An assessment method for dermal structures using cross-polarized light imaging with a green light-emitting diode.

BACKGROUND: Several experimental methods for evaluating dermal structures exist; however, most of these are not used in dermatology clinics because of cost and functional limitations. OBJECTIVE: To propose a simple, non-invasive method for dermal structure evaluation using a green light-emitting diode (LED) with cross-polarized light (CPL) imaging and compare the quality of the images taken using either green or white LED. MATERIALS AND METHODS: Skin specimens were taken from fifteen cadavers. Images were captured using CPL photography with a green or white LED. The Commission International d'Eclairage L*a*b* (CIELAB) values were calculated for each image. The skin specimens were processed and stained with Masson's trichrome to visualize collagen fibers with major image scattering. The images were histologically analyzed, and correlational and regression analyses were performed to determine the relationship between the L* values and histologic measurements. RESULTS: The L* values for the green images were positively correlated with collagen fiber density, reticular collagen bundle diameter, and dermal thickness. They were effective for estimating dermal properties. The L* values for the white images were positively correlated with reticular collagen bundle diameter and dermal thickness. Correlational coefficients for white images were lower than those for green images. In regression analysis, green images showed a higher coefficient of determination (R2 ) for predicting reticular collagen bundle diameter than white images (0.1128 vs. 0.0827). CONCLUSION: Cross-polarized light imaging with a green LED is a simple, non-invasive method for evaluating dermal structures. The use of a green LED was also more effective for image analysis.

A simple morphometric analysis method for dermal microstructure using color thresholding and moments.

BACKGROUND: Proper assessment of dermal collagen fibers by dermatologists and researchers is essential. Histologic evaluation methods have limitations. We present a simple method for measurement of collagen fibers in human skin using Masson's trichrome staining. MATERIALS AND METHODS: Normal skin specimens from a cadaver were processed with Masson's trichrome, which can effectively stain collagen fibers blue with aniline dye. Optical photomicrographs of these slides were analyzed using ImageJ software. Color image processing, a histogram-based function of ImageJ for image segmentation, was performed with color moments thresholding technique. We selected blue areas by adjusting the blue channel to include specific values. The selected areas were highlighted and evaluated. We divided the image into layers of 0.09-mm2 areas from the top to bottom of the dermis. Each area was cropped and evaluated. RESULTS: Quantitative assessment yielded the quantitative size occupied by collagen fibers in an area of 0.09 mm2 . Calculation of the percentage in each area can be used to determine the density of collagen fibers. CONCLUSION: Measurements obtained with our method can be applied to research on dermal collagen fibers. We present a convenient quantitative assessment method for the dermal constituents in Masson's trichrome-stained slides.

Adult-onset lichen striatus versus adult blaschkitis: a clinicopathological review of 40 cases of acquired blaschkolinear inflammatory dermatosis.

BACKGROUND: Since the first description of adult blaschkitis (AB), the existence of this entity has been a matter of great debate. OBJECTIVES: To compare clinicopathological features of lichen striatus (LS) and AB cases. MATERIALS AND METHODS: We retrospectively reviewed the clinicopathological features of patients who clinically showed linear inflammatory dermatosis along Blaschko's lines based on a skin biopsy registry. RESULTS: Through a process of clinicopathological differential diagnosis, 27 cases of LS, three of AB, eight of linear lichen planus, and two of linear psoriasis were identified. Clinicopathological differences between LS and AB were mostly insignificant except for age at onset and multiple site involvement. In these cases, females were affected more frequently than males. The mean age at onset was 31.6 years, and the most common involved site was the leg. The lesions lasted approximately 8.3 months with few relapses. The most common histopathological finding was perivascular infiltration followed by peri-appendageal infiltration. CONCLUSION: Distinction between LS and AB appears to be unnecessary given their overlapping features.

Correlations between histopathologic and dermoscopic findings in Korean actinic keratosis.

Skin biopsy for AK diagnosis is usually performed on only a limited part of the whole lesion. Therefore, a clinical diagnosis is important. According to a study, there is no significant correlation between histopathological and clinical classification system. We examined the correlation between microscopic information and dermoscopic findings to deduce if dermoscopic information reflects histopathologic grade severity. Forty seven patients with histologically confirmed AK were enrolled and positive ratio of red pseudonetwork, rosette, red background and targetoid signs, white-to-yellow scale, white structureless area, and pigmentation from dermoscopic findings were investigated. Furthermore, viable epidermal thickness, vessel lumen dimensions, existence and thickness of ortho- and parakeratosis, degree of sola elastosis, flag sign existence, and Roewert-Huber classification were measured as histologic findings. Red background did not show a significant correlation with vascular dimension or viable epidermal thickness. When targetoid sign was present, vascular dimension was significantly larger but showed no correlation with viable epidermal thickness, parakeratosis or orthokeratosis. Solar elastosis level was significantly higher when white-to-yellow scale was present. According to Spearman's correlation analysis, ortho/parakeratotic thickness showed correlations with each other. The negative correlation between viable epidermal thickness and vascular dimension was also shown. Roewert-Huber histologic AK classification showed no correlation with any factors we checked. Factors considered to be characteristic features of AK in dermoscopy seemed unassociated with histologic AK classification and additional research is needed to determine degree of dysplasia of AK lesions using dermoscopy.

Demographic and clinical features of hidradenitis suppurativa in Korea.

Hidradenitis suppurativa (HS) is a chronic, relapsing, inflammatory skin disorder. Although several epidemiological studies have been conducted in Western countries, such data regarding Asian populations are scarce. In this study, we sought to investigate the demographic and clinical features of HS in Korea. A total of 438 patients, diagnosed with HS from May 2007 to April 2017, were enrolled and the electronic medical record of each patient was reviewed. Male patients were predominant with a male : female ratio of 2.5:1. Mean age of disease onset was 23.9 years and most patients had no family history. The most frequently affected area was the buttocks, followed by axillae and groin. Acne and diabetes mellitus were the most prevalent associated diseases and no patients with inflammatory bowel diseases were observed. In the univariable analysis, male patients had severe diseases compared with females with an odds ratio (OR) of 1.790. Two or more affected body regions were associated with HS severity with an OR of 1.693. While involvement of the perineum (OR, 4.067) and buttocks (OR, 1.471) tended to be associated with increased severity of the disease, the inguinal area (OR, 0.620) showed a tendency to be inversely associated with the severity. In multivariable analysis, identified risk factors were the involvement of the perineum (OR, 3.819) and buttocks (OR, 2.288). Smoking status and high body mass index seemed to be associated with more severe diseases. Our results will provide clinical characteristics of HS patients in Asia and help to broaden understanding of HS.

Low-fluence Q-switched Nd:YAG laser for the treatment of melasma in Asian patients.

BACKGROUND: Melasma is a common acquired facial pigmentary disorder that is resistant to various modalities of treatment. Recently, the low-fluence 1064-nm Q-switched neodymium-doped yttrium aluminum garnet laser (QSNY) has emerged as the new gold standard of melasma treatment in Asia. OBJECTIVE: To evaluate the efficacy and safety of low-fluence 1064-nm QSNY in Asian patients with melasma. METHODS: Data of patients with melasma treated with low-fluence QSNY in the department of dermatology at the Korea University Anam Hospital were reviewed retrospectively. A 1064-nm QSNY with 8 mm spot size and fluence of 1.2-2.0 J/cm2 at 10 Hz was used. The results were evaluated using the modified Melasma Area and Severity Index (mMASI) score and the physician's global assessment (PGA). RESULTS: A total of 40 Korean patients with Fitzpatrick skin type III to IV were included. Patients were treated for a median of 10 sessions at a median of 1-week intervals. The mean mMASI score decreased by 54.23% from a baseline of 3.19 ± 2.64 to 1.46 ± 1.06 after treatment. On PGA, 1 out of 40 patients (2.5%) showed excellent improvement, 14 (35%) good, 15 (37.5%) fair, 6 (15%) poor, and 4 (10%) no improvement. However, two patients showed mottled hypopigmentation and rebound hyperpigmentation. CONCLUSION: Low-fluence 1064-nm QSNY appears to be a safe and effective treatment for Asian patients with melasma.

Epidemiological and clinical features of rosacea in Korea: A multicenter cross-sectional study.

Rosacea is a common chronic inflammatory skin condition. Although several epidemiological and etiologic studies with large sample sizes have been conducted on Caucasians, such data regarding Asian populations are lacking. A total of 580 patients diagnosed with rosacea were enrolled from October 2014 to February 2015 at 14 general hospitals. Questionnaires, including the standard classification and grading system, were used for evaluation. The average age of the patients was 47.9 years. While 83.8% of patients revealed a single subtype, 16.2% of patients revealed mixed subtypes showing two or more subtypes simultaneously. Erythematotelangiectatic rosacea (ETR) was the most prevalent subtype. ETR combined with papulopustular rosacea showed the highest proportion in the mixed subtype group. Mild severity was revealed in 71.9% of patients. The most common aggravating factor was emotional changes (51.7%), followed by stress (48.4%). Approximately half of the patients (47.4%) showed relatively low awareness of rosacea. By identifying the epidemiological and etiologic features in Korea, we can suggest valuable clinical avenues for research, education and awareness among rosacea patients.

Features Causing Confusion between Basal Cell Carcinoma and Squamous Cell Carcinoma in Clinical Diagnosis.

BACKGROUND: Although squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) can be easily diagnosed clinically, proper diagnosis is sometimes difficult when based on clinical information alone. OBJECTIVE: To know what causes clinical misdiagnosis between SCC and BCC, and evaluate whether dermoscopy can improve diagnostic accuracy. METHODS: Clinical and dermoscopic photographs of inversely diagnosed cases (histologically confirmed BCC with a clinical impression of SCC or vice versa) were randomly presented to six dermatologists and the reasons for each correct or incorrect diagnosis were analyzed. RESULTS: Among 154 cases (SCCs or BCCs), 13 cases were inversely diagnosed; 9 SCCs were clinically misdiagnosed as BCC and 4 BCCs were clinically misdiagnosed as SCC. Clinically, scales, pigmentation and rolled border were meaningful factors to discern two carcinomas. Scales without both pigmentation and rolled border was favored for SCC, but BCC favored vice versa. Ulceration, telangiectasia and translucency contributed as confusing factors for proper diagnosis. Dermoscopy improved overall diagnostic accuracy to odds ratio 2.86. CONCLUSION: SCC has a higher tendency to be clinically misdiagnosed as BCC than vice versa. Pigmentation and rolled border are factors causing misdiagnosis of SCC as BCC and BCC may be misdiagnosed as SCC in the presence of scaling. Dermoscopy seems to improve the clinical diagnostic accuracy but has limitations for some ambiguous lesions.

Clinical experience of ingenol mebutate gel for the treatment of Bowen's disease.

There are only a few anecdotal case reports about Bowen's disease (BD) treated with ingenol mebutate (IM) gel but no clinical study has been published yet. The aim of this study was to evaluate the effectiveness of IM gel in the treatment of BD and to observe the therapeutic efficacy of IM alone or IM with ablative fractional laser pretreatment. Nineteen patients with BD or squamous cell carcinoma in situ confirmed by skin biopsy were enrolled. IM was applied with 0.015% gel on facial lesions for 3 days consecutively and 0.05% gel on other sites for 2 days consecutively, with a 5-mm application margin around the visible lesion. Nine patients applied IM gel immediately following fractional CO2 laser treatment. Two patients were lost to follow up and a total of 17 patients were enrolled. Nine patients (9/17, 52.9%) had a clinically complete response at 2 months after treatment. Among the patients treated with the fractional CO2 laser before applying IM gel, eight (8/9, 88.9%) showed a complete response and one (1/9, 11.1%) showed partial response. Among the patients treated with IM gel alone, only one patient (1/8, 12.5%) showed a complete response, four (4/8, 50%) showed a partial response and three (3/8, 37.5%) did not respond to therapy. IM gel alone seems to have limited value for treatment of BD; however, a combination therapy with the ablative fractional laser can increase its therapeutic effectiveness.

Relationship between skin color and solar elastosis in aged Asian skin: A colorimetric-pathologic correlation.

Aged skin is reported to be associated with unattractive skin color changes and solar elastosis. However, comparative studies have not documented the possible correlation between the two factors. This study investigated the plausible relationship between the facial skin color of elderly Asians and solar elastosis. A total of 22 skin specimens were collected from 22 Korean patients who underwent cheek skin biopsies. Skin color was quantitatively measured using colorimetric photography techniques to produce CIE L*a*b* values; the degree of solar elastosis was quantifiably assessed using a histologic grading scale. These values were used to investigate a correlation between the CIE L*a*b* coordinates and solar elastosis grade. The solar elastosis grade increased according to patient age (r = 0.67, p = .0006). However, the extent of solar elastosis was not statistically correlated with the CIE L*a*b* values, including L*, a*, and b* (r = 0.02, p = .95; r = 0.15, p = 0.50; r = -0.07, p = 0.76, respectively). The results showed that the solar elastosis grade increased, according to patient age, because of cumulative actinic damage. However, colorimetric skin color data did not correlate with the degree of solar elastosis. Therefore, cutaneous color changes and solar elastosis are separate, age-related phenomena. Physicians should be aware of the possible histologic changes in actinically damaged facial skin, regardless of the skin color.

Rosacea Subtypes Visually and Optically Distinct When Viewed with Parallel-Polarized Imaging Technique.

BACKGROUND: Parallel-polarized light (PPL) photography evaluates skin characteristics by analyzing light reflections from the skin surface. OBJECTIVE: The aim of this study was to determine the significance of quantitative analysis of PPL images in rosacea patients, and to provide a new objective evaluation method for use in clinical research and practice. METHODS: A total of 49 rosacea patients were enrolled. PPL images using green and white light emitting diodes (LEDs) were taken of the lesion and an adjacent normal area. The values from the PPL images were converted to CIELAB coordinates: L* corresponding to the brightness, a* to the red and green intensities, and b* to the yellow and blue intensities. RESULTS: A standard grading system showed negative correlations with L* (r=-0.67862, p=0.0108) and b* (r=-0.67862, p=0.0108), and a positive correlation with a* (r=0.64194, p=0.0180) with the green LEDs for papulopustular rosacea (PPR) types. The xerosis severity scale showed a positive correlation with L* (r=0.36709, p=0.0276) and a negative correlation with b* (r=-0.33068, p=0.0489) with the white LEDs for erythematotelangiectatic rosacea (ETR) types. In the ETR types, there was brighter lesional and normal skin with white LEDs and a higher score on the xerosis severity scale than the PPR types. CONCLUSION: This technique using PPL images is applicable to the quantitative and objective assessment of rosacea in clinical settings. In addition, the two main subtypes of ETR and PPR are distinct entities visually and optically.

Analysis of Korean acne patients according to age groups based on two multicenter studies.

Along with increasing public concerns on acne and its complications, increasing treatment options seem to lead more acne patients to clinics globally, including Korea. The aim of the present study was to investigate the number and distribution of acne patients according to age group by analyzing number and age of outpatients from several general hospitals in Korea. Two retrospective multicenter studies including 14 general hospitals for a maximum of 10 years were conducted by medical chart review of acne patients. During the last 10 years, total acne patients have increased by 60% in number and patients under the age of 19 years have doubled. Adult acne patients (aged >18 years) accounted for the biggest portion in total acne patients at over 80%. Although upper grade of elementary school patients (aged 10-12 years) accounted for the biggest portion among the childhood acne patients, children under 10 years have also increased rapidly by 73% during the last 10 years. Childhood acne patients (aged <13 years) accounted for 11% of total acne patients. We found that acne patients were increasing consistently and the portion of those aged under 19 years is getting bigger. Additionally, childhood acne patients have increased remarkably.

Characteristics and Clinical Manifestations of Pigmented Purpuric Dermatosis.

BACKGROUND: Pigmented purpuric dermatoses (PPD) are a spectrum of disorders characterized by a distinct purpuric rash. Although PPD can be easily diagnosed, the disease entity remains an enigma and a therapeutic challenge. OBJECTIVE: The purpose of this study was to investigate the characteristics and clinical manifestations of PPD and to elucidate the relationship between assumed etiologic factors and the clinical manifestations of PPD and treatment responses. METHODS: Retrograde analyses were performed to identify appropriate PPD patients who visited Korea University Medical Center Anam Hospital from 2002 to 2012. RESULTS: Information on 113 patients with PPD was analyzed, and 38 subjects with skin biopsy were included for this study. Schamberg's disease was the most frequent clinical type (60.5%). Concomitant diseases included hypertension (15.8%), diabetes (10.5%), and others. Associated medication histories included statins (13.2%), beta blockers (10.5%), and others. Possibly associated etiologic factors were recent upper respiratory infection (5.3%), high orthostatic pressure due to prolonged standing (2.6%), and strenuous exercise (2.6%). A total of 36 patients (94.7%) were treated with one or more treatment methods, including oral antihistamines, pentoxifylline, topical steroids, and/or phototherapy. There was no significant difference in disease progress according to underlying diseases, medications, or association factors (p>0.05). CONCLUSION: Our overall results were grossly consistent with the existing literature, excluding several findings. Although a possible relationship between PPD and cardiovascular disease or cardiovascular medication was proposed at the beginning of the study, no statistically significant correlations were found according to the specific clinical types and treatment responses (p>0.05).