AbstractDdetection of micro-motion on biological tissues has various applications such as ultrasound elastography and magnetic resonance elastography (MRE). Ultrasound transducers, the most commonly used tool to detect endogenous and exogenous micro-motions, have a number of drawbacks: including the requirements of the physical contact with the sample and limited spatial resolution (millimetre scale). The aim of this thesis is to develop a non-contact phase-sensitive imaging technique which is suitable for functional imaging in the micron range which also has the potential for quantitative analysis of relative properties resulting from an appropriate image processing.
Concerning imaging techniques, this thesis focused on optical coherence tomography (OCT) and in particular on phase-sensitive optical coherence tomography (PhS-OCT). In this thesis, a PhS-OCT system is developed for micro-motion detection and a dual camera PhS-OCT system is developed to double the imaging acquiring speed and improve the sensitivity to small phase change. Two applications of PhS-OCT combining micro-motions detection are preformed: 1) Photo-thermal OCT (PT-OCT) system is developed to detect the photo-thermal phenomenon of nanoparticles. A mathematic model is proposed to analyse and reconstruct the distribution of nanoparticles in biological tissues. 2) A quantitative 3D optical coherence elastography (OCE) system and algorithm are developed to analysis the mechanical property of tissue. A feasibility study is carried for the diagnosis of prostate cancer (PCa) using this technique.
Results show that PhS-OCT is a powerful tool for the detection of micro-motions (micron range). Functional OCT based on it such as PT-OCT and OCE offers potential in diagnostic and therapeutic in clinical applications, e.g. PT-OCT can be used to detect and map the distribution and concentration of dye and drug in tissues or organs. 3D OCE can provide useful information for early localization and diagnosis of cancer.
|Date of Award||2015|
|Supervisor||Zhihong Huang (Supervisor)|