This PDF file contains the front matter associated with SPIE Proceedings Volume 10856, including the Title Page, Copyright information, Table of Contents, Author and Conference Committee lists.

Babies born before they reach full-term are at an increased risk of long-term complications. Currently, there are no accurate ways to predict when preterm birth (PTB) will occur. The cervix, which plays an essential role in maintaining a pregnancy to term, has to remain closed throughout gestation. However, for birth to occur, it has to shorten, soften and dilate. This crucial remodeling process appears to be linked to variations in the arrangement of collagen. Previous in vitro work using X-ray diffraction suggests that collagen fibers exhibit a preferential orientation in the non-gravid cervix: adjacent to the endocervical canal and in the outermost areas, fibers are mainly arranged in a longitudinal fashion whereas in the middle area they are circumferentially organized. We proposed using a potentially non-invasive imaging technique, polarization-sensitive optical coherence tomography (PS-OCT), to detect the changes in the collagen arrangement of human non-gravid cervix (n=10). Qualitatively, we found that PS-OCT is capable of discriminating between the three cervical regions. Quantitatively, the apparent birefringence of these areas is significantly different across all samples (p<0.05). As expected, apparent birefringence is much lower adjacent to the endocervical canal and in the outermost areas. PS-OCT also seems to be capable of estimating the thickness of the cervical epithelium. Our study, therefore, shows that PS-OCT can assess the microstructure of the human cervical collagen in vitro and holds the potential to help us better understand cervical remodeling prior to birth and develop more timely identification and prevention of PTB pending the development of an in vivo probe.

Oviduct and fallopian tube cilia serve as the primary means of tubal transport in the human reproductive system, with ciliated cells increasing from the isthmus to the infundibulum portions. Ciliary health is directly related to reproductive conditions such as tubal infertility and ectopic pregnancy. The ciliary beat frequency (CBF) changes over the ovarian cycle and is affected by both hormonal and neuronal stimuli, but is poorly understood in the natural environment due to limitations in current technology. Current techniques to measure ciliary beat frequency include high-speed video imaging, video microscopy, and optical methods, but access to minimally invasive in vivo imaging remains a challenge. A technology that enables the high-speed, high resolution, in-vivo imaging of the oviduct is essential for gaining insight into the natural ciliary activity in the oviduct, as well as the changes that take place with reproductive diseases. In this study, we report on the development of a spectrally-encoded interferometric microscopy (SEIM) system to visualize and analyze the spatial CBF of porcine oviduct cilia. We demonstrate the change in CBF from (7 to 12 Hz) that occurs under different temperature conditions from 23 to 29 degrees as well as the effects of lidocaine, where synchronized ciliary motion is disrupted. In addition, we examine the differences in ciliary activity between the infundibulum and ampulla portions of the fallopian tube. The results show that the SEIM system has the feasibility to detect CBF and ciliary acitivity in ex-vivo tissues with the potential to translate to minimally invasive in-vivo imaging.

Ovarian cancer is the deadliest gynecologic cancer due to predominantly late diagnosis. Early detection of ovarian cancer can increase 5-year survival rates from 40% up to 92%, yet no reliable early detection techniques exist. Multiphoton microscopy (MPM) is a relatively new imaging technique with tremendous potential for clinical diagnosis. A sub-modality of MPM is second harmonic generation (SHG) imaging, which generates contrast from anisotropic structures like collagen molecules, enabling the acquisition of detailed molecular structure maps. As collagen is known to change throughout the progression of cancer, MPM is a promising candidate for ovarian cancer screening.

While MPM has shown favorable results in a research environment, it has not yet found broad success in a clinical setting. One major obstacle is the quantitative analysis of the image content. Recently, the application of texture analysis to MPM images has shown success for characterizing the collagen content of the tissue, making it a prime candidate for disease screening. Unfortunately, existing work is limited in its application to ovarian tissue and few texture analysis approaches have been evaluated in this context.

To address these challenges, we applied texture analysis to second harmonic generation (SHG) and two-photon excited fluorescence (TPEF) images of a mouse model (TgMISIIR-TAg) of ovarian cancer. Using features from the grey-level co-occurrence matrix, we find that texture analysis of TPEF images of the ovary can differentiate between genotype with high statistical significance (p<0.001), whereas TPEF and SHG images of the oviducts (fallopian tubes) are most sensitive to age, and SHG images of the ovaries are most sensitive to reproductive status. While these results suggest that texture analysis is suitable for characterizing ovarian tissue health, further work is focused on developing a classification algorithm based on these features, and also to couple the results with a histopathological analysis.

Cancerous breast lesions are often stiffer than normal tissue and the stiffening of the tumor extra-cellular matrix (ECM) likely triggers neoplastic progression. Nevertheless, the course of ECM micro-mechanical alteration during cancer progression and its role in tumor aggression remains poorly understood. This is largely due to absence of imaging tool for micro-mechanical mapping of tissue at cellular scales. We have developed a novel optical tool, termed laser speckle microrheology (LSM) for imaging the micro-mechanical properties of tumor ECM. In this approach, tissue is illuminated by a coherent beam and back-scattered speckle patterns are collected by a high-speed camera. Spatio-temporal analysis of speckle fluctuations yields the map of viscoelastic modulus, G. We investigated the relationship between tumor stiffness measured by LSM and known markers of tumor progression, including histopathological grade and lymph-node status. De-identified specimens from 100 patients were evaluated. Analysis of Variance revealed that grades 1 and 2 carcinoma were significantly stiffer than normal fibro-adipose tissue (ḠgradeI = 830 µmPa, ḠgradeII = 715 µmPa, Ḡfibro-adipose = 238 µmPa, pGrade I vs fibroadipose=0.004, pGrade II vs fibroadipose =0.0006). Nevertheless, grade 3 tumors were significantly softer that grade 1 and 2 lesions (ḠgradeIII = 327 µmPa, pGrade I vs III=0.02, p Grade II vs III=0.0057). Moreover, lymph node positive tumors were softer than node negative ones (Ḡln+ = 355 µmPa , Ḡln-= 753 µmPa, p<0.0001). These findings open new avenues for understanding the link between ECM micromechanical properties and tumor progression towards identifying the mechano-biological mediators of malignancy, as potential therapeutic targets.

Cervical intraneoplasia (CIN), during its progression, shows an increased cell atypia and affects thicker epithelial structure. Photodynamic therapy (PDT) may constitute an attractive minimally invasive treatment technique. CIN mostly occurs at the squamous-columnar junction (SCJ) of the cervix, resulting in a challenge to achieve the aimed PDT uniform photosensitizer distribution and irradiation. The development of the clinical protocol and of the customized optical treatment probe is essential for an improved PDT response for CIN 1,2 and 3. Results of the developed instrumentation in an ongoing clinical study will be discussed.

Several studies have demonstrated that hormone-blocking therapies are more effective at reducing breast cancer risk in women who exhibit >10% reduction in breast density compared to women who had little or no density change, suggesting that breast density is a predictor of tamoxifen effectiveness. The goal of this prospective study was to assess whether diffuse optical spectroscopic imaging (DOSI) can measure the changes in breast composition under adjuvant tamoxifen treatment for breast cancer. The primary aim was to determine whether the change in the DOSI measurement of water correlates with the change in the MRI-derived quantitative measurement of breast density after 18 months of treatment in the contralateral normal breast of subjects receiving tamoxifen. Pre-menopausal subjects receiving tamoxifen (N=11 total, N=9 analyzable) and controls (N=18 total, N=15 analyzable) were enrolled and measured with co-registered DOSI and non-contrast MRI before, and 6, 12 and 18 months after beginning tamoxifen. Across all subjects, baseline MRI fibroglandular density correlated strongly with DOSI water (r=0.86, p<0.001), moderately with lipid (r=-0.63, p=0.001), and weakly with oxyhemoglobin (r=0.55, p=0.005) and deoxyhemoglobin (r=0.42, p=0.040) concentrations. Generalized estimating equation analysis revealed significant longitudinal differences between treated subjects and controls in the percentage change of MRI fibroglandular density (at 6 and 12 mo. timepoints), DOSI water (12 and 18 mo.), DOSI lipid (6, 12 and 18 mo.) Overall the data suggest that DOSI is sensitive to tamoxifen-induced changes in the human breast, and should be investigated further as a low-cost and low-risk means to predict response to tamoxifen treatment.

Real-time intra-operative resection margin assessment during breast-conserving surgery (BCS) is important to prevent incomplete tumor removal. Nowadays, in up to 37% of the women undergoing BCS, tumor positive margin are found after surgery. We test the feasibility of hyperspectral imaging to predict these positive margins in fresh lumpectomy specimens, to prevent incomplete tumor removal. Hyperspectral diffuse reflectance images (900-1700 nm) were collected on fresh lumpectomy specimens. These specimens were obtained from women undergoing primary BCS, that did not get neo-adjuvant treatment. To ensure hyperspectral images of the entire resection surface, we treated the specimen as a cube and imaged it from six different sides. Next, a SVM classification algorithm, which we developed and tested with a different dataset, was applied to these hyperspectral images to predict positive margins. Finally, we compared the margin assessment performed with hyperspectral imaging with histopathology, the gold standard for margin assessment. It was found that hyperspectral imaging could be used in the clinical workflow. First, data acquisition of the entire resection side was fast and took only 20 seconds per resection side. Second, with the earlier developed classification algorithm, data analysis could be performed in the operating theater in limited amount of time. Third, with hyperspectral imaging we were able to find 12 out of 13 positive resection sides. The one positive resection side that was missed contained a single malignant pocket smaller than 1 mm2. These preliminary findings make hyperspectral imaging a promising technique for resection margin assessment during BCS.

Objective and accurate surface measurements of the human breast are important for surgical planning. Traditionally, surgeons plan their procedures using radiographic images, but these images do not illustrate the breast in the surgical position (i.e. supine position). As a result, surgeons need to account for differences in breast size and shape, and surgical outcome is largely dependent on the surgeon’s experience. Previous studies have shown that scanning large-breasted patients in the standing position resulted in breast ptosis and high variability. A system capable of accurately scanning patients in the supine position is therefore desirable. The aim of this work was to develop a non-contact imaging system that can provide 3D information of each breast surface from patients in the supine position. Two structured-light surface scanners were combined using separate colour optical filters to minimize cross-talk between scanners. Test scans were collected from a 3D printed breast phantom in both the supine and standing positions. Scanning with blue and green filters simultaneously at two different angles eliminated shadowing artifacts compared to a single scanner reconstruction. The mean error distance between the phantom CAD model and point cloud measurements was 0.1 ± 0.1 mm for both standing and supine positions. Our system performed better than currently available commercial systems, which have accuracy of 0.5 - 1 mm.

Breast-conserving surgery (BCS) for treatment of breast cancer requires complete removal of the tumor. 20-30% of patients undergoing BCS require multiple surgeries due to cancer at or near the boundary (margin) of the excised tissue as assessed by postoperative histopathology. Intraoperative detection of involved margins could significantly reduce the number of patients requiring repeat surgeries. We built and deployed a portable optical coherence elastography system capable of rapid, 3D imaging of whole margins (46x46 mm) of excised breast specimens (wide local excisions, WLEs) removed during BCS. The system produces images of the microstructure and stiffness of the tissue using a phase-sensitive, compression-based elastography approach. The goal of this study was to determine the diagnostic accuracy (sensitivity and specificity), using this system, of OCT versus OCT plus micro-elastography for detecting cancer within 0.75 mm of the margin of the excised tissue. >70 women undergoing BCS were enrolled in the study. We scanned two margins from each fresh, intact surgical specimen within 2 hours of excision. We selected 10x10x0.75mm regions of interest (ROIs) from each margin scanned that are representative of the makeup of breast tissue. Post-operative histology, co-registered with the scans, was used as a gold standard, and a pathologist determined the tissue types present within each ROI based on corresponding histology. Recruitment for the study is complete, and a blinded reader analysis of one ROI from each margin is being performed by two surgeons, a pathologist, a radiologist, and an engineer. Results for sensitivity and specificity will be presented.

In 10 to 40% of breast cancer patients treated with breast conserving surgery, ductal carcinoma in situ (DCIS) or invasive carcinoma (IC) is present at the margin of the specimen. Diffuse Reflectance Spectroscopy (DRS) could potentially help the surgeon during surgery in avoiding these tumor positive resection margins. Here we assess the feasibility of DRS for discriminating healthy breast tissue from tumor. For this purpose, DRS measurements (400-1600nm) were obtained in 71 breast specimens. A custom-made grid was placed on top of a slice of the resection specimen to accurately correlate the DRS measurements with histopathology. To assess DRS for the discrimination between healthy and tumor tissue types, a support vector machine based classification algorithm was developed. A total of 1081 locations were included, of which 236 locations were considered homogenous (> 95% fat, connective tissue, IC, or DCIS) and 845 locations consisted of a mixture of tissue types. The spectra of pure DCIS locations were similar to the spectra of pure IC, suggesting that these tissue types could not be separated based on their spectra. In a first analysis it was found that locations of pure fat, pure connective, and pure tumor tissue (both DCIS and IC) could be discriminated with accuracies of 0.95, 0.95, and 0.79 respectively. Classification of mixture locations was more challenging. The accuracy for tumor detection depends on the amount of tumor present in the measurement volume. These results indicate that DRS can potentially be used for the detection of tumor at the resection margin.

For solid tumors, such as breast cancer, surgery is usually the treatment of choice. For these operations, it is of utmost importance to remove the whole tumor, since tumor-positive resection margins may result in recurrent disease and impaired overall survival. Current optical imaging techniques using endogenous contrast - e.g. diffuse reflectance spectroscopy or optical coherence tomography – for detection of breast cancers are limited to point measurements or long acquisition times. Broadband hyperspectral cameras, which provide a complete spectral fingerprint of the object at pixel level, are needed for two-dimensional imaging of the operative region. An ex vivo study was conducted to evaluate the feasibility of hyperspectral imaging for breast cancer detection. Fresh (<3 hours after surgery) resected breast cancer slices were imaged with a snapshot hyperspectral camera, which has 41 spectral bands, equally distributed in the visible and near-infrared (VIS-NIR) range (450 – 950 nm). Supervised analysis was performed by using the pathology annotations and unsupervised analysis was performed by using the hierarchical stochastic neighbour embedding (h-SNE) algorithm. So far, nine resected specimens, of which six invasive carcinomas and two (partially) mucinous carcinomas, were imaged. Spectral differences were found between the non-tumor, malign and benign regions on the resected specimens. Furthermore, automatic feature classification using h-SNE was possible in selected cases. Hyperspectral imaging showed great potential for discrimination of benign and malign breast tissue by using specific wavelengths bands in an ex vivo setting. Further analysis will be performed to determine whether it is possible to select tumor-specific wavelengths.

Cervical cancer is the fourth most common cancer in women worldwide. In low-income countries, it is a leading cause of death. Biop Medical has developed a portable multimodal optical imaging device for early screening and detection of squamous intraepithelial lesions (SIL). The device is a non-invasive probe which scans the cervix area and combines information from multiple optical modalities, for in vivo, real time detection of SIL. In this paper we present sample data acquired from 18 participants using the device in an in-vivo pilot study and present preliminary results of classification into low-grade and high-grade SIL.