Better understanding of digital photography for skin color measurement: With a special emphasis on light characteristics

Background/Aim: Digital photography can be used to measure skin color colorimetrically when combined with proper techniques. To better understand the settings of digital photography for the evaluation and measurement of skin colors, we used a tungsten lamp with filters and the custom white balance (WB) function of a digital camera. Materials and methods: All colored squares on a color chart were photographed with each original and filtered light, analyzed into CIELAB coordinates to produce the calibration method for each given light setting, and compared statistically with reference coordinates obtained using a reflectance spectrophotometer. They were summarized as to the typical color groups, such as skin colors. We compared these results according to the fixed vs. custom WB of a digital camera. Results: The accuracy of color measurement was improved when using light with a proper color temperature conversion filter. The skin colors from color charts could be measured more accurately using a fixed WB. In vivo measurement of skin color was easy and possible with our method and settings. Conclusion: The color temperature conversion filter that produced daylight‐like light from the tungsten lamp was the best choice when combined with fixed WB for the measurement of colors and acceptable photographs.     

Ability to estimate relative percutaneous penetration via a surrogate maker – trans epidermal water loss?

Aims: This study measures the dynamic change of the trans‐epidermal water loss (TEWL) rate and in vitro skin permeation data of tritiated water and [¹⁴C]‐clonidine HCl in order to refine our knowledge in the relationship between percutaneous penetration and TEWL. Measures: TEWL values were measured before and during the experimental period. Single application of tritiated water and [¹⁴C]‐clonidine HCl were dosed at the same time on dermatomed human skin samples collected from 12 donors in a flow through diffusion cell system. Radioactivity of absorbed dose: stratum corneum, epidermis, dermis, receptor fluid collected every 4 hours, as well as removable dose residue was counted to determine accountability, percent dose, μg equivalent, and flux rate. These data were further combined with TEWL values to analyze their possible relationship. Results: Results showed that baseline TEWL values correlated with the thickness of dermatomed skin (r=?0.44, P=0.007), and with tritiated water fluxes (r=0.34, P=0.04) and [¹⁴C]‐clonidine HCl (r=0.36; P=0.03). The fluxes of tritiated water and [¹⁴C]‐clonidine HCl were correlated (r=0.67, P<0.001). When TEWL and permeation data were compared, the pattern of tritiated water expressed as a percent dose permeated in receptor fluid resembled the TEWL pattern. Conclusion: The methodology described provides evidences of the correlation of TEWL and skin integrity and skin permeation and further demonstrates to be a rapid alternative to tritiated water permeation for measuring skin barrier functions in vitro. To develop TEWL measurement as a possible predictive model to assess in vitro percutaneous absorption, however more chemicals with various physical‐chemical properties need to be examined, and the relationships to TEWL and tritiated water flux better defined.     

Skin subtype categorization based on a new questionnaire for Korean women

Background: Several terms have been used to characterize skin types. However, these are not based on evident dermatologic definitions, which usually include subjective and psychological properties. Objective: The objective of this study is to establish a new practical questionnaire to classify skin subtypes in Korean women to establish treatment and skin care guidance. Methods: Eight experts developed consensus statements about skin types and created a questionnaire. The content was categorized into four major subtypes: dry or non-dry; oily or nonoily; sensitive or nonsensitive; and pigmented or nonpigmented. A total of 512 patients completed the questionnaire. Correlations with age, skin Fitzpatrick’s phototypes, and dermatologic comorbidities were analyzed. Results: Korean women commonly have oily skin but complain of dryness after cleansing. They are especially sensitive to skin care products and prone to developing pigmentary lesions. There was a trend in the proportion of dry skin subtype that increased as pigmented skin increased and oily skin decreased with advanced age. The proportion of sensitive skin was higher in patients with dermatologic comorbidities. The proportion of the pigmented skin was higher in darker Fitzpatrick skin phototypes. Conclusion: This is the first questionnaire established for Korean women to classify practical skin subtypes and may provide a basis for treating various skin conditions.     

Protoporphyrin IX formation and photobleaching in different layers of normal human skin: Methyl‐ and hexylaminolevulinate and different light sources

Topical photodynamic therapy (PDT) is used for various skin disorders, and selective targeting of specific skin structures is desirable. The objective was to assess accumulation of PpIX fluorescence and photobleaching within skin layers using different photosensitizers and light sources. Normal human skin was tape‐stripped and incubated with 20% methylaminolevulinate (MAL) or 20% hexylaminolevulinate (HAL) for 3 h. Fluorescence microscopy quantified PpIX accumulation in epidermis, superficial, mid and deep dermis, down to 2 mm. PpIX photobleaching by light‐emitting diode (LED, 632 nm, 18 and 37 J/cm²), intense pulsed light (IPL, 500–650 nm, 36 and 72 J/cm²) and long‐pulsed dye laser (LPDL, 595 nm, 7.5 and 15 J/cm²) was measured using fluorescence photography and microscopy. We found higher PpIX fluorescence intensities in epidermis and superficial dermis in HAL‐incubated skin than MAL‐incubated skin (P < 0.001). In mid and deep dermis, fluorescence intensities were higher (37%) in HAL‐treated skin than MAL‐treated skin, although not significant (P = ns). At skin surface, photobleaching was significantly higher (90–98%) after LED illumination (18 and 37 J/cm²) than IPL (29–53%, 36 and 72 J/cm²) and LPDL (43–62%, 7 and 15 J/cm²) (P < 0.001). Within the skin, photobleaching was steady from epidermis to deep dermis by LED illumination (37 J/cm², P = ns), but declined from epidermis to mid and deep dermis for IPL‐treated skin and LPDL‐treated skin (IPL 72 J/cm²: 26–15%; LPDL 15 J/cm²: 37–23%) (P < 0.04). Clinically, erythema correlated linearly with MAL and HAL‐induced photobleaching (r² = 0.175, P < 0.001). In conclusion, selective PpIX accumulation indicates HAL as an alternative to MAL for epidermal‐targeted PDT. In clinically relevant doses, PpIX photobleaching throughout the skin was more profound following LED than LPDL and IPL exposure.     

Polarized light photography enhances visualization of inflammatory lesions of acne vulgaris

Background: Polarized light photography has been used to selectively differentiate surface from subsurface features of photoaged skin.Objective: Our purpose was to compare acne assessments obtained from clinical evaluations with assessments from photographs obtained with flash photography and with perpendicular polarized light photography.Methods: Assessments of acne with the Cunliffe scale were made of 32 subjects. Retrospective evaluations of standard and perpendicular polarized light photographs were made in a blinded fashion by a panel of evaluators.Results: Visualization of inflammatory acne lesions was enhanced with perpendicular polarized light photography, with clear delineation of erythematous borders. Acne assessments with the use of a Cunliffe scale were significantly higher (p = 0.001) from perpendicular polarized light photographs than for clinical evaluations.Conclusion: Polarized light photography enhances visualization of inflammatory acne lesions in a manner not possible with conventional flash photographs, permitting accurate evaluation of the extent of disease and the effectiveness of therapy. (J Am Acad Dermatol 1997;37:948-52.)     

SENILE DRY SKIN TYPE SJÖGREN'S SYNDROME

Background. Elderly patients may show asteatotic dermatitis complicating Sjögren's syndrome (sjs) that we have named “senile dry skin type sjs.” To define the condition further, we have examined a group of patients with sjs and have recorded clinical and laboratory findings in these patients. Patients and Materials. Of the 36 patients, 11 were men and 25 were women, with a mean age of 72 years. In addition to the subjective sensation of dryness of the eyes and oral cavity and objective signs of dryness revealed by the Schirmer test, the rose bengal test, minor labial gland biopsy, and sialography were carried out, as well as other hematologic and immunologic tests. Results. The following abnormal laboratory tests were found: elevated erythrocyte sedimentation rate (85%), mild hepatic dysfunction (50%), and anemia (45%), leukopenia (42%), and thrombocytopenia (16%). Immunologic abnormalities were also observed, such as: positive antinuclear antibody (55%), an increase in gamma globulin (28%), and a positive rheumatoid factor (20%). In 11 of the 36 patients (30%), the subjective sensation of dryness was absent and only objective signs of dryness were present. Conclusions. The present study suggests that dry–skin–dermatitis associated with sjs is rather common in the elderly.     

The effect of 308nm excimer laser on segmental vitiligo: a retrospective study of 80 patients with segmental vitiligo

Background: Segmental vitiligo (SV), which frequently accompanies poliosis, indicating a poor prognosis that is likely resistant to treatments. Objectives: In this study, we performed a retrospective analysis to evaluate the treatment response to 308 nm excimer laser in SV patients. Methods: A retrospective chart and photographic review was performed on 80 SV patients who had been treated with 308 nm excimer laser for >3 months. Results: Eighty patients with SV (mean age: 24.0 years ± 15.3, males: 50%) were included in this study. The mean grade of repigmentation was 2.3 after 20.6 months of mean treatment duration; 23.8% of 80 patients showed grade 4, 20% showed grade 3, and 56.2% showed grade 1–2 repigmentation. However, none of them achieved complete repigmentation with excimer laser. The degree of repigmentation was positively correlated with treatment duration (r=0.315, P=0.004) and cumulative ultraviolet (UV) dosage (r=0.366, P=0.001), whereas it was negatively correlated with disease duration (r=?0.265, P=0.017). Conclusion: This study suggests that SV has a better repigmentation response when excimer laser is used at earlier stages of the disease and long‐term use and high cumulative UV energy of the excimer laser elicit better responses. Additional treatments like surgical procedures in addition to excimer laser should be considered for complete repigmentation.     

Melanin and facial skin fluorescence as markers of yellowish discoloration with aging

Background: Although one clinical sign of aging and/or photoaging is a yellowish discoloration of the facial skin, little is known about the cause of this change. In addition to the increase in the epidermal melanin content, it has been suggested that advanced glycation end products (AGEs), which are known to accumulate in photoaged skin, may affect this discoloration. Aim: The objective of this pilot study was to non‐invasively investigate the roles of melanin and AGEs in this yellowish discoloration of the facial skin. Methods: We examined the spectral reflectance at the cheek in 40 healthy Japanese women of various ages (mean age, 38.1 years) using a reflectance spectrophotometer and a spectrofluorimeter. The degree of yellowish tint was evaluated in terms of b^*. The amount of melanin in the skin was evaluated by calculating the melanin index (MI) A₆₄₀–A₆₇₀ [A_λ: log₁₀ (1/reflectance) at a wavelength of λ]. The amount of AGEs was roughly evaluated using the AGEs index, which is thought to linearly correlate with the amount of intrinsic fluorescence markers irrespective of the concentration of melanin and is defined as follows: AGEs index=I₅/SQR (I₁×I₂). In this equation, the intensities of reflectance are I₁ at an excitation wavelength of 335 nm, I₂ at an emission wavelength of 390 nm and I₅ at 390 nm under an excitation wavelength of 335 nm. Results: Both b^* and the AGEs index were significantly correlated with subject age (r=0.34, P<0.05 and r=0.68, P<0.0001, respectively). Significant correlations were also observed between MI and b^* (r=0.63, P<0.0001) and between the AGEs index and b^* (r=0.53, P<0.0005). However, no significant correlations were seen between MI and the AGEs index. Conclusion: The AGEs index does not appear to be influenced by the amount of melanin and may be utilized as an indicator of the amount of AGEs in the skin. AGEs are likely to play a role in the yellowish discoloration of skin with aging.     

A study of a method for distribution analysis of skin color

Background/aims: The objective and quantitative assessment of the skin is important in medical and cosmeceutical research. Assessment of color is an important element for analyzing the surface of the skin, which is usually determined subjectively by a doctor or using color analysis devices. These devices, however, cannot provide correct color information because color is construed from the mean value of the observation region, and analysis of color distribution is impossible. The purpose of this paper is to develop an objective analysis method to permit skin color measurement of each pixel unit of an image and analyze the distribution of skin surface color. Methods: The Skin Color Distribution Analyzer (SCDA) is an analysis method newly developed at the Research Institute for Skin Image at Korea University. The SCDA system presented in this paper performed a novel form of quantitative and objective analysis of skin color distribution using each pixel color model parameter found in image wavelength information. In this paper, distribution analysis was conducted on normal skin and skin lesions and skin affected by artificially induced irritant contact dermatitis and pigmented nevous. The method selected a grade using a color model parameter. Twenty healthy Korean males participated in this study. A comparative study of the eight anatomical areas was performed, including the exposure and non‐exposure parts and the medial aspect and the lateral aspect of the forearm. A reliability test for the SCDA system was also conducted with a spectrometer (SPEC) using the color analysis method. Results: Each skin lesion was precisely segmented by grade and each parameter hada different statistical significance for results of analysis of distribution in pigmented nevous and the artificially induced irritant contact dermatitis. Parameters L^*, b^*, a^*, and EI showed salient traits. Showed resemble measured result in the SCDA system and the SPEC of normal skin. The exposed site, in comparison with the non‐exposed site, showed a notable difference in the L^* parameter and a significant statistical difference in the x and z parameters, except b^*. The comparison of the medial and lateral aspects of the forearm showed a notable difference in the L^* parameter and a significant statistical difference in the parameters except y and b^*. In the reliability test result using the SCDA system and the SPEC, the SCDA system was highly reliabile in terms of the CV value in all color model parameters. Conclusions: The color distribution analysis method using the SCDA system has revealed an aspect that the existent method of medical research has not shown, and is considered to be more reliable than other methods. This method can provide better study findings because it can be applied to other fields in addition to the medical science field and the ripple effect is thought to be bigger in other science field too.     

X-linked recessive ichthyosis: an impaired barrier function evokes limited gene responses before and after moisturizing treatments

Background X‐linked recessive ichthyosis (XLRI) is due to deletions or inactivating mutations in the steroid sulfatase (STS) gene. This results in an accumulation of cholesterol sulphate affecting the packing of intercorneocyte lipids. XLRI is characterized by dry, scaly skin and increased skin barrier permeability; patients are often dependent on daily use of moisturizers. Objectives To examine the biophysical and molecular changes in the skin of patients with XLRI compared with healthy volunteers, and to analyse the effects of moisturizers on the patients’ barrier function. Methods Patients with XLRI (n = 14) and healthy controls (n = 14) were included in the study. Skin dryness score, transepidermal water loss (TEWL) and skin surface pH were monitored at baseline, and punch biopsies were obtained for mRNA expression profiles determined by oligonucleotide arrays. Measurements were repeated in the patients with XLRI after a 4‐week treatment with three different moisturizers on the volar forearms. Results Patients with XLRI showed, compared with healthy controls, increased dryness and TEWL, equal skin pH and altered expression of 27 genes. There were no signs of activation of inflammation or repair pathways. Five selected genes were significantly altered also on quantitative polymerase chain reaction analysis. Treatment with the moisturizers showed similar effects: they improved skin dryness but had no effect on TEWL, pH or expression of selected genes. Conclusions Despite a dysfunctional skin barrier, the limited number of genes altered in XLRI skin suggests that no inflammatory or repair mechanisms are triggered. Treatment with moisturizers does not have any major impact on the skin barrier properties of patients with XLRI.     

Histological and immunofluorescence findings of non-follicular papulopustular lesions in patients with Behçet''s disease

Background Papulopustular lesions (PPL), the most common type of cutaneous lesions in Behçet's disease (BD), clinically may not be differentiated from ordinary acne. Disagreement exists as to the exact nature of these acneiform and folliculitis‐like lesions and whether to include them as a major criterion. Objective We investigated whether PPL can be a useful tool for the diagnosis of BD when non‐follicular lesions over the trunk or extremities were selected, and were correlated with histological and/or immunofluorescence study. Methods Seventeen patients with BD (five women, 12 men; mean ± SEM age, 32 ± 7.9 years), were enrolled in the study with blind histopathological and immunofluorescence studies. Biopsies of the PPL and adjacent (approximately 2 cm distant) normal‐appearing skin were performed from the extremities and trunk. Follicle‐based acneiform lesions and those lesions over face were excluded. Histological evaluation primarily included epidermal and dermal alterations, cellular infiltration and vascular changes. We also performed direct immunofluorescence studies, using polyclonal antibodies for IgA, IgG, IgM, C3 and fibrin. Results Lesional specimens of the patients with BD revealed a significant leucocytoclastic vasculitis as compared with non‐lesional skin (P < 0.05). The vessels of the lesional skin showed a higher IgM deposition than non‐lesional skin (52.9% and 17.6%) (P < 0.05). IgG, C3 and fibrin deposits on the vessels of the lesional skin were also higher than non‐lesional skin (35.3, 11.8%; 41.2, 17.6%; and 47.1, 17.6%, respectively), but the differences were not statistically significant. Conclusions Our findings indicate that non‐follicular PPL over the trunk or extremities are more specific, and immune complex‐mediated vasculitis is likely to be the main feature of these lesions, as they are in other cutaneous lesions of BD.     

A device for the color measurement and detection of spots on the skin

Background/purpose: In this work, we present a new and fast easy-to-use device that allows the measurement of color and the detection of spots on the human skin. The developed device is highly practical for relatively untrained operators and uses inexpensive consumer equipment, such as a CCD color camera, a light source composed of LEDs and a laptop. The knowledge of the color of the skin and the detection of spots can be useful in several areas such as in dermatology applications, the cosmetics industry, the biometrics field, health care, etc.
Methods: In order to perform these measurements the system takes a picture of the skin. After that, the operator selects the region of the skin to be analyzed on the displayed image and the system provides the CIELAB color coordinates, the chroma and the ITA parameter (Individual Tipology Angle), allowing the comparison with other reference images by means of CIELAB color differences. The system also detects spots, such as freckles, age spots, sunspots, pimples, black heads, etc., in a determined region, allowing the objective measurement of their size and area.
Results: The colorimetric information provided by a conventional spectrophotometer for the tested samples and the computed values obtained with the new developed system are quite similar, meaning that the developed system can be used to perform color measurements with relatively high accuracy. On the other hand, the feasibility of the system in order to detect and measure spots on the human skin has also been checked over a great amount of images, obtaining results with high precision.
Conclusion: In this work, we present a new system that may be very useful in order to measure the color and to detect spots of the skin. Its portability and easy applicability will be very useful in dermatologic and cosmetic studies.     

Objective and non‐invasive evaluation of photorejuvenation effect with intense pulsed light treatment in Asian skin

Background Intense pulsed light (IPL) has been widely used for photorejuvenation. Although previous literature has shown clinical effectiveness of IPL treatments on cutaneous photoaging, the associated changes in the biophysical properties of the skin following IPL treatments have not been fully elucidated. Objective The aim of this study was to evaluate changes in skin biophysical properties in patients with photoaging after IPL treatments, using non‐invasive, objective skin measuring devices. Patients and methods A total of 26 Korean women with facial dyschromias underwent three sessions of IPL treatment at 4‐week intervals. Outcome assessments included standardized photography, global evaluation by blinded investigators, patients’ self‐assessment and objective measurements of colour (Mexameter MX18, Chromatometer), elasticity (Cutometer), roughness (Visiometer), sebum (Sebumeter) and skin hydration (Corneometer). Results Intense pulsed light treatments produced a 15% decrease in the size of representative pigmented lesions (P < 0.05). Patients’ self‐assessment revealed that 84% and 58% of subjects considered their pigmented lesions and wrinkles were improved respectively. Objective colorimetric measurement demonstrated significant improvements following IPL treatments that were most remarkable after one session of IPL. Moreover, skin elasticity showed significant improvements at the end of the study. Skin wrinkles as measured using Visiometer showed a mild improvement without statistical significance. Sebum secretion and water content of skin remained unchanged. Conclusions Intense pulsed light provided significant improvement in the appearance of facial pigmented lesions in Korean patients. These effects appeared to be more remarkable in improving pigmentation, skin tone and elasticity.     

Elastotic degenerative change and yellowish discolouration in photoaged skin

Background/aims: One clinical sign of photodamage is a sallow discolouration of the skin, and solar elastotic degenerative change in the upper dermis may cause this change. We have attempted to quantify these phenomena and relate them to each other and to age. Methods: Twenty-seven healthy volunteers (age 18 to 61 years) were recruited. We examined the back of the hand of photodamaged individuals and the inner upper arm to demonstrate changes due to ageing. Each site was assessed for cutaneous blood flux using a laser Doppler fluxmeter (PF4000, Perimed UK), and for melanin pigmentation using a Melanin Index meter (Dermotronics Ltd, Cardiff, UK). Skin colour was measured using a diode array spectrophotometer (MCPD-1000, Photal, Japan), which computes CIE coordinates L*, a*, b*. Biopsies from each site were obtained from 13 of the subjects and were processed and stained with Gomori's aldehyde fuchsin. The percentage area of elastic staining material in the dermis was measured using image analysis. Sections were measured in four bands of 200 micron depth, and four fields were measured per band. Results: Neither melanin content nor skin blood flux correlated with age for either skin site. Percentage area of elastosis correlated with age on the exposed site from the uppermost 600 microns of the dermis, (<200 micron depth, r=0.74, P<0.01, 200<depth<400, r=0.57, P<0.05; 400<depth<600, r=0.57, P<0.05). No correlation was found on the unexposed inner upper arm site. On the back of hand site, a linear relationship was found between a parameter derived from the L*, a*, b* coordinates of (b*-5a*) and both age (r=0.904, P<0.001) and percentage area of elastosis of the uppermost 200 microns of dermis (r=0.74, P<0.01). This was not seen for the inner upper arm site. On exposed sites, the coefficient (b*-5a*) correlates with solar elastosis and these both correlate with age, which is related to exposure. Conclusion: This data confirms that solar elastosis accounts for the yellowish discolouration of sun damaged skin, and suggests that the coefficient b*-5a* could be used for the non-invasive quantification of solar elastosis.     

Digital image analysis for the evaluation of the inflammatory infiltrate in psoriasis

Traditionally the evaluation of the cellular infiltrate and protein expression in skin tissue sections is done by manual quantification. However, for reliable evaluation of histology in the development of new anti-psoriatic treatments there is a need for a more time-efficient and reproducible method. To test the use of digital image analysis (DIA) in this situation we compared the assessment of immunohistochemically stained skin sections with the more traditional manual quantification (MQ) and semi-quantitative analysis (SQA). The number of CD3⁺ T cells and the expression of E-selectin were evaluated in stained paired skin biopsies from 11 patients with chronic plaque psoriasis before and after initiation of anti-psoriasis therapy. We observed significant correlations between MQ and DIA for the number of T cells (epidermis: r=0.88, P≤0.01, dermis r=0.87, P≤0.01). Both DIA and MQ were equally effective in detecting reductions of T-cell numbers in active-treated patients. MQ took 20 h, compared to 6 h for DIA. We also observed significant correlations between SQA and DIA for the expression of E-selectin (r=0.88, P≤0.01), although DIA was more sensitive than SQA to detect (early) changes. SQA took 10 h, compared to 4 h for DIA. In conclusion, the quantification of the inflammatory infiltrate in psoriatic lesional skin by DIA generated similar results as MQ and SQA in a reliable, reproducible and higher time efficient fashion.     

Cold plasma is well‐tolerated and does not disturb skin barrier or reduce skin moisture

Background: Cold plasma, a new treatment principle in dermatology based on ionic discharge delivering reactive molecular species and UV‐light, exhibits strong antimicrobial efficacy in vitro and in vivo. Before implementing plasma as new medical treatment tool, its safety must be proven, as well as assessing skin tolerance and patient acceptance. Patients and Methods: We investigated the plasma effects of three different plasma sources (pulsed, non‐pulsed atmospheric pressure plasma jet (APPJ) and a dielectric barrier discharge (DBD)) on the transepidermal water loss (TEWL) and skin moisture after treating the fingertips of four healthy male volunteers. Results: TEWL values were reduced by pulsed APPJ and DBD by about 20% but increased after non‐pulsed APPJ by 5–20%. TEWL values normalized 30 min after all forms of plasma treatment. Skin moisture was increased immediately and 30 min after treatment with pulsed APPJ but was not affected by non‐pulsed APPJ and DBD. Conclusions: All plasma treatments were well‐tolerated and did not damage the skin barrier nor cause skin dryness. Cold plasma fulfils basic recommendations for safe use on human skin and as future option may serve as the first physical skin antiseptic.     

Epidermal thickness,skin pigmentation and constitutive photosensitivity

The important factors for UV sensitivity in humans are considered to be the skin pigmentation and the epidermal thickness. In this study on 73 Caucasians (age 20–85 years), we investigated in UV unexposed buttock skin the relationship between the UV sensitivity and constitutive skin pigmentation and thickness of the stratum corneum and the cellular part of the epidermis, in 34 normal people and in 39 skin cancer patients (20 patients with cutaneous malignant melanoma and 19 patients with basal cell carcinoma of the skin). Skin pigmentation was measured by skin reflectance spectroscopy, and UV sensitivity by phototest with a solar simulator. Thicknesses of the stratum corneum and the cellular part of the epidermis were determined by light microscopic evaluation of skin biopsies from the phototest areas. We found that epidermal thickness was independent of skin type and was not correlated to constitutive skin pigmentation. Thickness of the stratum corneum was statistically not different in normal persons and in skin cancer patients (P=0.4l) and was independent of gender (P=0.61) and age (P=0.56), while thickness of the cellular epidermis decreased with age (P<0.01). Stratum corneum thickness was found to be of minor importance for the constitutive UV sensitivity (accounting for on average 11% of the total photoprotection), which was mainly determined by the constitutive skin pigmentation (goodness-of-fit for correlation r=0.83). A theoretical model for the relationship of UV dose to induction of clinical erythema grade and skin pigmentation and thickness of the stratum corneum was developed. Objective measurements of skin pigmentation in UV unexposed skin by skin reflectance spectroscopy in Caucasians, normal people and people with cutaneous malignant melanoma and basal cell carcinoma of the skin predicts the constitutive UV sensitivity with a high degree of precision.     

An evaluation of topical 3% salicylic acid and 1% hydrocortisone in the maintenance of scalp pruritus

Background Scalp pruritus is a common condition causing dermatologic distress. The presence of skin scale on clothing is cosmetically undesirable and scalp scratching in public is socially embarrassing. Scratching can also result in removal of the cuticle and premature hair shaft fracture. Objective To demonstrate the efficacy of 3% salicylic acid in combination with 1% hydrocortisone in the treatment of scalp pruritus. Methods Sixty subjects with moderate scalp scaling and scalp pruritus were enrolled in a three‐arm double blind 2‐week study. The 20 subjects in arm 1 applied a topical 1% hydrocortisone product twice daily. The 20 subjects in arm 2 applied a topical 3% salicylic acid product twice daily. Lastly, the 20 subjects in arm 3 applied a topical 3% salicylic acid product in the morning and a topical 1% hydrocortisone product in the evening. Evaluations were performed at baseline, after 1 week of treatment, and after 2 weeks of treatment. The study investigator evaluated the subjects for scalp scale, erythema, excoriation, and overall assessment. In addition, scalp scale scrapings were collected and analyzed to gain further insight into scalp scale morphology. Subject assessments and scalp photography was also performed. Results The investigator assessments revealed less excoriation in the hydrocortisone twice daily arm over the salicylic acid twice daily arm (P = 0.03), which might be expected because of its anti‐inflammatory effect. The morning salicylic acid application and evening hydrocortisone application arm performed better than the salicylic acid twice daily group at week 2 in terms of erythema (P = 0.02), excoriation (P = 0.03), and overall assessment (P = 0.01). Scalp scale scrapings revealed the least amount of retained skin scale in the combination salicylic acid/hydrocortisone group. Conclusion The combination of a 3% salicylic acid keratolytic combined with a 1% hydrocortisone anti‐inflammatory provides the best relief of scalp pruritus.     

Anxiety and depression in patients with allergic and non-allergic cutaneous disorders

Background Numerous studies have shown that anxiety and depression are more prevalent among patients suffering from chronic skin disorders. Objectives The aims of this study were to assess the prevalences of depression and anxiety in patients suffering from chronic skin disorders, focusing particularly on allergic skin conditions. Additionally, we investigated resilience to disease progression using the Sense of Coherence Scale. Methods A total of 112 consecutive patients without known psychiatric disease were interviewed and asked to complete questionnaires in order to assess psychiatric symptomatology. The following scales were completed: the Mini International Neuropsychiatric Interview; the Hamilton Anxiety Scale (HAS); the Hamilton Depression Rating Scale (HDRS); and the self‐administered questionnaire for the Sense of Coherence Scale (SoCS). Results Rates of anxiety and depression in patients with allergic and non‐allergic conditions were considerably higher than those in the general population. This difference was notable in patients with allergic skin diseases, reaching 58.3 and 48.3%, compared with 15.4 and 23.1% for participants with non‐allergic conditions, as measured by the HAS and HDRS, respectively (P < 0.05). Statistically significant negative correlations between scores on the SoCS and scores on the HAS (r = ?0.45, P < 0.01) and HDRS (r = ?0.37, P < 0.01) were observed. Conclusions Our findings support the hypothesis that rates of anxiety and depression are higher among patients suffering from allergic chronic skin disorders. High SoCS scores may protect against the development of psychiatric illness in patients suffering from allergic skin disease.     

Photoelectric quantitative evaluation of argon laser treatment of port wine stains

Sixty patients with port wine stains were treated with the argon laser and graded visually into four subjective categories for changes in skin colour. For objective quantitative evaluation a photoelectric colorimeter was used. Reproducible definition of the lightness of the lesions into numbers was obtained. Differentials in lightness between normal contralateral skin and the portwine stain before and after treatment were quantified for each individual. The objective evaluation revealed a statistically significant difference between the four categories (P<0.05). The best clinical therapeutic effect was found to correlate with only 80–90% blanching. The average lightening obtained was 46.5%. Local heating of portwine stains in 12 patients showed no measurable darkening in the colour of the lesions, whereas the normal contralateral skin reacted with marked reddening. Determination of changes in lightness by photoelectric colorimetry provides an objective, quantitative means to evaluate the effects of laser treatment of port wine stains.