Rajiv Chopra

Summary

Affiliation: University of Toronto
Country: Canada

Publications

  1. ncbi request reprint MR imaging-controlled transurethral ultrasound therapy for conformal treatment of prostate tissue: initial feasibility in humans
    Rajiv Chopra
    Imaging Research, Sunnybrook Research Institute, 2075 Bayview Ave, Room C713, Toronto, ON, Canada M4N 3M5
    Radiology 265:303-13. 2012
  2. doi request reprint In vivo MR elastography of the prostate gland using a transurethral actuator
    Rajiv Chopra
    Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Magn Reson Med 62:665-71. 2009
  3. pmc An MRI-compatible system for focused ultrasound experiments in small animal models
    Rajiv Chopra
    Imaging Research, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada
    Med Phys 36:1867-74. 2009
  4. doi request reprint Analysis of the spatial and temporal accuracy of heating in the prostate gland using transurethral ultrasound therapy and active MR temperature feedback
    Rajiv Chopra
    Imaging Research, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, ON, M4N 3M5, Canada
    Phys Med Biol 54:2615-33. 2009
  5. ncbi request reprint MRI-compatible transurethral ultrasound system for the treatment of localized prostate cancer using rotational control
    Rajiv Chopra
    Sunnybrook Health Sciences Centre, Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
    Med Phys 35:1346-57. 2008
  6. doi request reprint MRI-controlled transurethral ultrasound therapy for localised prostate cancer
    Rajiv Chopra
    Imaging Research, Centre for Research in Image Guided Therapeutics, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Int J Hyperthermia 26:804-21. 2010
  7. ncbi request reprint Method for MRI-guided conformal thermal therapy of prostate with planar transurethral ultrasound heating applicators
    Rajiv Chopra
    Sunnybrook and Women s College Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
    Phys Med Biol 50:4957-75. 2005
  8. doi request reprint MRI-guided transurethral ultrasound therapy of the prostate gland using real-time thermal mapping: initial studies
    Kashif Siddiqui
    Department of Urology, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Urology 76:1506-11. 2010
  9. doi request reprint Investigation of power and frequency for 3D conformal MRI-controlled transurethral ultrasound therapy with a dual frequency multi-element transducer
    William Apoutou N'Djin
    Imaging Research, Sunnybrook Health Sciences Centre, and Department of Medical Biophysics, University of Toronto, Ontario, Canada
    Int J Hyperthermia 28:87-104. 2012
  10. ncbi request reprint Analysis of factors important for transurethral ultrasound prostate heating using MR temperature feedback
    Rajiv Chopra
    Sunnybrook and Women s College Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada
    Phys Med Biol 51:827-44. 2006

Collaborators

Detail Information

Publications40

  1. ncbi request reprint MR imaging-controlled transurethral ultrasound therapy for conformal treatment of prostate tissue: initial feasibility in humans
    Rajiv Chopra
    Imaging Research, Sunnybrook Research Institute, 2075 Bayview Ave, Room C713, Toronto, ON, Canada M4N 3M5
    Radiology 265:303-13. 2012
    ..To evaluate the feasibility and safety of magnetic resonance (MR) imaging-controlled transurethral ultrasound therapy for prostate cancer in humans...
  2. doi request reprint In vivo MR elastography of the prostate gland using a transurethral actuator
    Rajiv Chopra
    Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Magn Reson Med 62:665-71. 2009
    ..These experiments demonstrate the technical feasibility of transurethral MRE in vivo. Further development of this technique is warranted...
  3. pmc An MRI-compatible system for focused ultrasound experiments in small animal models
    Rajiv Chopra
    Imaging Research, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada
    Med Phys 36:1867-74. 2009
    ..Initial results suggest that this is a robust and precise apparatus for use in the investigation of novel ultrasound-based therapeutic strategies in small animal preclinical models...
  4. doi request reprint Analysis of the spatial and temporal accuracy of heating in the prostate gland using transurethral ultrasound therapy and active MR temperature feedback
    Rajiv Chopra
    Imaging Research, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, ON, M4N 3M5, Canada
    Phys Med Biol 54:2615-33. 2009
    ..This study demonstrates the benefit of adaptive energy delivery using active MR temperature feedback, and an excellent capability to treat precise regions within the prostate gland with this technology...
  5. ncbi request reprint MRI-compatible transurethral ultrasound system for the treatment of localized prostate cancer using rotational control
    Rajiv Chopra
    Sunnybrook Health Sciences Centre, Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
    Med Phys 35:1346-57. 2008
    ..The technical feasibility of using the system developed in this study for MRI-guided transurethral ultrasound therapy in a closed-bore MR imager has been demonstrated...
  6. doi request reprint MRI-controlled transurethral ultrasound therapy for localised prostate cancer
    Rajiv Chopra
    Imaging Research, Centre for Research in Image Guided Therapeutics, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Int J Hyperthermia 26:804-21. 2010
    ..Recent human experience has been encouraging and motivates further evaluation of this technology as a potential treatment for localised prostate cancer...
  7. ncbi request reprint Method for MRI-guided conformal thermal therapy of prostate with planar transurethral ultrasound heating applicators
    Rajiv Chopra
    Sunnybrook and Women s College Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
    Phys Med Biol 50:4957-75. 2005
    ..Experimental validation of the simulations in a tissue-mimicking gel phantom demonstrated good agreement between the predicted and generated patterns of thermal damage...
  8. doi request reprint MRI-guided transurethral ultrasound therapy of the prostate gland using real-time thermal mapping: initial studies
    Kashif Siddiqui
    Department of Urology, University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Urology 76:1506-11. 2010
    ..To confirm the correlation between planning and thermal injury of the prostate as determined by magnetic resonance imaging (MRI) and histology in canine and humans treated with transurethral ultrasound...
  9. doi request reprint Investigation of power and frequency for 3D conformal MRI-controlled transurethral ultrasound therapy with a dual frequency multi-element transducer
    William Apoutou N'Djin
    Imaging Research, Sunnybrook Health Sciences Centre, and Department of Medical Biophysics, University of Toronto, Ontario, Canada
    Int J Hyperthermia 28:87-104. 2012
    ..The interdependence between power and frequency may, however, require integrating multi-parametric functions in the controller for future optimisations...
  10. ncbi request reprint Analysis of factors important for transurethral ultrasound prostate heating using MR temperature feedback
    Rajiv Chopra
    Sunnybrook and Women s College Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada
    Phys Med Biol 51:827-44. 2006
    ..5 T imaging systems is of sufficient quality for use as thermal feedback for conformal prostate thermal therapy with transurethral ultrasound heating applicators incorporating planar transducers...
  11. doi request reprint Quantitative analysis of 3-D conformal MRI-guided transurethral ultrasound therapy of the prostate: theoretical simulations
    Mathieu Burtnyk
    Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto, Ontario, Canada
    Int J Hyperthermia 25:116-31. 2009
    ..The capability of MRI-guided transurethral ultrasound therapy to produce continuous regions of thermal coagulation that conform to human prostate geometries was evaluated using 3-D anatomical models of prostate cancer patients...
  12. pmc Evaluation of Focal Ablation of Magnetic Resonance Imaging Defined Prostate Cancer Using Magnetic Resonance Imaging Controlled Transurethral Ultrasound Therapy with Prostatectomy as the Reference Standard
    Elizabeth Ramsay
    Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
    J Urol . 2016
    ..We evaluated magnetic resonance imaging controlled transurethral ultrasound therapy as a treatment for magnetic resonance imaging defined focal prostate cancer using subsequent prostatectomy and histology as the reference standard...
  13. doi request reprint Hyperthermia in bone generated with MR imaging-controlled focused ultrasound: control strategies and drug delivery
    Robert Staruch
    Centre for Research in Image Guided Therapeutics, Sunnybrook Health Sciences Centre, Toronto, ON, Canada M4N 3M5
    Radiology 263:117-27. 2012
    ..To evaluate the feasibility of achieving image-guided drug delivery in bone by using magnetic resonance (MR) imaging-controlled focused ultrasound hyperthermia and temperature-sensitive liposomes...
  14. ncbi request reprint Prostate tissue analysis immediately following magnetic resonance imaging guided transurethral ultrasound thermal therapy
    Aaron Boyes
    Research and Anatomic Pathology, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    J Urol 178:1080-5. 2007
    ..In particular the boundary of tissue coagulation was analyzed to quantify the treatment margin resulting from this technology...
  15. pmc MR thermometry in the human prostate gland at 3.0T for transurethral ultrasound therapy
    Elizabeth Ramsay
    Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
    J Magn Reson Imaging 38:1564-71. 2013
    ....
  16. pmc In vivo monitoring of focused ultrasound surgery using local harmonic motion
    Laura Curiel
    Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Ultrasound Med Biol 35:65-78. 2009
    ..LHM measurements were also used to perform a spatial scan of the tissues across the exposure region and the thermal lesions could be detected as a reduction in the maximum motion amplitude value at the sonication region...
  17. ncbi request reprint Simulation study on the heating of the surrounding anatomy during transurethral ultrasound prostate therapy: a 3D theoretical analysis of patient safety
    Mathieu Burtnyk
    Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada
    Med Phys 37:2862-75. 2010
    ..This work simulated, quantified, and evaluated the thermal impact of these treatments on the rectum, pelvic bone, neurovascular bundles (NVBs), and urinary sphincters because damage to these structures can lead to complications...
  18. doi request reprint Incorporating endorectal MR elastography into multi-parametric MRI for prostate cancer imaging: Initial feasibility in volunteers
    Arvin Arani
    Physical Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
    J Magn Reson Imaging 38:1251-60. 2013
    ..To investigate the tolerability and technical feasibility of performing endorectal MR elastography (eMRE) in human volunteers within the representative age group commonly affected by prostate cancer...
  19. doi request reprint Arterial input function calculation in dynamic contrast-enhanced MRI: an in vivo validation study using co-registered contrast-enhanced ultrasound imaging
    Hatef Mehrabian
    Department of Medical Biophysics, Sunnybrook Research Institute, University of Toronto, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
    Eur Radiol 22:1735-47. 2012
    ....
  20. doi request reprint The feasibility of endorectal MR elastography for prostate cancer localization
    Arvin Arani
    Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Magn Reson Med 66:1649-57. 2011
    ..1 cc (0.6 cm diameter) spherical inclusion volumes. Therefore, the results of this study, in combination with current clinical practice, motivate clinical evaluation of endorectal MRE in patients...
  21. doi request reprint Calculation of intravascular signal in dynamic contrast enhanced-MRI using adaptive complex independent component analysis
    Hatef Mehrabian
    Department of Medical Biophysics, University of Toronto, Toronto, ON, M5G 2M9 Canada
    IEEE Trans Med Imaging 32:699-710. 2013
    ..Thus, AC-ICA has the potential to be used as the intravascular time-intensity curve calculation method in PK analysis and could lead to more accurate PK analysis for tumors...
  22. doi request reprint Enhanced drug delivery in rabbit VX2 tumours using thermosensitive liposomes and MRI-controlled focused ultrasound hyperthermia
    Robert M Staruch
    Centre for Research in Image Guided Therapeutics, Sunnybrook Research Institute, Toronto, Ontario, Canada
    Int J Hyperthermia 28:776-87. 2012
    ....
  23. doi request reprint 3D conformal MRI-controlled transurethral ultrasound prostate therapy: validation of numerical simulations and demonstration in tissue-mimicking gel phantoms
    Mathieu Burtnyk
    Sunnybrook Health Sciences Centre, 2075 Bayview Ave, Toronto, ON, M4N3M5, Canada
    Phys Med Biol 55:6817-39. 2010
    ..The accuracy of numerical simulations for MRI-controlled transurethral ultrasound prostate therapy was validated experimentally, reinforcing their utility as an effective treatment planning tool...
  24. pmc Coagulation of human prostate volumes with MRI-controlled transurethral ultrasound therapy: results in gel phantoms
    William Apoutou N'Djin
    Imaging Research, Sunnybrook Research Institute, Toronto, Ontario M4N3M5, Canada
    Med Phys 39:4524-36. 2012
    ..The aim of this study was to investigate the parameters required to treat a full 3D human prostate accurately with a multi-element transurethral applicator and multiplanar MR temperature control...
  25. ncbi request reprint Multifrequency ultrasound transducers for conformal interstitial thermal therapy
    Rajiv Chopra
    Sunnybrook and Women s College Health Sciences Centre, Department of Medical Biophysics, University of Toronto, Toronto, ON M4N 3M5, Canada
    IEEE Trans Ultrason Ferroelectr Freq Control 50:881-9. 2003
    ..Practical interstitial designs that enable the generation of shaped thermal lesions are feasible...
  26. pmc MR acoustic radiation force imaging: in vivo comparison to ultrasound motion tracking
    Yuexi Huang
    Sunnybrook Health Sciences Centre, Toronto, Ontario M4N 3M5, Canada
    Med Phys 36:2016-20. 2009
    ..96 and R2=0.67). The temporal information by the ultrasound measurement indicates that the parameters in MR ARF imaging should be optimized according to the tissue type, acoustic power, and envelope and frequency of the ARF modulation...
  27. pmc Progress in multimodality imaging: truly simultaneous ultrasound and magnetic resonance imaging
    Laura Curiel
    Imaging Research Department at Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M5, Canada
    IEEE Trans Med Imaging 26:1740-6. 2007
    ..This demonstration of technical feasibility and the development of a prototype system open up the potential to investigate the promising clinical applications of this combined technology...
  28. doi request reprint Localised drug release using MRI-controlled focused ultrasound hyperthermia
    Robert Staruch
    Centre for Research in Image Guided Therapeutics, Sunnybrook Health Sciences Centre, Toronto, Canada
    Int J Hyperthermia 27:156-71. 2011
    ..The objective of this study was to evaluate the feasibility of using MRI-controlled focused ultrasound (FUS) and thermosensitive liposomes to achieve thermally mediated localised drug delivery in vivo...
  29. doi request reprint Transurethral prostate magnetic resonance elastography: prospective imaging requirements
    Arvin Arani
    Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
    Magn Reson Med 65:340-9. 2011
    ..These requirements are achievable with current imaging and actuator technologies, and motivate further investigation of magnetic resonance elastography for the targeting of prostate cancer...
  30. doi request reprint Development of a new control strategy for 3D MRI-controlled interstitial ultrasound cancer therapy
    Amin Yazdanpanah Goharrizi
    Department of Electrical and Computer Engineering, University of Toronto, Toronto, Canada
    Med Phys 40:033301. 2013
    ..The method uses an interstitial multielement ultrasound applicator to deliver high-intensity ultrasound energy to tissue in order to achieve thermal coagulation in a target volume...
  31. doi request reprint Real-time correction by optical tracking with integrated geometric distortion correction for reducing motion artifacts in functional MRI
    David Rotenberg
    Rotman Research Institute, Baycrest, Toronto, Canada
    Magn Reson Med 69:734-48. 2013
    ..Experiments suggest that such integrated volume-by-volume corrections are very effective at artifact suppression, with potential to expand functional MRI applications...
  32. ncbi request reprint Multi-modality tissue-mimicking phantom for thermal therapy
    Mark McDonald
    Sunnybrook and Women s College Health Sciences Centre and Department of Medical Biophysics, University of Toronto, 2075 Bayview Ave, Toronto, Ontario, M4N 3M5, Canada
    Phys Med Biol 49:2767-78. 2004
    ..T2 relaxation measurements are provided as a function of temperature, along with T2-weighted MR images to illustrate the visualization of heating patterns. A complete recipe for fabricating phantoms is provided...
  33. doi request reprint Thermally-triggered 'off-on-off' response of gadolinium-hydrogel-lipid hybrid nanoparticles defines a customizable temperature window for non-invasive magnetic resonance imaging thermometry
    Adam J Shuhendler
    Department of Pharmaceutical Sciences, Leslie L Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada M5S 3M2
    J Control Release 157:478-84. 2012
    ..This allowed MRI thermometry of different temperature windows using the Gd-HLN system...
  34. doi request reprint Development of a platform for co-registered ultrasound and MR contrast imaging in vivo
    Chaitanya Chandrana
    Sunnybrook Health Sciences Centre, Imaging Research, Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
    Phys Med Biol 56:861-77. 2011
    ..This study demonstrates the feasibility of performing in vivo co-registered contrast US and MR imaging to study the relationships of the enhancement patterns with each modality...
  35. pmc Temperature-dependent MR signals in cortical bone: potential for monitoring temperature changes during high-intensity focused ultrasound treatment in bone
    Elizabeth Ramsay
    Sunnybrook Research Institute, Toronto, Canada
    Magn Reson Med 74:1095-102. 2015
    ..In this study, the potential to monitor temperature changes in cortical bone using a short TE gradient echo sequence is evaluated...
  36. pmc Development of robust/predictive control strategies for image-guided ablative treatments using a minimally invasive ultrasound applicator
    Amin Yazdanpanah Goharrizi
    Department of Electrical and Computer Engineering, University of Toronto, Toronto, Canada
    Int J Hyperthermia 30:438-46. 2014
    ..Furthermore, tissue properties such as perfusion and energy absorption can be dynamic and difficult to measure. This paper attempts to address these problems by proposing new control methods...
  37. doi request reprint Hyperthermia-mediated doxorubicin release from thermosensitive liposomes using MR-HIFU: therapeutic effect in rabbit Vx2 tumours
    Robert M Staruch
    Physical Sciences Platform, Sunnybrook Research Institute, Toronto, Ontario, Canada
    Int J Hyperthermia 31:118-33. 2015
    ....
  38. pmc Antibodies targeted to the brain with image-guided focused ultrasound reduces amyloid-beta plaque load in the TgCRND8 mouse model of Alzheimer's disease
    Jessica F Jordão
    Brain Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada
    PLoS ONE 5:e10549. 2010
    ..In conclusion, this is the first report to demonstrate that MRIgFUS delivery of anti-Abeta antibodies provides the combined advantages of using a low dose of antibody and rapidly reducing plaque pathology...
  39. pmc MRI-guided disruption of the blood-brain barrier using transcranial focused ultrasound in a rat model
    Meaghan A O'Reilly
    Imaging Research, Sunnybrook Research Institute
    J Vis Exp . 2012
    ..This protocol outlines how to achieve MRI-guided FUS induced BBBD in a rat model, with a focus on the critical animal preparation and microbubble handling steps of the experiment...
  40. pmc Spatiotemporal filtering of MR-temperature artifacts arising from bowel motion during transurethral MR-HIFU
    Alain Schmitt
    Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5, Canada
    Med Phys 41:113302. 2014
    ....