This study investigated the combination of two contrast agents for ex vivo cancer detection in breast tissues. Samples were stained with molecular marker pH Low Insertion Peptide (pHLIP) conjugated with fluorescent dye Alexa532 (pHLIP–Alexa532), and intravital stain Methylene Blue (MB), and imaged with a high-resolution confocal microscope. Resulting images display cellular morphology with staining patterns mimicking Hematoxylin and Eosin histopathology and show promise for the method used as a tool for breast cancer detection in biopsies or intraoperatively.

Structured illumination microscopy provides a compelling solution to location inaccuracy a in core-needle breast biopsy procedures. Fluorescent H&E analog dyes and dual-channel SIM imaging were utilized to create an digital pathology image analogous to a standard histology within minutes for point of care pathology. This study validated SIM’s ability to generate an image for on-site pathology validation of sample quality which minimizes the risk of a repeat procedure. Diagnoses from the diagnostic-quality SIM images were also proven to align with diagnoses obtained by standard histological processing of the same sample.

Blood flow measurement in deep tissue is important because the circulatory system transports oxygen and nutrition to the tissue and removes carbon dioxide out from the tissue. Several non-invasive optical methods were developed for blood flow measurement in deep tissue, such as diffuse correlation spectroscopy (DCS) and diffuse speckle contrast analysis (DSCA). In this paper we will introduce a new speckle-based method for fast blood flow measurement in deep tissue: diffuse speckle pulsatile flowmetry (DSPF). By using a multi-mode fiber for speckle pattern detection, DSPF achieves high blood flow measurement rate of 300 Hz. It has one of the fastest measurement rates of blood flow among non-invasive modalities.

The high sensitivity of the polarized light to the subtle variations in the tissue structure makes it a promising tool for the detection and staging of cancer. Here, we present the results of the imaging and analysis of the formalin-fixed and paraffin-embedded samples of breast carcinoma at different stages with the circularly polarized light. The degree of the polarization was confirmed to be the most sensitive parameter indicating the malignancy of the tumor. The obtained measurement data has been depicted on the Poincare sphere to highlight the changes in the polarization caused by the interaction with the tissue. Cluster analysis based on the k-means algorithm has been performed to implement the automated classification of the obtained data.

White light endoscopy is the gold standard endoscopic screening technology; however, early lesion detection is low with this modality. Narrow-band imaging provides vascular enhancements using blue and green bandwidths for contrasting illumination. We propose hyperspectral imaging to increase the number of contrasting illumination bands to 8-16 for potential image enhancements. Here, we report on performance metrics of a previously developed prototype LED-based spectral light source including: improved illumination transmission throughput, resolution and color response. Results show comparable resolution to the gold standard and baseline color validation for hyperspectral endoscopy.

We introduce a novel technique, “optical barcoding”, which enables us to repeatedly extract the 2D OCT slice from a 3D OCT volume that corresponds to a given H&E tissue section, with high alignment precision of 25 microns. Our method is based on marking a specific geometric pattern that is preserved through the standard histological process and encodes all orientation, position and scaling information about how the section was cut. We demonstrate the robustness of our novel technique by collecting hundreds of high-quality OCT-H&E image pairs from more than 30 different human skin samples that were collected during Mohs surgery.

Non-linear endoscopic imaging probes allow for in-vivo, label free tissue histology and thus bring tumour treatment to a new level providing accurate, real time diagnostics. Here we present an endomicroscopic imaging probe for coherent anti-Stokes Raman scattering (CARS) imaging based on a fiber piezo scanner at the distal side of the probe. One of the main hurdles in the implementation of CARS imaging in all-fiber solutions is the generation of a background four-wave-mixing (FWM) signal within the delivery fiber by the Stokes- and pump lasers involved in the process of generation of the nonlinear image. We developed and realised a novel solution based on a silica double-core double-clad (DCDC) fiber, which allows a separate guiding of the exciting Stokes- and pump laser radiation in two separate cores of the delivery fiber. The optical design of the endoscopic probe allows perfect overlap and focusing of the Stokes and pump lasers across the full field of view of the probe.

We developed a high-precision multispectral fluorescence lifetime imaging microscopy (FLIM) for label-free immune-histologic imaging of atherosclerotic plaques. With images of fluorescence lifetimes and intensity ratios between different channels, we could characterize various plaque components of coronary arteries that are related to immunohistochemistry results. Correlative FLIM-immunohistochemistry validation revealed significant associations between plaque components and multispectral FLIM parameters. The machine learning algorithm, trained with co-registered FLIM-immunohistochemistry datasets, allowed automated visualization of multiple atherosclerotic components from FLIM image of an unstained section. We anticipate that the multispectral FLIM can be widely used to assess biochemical components of various biological tissues, including atherosclerotic plaques.

Skin cancer is one of the leading causes of mortality in dogs. In this work, we acquired ex-vivo optical coherence tomography (OCT) images and Raman spectra (785 nm excitation) of 40 canine skin tumors: mast cell tumors (MCT), lipomas, and sarcomas. MCTs and sarcomas appeared to be highly dispersive, lacking ordered microstructure. Lipomas showed a specific texture pattern. While MCTs and sarcomas exhibited a loss of some major Raman spectral bands, lipid tissue-specific bands in lipomas were easily detectable. Our results show the potential of combined OCT and Raman spectroscopy for the characterization of canine skin and subcutaneous tumors ex-vivo.

Review of the design, development and evaluation of special fiber optic probes, to combine key methods: Raman scattering, Mid IR-absorption, Diffuse NIR-reflection and fluorescence, enables to increase sensitivity, specificity and accuracy to determine different types of biotissues in-vitro: e.g. fluorescence and combi Fluo/ Mid IR-absorption; Raman and NIR-reflection. 2 other combi-methods were tested ex-vivo for: a) Oral cancer – HW-Raman + Fluorescence; b) Colorectal Cancer – Fluorescence + Near-Infrared Spectroscopy. Chemometric treatment of spectral data obtained with combi-fiber probes enables to improve discrimination capability vs the single methods and shows the capability to use multi-spectral fiber spectroscopy in biomedicine.

The molecular changes due to malignancy as a perturbation to the Raman scattering may cause Fano resonance, which leads to variations in the lineshape of Raman peaks. We analyzed visible resonance Raman (VRR) spectra of three breast cancer cell lines with different malignancy. The fitted Fano coupling parameter, peak position and linewidth were compared among the three cell lines. The results using the compositive peak that encloses 2886 and 2932 cm-1 are presented, showing the three cell lines are significantly different. This novel technique may be promising as an optical biopsy technique for cancer diagnosis.

Recent reports pointed out that the application of optical spectroscopy in the field of liquid biopsy has aroused great interest among researchers and demonstrated the potential of its clinical application. We report a preliminary investigation on the visible resonance Raman (VRR) spectra of human brain blood liquid collected from the scalp and around the meningeal tumor during surgery by a portable VRR analyzer in vivo. Six sets of biochemical fingerprints were found. These results indicate that if VRR spectroscopy technology is combined with polymerase chain reaction (PCR)/or genetic molecular biomarker methods, it will greatly increase the possibility of clinical application.

Oral cancer has a poor five-year survival rate due to a lack of effective non-invasive diagnostic techniques. In this regard, fluorescence polarization gating technique has been adopted to estimate the relative variation of tryptophan in different layers of tissue. Our result finds out that the integrated intensity, peak position, and line width of tryptophan in different layers of tissue have high statistical significance in discriminating oral cancer tissue.

We report a photonic implementation of the Reservoir Computer (PhRC) for sensing application. The kernel of the PhRC will be in the form of chaotic microcavity on a photonic crystal cavity platform designed to discriminate different analytes. The discrimination is achieved by recognising the unique temporal signal signature arising from the chaotic kernel in the presence of different analyte. The unique temporal signature is obtained exploiting the sensitive to the initial-condition response of a billiard shaped microcavity. This is noted that the new discrimination approach reported is performed directly on the temporal signal, in contrast to the conventional spectral fingerprinting.

We demonstrate a software application that allows to interface with commercially available spectral filter array cameras, embed an imaging pipeline implementation, and permits to manipulate and visualise available bands in real time to enhance tissue and physiologic feature observations for medical diagnostics.

There is a demand for accurate and miniaturized diagnostic biomedical devices. Optical spectroscopy techniques have been used for decades to provide structural and chemical information. Many techniques require bulky equipment and are limited to laboratory measurements, some have low sensitivity. Mid-infrared (MIR) spectroscopy measures the absorption of fundamental molecular vibrations and is used to identify and quantify biomolecular constituents. By combining fiberoptics with MIR spectroscopy, difficult locations can be accessed. Signal-enhancement methods can reduce challenges due to water absorption. Recent component developments for the MIR open up new applications. Further development of biomedical devices based on MIR spectroscopy are promising.

Early diagnosis of Triple Negative Breast Cancer (TNBC) is essential to implementing early, life-saving treatment before the development of metastases. Traditional methods for detecting TNBC is difficult, being both tedious and vulnerable to false positive results. Here we combine optical imaging techniques—deuterium probed resonance Raman spectroscopy (RRS) and multiphoton fluorescence (MPF) to detect TNBC metabolism in early stage. These hallmarks such as glucose and lipid metabolism are revealed through chemical bond vibrational modes with RRS and morphological changes with MPF at subcellular scale.

Isotope Probed Stimulated Raman Scattering microscopy (ip-SRS), resonance Raman spectroscopy (RRS), and two photon excitation fluorescence (TPEF) microscopy can reveal spatial biomolecular information useful in distinguishing cell subtypes and phenotypic states. In the present study, we used deuterated metabolites to probe their enzymatic incorporation during scavenging and de novo biosynthesis of macromolecules in breast cancer with SRS, as well as their effects on cellular respiration and organelle health by imaging the NADH and flavin pools and labeled organelles with TPEF. This will enhance diagnostic efficacy and illustrate specific biochemical effects of manipulated nutrition and targeted therapies.