Pigmented contact dermatitis and hair dyes: A retrospective case-control multicentre study in Korea.

BACKGROUND: Pigmented contact dermatitis (PCD), a rare variant of non-eczematous contact dermatitis, is clinically characterized by sudden-onset brown or grey pigmentation on the face and neck. It is hypothesized to be caused by repeated contact with low levels of allergens. OBJECTIVES: This study evaluated the risk of using hair dyes in patients with PCD in Korea. METHODS: A total of 1033 PCD patients and 1366 controls from 31 university hospitals were retrospectively recruited. We collected and analysed the data from the patient group, diagnosed through typical clinical findings of PCD and the control group, which comprised age/sex-matched patients who visited the participating hospitals with pre-existing skin diseases other than current allergic disease or PCD. RESULTS: Melasma and photosensitivity were significantly more common in the control group, and a history of contact dermatitis was more common in the PCD group. There were significantly more Fitzpatrick skin type V participants in the PCD group than in the control group. There was no significant difference in sunscreen use between the groups. Using dermatologic medical history, Fitzpatrick skin type and sunscreen use as covariates, we showed that hair dye use carried a higher PCD risk (odds ratio [OR] before adjustment: 2.06, confidence interval [CI]: 1.60-2.65; OR after adjustment: 2.74, CI: 1.88-4.00). Moreover, henna users had a higher risk of PCD (OR before adjustment: 5.51, CI: 4.07-7.47; OR after adjustment: 7.02, CI: 4.59-10.74), indicating a significant increase in the risk of PCD with henna dye use. Contact dermatitis history was more prevalent in henna users than in those using other hair dyes in the PCD group (17.23% vs. 11.55%). CONCLUSION: Hair dye use is a risk factor for PCD. The risk significantly increased when henna hair dye was used by those with a history of contact dermatitis.

Efficacy of skin rejuvenation with a fractional 1927-nm thulium laser alone or combined with a chemical peel: a controlled histopathological preliminary study in a mouse model.

Many patients demand minimally invasive treatments for skin rejuvenation, such as nonablative laser and superficial chemical peels. Combination therapy yet has not been studied histopathologically. The purpose of this study is to assess the histopathological efficacy of a 1927-nm thulium laser-assisted salicylic acid (SA) peel in skin rejuvenation. A six-segment table was drawn on the shaved back of C57BL/6 mouse. All segments were irradiated with the thulium laser-different tips and passes were used for specific segments. A 30% SA peel was then applied to the right-hand segments. After treatment, the skin samples were collected from each segment and examined for dermal thickness, collagen density, and melanin content. Greater thickness was seen in the combination therapy group compared with the laser alone group and in those segments receiving more passes with larger beam-sized tip. Collagen density increased in all treated skin segments, irrespective of the group. No adverse events were noted in the treated areas. The sample size was small and mouse skin has histological differences with human skin. The combination of a thulium laser and 30% SA peel has a synergistic effect on dermal thickness, so that can be suggested as a novel skin rejuvenation technique.

Skin rejuvenating effect of a combined triple-wavelength (755 nm, 810 nm, and 1064 nm) laser: a preliminary study.

With an increasing demand for noninvasive skin rejuvenation techniques, several light-based devices have been introduced. Due to its ability to deliver thermal energy from the superficial to deeper levels of the dermis, a combined triple-wavelength laser (755 nm, 810 nm, and 1064 nm) can be used for skin rejuvenation. The objective of this study was to assess the effectiveness and safety of a combined triple-wavelength laser for skin rejuvenation. A total of 28 female patients seeking skin rejuvenation treatment were included. All patients underwent five consecutive treatment sessions at a two-week interval. Clinical improvement of aging-related cutaneous change was noted by the treating dermatologists and patients. Biopsies were performed on the faces of consenting patients before and two weeks after the final treatment. Significant clinical improvements were observed by both patients and evaluating dermatologists. Based on the patient satisfaction questionnaire, 78% of patients reported a self-assessed improvement of more than 25%. Additionally, 86% of patients showed an improvement of more than 25% on objective assessment by dermatologists. Histopathological findings revealed increased collagen and elastic bundles throughout the dermis. Except for transient pain during treatment, no serious adverse effects were reported. The findings of this study suggest that the combined triple-wavelength laser may be an effective and safe nonablative option for skin rejuvenation.

Can we predict postinflammatory hyperpigmentation after laser treatment based on dermoscopic findings of solar lentigo?

Solar lentigo (SL) commonly occurs as hyperpigmented macules in areas exposed to ultraviolet radiation. It typically shows an increased number of melanocytes in the basal cell layer of the skin, with or without elongated rete ridges. This retrospective study aimed to evaluate the characteristic dermoscopic patterns, reflecting different histopathological features, which might be valuable in predicting the possibility of postinflammatory hyperpigmentation (PIH) occurring after laser treatment. In total, 88 Korean patients diagnosed with biopsy-proven SL (a total of 90 lesions were diagnosed) between January, 2016 and December, 2021 were included. Histopathological patterns were classified into six categories. Dermoscopic features were classified into six categories. Pseudonetwork pattern and rete ridge elongation showed a statistically significant negative correlation. This means that a flatter epidermis is likely to manifest as a pseudonetwork pattern. The erythema pattern showed a significant positive correlation with interface changes and inflammatory infiltration. Bluish-gray granules (peppering), a characteristic dermoscopic finding, showed significant positive correlations with interface changes, inflammatory infiltration, and dermal melanophages. Clinicians considering laser treatment for patients with SL should perform dermoscopic tests before treatment. The pseudonetwork relates to flattened epidermis and fewer Langerhans cells; thus, a lower remission of PIH after laser treatment might be expected. If bluish-gray granules or erythema are observed, inflammatory conditions are likely to be involved. In such cases, regression of the inflammatory response through drug therapy, such as topical corticosteroids, should be a priority option before laser treatment.

Can a radiofrequency device reduce the pore size?

A facial pore is an empty funnel-shaped structure filled with cornified cylindrical plugs that can be cosmetically bothersome to some patients. In the previous report, the new unipolar radiofrequency (RF) device with a vacuum showed excellent skin tightening and patient satisfaction with improved pores. This study aims to confirm the treatment's efficacy with the new unipolar RF device on facial dilated pores by measuring quantitative sebum production differences and doing a histologic examination of pore size. Twelve patients who visited the dermatologic clinic without other underlying inflammatory facial skin diseases were included, regardless of the patient's age or sex. All patients received five successive treatments at 2-week intervals. We assessed all changes in sebum production levels, melanin index, erythema index before and after treatment, along with overall improvement (reduction of pore size, skin tone, skin texture, and skin laxity). In the five patients who agreed in advance, a biopsy of the pore lesion was taken before and 1 month after the last treatment with hematoxylin and eosin (H&E) staining, Masson's trichrome (M-T) staining, and Victoria blue staining. We observed a significant reduction of sebum production and melanin index after using the new unipolar RF device with a vacuum (sebum production, p = 0.011; MI, p = 0.004). In evaluating patient satisfaction for four categories, the patients showed a moderate to the excellent improvement of more than 50% in their condition except for skin tones. The average pore size decreased by 41.7% in the histological examination, from 64.98 to 37.86 µm. Additionally, we observed an overall decreased sebaceous gland in the dermis and the proliferation of dermal collagen fiber. The number of elastic bundles in the D-E junction was increased after treatment. The nonablative unipolar RF devices with a vacuum can improve dilated pores with a dual mechanism (collagen regeneration and reduction of sebum production), with much less pain than other RF devices.

Efficacy and safety of intense pulsed light using a dual-band filter for the treatment of facial acne vulgaris.

Intense pulsed light (IPL) devices have been used in acne treatment in combination with conventional topical and oral medications. This study aimed to evaluate the efficacy and safety of IPL treatment using a dual-band filter (400-600 nm and 800-1200 nm) in facial acne vulgaris treatment. Twenty-three acne vulgaris patients were enrolled in this study. The patients were treated on both sides of the face. The treatments were performed in 2-week intervals for a total of five sessions. The final visit for the clinical evaluation was 2 weeks after the fifth treatment session. The mean number of papules, pustules, and comedones, and the melanin index, was significantly decreased at the final visit. However, sebum production and the erythema index showed no statistically significant differences after treatment. IPL treatment using a dual-band filter can be an alternative for patients who are unfit for systemic acne medication. It can also be used with conventional acne treatment for better treatment results.

Photothermal therapy using gold nanoparticles for acne in Asian patients: A preliminary study.

Acne is a common skin disease that occurs in pilosebaceous units and is often prevalent in adolescence. There are many acne treatments, but they are associated with side effects, such as antibiotic resistance, teratogenicity, and irritation. Therefore, it is necessary to develop a more effective and safe alternative treatment for managing acne in patients of all ages. This study aimed to confirm the effect of gold photothermal therapy for acne. About 12 patients who visited the dermatologic clinic with moderate to severe acne vulgaris were included in the study, regardless of age or sex. All patients received three successive treatments at 1- to 2-week intervals with a photopneumatic device after applying the contents of a gold nanoparticle ample to the skin. Changes in the number of papules, pustules, and comedones before and after treatment, along with the overall improvement, were assessed. In four patients, a biopsy was taken before and 1 month after the last treatment. Significant reductions in acne lesions were observed after the use of gold photothermal therapy (papules, P = .001; pustules, P < .001; and comedones, P = .001). As noted in the Physician Global Assessment, the patients showed an average improvement of more than 50% in their condition. In the histopathological findings, a decrease in inflammatory cell infiltration and fibrotic changes of the dermis were observed after gold photothermal therapy. Gold photothermal therapy showed significant clinical and histological improvements in acne vulgaris in Asians without serious adverse effects.

Therapeutic effects of a new invasive pulsed-type bipolar radiofrequency for facial erythema associated with acne vulgaris and rosacea.

Facial erythema from rosacea and acne is one of the most common problems encountered in dermatologic clinics. Effective therapeutic interventions for persistent erythema, which can cause patients frustration and psychological distress, are needed. The aim of this study was to evaluate the efficacy and safety of an invasive short pulsed-type bipolar radiofrequency device (IPBRF) for the treatment of intractable facial erythema. Thirty-one patients who had been diagnosed with rosacea or acne vulgaris and combined erythema underwent at least two IPBRF treatment sessions (maximum: 5) at 2-week intervals. Treatment outcomes were evaluated by investigator global assessment (IGA) based on clinical photographs, patient global assessment (PGA) score, and skin biophysical parameters including erythema index (EI), melanin index (MI), and transepidermal water loss (TEWL). Most patients showed significant clinical improvement. IGA scores for erythema, pores and smoothness improved after treatment. PGA also showed a trend toward improvement. Mean EI was significantly improved after the second treatment compared to baseline, which maintained until the study period. MI and TEWL showed a tendency toward improvement. There were no serious adverse events reported during the study. IPBRF led to rapid clinical improvement in facial erythema associated with rosacea and acne vulgaris and could be an effective and safe treatment option.

"New classification of late and delayed complications after dermal filler: Localized or Generalized?"

Background: As filler injections have become very common procedures worldwide, the number of complications has increased. However, there is a lack of systematized studies and precise classification of late and delayed complications. This study aimed to suggest new and reliable classifications and to characterize the clinical manifestations of late and delayed complications after filler injections.Methods: This retrospective study analyzed patients and suggested a new classification of delayed adverse effects related to filler injection. Several demographic and clinical findings were analyzed. Patients were classified into two types according to their clinical presentation: Type I (Localized) or Type II (Generalized).Results: Twenty-five patients were evaluated during a clinically active adverse event suspected to be related to fillers. The most common injected filler substance was hyaluronic acid (HA, 68.8%). 76% of the patients were classified with Localized complications. In the Generalized complications group, systemic symptoms were more common (p=0.002), the treatment response was poor (p=0.010), and fewer patients showed complete remission (p=0.007) than in the Localized complications group.Conclusions: We propose a simple new classification method for late and delayed complications after dermal filler: Localized and Generalized. We expect that this new classification could help provide appropriate treatment and predict patient prognosis.

Comparative efficacy of short-pulsed intense pulsed light and pulsed dye laser to treat rosacea.

Background: Laser and light-based therapies have often been used successfully to treat rosacea. Recently, short-pulsed intense pulsed light (IPL) that emitted pulse durations down to 0.5 ms was found to be effective for rosacea treatment. Objective: This study evaluated the efficacy of short-pulsed IPL in the treatment of rosacea compared with pulsed dye laser (PDL) using same pulse duration and fluence. Materials and Methods: Nine patients with rosacea were enrolled in a randomized, split-face trial. Each treatment consisted of four sessions at three-week intervals and followed up until three weeks after the last treatment. Efficacy was assessed by erythema, melanin index, physician's subjective evaluation, and patient's satisfaction. Results: The mean change in erythema index was -4.93 ± 1.59 for the short-pulsed IPL group and -4.27 ± 1.23 for the PDL group. The mean change in melanin index was -2.52 ± 2.45 for the short-pulsed IPL group and -1.95 ± 1.41 for the PDL group. There was no significant difference in either melanin or erythema index between short-pulsed IPL and PDL treatments, and there were no noticeable adverse events. Conclusions: There was no significant difference between PDL and short-pulsed IPL treatment using the same energies and pulse. Both PDL and short-pulsed IPL were satisfactory and safe for rosacea treatment.

Double stacking cryolipolysis treatment of the abdominal fat with use of a novel contoured applicator.

Background: Cryolipolysis is a noninvasive method for the selective reduction of subcutaneous fat. The abdomen and flank area are most commonly treated sites and now the treatment efficacy became the important issue. Objectives: To evaluate the effectiveness and safety of double stacking cryolipolysis treatment with the novel contoured applicator for abdominal fat reduction. Materials and methods: 12 healthy Korean were treated using cryolipolysis contact device. The device was applied on participant's left lower abdomen. Performance was held for 35 minutes and immediately repeated the second performance. The right abdomen was left untreated. Participants were examined with high resolution ultrasound and the depth of subcutaneous fat layer was measured initially and 8 weeks after the sessions. Any adverse events were assessed during the entire study period. Results: The subjective reduction of abdominal fat was noted in most participants. No serious adverse events was reported. Reduction of subcutaneous fat layer depth was confirmed in high resolution ultrasound after 8 weeks of treatment. Conclusion: The results of this study indicate that abdominal fat can be reduced effectively by the novel cryolipolysis applicator. With subjective satisfaction of participants our study shows that double stacking treatment appears safe and well tolerated with enhanced treatment outcomes.

Comparative effects of various absorbable threads in a rat model.

BACKGROUND: Conventional procedures including botulinum toxin and filler injections have their limitations in improving deep wrinkles and decreasing tissue laxity, and possess the propensity for vascular accidents. Absorbable thread is a recently commercialized field, but there is little evidence on comparative superiority. OBJECTIVES: We observed the effects of polydiaxanone (PDO) threads with different number of strands in relation to collagen production and histopathology in a rat model. MATERIALS AND METHODS: Dorsal skin of rat was divided into five different compartments and four different PDO threads and monofilament poly-lactic acid (PLA) thread were inserted. Tissue samples were obtained at week 1, 2, and 12 after the procedure for histopathologic review and real-time PCR for quantification of collagen. RESULTS: Multiple PDO filaments produced more collagen at 2 weeks. Single-stranded PLA thread insertion resulted in more Col1α1 levels than the double PDO thread and also showed the most Col1α3 production at week 2. The amount of collagen showed a sharp decline at week 12. Histologic evaluation showed retained threads surrounded by fibrous capsule-like structure at week 12. CONCLUSION: We were able to observe more collagen production in multiple stranded PDO threads compared to a single strand and that increasing number of threads leads to more collagen synthesis.

Cryolipolysis for submental fat reduction in Asians.

BACKGROUND: Cryolipolysis is a noninvasive method for the selective reduction of fat, especially proven to be safe and effective in body contouring. There is a demand for reduction in submental fat, which is related not only with a favorable appearance but also with signs of aging. OBJECTIVE: This study evaluated the efficacy and safety of cryolipolysis for subcutaneous fat reduction in the submental area in Asians. MATERIALS AND METHODS: Ten healthy Koreans were treated using a cryolipolysis contact device (CoolMini applicator, Zeltiq Aesthetics). The device was applied on the participant's neck twice via two lateral approaches. Patient's body weight was measured, and photographs were taken at baseline and during the follow-up visit after 8 weeks. Participants were examined with ultrasound and the depth of the subcutaneous fat layer was measured. RESULTS: The subjective reduction of submental fat was noted in most of the participants. Reduction of the subcutaneous fat layer depth was confirmed by ultrasound after 8 weeks of treatment. CONCLUSION: The results of this study indicate that submental fat can be safely and effectively reduced with use of a cryolipolysis applicator. The present study shows that cryolipolysis can be an option for nonsurgical facial contouring.

Safety and efficacy of a non-contact radiofrequency device for body contouring in Asians.

BACKGROUND: The non-invasive reduction of subcutaneous abdominal fat became popular. Radiofrequency, non-contact, selective-field device Vanquish® has been developed to selectively induce deep fat tissue heating to reduce waist circumference. OBJECTIVE: The objective of this study was to evaluate the efficacy and safety of clinical, radiological results of the radiofrequency, non-contact, selective-field device treatment. METHODS: Twelve healthy individuals with no underlying medical problem were treated with five sessions of radiofrequency treatment to reduce abdominal subcutaneous fat. 45-minute sessions were performed with an 1-week interval. For efficacy evaluation, patient's abdominal circumferences and body weight were measured, and photographs were taken at baseline and each follow-up visit for 12 weeks. One subject was examined with computed tomography (CT) before the first session and six weeks after the first CT scan, and we measured the volume of subcutaneous fat layer. Any adverse effect was assessed during the entire study period. RESULTS: Reduction in abdominal circumferences was noted in most participants (10 of 12 patients). No serious adverse effect was reported. Volume reduction of abdominal subcutaneous fat layer was confirmed in a subject who took CT scan. CONCLUSIONS: Our study shows that the selective-field radiofrequency treatment seems to be safe and efficient for reduction of abdominal subcutaneous fat.

Comparative study of dual-pulsed 1064 nm Q-switched Nd:YAG laser and single-pulsed 1064 nm Q-switched Nd:YAG laser by using zebrafish model and prospective split-face analysis of facial melasma.

BACKGROUND: Recently dual-pulsed low-fluence 1064-nm Q-switched Nd:YAG (QSNY) laser has been developed for reducing complication during melasma treatment. OBJECTIVE: Comparison of the efficacy and safety between dual-pulsed mode and single-pulsed mode for the treatment of melasma. MATERIALS AND METHODS: In preclinical study, adult zebrafish were irradiated with dual-pulsed and single-pulsed mode. Changes of melanophore and cell death were assessed. In split-face clinical study, dual-pulsed and single-pulsed mode were irradiated on the left and right side of the face, respectively. L* value, clinical digital photos, modified Melasma Area and Severity Index (MASI) scores, and side effects were measured. RESULTS: As compared to single-pulsed mode and dual-pulsed mode with longer intervals, zebrafish melanophore was cleared quickly at dual-pulsed mode with 80-µsec interval and 0.3 J/cm2 fluence. Dual-pulsed mode showed the least regeneration of melanophore at 4 weeks after irradiation and no cell death was observed with 80-µsec interval. Both pulse modes improved melasma significantly but modified MASI score and L* value were not significantly different between each other. Lesser pain and shorter duration of post-laser erythema were observed with dual-pulsed mode. CONCLUSION: Dual-pulsed mode was as effective as single-pulsed mode for the treatment of melasma and revealed less side effects.

A case of motor neuropathy after cryolipolysis of the arm.

Cryolipolysis treatment is a non-invasive option for localized fat reduction without damaging the surrounding tissue. Clinical studies about cryolipolysis show various side effects, including temporary erythema, bruising, and transient numbness. But, no reports are available on motor nerve malfunction after cryolipolysis. A 24-year-old female received cryolipolysis treatment on abdomen, both arms. After 10 days, patient complained of weakness and inability to lift heavy objects. Symptoms continued for 6 months, and fully recovered without treatment. Thus, we report a case of motor neuropathy after cryolipolysis, which is a rare complication of cryolipolysis.

Non-invasive cryolipolysis to reduce subcutaneous fat in the arms.

BACKGROUND: Cryolipolysis received U.S. Food and Drug Administration clearance for reducing fat from the flanks, abdomen, and thighs. The upper arms are an off-label indication for cryolipolysis, and outcome data on reducing fat from the arms using a cryolipolytic device has rarely been published. OBJECTIVE: This pilot study evaluated cryolipolysis to reduce upper arm fat. MATERIALS AND METHODS: A flat vacuum applicator was used to treat seven subjects in a single-side study. The patients underwent one cycle of upper-arm cryolipolysis treatment, and the contralateral arm served as a control. Follow-up was conducted at 8 weeks. Equalization treatments were delivered subsequently to the opposite arm. Efficacy was evaluated by ultrasound imaging, physician's assessment, and patient satisfaction. Side effects and adverse events were monitored. RESULTS: Ultrasound measurements showed a decrease in the fat layer at 83.3% of the 12 measured sites. The mean reduction in fat layer thickness was 15.3%, corresponding to 2.03 mm. A significant difference was detected between baseline and 8-week assessments (p = 0.001). CONCLUSION: One treatment using a flat vacuum cryolipolysis applicator was safe and effective to reduce arm fat.

Dermal Remodeling of Burn Scar by Fractional CO2 Laser.

BACKGROUND: Ablative CO2 fractional lasers have recently been introduced for burn scar treatment because of pronounced clinical outcomes with fewer treatment sessions than nonablative fractional laser. OBJECTIVE: This study was conducted to observe clinical as well as histologic changes of burn scars after treatment with CO2 fractional laser. MATERIALS AND METHODS: Eleven patients (one female and 10 males, aged 31-59 years) with skin phototypes III to V with burn scars received 10 sessions of fractional CO2 laser treatments (UltraPulse(®) Encore; Lumenis, Santa Clara, CA, USA) over an average 5-week interval. Two passes were performed using the following parameters: deep FX mode, 12.5-30 mJ, with a density setting of 5-10 %. Clinical evaluations by three blinded dermatologists were obtained at baseline and at 6 months after the final treatment via photographs using the Vancouver scar scale (VSS). Skin biopsies were done on four patients before and after treatment. RESULTS: All patients showed clinical improvement in their scars with significant decrease in VSS. Histologic findings showed the changes in the upper dermis with newly formed dermal papilla. This characteristic upper dermis change was presented as improvement in surface smoothness and skin tension clinically. Postinflammatory hyperpigmentation and itching sensation were the most common adverse effects. CONCLUSION: Burn scar treatment by fractional CO2 laser is effective by forming new collagen fibers mainly in the upper dermis. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

IL-33 induces Egr-1-dependent TSLP expression via the MAPK pathways in human keratinocytes.

Atopic dermatitis (AD) is a chronic inflammatory skin disease in which T-helper type 2 (Th2)-type immune responses are dominant. Th2 cytokine, interleukin (IL)-33 and thymic stromal lymphopoietin (TSLP) have been suggested to have an important role in AD. IL-33 is highly expressed in AD, but its role in AD has not yet been fully understood. To further identify the role of IL-33 in AD, we investigated the expression of TSLP induced by IL-33 in keratinocytes. This study revealed that IL-33 induced TSLP expression in human keratinocytes. Early growth response protein 1 (Egr)-1, which is an inflammatory transcriptional factor, is induced by IL-33. IL-33-mediated TSLP induction in keratinocytes was suppressed by treatment with mitogen-activated protein kinase (MAPK) inhibitors or small interfering RNA against Egr-1. Chromatin immunoprecipitation (ChIP) assay indicated the direct involvement of Egr-1 in IL-33-mediated TSLP induction. Taken together, these findings indicate that IL-33 may increase TSLP expression through an Egr-1-dependent mechanism via ERK1/2, JNK and p38 activation in keratinocytes. These data suggest that the IL-33-ERK/JNK/p38/Egr-1/TSLP axis is involved in allergic skin Th2 inflammation, and it may be a novel therapeutic target.