BRIAN WILLIAM POGUE

..Further research in this field can lead to advances in computer-aided diagnosis as well as the potential for online image enhancement in digital colposcopy...

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..4 +/- 1.4 days, and when PDT was given at the same time as radiation, the delay was 8.1 +/- 1.5 days. This observation indicates that the combined effect in the latter case was greater than additive (P = 0.049)...

..Raster scanned imaging appears to provide a more uniform and accurate way to quantify fluorescence signals from distributed tissues in vivo...

..Increasing measurement noise causes a need to constrain the minimum regularization parameter to higher values in order to achieve a minimum in the overall image MSE...

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..This signal was monotonically correlated to the deposited dose used here and could provide a direct dosimetric measure of PDT-induced cellular death in the tissue being treated...

..This imaging and data normalization procedure may be applied to cervical lesions of different grades, to determine if a quantitative estimate provides predictive value during the colposcopic diagnosis...

..The results suggest that hypoxic or poorly perfused vessels may be more susceptible to acute stasis than normoxic vessels in this treatment protocol...

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..Use of these new alternative forms becomes effective when the ratio of the number of imaging property parameters exceeds the number of measurements by a factor greater than 2...

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..The red light bleaching is found to increase the ability to accurately quantify PpIX fluorescence in vivo, but decreases the specificity of detection between tumor-bearing and nontumor-bearing groups...

..Precalibration of the algorithm through statistical evaluation of phantom studies may provide a better measure of the image accuracy than that implied by minimization of the standard objective function...

..Conclusions: This research suggests that accurate quantification of tissue photosensitizer levels and subsequent adjustment of light dose will allow for reduced subject variation and improved treatment consistency...

..4. A new linear convolution method of CNR calculation was developed for automated region of interest (ROI) detection...

..When both spatial and spectral priors were applied in a healthy volunteer, glandular tissue showed a higher [Hb(T)], water fraction, and scattering power compared to adipose tissue...

..These breast constituents vary significantly between individuals and can be altered because of changes in breast physiology or pathological state...

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..The ability to image reduced scattering coefficient spectra of bulk breast tissues exists, and so this data provides insight into how bulk imaging may be mapped over to predict factors related to the tissue ultrastructure...

..Finally, assuming a non-deformed breast shape for image reconstruction is shown to lead to poor quality images since the geometry of the breast is greatly altered, whereas using the correct deformed geometry produces the best images...

..The system and algorithms developed here should provide an optimal way to quantify regions with the goal of image-guided breast tissue spectroscopy within the MRI...

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..Three women with malignant breast tumors were studied. The addition of cw data at longer wavelengths increased the recovered contrast of water in the tumor region relative to surrounding tissue and allowed quantification of lipid...

..Optical transmitted fluorescent signal may add significant benefit for clinical cases of diffuse infiltrative growth pattern glioma tumors given sufficient optimization of the signal acquisition for each patient...

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..Interobserver variance performance in detecting objects in these images was low, suggesting that because of the low spatial resolution, detection tasks with NIR tomography is likely consistent between human observers...

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..CONCLUSIONS: Our results suggest that targeting both tumor vascular and cellular compartments by combining a long-interval PDT with a short-interval PDT can be an effective and safe way to enhance PDT damage to tumor tissue...

..This detection system and rodent model can be used for prospective dosimetry studies that focus on optimization of esophageal PDT...

..Each of these three major areas of image interpretation and analysis are reviewed in the context of medical imaging as well as how they are used to quantify the performance of diffuse optical imaging of tissue...

..Combined MR and near-infrared tomography provides fundamental molecular information about these tissue types with resolution governed by MR T1 images...

..This study presents a method to systematically analyze micro-heterogeneity as well as possible methods to increase delivery and homogeneity of photosensitizer within tumor tissue...

..Loss of endothelial barrier function can ultimately lead to tumor vascular shutdown and has significant implications in drug transport and tumor cell metastasis...

..These results support the hypothesis that temporal pharmacokinetic changes in the distribution of the photosensitizer between the tumor parenchyma and blood vessels can significantly alter the tumor target of PDT...

..This approach is expected to improve recovery of abnormalities within the breast, as the inclusion of structural information increases the accuracy of recovery of embedded heterogeneities, at least in phantom studies...

..Finally, our research suggests that the tools or methods we are studying for quantifying PS levels and tissue damage are necessary for the understanding of PDT effect and therapeutic ratio in experimental in vivo tumor research...

..The ability to image thick tissue and the capacity to image periodic changes in absorption makes this design well suited for tracking thick tissue hemodynamics in vivo during MR or CT imaging...

..Specifically, fluorescence measurements are favorable if background drug concentrations are below 135-200 nM for LuTex and 25-50 nM for ICG, while absorption measurements are more sensitive above these ranges...

..This multimodality imaging system will have a wide range of applications in preclinical cancer research ranging from studies of the tumor microenvironment and treatment efficacy for emerging cancer therapeutics...

..Future work includes the minimization of bias (artifacts) on the periphery of electrical impedance spectroscopy images to improve cross modality correlation and implementation of the multimodality diagnosis for breast cancer detection...

..Image guidance is necessary for accurate positioning, and multi-plane acquisition can improve this accuracy...

..These results indicate that iron chelation therapy could significantly increase delta-ALA-induced PpIX fluorescence in malignant gliomas, pointing to a potential role of iron chelation therapy for more effective FGR of brain tumors...

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..This report demonstrates the diagnostic potential of magnetic resonance imaging (MRI)-coupled fluorescence molecular tomography (FMT) to determine epidermal growth factor receptor (EGFR) status in brain cancer...

..Pilot in-vivo data are also presented, showing recovery of subcutaneous tumor tissue values of protoporphyrin IX in a subcutaneous U251 tumor, which has less fluorescence than the skin...

..Examples of clinical systems under research and development are shown...

..In addition, the technique provides a unique approach to measuring tissue elastic changes in vivo in the female breast and may offer a new method for dynamic contrast imaging based on elasto-optical measurements...

..Bulk fluorescence spectroscopy techniques performed as well as most imaging techniques, suggesting that complex imaging algorithms may be unnecessary to diagnose EGFR status in these tissue volumes...

..These changes represent potential diagnostic indicators, which can be assessed to characterize breast tumors...

..No statistically valid correlations were found between the applied pressure and the changes in tissue oxygen saturation (S(t)O(2)) or water percentage (H(2)O) across the range of BMI values studied...

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..35 mm diameter inclusion with an absorption coefficient of 0.01 mm(-1) and a reduced scattering coefficient of 1.5 mm(-1) that is moving along a circular path inside a 1% Intralipid solution...

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..Consequently, it seems that multitargeted photoimmunotherapy should also be useful against cancers that overexpress other receptors...

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..The study indicates that use of L1 in tumors with a lower innate production of PpIX with ALA alone may be the most productive approach to this combined delivery...

..This review is an attempt to indicate which sets of phantoms are optimal for specific applications, and provide links to studies that characterize main phantom material properties and recipes...

..Accurate quantification was obtained with a mean error of 7.7% for oxygen saturation and 6.2% for total hemoglobin, with minimal cross talk between different parameters...

..The results suggest that provided the refractive index of breast tissue is approximately 1.3-1.4, their exclusion will have minimal effect on the reconstructed images...

..However, increases in tissue curvature and/or the addition of prior information are expected to improve the linearity of the response. The potential for this type of imaging technique to serve as a surgical guide is highlighted...

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..The steady-state broadband CCD system has the potential to provide accurate chromophore imaging without the technological complexity of time- or frequency-domain systems...

..The increased sensitivity of this technique may render it useful to guide the surgeon or pathologist where to sample pathology for microscopic assessment...

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