Bruce R. Thomadsen

Research Interests

• Investigation of methods of quantization of radiation dose in tissue
• Evaluation of dose distributions in tissue, particularly in brachytherapy, and in conformal treatment utilizing multimodality imaging
• Measurement of radiation from various sources
• Development and application of safety practices in radiation therapy

Thomadsen Laboratory – Current Research Projects

• An evaluation of the effective dose for patients receiving radiotherapy – a follow-up to NCRP Report 160. This project considers the population exposure for patients receiving radiotherapy in the United States. Student: Adam Uselmann.(Submitted to Health Physics.)
• An evaluation of the effect of air pockets or voids trapped on the surface of a breast-brachytherapy balloon on tumor control probability. Commonly, such pockets originally of air and later filled with fluid displace tissues to be treated with a radioactive source in a balloon filling a lumpectomy cavity. There is concern that the tissues pushed away from the balloon will not receive the treatment doses.Students: Andrew Ellis and Jay Yang. (Manuscript in preparation).
• An assessment of the stability of directional brachytherapy sources in vivo. Our lab developed directional sources for implants. However, their use raises the question as to whether the sources will continue to point in the correct direction over the duration of the treatment. This project investigates the stability of such sources. Student: Kyle Jamar.
• Development of an assay methodology for permanent-implant sources in sterile packaging. Prostate implants frequently are performed using sources loaded into needles, sterilized and and sealed in packages by the manufacturer or pharmacies. Assaying the sources without violating the sterility and integrity of the packaging is a problem. We are developing an quick and simple assay technique to address this need. Students: Matthew Berggruen and Kevin Beene.
• Development of an image-guided, directional high dose-rate brachytherapy unit. Image-guidance in brachytherapy has outpaced the ability to sculpt the dose distribution to the target. This project is developing a device to allow high dose-rate treatments that conform to identified targets. In collaboration with Douglass Henderson. Student: Athena Heredia.
• A study investigating the feasibility of on-board, PET-guided TomoTherapy. Conventional TomoTherapy used megavoltage CT to guide the treatments based on the patient’s anatomy at the time to therapy. Positron emission tomography (PET) imaging maps the physiology of tumors and could be used to target cancers based on their metabolism. In this project, we are looking at the feasibility of marrying a PET scanner to a TomoTherapy unit. Student: Naser Darwish.
• Development of a robotic brachytherapy delivery device. Implantation of sources for brachytherapy could be performed more accurately and efficiently under robotic control. This project is developing a brachytherapy robot.
• Expansion of an adjoint-greedy heuristic optimization methodology in brachytherapy and intensity-modulated radiotherapy. This approach for determining where to place brachytherapy sources, a process called optimization, has proven to be the fastest technique. This project is developing its capabilities and applications. In collaboration with Douglass Henderson.
• Formalizing a rational methodology for establishing quality management programs. The application of techniques that originated in industrial engineering have shown to be useful in developing a rationale quality management program for medical settings. However, medical applications present some very special needs that require some different tools. This project is developing those tools.