Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Quantitative Phase Analysis in Lensless Digital Inline Holographic Microscopy(01. Izmir Institute of Technology, 2021) Tekin, Hüseyin Cumhur; Varlıklı, Canan; Tekin, Hüseyin Cumhur; Varlıklı, Canan; 03.01. Department of Bioengineering; 04.04. Department of Photonics; 03. Faculty of Engineering; 04. Faculty of Science; 01. Izmir Institute of TechnologyComputational imaging modalities replace the bulky, complex, and expensive optical components of traditional imaging procedures with numerical reconstruction steps. Digital holographic microscopy is one of the most prominent ones with the possibility of obtaining quantitative phase information by measuring the phase shift change caused by the refractive index of objects. In the lensless digital holographic microscopy system, a pinhole and a light-emitting diode are sufficient to create a holographic pattern on the camera sensor. Here, the optimization of a digital lensless inline holographic microscopy setup was performed to obtain optimal phase value. Also, to retrieve the lost phase information during the recording step, the numerical solution was performed with the single and multi-shot phase retrieval methods. Then, human breast adenocarcinoma (MDA-MB-231) and human myeloid leukemia (U937) cells were analyzed to obtain phase shift, perimeter, and circularity values. These parameters were used to obtain a quantitative differentiation model to replace the traditional labeling or visual confirmation steps with a direct analysis manner. The analysis of respective cells with the classification, object detection, and conditional generative adversarial models can be used directly with pre-trained weights to lessen the computational workloads. With this study, the quantitative analysis with lensless holographic microscopy setup was shown to be a label-free differentiation mechanism to separate cancer cells from monocytes cells which could be used for the early diagnosis of cancer. Also, the proposed method has the potential to be used to identify other cells with links to the diagnosis of different diseases.Master Thesis Development of Real Time Blood Vessel Imaging System for Early Diagnosis of Vascular Diseases(01. Izmir Institute of Technology, 2020) Gümüş, Abdurrahman; Gümüş, Abdurrahman; 03.05. Department of Electrical and Electronics Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyDisorders in the circulatory system may cause various diseases and tissue damage. The early detection of abnormalities in blood circulation has an important role in terms of treatment and also raising awareness of the patient. Vascular imaging methods used by today's technology are invasive, and/ or radiation-based. As an alternative to high-cost near infrared (NIR) vascular imaging devices in the market, a microcomputer-based, real-time, non-contact and safe vascular imaging system has been developed with low- cost. Due to the higher absorption coefficient of blood than skin and fat and also the differences in the spectra of oxy and deoxyhemoglobin in blood, the vascular structures were obtained using light at NIR region. A device, which uses NIR LED light operated at 850 nm, was designed using optical and electronic components. Image and video analysis were performed using OpenCV, which is an open-source software library, and data visualization libraries. Tests were carried out to optimize the best imaging conditions for the device. To be able to show abnormalities in the vascular structures and to test the effectiveness of the device, "diabetes", which can cause various vascular disease complications, was selected. Superficial vascular structures were observed in the near infrared images captured from people at different stages of this disease. As expected, the vessel images captured from the participants revealed deterioration in vascular structures in diabetic patients compared to healthy people. In order to make a clear inference about the accuracy of the images, it is necessary to compare them to the angiography images of the individuals and be interpreted by vascular surgery specialist.Master Thesis Craniofacial Computer Assisted Surgical Planning and Simulation(Izmir Institute of Technology, 1999) Ekin, Emine; Aytaç, İsmail Sıtkı; Aytaç, İsmail Sıtkı; 03.04. Department of Computer Engineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyIn this work, mainly, the first step of craniofacial surgical simulation and planning procedure, reconstruction of tomography images is investigated. The Direct Reconstruction techniques and algebraic methods are described in detailed mathematical formulations for both two and three-dimensional cases. And also a brief description of medical imaging techniques and the terminology of craniofacial surgical simulation and planning is given. In the last chapter the implementation details, the algorithms developed and some resulting images are given and the images are compared with respect to the used algorithms.