomical-adaptive image regularization (AAIR). Physics in Medicine and Biology, 60(2), 841-868. [More Information]
  • Colvill, E., Booth, J., O'Brien, R., Eade, T., Kneebone, A., Poulsen, P., Keall, P. (2015). Multileaf Collimator Tracking Improves Dose Delivery for Prostate Cancer Radiation Therapy: Results of the First Clinical Trial. International Journal of Radiation Oncology Biology Physics, 92(5), 1141-1147. [More Information]
  • Cooper, B., O'Brien, R., Kipritidis, J., Shieh, C., Keall, P. (2015). Quantifying the image quality and dose reduction of respiratory triggered 4D cone-beam computed tomography with patient-measured breathing. Physics in Medicine and Biology, 60(24), 9493-9513. [More Information]
  • Keall, P., Ng, J., O'Brien, R., Colvill, E., Huang, C., Poulsen, P., Flederlius, W., Juneja, P., Simpson, E., Bell, L., Booth, J., et al (2015). The first clinical treatment with kilovoltage intrafraction monitoring (KIM): A real-time image guidance method. Medical Physics, 42(1), 354-358. [More Information]
  • Colvill, E., Poulsen, P., Booth, J., O'Brien, R., Ng, J., Keall, P. (2014). DMLC tracking and gating can improve dose coverage for prostate VMAT. Medical Physics, 41(9), 1-10. [More Information]
  • Shieh, C., Kipritidis, J., O'Brien, R., Kuncic, Z., Keall, P. (2014). Image quality in thoracic 4D cone-beam CT: a sensitivity analysis of respiratory signal, binning method, reconstruction algorithm, and projection angular spacing. Medical Physics, 41(4), 041912-1-041912-18. [More Information]
  • O'Brien, R., Kipritidis, J., Shieh, C., Keall, P. (2014). Optimizing 4DCBCT projection allocation to respiratory bins. Physics in Medicine and Biology, 59(19), 5631-5649. [More Information]
  • Ng, J., Booth, J., O'Brien, R., Colvill, E., Huang, C., Poulsen, P., Keall, P. (2014). Quality assurance for the clinical implementation of kilovoltage intrafraction monitoring for prostate cancer VMAT. Medical Physics, 41(11), 111712-1-111712-9. [More Information]
  • O'Brien, R., Cooper, B., Kipritidis, J., Shieh, C., Keall, P. (2014). Respiratory motion guided four dimensional cone beam computed tomography: Encompassing irregular breathing. Physics in Medicine and Biology, 59(3), 579-595. [More Information]
  • Keall, P., Colvill, E., O'Brien, R., Ng, J., Poulsen, P., Eade, T., Kneebone, A., Booth, J. (2014). The first clinical implementation of electromagnetic transponder-guided MLC tracking. Medical Physics, 41(2), 020702-1-020702-5. [More Information]
  • Ge, Y., O'Brien, R., Shieh, C., Booth, J., Keall, P. (2014). Toward the development of intrafraction tumor deformation tracking using a dynamic multi-leaf collimator. Medical Physics, 41(6), 061703-1-061703-10. [More Information]
  • Pommer, T., Falk, M., Poulsen, P., Keall, P., O'Brien, R., Petersen, P., af Rosenschold, P. (2013). Dosimetric benefit of DMLC tracking for conventional and sub-volume boosted prostate intensity-modulated arc radiotherapy. Physics in Medicine and Biology, 58(7), 2349-2361. [More Information]
  • O'Brien, R., Cooper, B., Keall, P. (2013). Optimizing 4D cone beam computed tomography acquisition by varying the gantry velocity and projection time interval. Physics in Medicine and Biology, 58(6), 1705-1723. [More Information]
  • Nasehi Tehrani, J., O'Brien, R., Poulsen, P., Keall, P. (2013). Real-time estimation of prostate tumor rotation and translation with a kV imaging system based on an iterative closest point algorithm. Physics in Medicine and Biology, 58(23), 8517-8533. [More Information]
  • Cooper, B., O'Brien, R., Balik, S., Hugo, G., Keall, P. (2013). Respiratory triggered 4D cone-beam computed tomography: A novel method to reduce imaging dose. Medical Physics, 40(4), 041901-1-041901-9. [More Information]
  • Pommer, T., Falk, M., Poulsen, P., Keall, P., O'Brien, R., af Rosenschold, P. (2013). The impact of leaf width and plan complexity on DMLC tracking of prostate intensity modulated arc therapy. Medical Physics, 40(11), 111717-1-111717-6. [More Information]
  • Kim, T., Pollock, S., Lee, D., O'Brien, R., Keall, P. (2012). Audiovisual biofeedback improves diaphragm motion reproducibility in MRI. Medical Physics, 39(11), 6921-6928. [More Information]

Patents

  • Keall, P., O'Brien, R., Cooper, B., Lu, J., Williamson, J. (2016). Optimising RMG-4DCBCT Image Acquisition. Patent No. 201280037958. China.

2018

  • Nguyen, D., Booth, J., Caillet, V., Hardcastle, N., Briggs, A., Haddad, C., Eade, T., O'Brien, R., Keall, P. (2018). An augmented correlation framework for the estimation of tumour translational and rotational motion during external beam radiotherapy treatments using intermittent monoscopic X-ray imaging and an external respiratory signal. Physics in Medicine and Biology, 63(20), 1-17. [More Information]
  • Martin, S., O'Brien, R., Hofmann, C., Keall, P., Kipritidis, J. (2018). An in silico performance characterization of respiratory motion guided 4DCT for high-quality low-dose lung cancer imaging. Physics in Medicine and Biology, 63, 1-15. [More Information]
  • Nguyen, D., Bertholet, J., Kim, J., O'Brien, R., Booth, J., Poulsen, P., Keall, P. (2018). An interdimensional correlation framework for real-time estimation of six degree of freedom target motion using a single x-ray imager during radiotherapy. Physics in Medicine and Biology, 63(1), 1-15. [More Information]
  • Keall, P., Colvill, E., O'Brien, R., Caillet, V., Eade, T., Kneebone, A., Hruby, G., Poulsen, P., Zwan, B., Greer, P., Booth, J. (2018). Electromagnetic-Guided MLC Tracking Radiation Therapy for Prostate Cancer Patients: Prospective Clinical Trial Results. International Journal of Radiation Oncology Biology Physics, 101(2), 387-395. [More Information]
  • Pollock, S., Tse, R., Martin, D., McLean, L., Pham, M., Tait, D., Estoesta, R., Whittington, G., Turley, J., Kearney, C., Hill, R., Makhija, K., O'Brien, R., Keall, P., et al (2018). Impact of audiovisual biofeedback on interfraction respiratory motion reproducibility in liver cancer stereotactic body radiotherapy. Journal of Medical Imaging and Radiation Oncology, 62(1), 133-139. [More Information]
  • Lydiard, S., Caillet, V., Ipsen, S., O'Brien, R., Blanck, O., Poulsen, P., Booth, J., Keall, P. (2018). Investigating multi-leaf collimator tracking in stereotactic arrhythmic radioablation (STAR) treatments for atrial fibrillation. Physics in Medicine and Biology, 63(19), 1-13. [More Information]
  • Toftegaard, J., Keall, P., O'Brien, R., Ruan, D., Ernst, F., Homma, N., Ichiji, K., Poulsen, P. (2018). Potential improvements of lung and prostate MLC tracking investigated by treatment simulations. Medical Physics, 45(5), 2218-2229. [More Information]
  • Keall, P., Nguyen, D., O'Brien, R., Zhang, P., Happersett, L., Bertholet, J., Poulsen, P. (2018). Review of Real-Time 3-Dimensional Image Guided Radiation Therapy on Standard-Equipped Cancer Radiation Therapy Systems: Are We at the Tipping Point for the Era of Real-Time Radiation Therapy? International Journal of Radiation Oncology Biology Physics, 102(4), 922-931. [More Information]
  • Liu, P., Nguyen, D., Feain, L., O'Brien, R., Keall, P., Booth, J. (2018). Technical note: Real-time image-guided adaptive radiotherapy of a rigid target for a prototype fixed beam radiotherapy system. Medical Physics, 45(10), 4660-4666. [More Information]
  • Kim, J., Nguyen, D., Booth, J., Huang, C., Fuangrod, T., Poulsen, P., O'Brien, R., Caillet, V., Eade, T., Kneebone, A., Keall, P. (2018). The accuracy and precision of Kilovoltage Intrafraction Monitoring (KIM) six degree-of-freedom prostate motion measurements during patient treatments. Radiotherapy and Oncology, 126(2), 236-243. [More Information]
  • Keall, P., Nguyen, D., O'Brien, R., Caillet, V., Hewson, E., Poulsen, P., Bromley, R., Bell, L., Eade, T., Kneebone, A., Booth, J., et al (2018). The first clinical implementation of real-time image-guided adaptive radiotherapy using a standard linear accelerator. Radiotherapy and Oncology, 127(1), 6-11. [More Information]

2017

  • Lee, D., Greer, P., Lapuz, C., Ludbrook, J., Hunter, P., Arm, J., Pollock, S., Makhija, K., O'Brien, R., Kim, T., Keall, P. (2017). Audiovisual biofeedback guided breath-hold improves lung tumor position reproducibility and volume consistency. Advances in Radiation Oncology, 2(3), 354-362. [More Information]
  • Caillet, V., Keall, P., Colvill, E., Hardcastle, N., O'Brien, R., Szymura, K., Booth, J. (2017). MLC tracking for lung SABR reduces planning target volumes and dose to organs at risk. Radiotherapy and Oncology, 124(1), 18-24. [More Information]
  • Kim, J., Nguyen, D., Huang, C., Fuangrod, T., Caillet, V., O'Brien, R., Poulsen, P., Booth, J., Keall, P. (2017). Quantifying the accuracy and precision of a novel real-time 6 degree-of-freedom kilovoltage intrafraction monitoring (KIM) target tracking system. Physics in Medicine and Biology, 62(14), 5744-5759. [More Information]
  • O'Brien, R., Stankovic, U., Sonke, J., Keall, P. (2017). Reducing 4DCBCT imaging time and dose: The first implementation of variable gantry speed 4DCBCT on a linear accelerator. Physics in Medicine and Biology, 62(11), 4300-4317. [More Information]
  • Keall, P., Nguyen, D., O'Brien, R., Booth, J., Greer, P., Poulsen, P., Gebski, V., Kneebone, A., Martin, J. (2017). Stereotactic prostate adaptive radiotherapy utilising kilovoltage intrafraction monitoring: The TROG 15.01 SPARK trial. BMC Cancer, 17(1), 1-7. [More Information]
  • Feain, I., Coleman, L., Wallis, H., Sokolov, R., O'Brien, R., Keall, P. (2017). Technical Note: The design and function of a horizontal patient rotation system for the purposes of fixed-beam cancer radiotherapy. Medical Physics, 44(6), 2490-2502. [More Information]
  • Nguyen, D., O'Brien, R., Kim, J., Huang, C., Wilton, L., Greer, P., Legge, K., Booth, J., Poulsen, P., Martin, J., Keall, P. (2017). The first clinical implementation of a real-time six degree of freedom target tracking system during radiation therapy based on Kilovoltage Intrafraction Monitoring (KIM). Radiotherapy and Oncology, 123(1), 37-42. [More Information]

2016

  • Lee, D., Greer, P., Ludbrook, J., Arm, J., Hunter, P., Pollock, S., Makhija, K., O'Brien, R., Kim, T., Keall, P. (2016). Audiovisual Biofeedback Improves Cine-Magnetic Resonance Imaging Measured Lung Tumor Motion Consistency. International Journal of Radiation Oncology Biology Physics, 94(3), 628-636. [More Information]
  • Feain, I., Shieh, C., White, P., O'Brien, R., Fisher, S., Counter, W., Lazarakis, P., Stewart, D., Downes, S., Jackson, M., Whelan, B., Makhija, K., Huang, C., Keall, P., et al (2016). Functional imaging equivalence and proof of concept for image-guided adaptive radiotherapy with fixed gantry and rotating couch. Advances in Radiation Oncology, 1(4), 365-372. [More Information]
  • Keall, P., O'Brien, R., Cooper, B., Lu, J., Williamson, J. (2016). Optimising RMG-4DCBCT Image Acquisition. Patent No. 201280037958. China.
  • Ipsen, S., Bruder, R., O'Brien, R., Keall, P., Schweikard, A., Poulsen, P. (2016). Online 4D ultrasound guidance for real-time motion compensation by MLC tracking. Medical Physics, 43(10), 5695-5704. [More Information]
  • Keall, P., Ng, J., Juneja, P., O'Brien, R., Huang, C., Colvill, E., Caillet, V., Simpson, E., Poulsen, P., Kneebone, A., Eade, T., Booth, J. (2016). Real-Time 3D Image Guidance Using a Standard LINAC: Measured Motion, Accuracy, and Precision of the First Prospective Clinical Trial of Kilovoltage Intrafraction Monitoringe-Guided Gating for Prostate Cancer Radiation Therapy. International Journal of Radiation Oncology Biology Physics, 94(5), 1015-1021. [More Information]
  • Wisotzky, E., O'Brien, R., Keall, P. (2016). Technical Note: A novel leaf sequencing optimization algorithm which considers previous underdose and overdose events for MLC tracking radiotherapy. Medical Physics, 43(1), 132-136. [More Information]
  • O'Brien, R., Cooper, B., Shieh, C., Stankovic, U., Keall, P., Sonke, J. (2016). The first implementation of respiratory triggered 4DCBCT on a linear accelerator. Physics in Medicine and Biology, 61(9), 3488-3499. [More Information]
  • Booth, J., Caillet, V., Hardcastle, N., O'Brien, R., Szymura, K., Crasta, C., Harris, B., Haddad, C., Eade, T., Keall, P. (2016). The first patient treatment of electromagnetic-guided real time adaptive radiotherapy using MLC tracking for lung SABR. Radiotherapy and Oncology, 121(1), 19-25. [More Information]

2015

  • Pollock, S., O'Brien, R., Makhija, K., Hegi-Johnson, F., Ludbrook, J., Rezo, A., Tse, R., Eade, T., Yeghiaian-Alvandi, R., Gebski, V., Keall, P. (2015). Audiovisual biofeedback breathing guidance for lung cancer patients receiving radiotherapy: A multi-institutional phase II randomised clinical trial. BMC Cancer, 15(1), 1-8. [More Information]
  • Wallace, D., Ng, J., Keall, P., O'Brien, R., Poulsen, P., Juneja, P., Booth, J. (2015). Determining appropriate imaging parameters for kilovoltage intrafraction monitoring: an experimental phantom study. Physics in Medicine and Biology, 60(12), 4835-4847. [More Information]
  • Pollock, S., Tse, R., Martin, D., McLean, L., Cho, G., Hill, R., Pickard, S., Aston, P., Huang, C., Makhija, K., O'Brien, R., Keall, P. (2015). First clinical implementation of audiovisual biofeedback in liver cancer stereotactic body radiation therapy. Journal of Medical Imaging and Radiation Oncology, 59(5), 654-656. [More Information]
  • Shieh, C., Kipritidis, J., O'Brien, R., Cooper, B., Kuncic, Z., Keall, P. (2015). Improving thoracic four-dimensional cone-beam CT reconstruction with anatomical-adaptive image regularization (AAIR). Physics in Medicine and Biology, 60(2), 841-868. [More Information]
  • Colvill, E., Booth, J., O'Brien, R., Eade, T., Kneebone, A., Poulsen, P., Keall, P. (2015). Multileaf Collimator Tracking Improves Dose Delivery for Prostate Cancer Radiation Therapy: Results of the First Clinical Trial. International Journal of Radiation Oncology Biology Physics, 92(5), 1141-1147. [More Information]
  • Cooper, B., O'Brien, R., Kipritidis, J., Shieh, C., Keall, P. (2015). Quantifying the image quality and dose reduction of respiratory triggered 4D cone-beam computed tomography with patient-measured breathing. Physics in Medicine and Biology, 60(24), 9493-9513. [More Information]
  • Keall, P., Ng, J., O'Brien, R., Colvill, E., Huang, C., Poulsen, P., Flederlius, W., Juneja, P., Simpson, E., Bell, L., Booth, J., et al (2015). The first clinical treatment with kilovoltage intrafraction monitoring (KIM): A real-time image guidance method. Medical Physics, 42(1), 354-358. [More Information]

2014

  • Colvill, E., Poulsen, P., Booth, J., O'Brien, R., Ng, J., Keall, P. (2014). DMLC tracking and gating can improve dose coverage for prostate VMAT. Medical Physics, 41(9), 1-10. [More Information]
  • Shieh, C., Kipritidis, J., O'Brien, R., Kuncic, Z., Keall, P. (2014). Image quality in thoracic 4D cone-beam CT: a sensitivity analysis of respiratory signal, binning method, reconstruction algorithm, and projection angular spacing. Medical Physics, 41(4), 041912-1-041912-18. [More Information]
  • O'Brien, R., Kipritidis, J., Shieh, C., Keall, P. (2014). Optimizing 4DCBCT projection allocation to respiratory bins. Physics in Medicine and Biology, 59(19), 5631-5649. [More Information]
  • Ng, J., Booth, J., O'Brien, R., Colvill, E., Huang, C., Poulsen, P., Keall, P. (2014). Quality assurance for the clinical implementation of kilovoltage intrafraction monitoring for prostate cancer VMAT. Medical Physics, 41(11), 111712-1-111712-9. [More Information]
  • O'Brien, R., Cooper, B., Kipritidis, J., Shieh, C., Keall, P. (2014). Respiratory motion guided four dimensional cone beam computed tomography: Encompassing irregular breathing. Physics in Medicine and Biology, 59(3), 579-595. [More Information]
  • Keall, P., Colvill, E., O'Brien, R., Ng, J., Poulsen, P., Eade, T., Kneebone, A., Booth, J. (2014). The first clinical implementation of electromagnetic transponder-guided MLC tracking. Medical Physics, 41(2), 020702-1-020702-5. [More Information]
  • Ge, Y., O'Brien, R., Shieh, C., Booth, J., Keall, P. (2014). Toward the development of intrafraction tumor deformation tracking using a dynamic multi-leaf collimator. Medical Physics, 41(6), 061703-1-061703-10. [More Information]

2013

  • Pommer, T., Falk, M., Poulsen, P., Keall, P., O'Brien, R., Petersen, P., af Rosenschold, P. (2013). Dosimetric benefit of DMLC tracking for conventional and sub-volume boosted prostate intensity-modulated arc radiotherapy. Physics in Medicine and Biology, 58(7), 2349-2361. [More Information]
  • O'Brien, R., Cooper, B., Keall, P. (2013). Optimizing 4D cone beam computed tomography acquisition by varying the gantry velocity and projection time interval. Physics in Medicine and Biology, 58(6), 1705-1723. [More Information]
  • Nasehi Tehrani, J., O'Brien, R., Poulsen, P., Keall, P. (2013). Real-time estimation of prostate tumor rotation and translation with a kV imaging system based on an iterative closest point algorithm. Physics in Medicine and Biology, 58(23), 8517-8533. [More Information]
  • Cooper, B., O'Brien, R., Balik, S., Hugo, G., Keall, P. (2013). Respiratory triggered 4D cone-beam computed tomography: A novel method to reduce imaging dose. Medical Physics, 40(4), 041901-1-041901-9. [More Information]
  • Pommer, T., Falk, M., Poulsen, P., Keall, P., O'Brien, R., af Rosenschold, P. (2013). The impact of leaf width and plan complexity on DMLC tracking of prostate intensity modulated arc therapy. Medical Physics, 40(11), 111717-1-111717-6. [More Information]

2012

  • Kim, T., Pollock, S., Lee, D., O'Brien, R., Keall, P. (2012). Audiovisual biofeedback improves diaphragm motion reproducibility in MRI. Medical Physics, 39(11), 6921-6928. [More Information]

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