Polarimetric imaging-based cancer bladder tissue's detection: A comparative study of bulk and formalin-fixed paraffin-embedded samples.

The polarimetry imaging technique as a promising technique for pathological diagnosis provides a handy tool for identifying and discriminating cancerous tissues. In this paper, the optical polarization properties of bulk bladder tissues without any further processing and Formalin-Fixed Paraffin-Embedded (FFPE) blocks of bladder tissues have been measured. The images of the Muller matrix for both normal and cancerous samples have been obtained and for quantitative analysis and to provide a more precise comparison, two methods have been applied; the Mueller matrix polar decomposition (MMPD), and the Mueller matrix transformation (MMT). The results have shown that some of the extracted parameters from these methods can be used to identify the microstructural differentiations between normal and cancerous tissues. The results revealed a good accord between the obtained optical parameters for bulk and FFPE bladder tissues. By measuring the polarimetric properties of the tissue right after resection, and also in the early stages of pathology (FFPE tissues), this method can be applied in vivo to perform an optical biopsy; Furthermore, this method has the potential to significantly shortens the duration of pathological diagnosis. The approach seems remarkable, simple, precise, and economical compared to the existing techniques for the detection of cancerous samples.

Rapid discrimination of Candida species based on optical diffraction pattern.

Candidiasis occurs mainly in immunocompromised patients. Rapid detection of Candida species can play a major role in the successful management of fungal infections and treatment monitoring. Detection and discrimination of five common strains of Candida species was performed using the optical elastic scattering diffraction pattern of their colonies. Using laser light with 632 nm wavelength and the designed optical system, optical diffraction patterns of C. albicans (ATCC12261), C. tropicalis (ATCC20336), C. glabrata (15545), C. guilliermondii (20216), and C. parapsilosis (22019) were recorded, processed and analyzed. The results of our study show that based on the different structure of Candida species and dissimilar structure of their colonies, the difference between acquired diffraction patterns are recognizable. In addition, through extraction of statistical feature of the diffraction pattern images and using classification techniques, the detection and discrimination could be performed in a semi-automatic way. The analysis of the colonies of five different Candida species by the optical diffraction patterns generated from the interaction of the laser with colonies' structures demonstrated that the technique had the potential to be applied for the detection and discrimination of various species.

Mueller matrix imaging of prostate bulk tissues; Polarization parameters as a discriminating benchmark.

The polarimetry imaging technique has provided a powerful tool for discriminating normal from cancerous tissues. In this paper, based on the backscattering Mueller matrix imaging of prostate bulk tissues, (received immediately after surgery without any further processing), we have extracted the characteristic features of the Mueller matrix images. In order to provide a quantitative and more accurate comparison, three different methods have been used; the Mueller matrix polar decomposition (MMPD), the Mueller matrix transformation (MMT) and the frequency distribution histograms (FDHs) and their central moment parameters. Comparing different tissues, the results of our study indicate that these methods provide the indicators for the characteristics of the microstructural features of the tissues. The indicators have the potential to distinguish between cancerous and healthy tissues. Determining the polarimetric characteristics of the tissue immediately after surgery and prior to the pathology, and the potential possibility of this technique to be used in vivo as an optical biopsy technique, can significantly reduce the cost and time of diagnosis of cancer.

Detection and Discrimination of Bacterial Colonies with Mueller Matrix Imaging.

The polarization imaging technique is a powerful approach to probe microstructural and optical information of biological structures (e.g., tissue samples). Here, we have studied the polarization properties of different bacterial colonies in order to evaluate the possibility of bacterial detection and discrimination. In this regard, we have taken the backscattering Mueller matrix images of four different bacteria colonies (i.e., Escherichia coli, Lactobacillus rhamnosus, Rhodococcus erythropolis, and Staphylococcus aureus). Although the images have the potential to distinguish qualitatively different bacterial colonies, we explored more accurate and quantitative parameters criteria for discrimination of bacterial samples; more specifically, we have exploited the Mueller matrix polar decomposition (MMPD),frequency distribution histogram (FDH), and central moment analysis method. The outcomes demonstrated a superior capacity of Mueller matrix imaging, MMPD, and FDH in bacterial colonies identification and discrimination. This approach might pave the way for a reliable, efficient, and cheap way of identification of infectious diseases.