Clinical MR-Guided Brachytherapy Treatment Outcomes

Brachytherapy is a form of prostate cancer treatment where radioactive seeds are placed inside the malignant prostate tissue with a goal of destroying it. More conventional forms of treatment can cause a myriad of clinical problems after treatment. MR-guided brachytherapy attempts to limit radiation dosage, and thereby poor post-brachytherapy outcomes, through more accurate targeting using MRI guidance.

Image Registration

Registration is a technique that allows medical images, from modalities such as MRI, taken at different times and from different positions to still be visualized as the same person/prostate. For example, when an organ changes shape and treatment targeting must match biopsy data, image registration can be very useful. We are developing a non-rigid registration scheme that can account for glandular position changes as well as differences over time.

Signal Inhomogeneity Correction

The signal inhomogeneity correction project is concerned with creating more accurate and consistent MRI images. For MRI an endorectal coil is effectively used to boost signal, but the farther away from the coil, the less sharp the image tends to be. Instead of brighter patches corresponding solely to the type of tissue, it also corresponds to the distance from the coil. To correct this, an algorithm can be introduced to reduce this proximity bias.

Image Segmentation

Image segmentation can be accomplished by manually outlining targeted tissues such as the prostate or by automated anotomical segmentation. Segmentation is useful for many reasons including ascertaining information such as the volume of the prostate or allowing for color-coded 3D rendering of targeted tissues. This can help clinicians more accurately evaluate where the position of tumors in relation to vital organs and tissues and more effecient treatment.

MR-Compatible Robotics

Roboticsis an emerging field in MR-therapy and will become increasingly important as the field evolves. Intraprocedural robotics may allow for more accurate and effective clinical treatment. For example, robotic needle guidance makes it possible to achieve very precise and flexible alignment with needle trajectories, which is more accurate than human hands can be.

Statistical Validation and Support, Kelly Zou, Ph.D.

MR-Spectroscopy, Robert Mulkern, Ph.D.