PhD Thesis Defense: Benjamin W. Maloney

For info on how to attend this videoconference, please email benjamin.w.maloney.TH@dartmouth.edu

"Combined Micro-CT and Optical Structured Light for Imaging during Breast Conserving Surgery"

Abstract

Breast Conserving Surgery (BCS), in combination with radiation therapy, is the most common treatment for early stage breast cancers in the United States. It involves surgical removal of the tumor with a thin margin of benign tissue, and is an effective treatment provided these margins are free of malignancy. However, 15-35% of patients require a second operation due to a positive margin found post-operatively in histologic analysis. This high rate of positive margins is due to a lack of suitable intraoperative tools. One promising method for surgical guidance is a multimodal system utilizing micro-computed tomography (micro-CT) for volumetric imaging of the interior structure of the specimen including tumor confirmation combined with optical structured light imaging (SLI) for surface scanning of the specimens to determine final margin status. Post-operative imaging studies have shown diagnostic potential of each modality under ideal conditions on tissues cut in a breadloaf style, and on a few select whole lumps. The same system is now deployed in surgery to assess its utility during direct clinical specimen imaging at the time of resection. Micro-CT scans were read by two radiologists under time constraints mimicking the clinic as part of this trial. Scans are able to be read in this time frame and micro-CT is capable of detecting additional positive margins. In addition, an improved system has been built with a focus on clinical use based on the optimal parameters found in the post-operative studies. This improved system features custom data collection and analysis tools optimized for this clinical problem. This thesis presents the clinical need for better intraoperative tools, pre-clinical research showing the potential of micro-CT and SLI to be better intraoperative tools, clinical results showing the clinical feasibility of micro-CT, and a specifically designed combined system for this purpose.

Thesis Committee

• Brian Pogue, PhD (Chair)
• Keith Paulsen, PhD
• Michael Jermyn, PhD
• Rebecca Zuurbier, MD
• Joshua Kempner, PhD (External)

Contact

For more information, contact Daryl Laware at daryl.a.laware@dartmouth.edu.