Seok Kweon Yun

Suction device for epidermal grafting in vitiligo: employing a syringe and a manometer to provide an adequate negative pressure.

Background. Suction devices for epidermal grafting need a suction pump to provide a negative pressure. The authors have developed a suction device in which a syringe and a manometer are employed to provide a negative pressure. Objective. The purpose of this study was to evaluate the efficacy of our suction device in vitiligo patients. Methods. The suction device was used to obtain epidermal blisters from the donor site. A CO2 laser was employed to remove the depigmented epidermis. The blister roofs of the donor site were harvested and were placed onto the recipient area. Ten patients with stable vitiligo were treated by epidermal grafting. Results. Epidermal blisters were produced by suction in all patients. Also, all 10 patients regained repigmentation. Conclusion. Our suction blister device is simple and inexpensive to make, and it may become an alternative to the other suction devices.

Tinea Incognito in Korea and Its Risk Factors: Nine-Year Multicenter Survey

Tinea incognito (TI) is a dermatophytic infection which has lost its typical clinical appearance because of improper use of steroids or calcineurin inhibitors. The incidence of TI is increasing nowadays. We conducted retrospective review on 283 patients with TI from 25 dermatology training hospitals in Korea from 2002-2010 to investigate the demographical, clinical, and mycological characteristics of TI, and to determine the associated risk factors. More than half (59.3%) patients were previously treated by non-dermatologists or self-treated. The mean duration of TI was 15.0 ± 25.3 months. The most common clinical manifestations were eczema-like lesion, psoriasis-like, and lupus erythematosus-like lesion. The trunk and face were frequently involved, and 91 patients (32.2%) also had coexisting fungal infections. Among 67 isolated strains, Trichophyton rubrum was the most frequently detected (73.1%). This is the largest study of TI reported to date and the first investigational report concerning TI in Korea. We suggest that doctors should consider TI when a patient has intractable eczema-like lesions accompanied by tinea pedis/unguium. Furthermore, there should be a policy change, which would make over-the-counter high-potency topical steroids less accessible in some countries, including Korea.

Treatment of Angiofibromas in Tuberous Sclerosis Complex: The Effect of Topical Rapamycin and Concomitant Laser Therapy

Facial angiofibromas are the most troublesome cutaneous manifestations of the tuberous sclerosis complex and are difficult to treat. Lasers are most commonly used to treat these skin lesions, but results are disappointing with frequent recurrences. Recently, treatment of facial angiofibromas with topical rapamycin has been reported to yield promising results. We observed the need of laser ablation in addition to topical rapamycin to get best results for the treatment of angiofibromas in 4 cases. The result showed that topical rapamycin ointment was enough when the papules were yet small in size, i.e. less than a few millimeters, but additional laser ablation was needed for large papules approximately larger than 4 mm. Considering the natural course of facial angiofibromas, we believe that topical rapamycin can be best used in childhood patients. In adults, topical rapamycin was useful for treating the still present small papules and for preventing recurrences after laser treatment.

Saponified Evening Primrose Oil Reduces Melanogenesis in B16 Melanoma Cells and Reduces UV-Induced Skin Pigmentation in Humans

This study was conducted to determine whether saponified evening primrose oil (sap-EPO) has the potential for use as a whitening agent and to investigate its underlying mechanisms of action. In B16 melanoma cells, sap-EPO dose-dependently inhibited isobutylmethylxanthine-induced melanogenesis with no cytotoxicity. This decrease in melanin production was correlated with reduced enzyme activity and decreased mRNA and protein levels of tyrosinase. The mRNA levels of tyrosinase-related proteins 1 and 2 decreased in response to treatment with sap-EPO, indicating that it regulated tyrosinase at the transcriptional level. Expression of microphthalmia-associated transcription factor was also decreased by sap-EPO as evidenced by decreased mRNA and protein levels. Additionally, topical application of sap-EPO resulted in efficient whitening of UVB-induced hyperpigmentation of human skin. Taken together, these results suggest that sap-EPO has the potential for use as a cosmetic whitening agent.

Squamous eddies in irritated seborrheic keratosis.

Seborrheic keratosis is related to the intraepidermal hair follicle in its morphogenesis. Squamous eddies in irritated seborrheic keratosis (ISK) are known to develop by focal maturation of basaloid cells, but the significance of squamous eddies is not understood. The purpose of this study was to elucidate the nature of squamous eddies in ISK. Serial sections of paraffin blocks of 20 cases of ISK were examined. We tracked each squamous eddy through the serial sections to observe the different shapes and positions of the same squamous eddy. In 4 cases, squamous eddies revealed hair shafts at their centers in different sections. In 14 cases, squamous eddies contained acrotrichial canals. In 13 cases, squamous eddies were connected to keratotic invaginations we thought to be follicular infundibula. Eighteen of the 20 cases of ISK showed at least 1 of the morphological features of intraepidermal hair follicle structures. We have found that the squamous eddies of ISK are anatomically related to acrotrichia.

Basal cell carcinoma arising in a tattooed eyebrow.

Malignant skin tumors, including squamous cell carcinoma and malignant melanoma, have occurred in tattoos. Seven documented cases of basal cell carcinoma associated with tattoos have also been reported in the medical literature. We encountered a patient with basal cell carcinoma in a tattooed eyebrow. We report on this case as the eighth reported case of a patient with basal cell carcinoma arising in a tattooed area.

Unilateral Beau's Lines Associatd with a Fingertip Crushing Injury

Beaus lines are transverse depressions or ridgings of the nail surface that are the result of the temporary arrest of nail matrix formation. They are caused by systemic diseases, local trauma, drugs, and infection. Generally, Beaus lines after a fingertip injury occur on only the affected finger, not on the unilateral extremity. In this report, we present the case of a 36‐year‐old man who developed transverse ridgings in the nail plates of all five fingers of the affected extremity after a fingertip (thumb) crushing injury. During the follow up, the growth rate of affected fingernails was normal. The transverse ridgings advanced with the linear growth of the nails and eventually disappeared. To the best of our knowledge, no association between unilateral Beaus lines and fingertip injury has been reported in the English literature.

Basal Cell Carcinoma on the Pubic Area: Report of a Case and Review of 19 Korean Cases of BCC from Non-sun-exposed Areas.

Basal cell carcinoma (BCC) is one of the most commonly diagnosed malignant skin tumors and develops characteristically on sun-exposed areas, such as the head and neck. Ultraviolet light exposure is an important etiologic factor in BCCs, and BCCs arising from non-sun- exposed areas are, therefore, very rare. In particular, the axilla, nipple, the genital and perianal areas are not likely to be exposed to ultraviolet light; thus, if BCC develops in these areas, other predisposing factors should be considered. Herein, we report a case of BCC arising on the pubic area in a 70-year-old man. We also performed a survey of the literature and discussed the 19 cases of BCC from non-sun-exposed areas reported to date in Korea.

Trichoscopic Findings of Hair Loss in Koreans.

Background Trichoscopic findings of hair loss have been well described for the differential diagnosis of alopecia; however, critical findings were not thoroughly investigated or compared among all ethnic groups, including Asians. Objective We aimed to find any characteristic trichoscopic findings in Korean alopecia patients and to verify whether those findings are closely related to previously reported observations. Methods Three hundred and twenty-seven patients with hair loss of various causes and 160 normal scalps were analyzed. Trichoscopic examination was performed with a polarized-light handheld dermoscope. Results A total of 35 patterns of trichoscopic features were represented, and certain features were significantly common or observed exclusively in a particular type of alopecia as follows: yellow dots, exclamation mark hairs, and proximal tapering hairs (alopecia areata), trichoptilosis and pointed hairs (trichotillomania), corkscrew hairs, septate hyphae hairs, and comma hairs (tinea capitis), diffuse white area, fibrotic white dots, and tufting hairs (primary cicatricial alopecia), hair diameter diversity and peripilar sign (androgenetic alopecia), and short nonvellus hairs (telogen effluvium). Conclusion The characteristic trichoscopic features for the differential diagnosis of alopecia in Koreans, shown as follicular, perifollicular, and hair shaft patterns, are similar to those of Caucasians; however, the frequencies of the pigment patterns are different between Koreans and Caucasians because of the contrast effect of the skin and hair color. Therefore, racial difference should be considered in the trichoscopic evaluation for differential diagnosis.

Eczema herpeticum localized to area of tinea cruris.

Eczema herpeticum (EH) has been reported in association with various skin abnormalities. We experienced a patient with tinea cruris who developed EH within a fungal infection. To our knowledge, dermatophyte infection as an underlying cutaneous disorder for EH has not been previously described in the English literature.