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Red Bank, NJ, United States

Bargo P.R.,Johnson and Johnson CPPW | Seo I.,Johnson and Johnson CPPW | Kollias N.,Johnson and Johnson CPPW
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2010

Measurement of cutaneous microcirculation is of great importance for clinical evaluations as many biological processes (i.e. inflammation) activate superficial vessels. Diffuse Reflectance Spectroscopy (DRS) is a widely used method to assess cutaneous microcirculation since it is based on the spectral characteristics of skin chromophores, particularly the strong absorption bands of blood in the visible spectral range. However, the DRS system only provides a snapshot of the blood content in tissue from the reflectance detected at a single exposure time, and it fails to demonstrate dynamic changes of blood flow inside the tissues. In the present study, a prototype system for functional DRS (fDRS) has been developed for the sequential acquisition of multiple reflectance spectra in the visible range at sub-second intervals. Twelve healthy subjects with skin phototype I-III were recruited for a UV skin phototest where the subject's back was exposed to an increasing dose of solar-simulated radiation at a maximum of 3 minimum erythema dose (MED). Evaluations included conventional DRS, functional DRS, and a laser Doppler flowmeter/imaging system. In a frequency analysis results, there were two distinctive frequency components. A low-frequency component was found near 0.03-0.1 Hz, and another high-frequency component near 0.9-1.2 Hz which is synchronous with heart pulsations. The magnitude of the high-frequency and the steady-state components of the fDRS signal increased with increase in exposure dose. These results demonstrate the potential of this technique for noninvasive assessment of cutaneous microcirculation. © 2010 Copyright SPIE - The International Society for Optical Engineering. Source


Ruvolo Jr. E.C.,Johnson and Johnson CPPW | Bargo P.R.,Johnson and Johnson CPPW | Dietz T.,Endo Surgery Inc. | Scamuffa R.,Endo Surgery Inc. | And 3 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2010

In rhytidectomy the postoperative edema (swelling) and ecchymosis (bruising) can influence the cosmetic results. Evaluation of edema has typically been performed by visual inspection by a trained physician using a fourlevel or, more commonly, a two-level grading (1). Few instruments exist capable of quantitatively assessing edema and ecchymosis in skin. Here we demonstrate that edema and ecchymosis can be objectively quantitated in vivo by a multispectral clinical imaging system (MSCIS). After a feasibility study of induced stasis to the forearms of volunteers and a benchtop study of an edema model, five subjects undergoing rhytidectomy were recruited for a clinical study and multispectral images were taken approximately at days 0, 1, 3, 6, 8, 10, 15, 22 and 29 (according with the day of their visit). Apparent concentrations of oxy-hemoglobin, deoxy-hemoglobin (ecchymosis), melanin, scattering and water (edema) were calculated for each pixel of a spectral image stack. From the blue channel on cross-polarized images bilirubin was extracted. These chromophore maps are two-dimensional quantitative representations of the involved skin areas that demonstrated characteristics of the recovery process of the patient after the procedure. We conclude that multispectral imaging can be a valuable noninvasive tool in the study of edema and ecchymosis and can be used to document these chromophores in vivo and determine the efficacy of treatments in a clinical setting. © 2010 Copyright SPIE - The International Society for Optical Engineering. Source


Seo I.,Johnson and Johnson CPPW | Chu M.,Johnson and Johnson CPPW | Bargo P.R.,Johnson and Johnson CPPW | Kollias N.,Johnson and Johnson CPPW
Photochemistry and Photobiology | Year: 2014

Erythema and pigment responses of human skin following an acute exposure to ultraviolet radiation (UVR) are frequently used to determine the photosensitivity of the skin. In this study we investigated the responses of the skin to a microscale area of UVR exposure (MiR) and compared the responses to a macro-scale area of exposure (MaR). Ten human volunteers were tested with solar-simulated radiation on their upper arm or back using a beam size of 8 mm and 0.2 mm in diameter. The fluence required to produce a minimally perceptible erythema (MED) using the MiR was found to be higher than that for the MaR. The erythema response extended beyond the exposed area and this became pronounced when the beam size was microscopic. Reflectance confocal microscopy in vivo revealed that MiR induced cellular alterations within a confined area of smaller dimensions than the area of exposure. Pigment responses were confined within the areas of cellular damage. The erythema expression of exposed skin recovered faster for the sites receiving MiR even when the applied fluence was higher than the MED for the MaR. Through the use of MiR we were able to visualize spatially dissimilar skin responses of erythema and pigmentation suggesting different cellular mechanisms. © 2014 The American Society of Photobiology. Source


Seo I.,Johnson and Johnson CPPW | Bargo P.R.,Johnson and Johnson CPPW | Chu M.,Johnson and Johnson CPPW | Ruvolo E.,Johnson and Johnson CPPW | Kollias N.,Johnson and Johnson CPPW
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2011

The minimal erythema dose induced by solar-simulated radiation is a useful measure of UV sensitivity of skin. Most skin phototests have been conducted by projecting a flat field of UV radiation onto the skin in an area greater than 15 cm x 15 cm with an increment of radiation doses. In this study, we investigated the responses of human skin to solar-simulated radiation of different field sizes. Twelve human subjects of skin phototype I-IV were exposed to solar-simulated radiation (SSR) on their upper inner arm or on their lower back with a series of doses in increments of 20% in order to determine the threshold dose to induce a minimal perceptible erythema response (MED). Each dose was delivered with a liquid light guide (8 mm diameter on the back or 6 mm on the upper inner arm) and with quartz optical fibers of 200 μm diameter. The resulting skin responses were evaluated visually and investigated with a reflectance confocal microscope and imaging. The erythema response to the microscopic challenge was always diffuse with no clear boundaries extending to several times the exposed site diameter at doses greater than 2 MED. The skin returned to normal appearance from the microscopic challenge after two weeks of exposure while change in appearance for the larger areas persisted for several weeks to months. This new modality of testing provides the possibility to study skin at the microscopic level with a rapid recovery following challenge. © 2011 Copyright SPIE - The International Society for Optical Engineering. Source

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