This PDF file contains the front matter associated with SPIE Proceedings Volume 8220, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.

A portable near infrared scanning polarization imaging unit with an optical fiber-based rectal probe, namely Photonic Finger, was designed and developed o locate the 3D position of abnormal prostate site inside normal prostate tissue. An inverse algorithm, Optical Tomography using Independent Component Analysis (OPTICA) was improved particularly to unmix the signal from targets (cancerous tissue) embedded in a turbid medium (normal tissue) in the backscattering imaging geometry. Photonic Finger combined with OPTICA was tested to characterize different target(s) inside different tissue medium, including cancerous prostate tissue embedded by large piece of normal tissue.

Angular Domain Spectroscopic Imaging (ADSI) is a novel technique for the detection and characterization of optical contrast abnormalities in ex-vivo breast tissue samples based on spectral characteristics. The imaging system employs a spatial filter called an angular filter array to reject scattered photons traversing a sample. The system employs an imaging spectrometer to capture and discriminate the largely remaining quasi-ballistic photons based on spatial position and wavelength. Spectral data were obtained from samples obtained from two patients, one sample contained invasive mammary carcinoma, and the other one contained normal fat and fibrous tissue. Principal component analysis using transmission absorption spectra obtained with ADSI was able to differentiate tumor versus normal tissue regions.

Accurate diagnosis of premalignant or malignant oral lesions depends on the quality of the biopsy, adequate clinical information and correct interpretation of the biopsy results. The major clinical challenge is to precisely locate the biopsy site in a clinically suspicious lesion. Dips due to oxygenated hemoglobin absorption have been noticed at 545 and 575 nm in the diffusely reflected white light spectra of oral mucosa and the intensity ratio R545/R575 has been found suited for early detection of oral pre-cancers. A multi-spectral diffuse reflectance (DR) imaging system has been developed consisting of an electron multiplying charge coupled device (EMCCD) camera and a liquid crystal tunable filter for guiding the clinician to an optimal biopsy site. Towards this DR images were recorded from 27 patients with potentially malignant lesions on their tongue (dorsal, lateral and ventral sides) and from 44 healthy controls at 545 and 575 nm with the DR imaging system. False colored ratio image R545/R575 of the lesion provides a visual discerning capability that helps in locating the most malignant site for biopsy. Histopathological report of guided biopsy showed that out of the 27 patients 16 were cancers, 9 pre-cancers and 2 lichen planus. In this clinical trial DR imaging has correctly guided 25 biopsy sites, yielding a sensitivity of 93% and a specificity of 98%, thereby establishing the potential of DR imaging as a tool for guided biopsy.

Near infrared (NIR) diffuse reflectance spectroscopy is a rapid noninvasive spectroscopic technique extensively used in the field of biomedicine. The main challenges of the NIR spectroscopy lie in the analysis of the acquired spectral information, requiring prior knowledge on the influence of various tissue parameters on the spectra. In this paper, we focus on the influence of pressure on the soft tissues NIR spectra. The existing studies based on static measurements showed that pressure tends to decrease the diffuse reflectance of the soft tissue. The purpose of this study was to further analyze the effects of static and in particular dynamically changing pressure on the soft tissue diffuse reflectance properties and assess its potential for tissue classification. For this purpose, a custom real-time system for rapid acquisition of NIR diffuse reflectance spectra of tissue under controlled static or dynamically changing pressure was developed. The study was conducted using porcine ribs and porcine liver (in vitro) tissue samples and human skin (in vivo). The acquired spectra were preprocessed by mean centering or standard normal variate and analyzed by Principal Component Analysis (PCA). A polynomial function was used to model the first three calculated scores as a function of the applied pressure. It was found, that the median values of the calculated polynomial coefficients were significantly different for all the samples, indicating reflectance changes due to the applied pressure could be used for classification of biological tissues.

Histo pathological examination is the gold standard to discriminate between benign and malignant growth of tissue. But this is invasive and stressful. Hence many non invasive imaging techniques, such as CT, MRI, PET, etc are employed, each having certain advantages and disadvantages. In this context optical biopsy is a newly emerging technique, since it employs non-ionizing radiation like light or laser, which could be shined directly or launched through optical fiber to reach any part of the body. This paper reports results of time resolved emission spectra of 24 excised tissue sample (normal control=12; benign=4; malignant=8) of breast and prostate, employing a 390nm, 100 fs, Ti-Sapphire laser pulses. The fluorescence decay times were measured using streak camera and fitted for single and bi- exponential decays with reliability of 97%. Our results show the distinct difference between normal, benign and malignant tissues attributed changes of NADH and FAD levels.

A prototype instrument developed to provide simultaneously ordinary visual endoscopy together with NIR autofluorescence imaging via parallel image acquisition is demonstrated. The two images are recorded concurrently, and the instrument interfaces with any ordinary endoscope. Preliminary results of a pilot study focused on imaging of bladder tumors in vivo using this instrumentation are presented. The experimental results demonstrate the capabilities of this instrumentation design, imaging methodology and define the current limitation for further development of the system.

In this paper, we report an intraoperative approach by combining optical coherence tomography (OCT) and position detection to detect and characterize ovarian cancers. A total of 18 ovaries were studied ex vivo. Based on histopathology result, they were classified into normal and malignant groups, respectively. On average positron count rate of 8.0-fold higher was found between malignant and normal ovaries. OCT imaging of ovaries revealed many detailed morphologic features that could be potentially valuable for detecting early malignant changes in ovarian tissue. Optical scattering coefficients of these ovaries were estimated from OCT A-lines. Normal ovarian tissue showed higher scattering coefficient than that of malignant ovarian tissue. Using a threshold of 2.00 mm^-1 for all ovaries, a sensitivity of 100% and a specificity of 100% were achieved. This initial data shows our intraoperative probe based on OCT and positron detection has a great potential for ovarian cancer detection and characterization.

In this study, a portable Y-type fibreoptic fluorescence spectroscopy measurement system was used to evaluate the freshness of eight cobias (Rachycentron canadum). The results showed that the ratio of fluorescent intensity, which F₄₈₀ nm/F_exci+50 nm was belong with the range of collagen type I and type V characteristic spectra, was positive correlated to the frozen time by hours. It was a strong approach to be a potential index for differentiating the fish freshness during delivery process. Besides, the different pattern results of dorsum and abdomen were shown in this study. In further, fibreoptic fluorescence spectroscopy could be a way not only to measure and quantify the freshness of different fish body but also to verify the level of taste.

A compact Stokes shift and fluorescence spectroscopy (S3) LED device with no moving parts is presented. This device can be used diagnostically for the identification of the native biomolecules within cancerous tissue samples. This S3-LED ratiometer unit measures both the emission and absorption spectra of key native organic biomolecules within a tissue sample by using multiple wavelength LEDs (light emitting diodes) coupled to an optical fiber. Thus, an optical fingerprint of the sample can be obtained. This technique could be used to distinguish benign and malignant tissues, and to check for residual or recurrent carcinoma after treatment, thus reducing the necessity of second biopsies. The S3-LED ratiometer unit was tested in vitro on human breast malignant and normal paired tissue samples.

Gleason score is the most common method of grading the virulence of prostate malignancy and is based on the pathological assessment of morphology of cellular matrix. Since this involves the excision of the tissue, we are working on a new, minimally invasive, non contact, procedure of spectral diagnosis of prostate malignancy. In this preliminary in vitro study reported here, we have analyzed 27 tissue samples (normal control =7: benign=8: malignant =12) by Stokes' shift spectra (SSS) to establish a one- to- one correlation between spectral grading and Gleason grading.

When translating new imaging modalities into the clinic, one can expect new discoveries. Owing to the high photon count rates, near-infrared fluorescence (NIRF) offers exquisite sensitivity and high temporal resolution that enable new insights into human disorders. Herein, the physics of NIRF are highlighted and compared to those involved in nuclear medicine techniques. The initial application of investigational NIRF involving characterization of the lymphatics in humans and animal models of human disease yields discoveries not otherwise attainable with conventional imaging.

Multimodal nonlinear imaging constitutes a contemporary approach to investigate the morphochemistry of complex samples noninvasively and without administration of external labels. Here we discuss our recent success in jointly using various nonlinear microspectroscopic approaches such as coherent anti-Stokes Raman scattering (CARS), two-photon fluorescence (TPF) and second-harmonic generation (SHG) to study the chemical composition of surgically removed tissue sections from laryngeal carcinoma. In particular it will be shown how multimodal nonlinear imaging can be employed to study the structural and chemical development of disease formation as well as to monitor the clinically important aspect of tumor boundary detection.

The care of modern traumatic war wounds remains a significant challenge for clinicians. Many of the extremity wounds inflicted during Operation Enduring Freedom and Operation Iraqi Freedom are colonized or infected with multi-drug resistant organisms, particularly Acinetobacter baumannii. Biofilm formation and resistance to current treatments can significantly confound the wound healing process. Accurate strain identification and targeted drug administration for the treatment of wound bioburden has become a priority for combat casualty care. In this study, we use vibrational spectroscopy to examine wound exudates for bacterial load. Inherent chemical differences in different bacterial species and strains make possible the high specificity of vibrational spectroscopy.

Time-resolved fluorescence emission from normal breast tissue, benign and malignant breast tumors were measured using excitation of 100 fs pulses at 310nm. Fluorescence relaxation decay parameters were extracted from the measured temporal emission profiles. The decay times and amplitudes of fast and slow profiles of malignant tissues were different from normal and benign tissues, which allows the malignant tumor to be separated from non-malignant breast tissue. The differences between the decay times of slow and fast component can be explained by tissue structure changes during breast cancer evolution.

Cancer cells display high rates of glycolysis even under normoxia and mostly under hypoxia. Warburg proposed this effect of altered metabolism in cells more than 80 years ago. It is considered as a hallmark of cancer. Optical spectroscopy can be used to explore this effect. Pathophysiological studies indicate that mitochondria of cancer cells are enlarged and increased in number. Warburg observed that cancer cells tend to convert most glucose to lactate regardless of the presence of oxygen. Previous observations show increased lactate in breast cancer lines. The focus of this study is to investigate the relative content changes of lactate and mitochondria in human cancerous and normal breast tissue samples using optical spectroscopic techniques. The optical spectra were obtained from 30 cancerous and 25 normal breast tissue samples and five model components (Tryptophan, fat, collagen, lactate and mitochondrion) using fluorescence, Stokes shift and Raman spectroscopy. The basic biochemical component analysis model (BBCA) and a set of algorithm were used to analyze the spectra. Our analyses of fluorescence spectra showed a 14 percent increase in lactate content and 2.5 times increase in mitochondria number in cancerous breast tissue as compared with normal tissue. Our findings indicate that optical spectroscopic techniques may be used to understand Warburg effect. Lactate and mitochondrion content changes in tumors examined using optical spectroscopy may be used as a prognostic molecular marker in clinic applications.