Varying ratios of wavelengths in dual wavelength LED photomodulation alters gene expression profiles in human skin fibroblasts.

BACKGROUND AND OBJECTIVE: LED photomodulation has been shown to profoundly influence cellular behavior. A variety of parameters with LED photomodulation can alter cellular response in vitro. The effects of one visible and one infrared wavelength were evaluated to determine the optimal ratio to produce a net increase in dermal collagen by altering the ratio of total energy output of each wavelength. The ratio between the two wavelengths (590 and 870 nm) was shifted in 25% increments. STUDY DESIGN/MATERIALS AND METHODS: Human skin fibroblasts in culture were exposed to a 590/870 nm LED array with total combined energy density fixed at 4.0 mW/cm.. The ratio of 590/870 nm tested parameters were: 100/0%, 75/25%, 50/50%, 25/75%, and 0/100%. These ratios were delivered using pulsed duty cycle of exposure (250 milliseconds "on" time/100 milliseconds "off" time/100 pulses) for a total energy fluence of 0.1 J/cm.. Gene expression was examined using commercially available extra cellular matrix and adhesion molecule RT PCR Arrays (SA Biosciences, Frederick, MD) at 24 hours post-exposure. RESULTS: Different expression profiles were noticed for each of the ratios studied. Overall, there was an average (in an 80 gene array) of 6% expression difference in up or downregulation between the arrays. The greatest increase in collagen I and decrease in collagenase (MMP-1) was observed with 75/25% ratio of 590/870 nm. The addition of increasing proportions of IR wavelengths causes alteration in gene expression profile. The ratios of the wavelengths caused variation in magnitude of expression. CONCLUSIONS: Cell metabolism and gene expression can be altered by simultaneous exposure to multiple wavelengths of low energy light. Varying the ratios of specific wavelength intensity in both visible and near infrared light therapy can strongly influence resulting fibroblast gene expression patterns.

Theoretical z -pinch scaling relations for thermonuclear-fusion experiments.

We have developed wire-array z -pinch scaling relations for plasma-physics and inertial-confinement-fusion (ICF) experiments. The relations can be applied to the design of z -pinch accelerators for high-fusion-yield (approximately 0.4 GJ/shot) and inertial-fusion-energy (approximately 3 GJ/shot) research. We find that (delta(a)/delta(RT)) proportional (m/l)1/4 (Rgamma)(-1/2), where delta(a) is the imploding-sheath thickness of a wire-ablation-dominated pinch, delta(RT) is the sheath thickness of a Rayleigh-Taylor-dominated pinch, m is the total wire-array mass, l is the axial length of the array, R is the initial array radius, and gamma is a dimensionless functional of the shape of the current pulse that drives the pinch implosion. When the product Rgamma is held constant the sheath thickness is, at sufficiently large values of m/l, determined primarily by wire ablation. For an ablation-dominated pinch, we estimate that the peak radiated x-ray power P(r) proportional (I/tau(i))(3/2)Rlphigamma, where I is the peak pinch current, tau(i) is the pinch implosion time, and phi is a dimensionless functional of the current-pulse shape. This scaling relation is consistent with experiment when 13 MA < or = I < or = 20 MA, 93 ns < or = tau(i) < or = 169 ns, 10 mm < or = R < or = 20 mm, 10 mm < or = l < or = 20 mm, and 2.0 mg/cm < or = m/l < or = 7.3 mg/cm. Assuming an ablation-dominated pinch and that Rlphigamma is held constant, we find that the x-ray-power efficiency eta(x) congruent to P(r)/P(a) of a coupled pinch-accelerator system is proportional to (tau(i)P(r)(7/9 ))(-1), where P(a) is the peak accelerator power. The pinch current and accelerator power required to achieve a given value of P(r) are proportional to tau(i), and the requisite accelerator energy E(a) is proportional to tau2(i). These results suggest that the performance of an ablation-dominated pinch, and the efficiency of a coupled pinch-accelerator system, can be improved substantially by decreasing the implosion time tau(i). For an accelerator coupled to a double-pinch-driven hohlraum that drives the implosion of an ICF fuel capsule, we find that the accelerator power and energy required to achieve high-yield fusion scale as tau(i)0.36 and tau(i)1.36, respectively. Thus the accelerator requirements decrease as the implosion time is decreased. However, the x-ray-power and thermonuclear-yield efficiencies of such a coupled system increase with tau(i). We also find that increasing the anode-cathode gap of the pinch from 2 to 4 mm increases the requisite values of P(a) and E(a) by as much as a factor of 2.

Nanosecond electrical explosion of thin aluminum wires in a vacuum: experimental and computational investigations.

Experimental and computational investigations of nanosecond electrical explosion of a thin Al wire in vacuum are presented. We have demonstrated that increasing the current rate leads to increased energy deposited before voltage collapse. The experimental evidence for synchronization of the wire expansion and light emission with voltage collapse is presented. Hydrocarbons are indicated in optical spectra and their influence on breakdown physics is discussed. The radial velocity of low-density plasma reaches a value of approximately 100 km/s. The possibility of an over-critical phase transition due to high pressure is discussed. A one-dimensional magnetohydrodynamic (MHD) simulation shows good agreement with experimental data. The MHD simulation demonstrates separation of the exploding wire into a high-density cold core and a low-density hot corona as well as fast rejection of the current from the wire core to the corona during voltage collapse. Important features of the dynamics for the wire core and corona follow from the MHD simulation and are discussed.

Corona-free electrical explosion of polyimide-coated tungsten wire in vacuum.

We present experimental evidence of corona-free electrical explosion of dielectric-coated W wire in vacuum. A fast current rise of approximately 150 A/ns and a coating of 2 microm polyimide are both needed to achieve the corona-free regime of explosion. Breakdown is absent in corona-free explosion; the wire remains resistive, and this allows anomalously high energy deposition (approximately 20 times atomization enthalpy). MHD simulations reproduce the main differences between corona and corona-free explosions. A corona-free explosion of a wire can be useful for the generation of a hot plasma column by direct energy deposition.

Clinical efficacy assessment in photodamaged skin of 0.5% and 1.0% idebenone.

Idebenone is an antioxidant lower molecular weight analogue of coenzyme Q10. Previously, idebenone was shown to be a very effective antioxidant in its ability to protect against cell damage from oxidative stress in a variety of biochemical, cell biological, and in vivo methods, including its ability to suppress sunburn cell (SBC) formation in living skin. However, no clinical studies have been previously conducted to establish the efficacy of idebenone in a topical skincare formulation for the treatment of photodamaged skin. In this nonvehicle control study, 0.5% and 1.0% idebenone commercial formulations were evaluated in a clinical trial for topical safety and efficacy in photodamaged skin. Forty-one female subjects, aged 30-65, with moderate photodamaged skin were randomized to use a blind labelled (either 0.5% or 1.0% idebenone in otherwise identical lotion bases) skincare preparation twice daily for six weeks. Blinded expert grader assessments for skin roughness/dryness, fine lines/wrinkles, and global improvement in photodamage were performed at baseline, three weeks and six weeks. Electrical conductance readings for skin surface hydration and 35 mm digital photography were made at baseline after six weeks. Punch biopsies were taken from randomly selected subjects, baseline and after six weeks, and stained for certain antibodies (interleukin IL-6, interleukin IL-1b, matrixmetalloproteinase MMP-1, collagen I) using immunofluorescence microscopy. After six weeks' use of the 1.0% idebenone formula, a 26% reduction in skin roughness/dryness was observed, a 37% increase in skin hydration, a 29% reduction in fine lines/wrinkles, and a 33% improvement in overall global assessment of photodamaged skin. For the 0.5% idebenone formulation, a 23% reduction in skin roughness/dryness was observed, a 37% increase in skin hydration, a 27% reduction in fine lines/wrinkles, and a 30% improvement in overall global assessment of photodamaged skin. The immunofluorescence staining revealed a decrease in IL-1b, IL-6, and MMP-1 and an increase in collagen I for both concentrations.

Idebenone: a new antioxidant - Part I. Relative assessment of oxidative stress protection capacity compared to commonly known antioxidants.

Topical applications of skin care products containing antioxidants have become increasingly popular. Numerous studies have elucidated the biological effects of these substances. General antiaging effects, anti-inflammatory properties, photoprotective properties, and prevention of ultraviolet (UV) immunosuppression have been documented. However, a standardized method to characterize and compare the properties and oxidative stress protection capacity of antioxidants was lacking. A multistep in vitro process utilizing a variety of biochemical and cell biological methods combined with in vivo studies was designed to compare the oxidative stress protective capacity of commonly used antioxidants. Data were presented for L-ascorbic acid, dl-alpha-tocopherol, kinetin, dl-alpha lipoic acid, ubiquinone, and idebenone. Methods included using UV-induced radical trapping/scavenging capacity measured by photochemiluminescence, pro-oxidative systems (LDL-CuSO(4), microsome-NADPH/ADP/Fe(3+)) with measurement of primary and secondary oxidation products, UVB irradiation of human keratinocytes, and in vivo evaluation, using the human sunburn cell (SBC) assay. Correlation and trends between in vitro and in vivo results were established, and the standardized test protocol was used to quantify oxidative stress protection capacity of antioxidants. Summarizing and totaling the data equally weighted for each oxidative stress study, the overall oxidative protection capacity scores of 95, 80, 68, 55, 52, and 41 were obtained for idebenone, dl-alpha tocopherol, kinetin, ubiquinone, L-ascorbic acid, and dl-alpha lipoic acid, respectively. The higher the score, the more effective the overall oxidative stress protection capacity of the antioxidant became. This multistep protocol may serve as a standard in investigating and comparing new putative antioxidants for topical use as well as a valuable tool to assess the anti-inflammatory properties, photoprotective properties, and prevention of UV immunosuppression of topical antioxidants.

X-ray emission from z pinches at 10 7 A: current scaling, gap closure, and shot-to-shot fluctuations.

We have measured the x-ray power and energy radiated by a tungsten-wire-array z pinch as a function of the peak pinch current and the width of the anode-cathode gap at the base of the pinch. The measurements were performed at 13- and 19-MA currents and 1-, 2-, 3-, and 4-mm gaps. The wire material, number of wires, wire-array diameter, wire-array length, wire-array-electrode design, normalized-pinch-current time history, implosion time, and diagnostic package were held constant for the experiments. To keep the implosion time constant, the mass of the array was increased as I2 (i.e., the diameter of each wire was increased as I), where I is the peak pinch current. At 19 MA, the mass of the 300-wire 20-mm-diam 10-mm-length array was 5.9 mg. For the configuration studied, we find that to eliminate the effects of gap closure on the radiated energy, the width of the gap must be increased approximately as I. For shots unaffected by gap closure, we find that the peak radiated x-ray power P(r) proportional to I1.24+/-0.18, the total radiated x-ray energy E(r) proportional to I1.73+/-0.18, the x-ray-power rise time tau(r) proportional to I0.39+/-0.34, and the x-ray-power pulse width tau(w) proportional to demonstrate that the internal energy and radiative opacity of the pinch are not responsible for the observed subquadratic power scaling. Heuristic wire-ablation arguments suggest that quadratic power scaling will be achieved if the implosion time tau(i) is scaled as I(-1/3). The measured 1sigma shot-to-shot fluctuations in P(r), E(r), tau(r), tau(w), and tau(i) are approximately 12%, 9%, 26%, 9%, and 2%, respectively, assuming that the fluctuations are independent of I. These variations are for one-half of the pinch. If the half observed radiates in a manner that is statistically independent of the other half, the variations are a factor of 2(1/2) less for the entire pinch. We calculate the effect that shot-to-shot fluctuations of a single pinch would have on the shot-success probability of the double-pinch inertial-confinement-fusion driver proposed by Hammer et al. [Phys. Plasmas 6, 2129 (1999)]. We find that on a given shot, the probability that two independent pinches would radiate the same peak power to within a factor of 1+/-alpha (where 0< or =alpha<<1) is equal to erf(alpha/2sigma), where sigma is the 1sigma fractional variation of the peak power radiated by a single pinch. Assuming alpha must be < or =7% to achieve adequate odd-Legendre-mode radiation symmetry for thermonuclear-fusion experiments, sigma must be <3% for the shot-success probability to be > or =90%. The observed (12/2(1/2))%=8.5% fluctuation in P(r) would provide adequate symmetry on 44% of the shots. We propose that three-dimensional radiative-magnetohydrodynamic simulations be performed to quantify the sensitivity of the x-ray emission to various initial conditions, and to determine whether an imploding z pinch is a spatiotemporal chaotic system.

Polarity effect for exploding wires in a vacuum.

Experimental evidence for a strong influence of the radial electric field on energy deposition into thin metal wires during their electrical explosion in vacuum is presented. Explosion of the metal wire with a positive polarity when the radial electric field "pushes" electrons into the wire results in twice as much deposited energy than with the negative polarity when the radial field "expels" electrons from the wires. Moreover, the axial structure of the deposited energy changes. This effect can be explained by the influence of radial electric field on electronic emission and on vapor breakdown along the wire surface.

Variable pulse erbium:YAG laser skin resurfacing of perioral rhytides and side-by-side comparison with carbon dioxide laser.

BACKGROUND AND OBJECTIVE: Laser resurfacing of facial rhytides has become a popular treatment option for many patients with wrinkles, photoaging, and acne scarring. Laser wavelength/pulse duration options and new techniques continue to shorten the healing phase associated with laser skin resurfacing while maintaining clinical efficacy. Variable pulse erbium:YAG (Er:YAG) laser systems are now available that offer the surgeon the ability to vary the Er:YAG pulse duration from a pulse that is primarily ablative to one that is more thermal. The objective of this study was to evaluate the histologic effects created with a variable pulse Er:YAG laser. To study prospectively the clinical effects on upper lip rhytides with a variable pulse Er:YAG laser when compared side by side with pulsed carbon dioxide (CO(2)) laser resurfacing. STUDY DESIGN/MATERIALS AND METHODS: Forty-two treatment sites on 21 patients were randomized and evaluated after treatment of the upper lip region with CO(2) laser resurfacing on one side and a variable pulse Er:YAG laser on the other. Patient diaries were maintained to assess erythema, crusting, pain, and pigmentary changes. Blinded objective grading of improvement was performed. Chromometer measurements were obtained to analyze erythema. RESULTS: The variable pulse Er:YAG laser treatment reduced the duration of crusting on average from 7.7 days with CO(2) to 3.4 days. Chromometer measurements noted decreased postoperative erythema. Grading by physicians in a blinded manner showed 63% improvement for the CO(2) treatment site and 48% improvement in the variable pulse Er:YAG site. No cases of permanent hyperpigmentation, hypopigmentation, or scarring occurred. CONCLUSION: The variable pulse Er:YAG laser resurfacing is a safe and effective resurfacing tool, which combines ablative and thermal modalities. The protocol used in this study approaches but does not equal the results we have traditionally seen with CO(2) laser resurfacing.

Laser hair removal: a review and report on the use of the long-pulsed alexandrite laser for hair reduction of the upper lip, leg, back, and bikini region.

BACKGROUND: The mechanism and permanence of laser-assisted hair removal remains a formidable task in the medical community. OBJECTIVE: The purpose of this study was to determine the safety and long-term efficacy of the long-pulsed or normal mode alexandrite infrared laser for hair depilation. METHODS: Beginning in October 1996, a total of 31 anatomic sites on 22 patients ranging in age from 25 to 59 years (mean 42 years) were evaluated to assess hair removal. Treatment sites included 17 upper lips, 9 legs, 2 backs, and 3 bikini regions. Eligible patients were of Fitzpatrick skin types I-III. Patients were treated using the long-pulsed alexandrite infrared laser at 755 nm, single-pulse technique, 10 mm spot size, 10% overlap, pulse durations of 5, 10, and 20 msec, and a fluence of 20 J/cm2. Subjective patient improvement and objective, blinded graded improvement was assessed at 1, 2, 3, and 6 months. RESULTS: Objective blinded grading at 6 months revealed that hair reduction varied both with the pulse duration and anatomic location. Maximum reductions observed were 40%, 56%, 50%, and 15% for the lip, leg, back, and bikini areas, respectively. Upper lip hair reduction increased from 40% to 54% at 6 months when a second treatment was performed 8 weeks after the initial treatment. CONCLUSION: The long-pulsed alexandrite laser is safe and effective in reducing hair growth. Treatment efficacy varies with the anatomic location, pulse duration, and number of treatments. A single-pulse technique utilizing a 10 msec pulse duration at 20 J/cm2 produced the greatest hair reduction. No permanent adverse effects occurred on skin types I-III at the parameters tested.

Combined CO2/erbium:YAG laser resurfacing of peri-oral rhytides and side-by-side comparison with carbon dioxide laser alone.

BACKGROUND: Laser resurfacing of facial rhytids has become a popular treatment option for many patients with wrinkles, photoaging, and acne scarring. Laser wavelength options and optimization of techniques continue to evolve in an attempt to shorten the healing phase associated with laser skin resurfacing. OBJECTIVE: To prospectively study the clinical effects of pulsed carbon dioxide (CO2) laser resurfacing of facial rhytids used alone, compared with a combination of CO2 and the pulsed Erbium:YAG (Er:YAG) laser. METHODS: Forty treatment sites on 20 patients were randomized and evaluated following treatment of the upper lip region with a combination of CO2 laser resurfacing alone or with the same CO2 laser treatment followed by 3 passes with the Er:YAG laser. Patient diaries were maintained to assess erythema, crusting, pain, itching, swelling, pigmentary changes, and the day of first make-up application. Blinded objective grading of improvement was independently assessed by 4 blinded observers at time intervals 3, 6, and 10 days, and 1, 2, and 4 months. Chromometer measurements of erythema were also analyzed and percentage moisture recorded. RESULTS: Subjectively, all patients reported, on average, 10 days of redness and 2.4 days of pain, with no significant difference noted between the two procedures. On average, patients were able to apply make-up 5.5 days postoperatively, regardless of which procedure used. However, the combined CO2/Er:YAG laser treatment patients experienced reduced duration of crusting, compared to the patients treated with CO2 alone. The duration of crusting was reduced on average from 7.4 to 6.5 days, and also the duration of itching was reduced in patients receiving combined treatment from 5.5 to 4.8 days. Chromometer measurements noted no significant difference between techniques in the rate of resolution of erythema. Blinded objective grading revealed that crusting was reduced on average from 7.2 to 6.0 days, and swelling was reduced from 6.3 to 6.0 days in patients receiving the combined procedure. No cases of permanent hyperpigmentation, hypopigmentation, or scarring occurred in any patients. CONCLUSION: The addition of the Er:YAG laser following CO2 laser resurfacing reduces the duration of crusting, swelling, and itching postoperatively. Medium to deep (Grade III) facial rhytids were improved by 70% with both procedures with no significant difference noted between techniques.

Hair removal using a long-pulsed alexandrite laser.

The use of lasers for hair depilation has become a common modality for physicians in the recent past. As new lasers are developed, the complex mechanisms affecting this form of treatment are now under close investigation. The long-pulsed alexandrite laser functioning at a wavelength of 755 nm has recently been added to the armamentarium of health care providers to assist patients with unwanted body hair. A review of the embryology and anatomy of the hair follicle are discussed, as well as the findings of recent studies using this form of laser therapy. Using the suggested treatment protocols offered laser assisted depilation may be effectively achieved. The degree and duration of reduction vary with anatomic site and improve with multiple treatments.

Laser therapy of spider leg veins: clinical evaluation of a new long pulsed alexandrite laser.

BACKGROUND: The response of spider leg veins to laser or intense pulsed light therapy has generally been characterized by varying degrees of success and frequently inconsistent clinical response rates. OBJECTIVE: The purpose of this study was to examine the effectiveness of the 755 nm long pulsed infrared alexandrite (LPA) laser for the treatment of leg telangiectasias. METHODS: This study was constructed in four phases. Phase I examined 28 patients with variable sized telangiectasias using 5 treatment parameters (15 J/cm2 x 1 pulse, 20 J/cm2 x 1 pulse, 20 J/cm2 x 2 pulses, 20 J/cm2 x 3 pulses, or 30 J/cm2 x 1 pulse). Each patient received 3 treatments at 4 week intervals with the LPA. Patient diaries were obtained to examine the effects of the treatments. Subjective grading was performed at each follow-up visit by the investigators. Blinded objective grading was performed at the conclusion of the study by trained observers. Phase II examined the effects of these treatment parameters on varying vessel diameters. Vessels were grouped into small (<0.4 mm), intermediate (0.4-1.0 mm), and large (1.0-3.0 mm) subsets. Phase III examined the effects of a combination of LPA treatment followed by 23.4% hypertonic saline sclerotherapy. Subjective and blinded objective grading was used to determine improvement after a single treatment with the LPA at 20 J/cm2, single pulsed with a pulse duration of 5 or 10 msec followed by treatment with 23.4% hypertonic saline injected 3, 7, 14, or 28 days after laser therapy. Phase IV involved biopsies after LPA treatment alone at time intervals of immediately posttreatment and 5 and 21 days posttreatment. RESULTS: These evaluations revealed that the optimal treatment parameters for LPA therapy alone appeared to be 20 J/cm2, double pulsed at a repetition rate of one Hz. After 3 treatments at 4 week intervals, subjective grading indicated a 63% reduction in leg telangiectasias. Medium diameter vessels responded best with small vessel diameters responding poorly, if at all. The addition of 23.4% hypertonic saline sclerotherapy performed 3 to 7 days after laser therapy (LPA at 20 J/cm2, single pulsed with a pulse duration of 5 msec) produced 87% reduction in leg telangiectasias. Biopsies after LPA treatment revealed vessel wall endothelial cell necrosis at 5 days with fibrosis occurring at 3 weeks. The optimal clinical "window" for sclerotherapy seems to coincide with the period of endothelial cell necrosis. CONCLUSION: LPA therapy is most effective for leg telangiectasias 0.4-3.0 mm in diameter. This LPA technique is significantly improved with the addition of sclerotherapy.

Comparison of topical therapy for striae alba (20% glycolic acid/0.05% tretinoin versus 20% glycolic acid/10% L-ascorbic acid).

BACKGROUND: Topical treatment of striae rubra with 0.1% tretinoin and laser treatment of striae rubra and alba with the 585-nm pulsed dye laser are proven therapeutic options. However, little efficacy has been shown for treatment of striae alba topically, and the laser is currently not a suitable treatment option for darker ethnic skin types. OBJECTIVE: The purpose of this study was to demonstrate that selected commercial topical agents can improve the appearance of striae alba. METHODS: Ten patients of varying skin types (I-V) having straie distensae alba on the abdomen or thighs were selected to evaluate the effectiveness of two topical treatment regimens. Patients were placed on daily topical application of 20% glycolic acid (MD Forte) to the entire treatment area. In addition, the patients applied 10% L-ascorbic acid, 2% zinc sulfate, and 0.5% tyrosine to half to the treatment area and 0.05% tretinoin emollient cream (Renova) to the other half of the treatment area. The creams were applied on a daily basis for 12 weeks. Improvement was evaluated at 4 and 12 weeks in an objective unblinded fashion at the follow-up visits, a objective blinded fashion by visual grading at the conclusion of the study, and in an objective blinded fashion with profilometry. Additionally, histopathologic analysis was performed. RESULTS: Analysis of these data reveals: 1) both regimens can improve the appearance of stretch marks; 2) these topical therapy regimens are safe and effective in study patients with minimal irritation; 3) elastin content within the reticular and papillary dermis can increase with topical 20% glycolic acid combined with 0.05% tretinoin emollient cream therapy; 4) both regimens increased epidermal thickness and decreased papillary dermal thickness in treated stretch marks when compared with untreated stretch marks; 5) combined epidermal and papillary dermal thickness in stretch marks treated with either topical regimen approaches that of normal skin; and 6) profilometry can objectively measure differences in skin texture associated with striae treatments when compared to controls, however, it is not sensitive enough to justify comparison or quantitative improvements between similarly effective treatments.

Accelerated laser resurfacing wound healing using a triad of topical antioxidants.

BACKGROUND: The speed of wound healing and the duration of erythema are the primary complaints after laser skin resurfacing. Antioxidants have been shown to enhance the healing of wounds by reducing free radical damage. Reepithelialization is also enhanced by the moist environment produced by occlusive dressings. OBJECTIVE: This study was conducted to compare two occlusive agents: white petrolatum and "melting" petrolatum. Another arm of the study evaluated the use of melting petrolatum with and without a triad of topical antioxidants (TTA). RESULTS: Plain white petrolatum proved superior to melting petrolatum in time required for reepithelialization as well as in discomfort. Crusting and pain were decreased with white petrolatum but duration of erythema was equivalent. Wound healing was enhanced when TTA was added. Time for reepithelialization, duration of crusting and scabbing, pain, redness, and swelling were decreased when TTA was added to topical therapy. CONCLUSION: TTA compound enhances and hastens wound healing. White petrolatum as a base occlusive vehicle shortens reepithelialization compared with "melting" petrolatum.

Body contouring: a preliminary report on the use of the silhouette device for treating cellulite.

Cellulite is a common condition affecting 85% of postadolescent women. Recent advances in aesthetic techniques have initiated a new pursuit into understanding the cause and treatment of this condition. A recently introduced "roller massage therapy" device, Silhouette, was selected for evaluation in this study. Three patients were enrolled into this private practice, medical school-affiliated, prospective pilot project. The study objective was to identify whether the Silhouette device could generate reproducible reductions in the appearance of cellulite or alter body appearance, specifically in the abdominal, buttock, and thigh regions. A secondary goal was to evaluate the effectiveness of various measuring devices used to quantify cellulite regression. These included serial body weights, percent body fat, relative fat distribution, specific anatomic measurements, diagnostic ultrasound, and serial morphed photographic analysis and laboratory data. Initial results showed that 16 biweekly treatments produced minimal changes in body weight or percent body fat. On average, thigh circumferences increased by 1.7 mm and 8.7 mm in the right and left proximal thighs and decreased by 25 mm and 22 mm in the right and left distal thighs, respectively. Diagnostic ultrasound scans showed trends that may provide further insight into a possible mechanism of action. Relative fat distribution values taken from four selected sites proved the most significant finding with selected treatment sites improving on average from 0.8 to 2.1 units (mean 1.5 units/site). This technique provided safe yet modest improvement in the appearance of cellulite. The mechanism of this improvement remains unknown. Further research is needed to determine the mechanism of this improvement, its longevity, optimum treatment parameters, and whether maintenance therapy is needed.

The erbium: YAG laser: a review and preliminary report on resurfacing of the face, neck, and hands.

The use of short-pulsed or flash-scanned CO(2) lasers to resurface skin has rapidly joined chemical peels and dermabrasion as an accepted procedure. The purpose of this study was to evaluate a mid-infrared pulsed Erbium: YAG laser prospectively to determine its clinical efficacy for resurfacing of the face, neck, and hands. Postoperative changes and recovery period were also evaluated. A total of 21 patients were evaluated on a prospective basis with Er: YAG laser resurfacing (12 crow's feet, five upper lips, three hands, and one neck). Additional nonstudy clinical experience is also reported. Posttreatment crusting or scabbing lasted an average of 2.7 days, pain an average of 3 days, erythema an average of 5.2 days, and swelling an average of 3 days. Blinded subjective grading was performed 2 months postoperatively. This grading revealed a 52% combined improvement from all areas. The appearance of crow's feet was improved by 58%; upper lip, 43%; dorsal hand, 48%; and neck, 44%. Overall the Er: YAG laser consistently produced reduction in rhytids and improvement in the appearance of sun-damaged skin. The times for reepithelialization and duration of erythema were strikingly shorter than those typically observed with current CO(2) laser resurfacing. This report details the study, reviews Er: YAG laser technology, and compares our findings with those observed with standard CO(2) laser resurfacing.

Treatment of stretch marks with the 585-nm flashlamp-pumped pulsed dye laser.

BACKGROUND: Striae, or stretch marks, are very common skin disorders that do not impair bodily function, but are of considerable cosmetic concern to many patients. Traditionally, treatment options have been very limited. This study examines the results of treating striae using the 585-nm pulsed dye laser. Stimulation of a variety of wound healing processes has been attributed to low energy laser therapy. Clinically, improvement of hypertrophic and erythematous scars with the 585-nm pulsed dye laser at energy densities of 6-7 J/cm2 is well established. Since striae are dermal scars, evaluation of this same therapy to treat striae was undertaken. OBJECTIVE: To evaluate the effectiveness of the 585-nm flashlamp-pumped pulse dye laser in treating cutaneous striae. METHODS: Thirty-nine striae were treated with four treatment protocols. These treated striae were compared with untreated striae controls in the same patient. The patients ages ranged from 23 to 52 years, with an average age of 36 years. The average age of the treated striae prior to initial treatment was 14 years (range, 8 months to 32 years). Treatment parameters included spot sizes of 7 and 10 mm and fluences of 2.0, 2.5, 3.0, and 4.0 J/cm2. Response to therapy was evaluated through clinical grading, sequential photography, and optical profilometry at a blinded laboratory. Skin biopsies were also examined with light microscopy from two of the 39 striae that were treated. RESULTS: Subjectively, striae appeared to return toward the appearance of normal skin with all protocols. However, the protocol with 10-mm spot size using 3.0 J/cm2 fluence improved the appearance of striae better than the other treatment protocols. Objectively, shadow profilometry revealed that all treatment protocols reduced skin shadowing in striae. This result corresponds with surface patterns of striae returning to that closely resembling adjacent normal skin surface patterns. Histologically, using hematoxylin and eosin stains as well as elastin strains, striae treated with a low fluence pulsed dye laser treatment protocol regained normal appearing elastin content when compared with normal (non-striae) skin adjacent to the treated striae. CONCLUSION: Treatment with the 585-nm pulsed dye laser at low energy densities was shown to improve the appearance of striae. Apparent increased dermal elastin was also observed 8 weeks posttherapy and possibly contributed to the improvement seen in the study patients.

Pulsed dye laser treatment of warts.

OBJECTIVE: To determine the safety and efficacy of the flashlamp-pumped pulsed dye laser for the treatment of uncomplicated and recalcitrant warts. DESIGN: Observational study. PATIENTS: A total of 142 patients with 703 recalcitrant and 25 previously untreated warts consecutively referred to two tertiary care laser centers from July 1993 through January 1994. INTERVENTION: Photocoagulation with the flashlamp-pumped pulsed dye laser. MAIN OUTCOME MEASURES: Complete resolution of treated warts after a follow-up ranging from 3 to 9 months. RESULTS: The overall response rates were 99% for body, limb, and anogenital warts; 95% for hand warts; 84% for plantar warts; and 83% for periungual warts. Side effects were limited and infrequent. CONCLUSION: Pulsed dye laser therapy is a highly effective and safe method used to selectively destroy warts without damaging the surrounding skin.