A controlled internal electric field perpendicular to the skin-fat interface is selective in heating up fat and, consequently, has the ability to induce lethal thermal damage to subcutaneous adipose tissues while sparing overlying and underlying tissues. In vitro adipocyte cells are heat sensitive to thermal exposures of 50 and 45 degrees C on the order of minutes, 1 and 3 minutes, respectively. In vivo, 15 minutes thermal exposures to 43-45 degrees C result in a delayed adipocyte cellular death response-in this study, 9 days. The novel RF device presented herein effectively delivers therapeutic thermal exposures to subcutaneous adipose tissues while protecting epidermal and dermal layers.

As the frequency increases (i) the electric potential at the skin surface decreases from the center to the edge of the RF applicator; (ii) the difference between the power absorbed at the top and bottom of the subcutaneous fat layer increases; (iii) the difference between the power absorbed at the center and the periphery of the exposed subcutaneous fat volume also increases; and, consequently, (iv) the size of the heated subcutaneous fat volume decreases. Such a device when used in humans may allow for differential delivery of heat to varying fat thicknesses and anatomic areas.

We describe a new noninvasive microscopic near infrared reflectance hyperspectral imaging method for visualizing, in vivo, spatially distributed contributions of oxyhemoglobin perfusing the microvasculature within dermal tissue. Microscopic images of the dermis are acquired, generating a series of spectroscopic images formatted as a function of wavelength consisting of one spectral and two spatial dimensions; a hyperspectral image data cube. The data thus collected can be considered as a series of spatially resolved spectra. For data collection, images are acquired by a system consisting of a near infrared liquid crystal tunable filter (LCTF) and a Focal plane array detector (FPA) integrated with a microscope. The LCTF is continuously tunable over a useful near infrared spectral range (650-950 nm) with an average full width at half-height bandwidth of 6.78 nm. To provide high quantum efficiency without etaloning we utilized a back-illumination FPA with deep -depletion technology. A 30W halogen light source illuminates a dermal tissue area of approximately 18 mm in diameter. Reflected light from the dermal tissue is first passed through the microscope, the LCTF, and then imaged onto the FPA. The acquired hyperspectral data is deconvoluted using a multivariate least squares approach that requires at least two reference spectra, oxy-and deoxyhemoglobin. The resulting images are gray scale encoded to directly represent the varying spatial distributions of oxyhemoglobin contribution. As a proof of principle example, we examined a clinical model of vascular occlusion and reperfusion.

Background Acne lesion counting (ALC) is widely used to evaluate efficacy of new acne treatments. Although such evaluations are precise and highly discriminative, if assessed live, it can be a time‐consuming and intrusive measurement. Photographic assessment is a viable mode for ALCs and for training and/or qualifying evaluators. Aims The purpose of this study was to validate photographic methods for performing ALCs and to provide an objective measurement tool to train and/or qualify lesion count evaluators for deployment in both small‐ and large‐scale studies. Patients/Methods Assess accuracy and reliability of acne lesion counting via photographic methods in 8 subjects aged 16 to 40 years, with Fitzpatrick Skin Types I to VI. Frontal and 45°angle images taken at the single in‐clinic visit. Each subject underwent 3 counts per 4 evaluators: 1 set of live counts and 2 sets of photo counts. Intra‐evaluator and inter‐evaluator reliability measures for photo counts were evaluated using calculations of intraclass correlation coefficients (ICCs). Results Eight subjects (2 males and 6 females) age between 16 and 40 (min 16 years, max 25 years) diagnosed with facial acne vulgaris participated in the study. Fitzpatrick Skin Types ranged from III to V (three Type‐III, four Type‐IV, and one Type‐V). ICC values for intra‐evaluator reliability were found to be >0.95 for each evaluator, and ICC for inter‐evaluator reliability was found to be 0.98. Conclusions Photographic lesion count methodology is a reliable and accurate tool for objective measurement of ALCs and additionally, for training and/or qualifying evaluators.