Quantitative stress-induced birefringence measurement on chicken tendon using PS-OCT.

• Main Author: Lin, Anle.
• Other Authors: Lee Kijoon
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/53692
• Institution: Nanyang Technological University

Optical coherence tomography (OCT), an optical analogue of ultrasound imaging, is a useful tool for structural imaging with a resolution of . Spectral analysis of OCT signals can provide additional information on the scattering properties in the sample. Polarisation-sensitive OCT (PS-OCT) is an extension of OCT which utilizes the extra information of polarization state to generate enhanced contrast in images as compared to other OCT modalities. PS-OCT can therefore provide specificity in structures identification in the OCT images, which can be useful since changes in birefringence may suggest changes in tissue function or viability. Birefringence also allows quantitative measurement which will be discussed in the report. In this work, stress induced on chicken tendon was investigated. PS-OCT was used to obtain birefringence on chicken tendon where incremental force is applied in the axial direction. Raw data is obtained and image processing techniques were explored to obtain information for analysis. The results demonstrate that as stress increases, birefringence increases. With the linear relationship, by evaluating the birefringence pattern, stress-birefringence equation was obtained which correlates stress to birefringence. Experiments were performed to evaluate the stress- birefringence equations and determined that the equation can be used to estimate the stress induced on the chicken tendon by measuring the birefringence. Challenges and problems were faced during the course of experiments. In order to get optimum PS-OCT system, the alignment of the light source must be précised. It requires patience and determination to produce quality images. Artefacts were found on the images and the causes of these artefacts were investigated. The solutions will be discussed in this report. This emerging imaging technique can be used in tissue analysis such as disease management and biological process monitoring. By monitoring the birefringence, doctors or researchers are able to determine the structural properties of biological tissue, including engineered tissue. Future works includes investigating how other mechanical properties, such as compressive force, bending, torsion or shear force, affect birefringence. This approach will be of great benefit for diagnostic, therapeutic and for research purpose. This will definitely improve the quality of healthcare in the near future.