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OBJECTIVE -Foot ulceration is a serious complication of diabetes, and new techniques that can predict wound healing may prove very helpful. We tested the ability of medical hyperspectral technology (HT), a novel diagnostic scanning technique that can quantify tissue oxy-and deoxyhemoglobin to predict diabetic foot ulcer healing.RESEARCH DESIGN AND METHODS -Ten type 1 diabetic patients with 21 foot ulcer sites, 13 type 1 diabetic patients without ulcers, and 14 nondiabetic control subjects were seen up to 4 times over a 6-month period. HT measurements of oxyhemoglobin (HT-oxy) and deoxyhemoglobin (HT-deoxy) were performed at or near the ulcer area and on the upper and lower extremity distant from the ulcer. An HT healing index for each site was calculated from the HT-oxy and -deoxy values.RESULTS -Hyperspectral tissue oxygenation measurements observed changes in tissue immediately surrounding the ulcer when comparing ulcers that heal and ulcers that do not heal (P Ͻ 0.001). The sensitivity, specificity, and positive and negative predictive values of the HT index for predicting healing were 93, 86, 93, and 86%, respectively, when evaluated on images taken at the first visit. Changes in HT-oxy among the three risk groups were noted for the metatarsal area of the foot (P Ͻ 0.05) and the palm (P Ͻ 0.01). Changes in HT-deoxy and the HT healing index were noted for the palm only (P Ͻ 0.05 and P Ͻ 0.01, respectively).CONCLUSIONS -HT has the capability to identify microvascular abnormalities and tissue oxygenation in the diabetic foot and predict ulcer healing. HT can assist in the management of foot ulceration. Diabetes Care 30:903-910, 2007D iabetic foot ulceration (DFU) remains a serious problem, as 15% of all diabetic patients are expected to be affected with the complication during their lifespan (1). Infected and/or ischemic DFU accounts for ϳ25% of all hospital stays among diabetic patients, while foot ulceration precedes 85% of lowerextremity amputations (2). Currently, large multicenter studies (3-5) have reported that the healing rate of DFU over a 12-to 20-week period lies between 30 and 60%. Early identification of patients who will go on to fail to heal an ulcer can be of particular help, as it can allow the physician to make the right choice of treatment between a conservative and aggressive path. Pathways can be developed to streamline patient care and to apply new, expensive therapies only in patients who need them.The evaluation of neuropathy, peripheral vascular disease, presence of infection, and the depth of the ulcer are standard procedures for the management of DFU (6). However, none of the above measurements can predict wound healing. The only method that has previously been shown to predict wound healing is the measurement of changes in the ulcer area over a 4-week period of intensive care (7). However, the positive predictive value of this technique is only 58%, while the negative predictive value is 91%. Additionally, using the measurement-of-change method requires sequential patient examination...

Abstract. Knowledge of the dynamic topography at Earth's surface caused by sublithospheric density contrasts would provide crucial constraints on models of mantle dynamics. We calculate global models of this dynamic topography by subtracting from the observed topography estimates of the topography caused by assumed isostatically compensated density variations in the crust, the oceanic lithosphere, and the continental tectosphere. We also calculate the isostatic geoid anomaly that would result from these compensated near-surface density anomalies.Because there is controversy about the thermal structure of old oceanic lithosphere, we investigate two models of the cooling of the oceanic lithosphere (half-space and plate) and calculate the effect of each on the inferred dynamic topography. Peak amplitudes of dynamic topography fi, om sublithospheric sources expanded to spherical harmonic degree 6 are approximately ñ 1 km. We estimate the uncertainties in the calculated dynamic topography and geoid by combining the errors in the data and systematic errors. To obtain the spectral coefficients of the fields, we use weighted least squares inversions. The calculated dynamic topography arising from sublithospheric sources, residual geoid, and errors associated with these fields can be used in studies of mantle dynamics.

Introduction. Adequate evaluation of breast tumor resection at surgery continues to be an important issue in surgical care, as over 30% of postoperative tumors recur locally unless radiation is used to destroy remaining tumor cells in the field. Medical Hyperspectral Imaging (MHSI) delivers near-real time images of biomarkers in tissue, providing an assessment of pathophysiology and the potential to distinguish different tissues based on spectral characteristics.Methods. We have used an experimental DMBA-induced rat breast tumor model to examine the intraoperative utility of MHSI, in distinguishing tumor from normal breast and other tissues. Rats bearing tumors underwent surgical exposure and MHSI imaging, followed by partial resection of the tumors, then MHSI imaging of the resection bed, and finally total resection of tumors and of grossly normal-appearing glands. Resected tissue underwent gross examination, MHSI imaging, and histopathological evaluation.Results. An algorithm based on spectral characteristics of tissue types was developed to distinguish between tumor and normal tissues. Tissues including tumor, blood vessels, muscle, and connective tissue were clearly identified and differentiated by MHSI. Fragments of residual tumor 0.5-1 mm in size intentionally left in the operative bed were readily identified. MHSI demonstrated a sensitivity of 89% and a specificity of 94% for detection of residual tumor, comparable to that of histopathological examination of the tumor bed (85% and 92%, respectively).Conclusion. We conclude that MHSI may be useful in identifying small residual tumor in a tumor resection bed and for indicating areas requiring more extensive resection and more effective biopsy locations to the surgeon.