Steven Babic

Research Synopsis

My current projects include 1) accurate volumetric measurements of radiation doses using radiochromic gel dosimeters and optical CT scanners, 2) evaluating a non-invasive immobilization technique for stereotactic radiosurgery (SRS) and 3) implementing a photodynamic therapy (PDT) clinical program for treating superficial skin cancer. 1) To assure the quality of advanced 3D radiation cancer treatment planning software and dose delivery hardware, it is important that the spatial distribution of ionizing radiation deposited within the exposed tissues be accurately and precisely mapped out. I am interested in investigating the optimal optical CT scanner light source and geometry for quantitatively reading the dose in 3D that is “written” into a radiochromic gel during a setup that emulates patient treatment conditions. 2) The reliable immobilization and target localization accuracy of frame-based SRS have established the technique as a gold standard, but it is associated with significant disadvantages including stress on the patient, and the need to simulate, plan and treat patients all in the same day. My interest lies in evaluating commercially available non-invasive immobilization systems that overcome frame-based limitations. By doing an inter-comparison of their respective positional accuracies, my research goal is to determine which system offers the highest degree of immobilization and ease of use for SRS patients. 3) One type of PDT is used to destroy non-melanoma superficial skin cancers. Some patients receiving this therapy are ones who have already received conventional treatments and have not had much success. Photosensitive compounds in the form of a topical cream are applied and selectively up taken by the cancerous cells. Subsequent illumination with red light results in lethal cell damage. My research interest lies in better understanding what physical measurements are needed to predict the response of individual patients to PDT and to optimize their treatment. Ultimately the goal will be to increase the clinical utilization of this mode of skin cancer therapy.

Recent Publications

Mark Ruschin, Young Lee, David Beachey, Collins Yeboah, Matt Wronski, Steven Babic, Collins Yeboah, Fiona Lochray, Anula Nico, Luluel Khan, Young Lee, Hany Soliman and Arjun Sahgal. Investigation of dose falloff for intact brain metastases and surgical cavities using hypofractionated volumetric modulated arc radiotherapy. Technology in Cancer Research & Treatment. January 26 (2015). Current Impact Factor: 1.886

Mark Ruschin, Alexander Lightstone, David Beachey, Matt Wronski, Steven Babic, Collins Yeboah, Young Lee, Hany Soliman and Arjun Sahgal. Quality assurance results for a commercial radiosurgery system: A communication. Technology in Cancer Research & Treatment. June 16 (2014). Current Impact Factor: 1.886

Steven Babic and Kevin Jordan. The performance of an optical cone-beam CT scanner adapted for radiochromic film dosimetry. Phys. Med. Biol. 57: N377-N389 (2012). Current Impact Factor: 2.922

Steven Babic, Jerry Battista and Kevin Jordan. Radiochromic leuco dye micelle hydrogels: II. Low diffusion rate leuco crystal violet gel. Phys. Med. Biol. 54: 6791-808 (2009). Current Impact Factor: 2.922

Steven Babic, Jerry Battista and Kevin Jordan. Three-dimensional dosimetry of small megavoltage radiation fields using radiochromic gels and optical CT scanning. Phys. Med. Biol. 54: 2463-81 (2009). Current Impact Factor: 2. 2.922

Steven Babic, Jerry Battista and Kevin Jordan. An apparent threshold dose response in ferrous xylenol-orange gel dosimeters when scanned with a yellow light source. Phys. Med. Biol. 53: 1637 – 50 (2008). Current Impact Factor: 2.922

Steven Babic, Jerry Battista and Kevin Jordan. Three-dimensional dose verification for intensity-modulated radiation therapy in the Radiological Physics Centre head-and-neck phantom using optical computed tomography scans of ferrous xylenol-orange gel dosimeters. Int. J. Radiation Oncology Biol. Phys. 70: 1281 – 91 (2008). Current Impact Factor: 4.176

Steven Babic and L John Schreiner. An NMR relaxometry and gravimetric study of gelatin-free aqueous polyacrylamide dosimeters. Phys. Med. Biol. 51: 4171 – 87 (2006). Current Impact Factor: 2.922

Steven Babic, Andrew Kerr, Mary Westerland, Jim Gooding and L John Schreiner. Examination of Jeltrate Plus as a tissue equivalent bolus material. J. Appl. Clin. Med. Phys. 3: 170-5 (2002). Current Impact Factor: 1.29

Appointments

• Deputy Head and Medical Physicist, Department of Medical Physics, Odette Cancer Centre – Sunnybrook Health Sciences Centre,
• Assistant Professor, Department of Radiation Oncology, University of Toronto