Optimized Fidelity and Mobilization of an In-Vivo Photoacoustic Skin Imaging System

Abstract

Biomedical imaging of skin cancers for evaluation and non-invasivetracking of progress to therapies has a gap in mainstream industry for lesions that present in deep dermal areas of the body. Optical imaging methods available have varying limitations when assessing between healthy skin tissue and different types of skin cancers deep within the tissue. Photoacoustic tomography (PAT) has gained popularity for its ability to provide specific tissue structure and composition at depths of 1 cm or greater. Data that can be resolved at sub 1 cm depths or can open a path in clinical imaging of lesions that is highly desirable. This master’s thesis lays out a variation of a cost-effective, second generation version of a portable clinical hybrid pulse echo (PE) and Photoacoustic tomography 3D imaging system that was originally developed for in-vivo assessment and monitoring of common cutaneous skin lesions in dermatology clinical settings. This second version addressed a few of the challenges and limitations of the original design in preparation for use at a clinic. This version offers many of the original systems features such as 3D volume PE and PAT scans capable of performing spectroscopy within the near infrared range (680 nm - 1000 nm) with the added value for potential to change transducers as the need arises for clinical imaging. The design changes to the system allow for maintenance time reduction of 48 hours turnaround time to 15 minutes. This thesis also introduces a portable cart-based system for patient imaging in a clinic. It enables imaging in a patient in a safe manner while allowing for a technician to both operate, monitor the exam, and characterize suspicious skin lesions in real time. The system also has potential use for a simple transducer substitution, as needed, depending on the clinician’s preference based on the characteristics of the transducer. This ability would open doors for tuned patient assessment and treatment monitoring.