Professor Emeritus, Division of Medical Physics, Department of Oncology, University of Alberta

Senior Medical Physicist, Dept. of Medical Physics, CCI
Retired 2019.

BSc Hons Physics: Manitoba-1974
PhD Nuclear Physics: Alberta -1979

Fellow:Canadian College of Physicists in Medicine

Research Interests

My main research interests are dosimetry and treatment planning for brachytherapy, including the design of clinical studies to obtain patient data that inform model-based dose calculation. Our group has made use of Monte Carlo methods, thermoluminscent dosimeters, and radiochromic film to calculate and measure reference dose distributions around a variety of brachytherapy sources in the recent past. Current work is focused on incorporating MRI in the treatment planning, delivery, and evaluation processes, particularly for permanent prostate implants and intracavitary/interstitial cervix treatments. Serial imaging studies conducted in collaboration with the Radiation Oncology and Cancer Imaging departments are designed to elucidate the spatio-temporal behaviour of radiation sources and surrounding tissue over the course of brachytherapy treatment. Such data form the basis for improvements in clinical dosimetry that in turn have the potential to improve clinical outcomes.

Selected Publications

Lehmann T, Sloboda R, Usmani N, Tavakoli M. Model-based needle steering in soft tissue via lateral needle actuation. IEEE Robotics and Automation Letters 2018; 3:3930-3936

Morrison H, Menon G, Larocque MP, van Veelen B, Niatsetski Y, Weis E, Sloboda R. Advanced Collapsed-cone Engine dose calculations in tissue media for COMS eye plaques loaded with I-125 seeds. Med Phys 2018; 45:3349-3360

Morrison H, Menon G, Larocque MP, van Veelen B, Niatsetski Y, Weis E, Sloboda R. Initial evaluation of Advanced Collapsed-cone Engine dose calculations in water medium for I-125 seeds and COMS eye plaques. Med Phys 2018; 45:1276-1286

Babadagli ME, Doucette J, Usmani N, Amanie J, Murtha A, Yee D, Jamaluddin M, Sloboda R. Initial clinical assessment of "center-specific" automated treatment plans for low dose rate prostate brachytherapy. Brachytherapy 2018; 17:476-488

Cawston-Grant B, Morrison H, Sloboda R, Menon G. Experimental assessment of the Advanced Collapsed-cone Engine for scalp brachytherapy treatments. Brachytherapy 2018; 17:489-499.

Ma Y, Vijande J, Ballester F, Tedgren ÅC, Granero D, Haworth A, Mourtada F, Fonseca GP, Zourari K, Papagiannis P, Rivard MJ, Siebert FA, Sloboda R, Smith R, Chamberland MJP, Thomson RM, Verhaegen F, Beaulieu L. A generic TG-186 shielded applicator for commissioning model-based dose calculation algorithms for high-dose-rate ¹⁹²Ir brachytherapy. Med Phys 2017; 44:5961-5976

Cawston-Grant B, Morrison H, Menon G, Sloboda R. Experimental verification of Advanced Collapsed-cone Engine for use with a multichannel vaginal cylinder applicator. J Appl Clin Med Phys 2017; 18:16-27

Sloboda R, Morrison H, Cawston-Grant B, Menon GV. A brief look at model-based dose calculation principles, practicalities, and promise. [invited review article] J Contemp Brachytherapy 2017; 9:79-88

Morrison H, Menon GV, Larocque M, Hans-Sonke J, Weis E, Sloboda R. Delivered dose uncertainty analysis at the tumor apex for ocular brachytherapy. Med Phys 2016; 43:4891-4902

Rossa C, Usmani N, Sloboda R, Tavakoli M. A hand-held assistant for semiautomated percutaneous needle steering. IEEE Trans Biomed Eng 2016; 64:637-648

Weis E, Salopek TG, McKinnon JG, Larocque MP, Temple-Oberle C, Cheng T, McWhae J, Sloboda RS, Shea-Budgell M. Management of uveal melanoma: a consensus-based provincial clinical practice guideline. Current Oncology 2016; 23:e57-e64

Liu D, Meyer T, Usmani N, Kay I, Husain S, Angyalfi S, Sloboda R. Implanted brachytherapy seed movement reflecting transrectal ultrasound probe-induced prostate deformation. Brachytherapy 2015; 14:809-817

Ballester F, Carlsson-Tedgren Å, Granero D, Haworth A, Mourtada F, Fonseca GP, Zourari K, Panagiotis P, Rivard M, Siebert, F-A, Sloboda R, Smith R, Thomson RM, Verhaegen F, Vijande J, Ma Y, Beaulieu L. A generic high-dose-rate ¹⁹²Ir brachytherapy source for evaluation of model-based dose calculations beyond the TG-43 formalism. Med Phys 2015; 42:3048-3062