A quantitative evaluation of pigmented skin lesions using the L*a*b* color coordinates.
The evaluation of pigmentary skin lesions by clinical doctors has been based on subjective and qualitative judgements. Observations have mostly relied on visual inspection, making the effects of treatment difficult to evaluate with any precision. For this reason there is a real need for an objective method to evaluate prognosis after treatment. Recent scientific measurements such as reflectance spectrophotometry and reflectance colorimetry have provided accurate quantitative color information about skin lesions, but these techniques are costly and difficult to apply in the clinical field. The purpose of this study was to develop a simple and cost-effective way of evaluating treatment results. We have developed a software program using the L*a*b* color coordinate system to quantify the effect of treatment and have successfully demonstrated its clinical usefulness. Our method compares the relative color difference between normal skin and skin lesions before and after treatment, instead of measuring the absolute color of skin lesions. The accuracy of our quantitative color analysis was confirmed by the simulated images of hemangioma and ota nevus. Clinical efficacy was also confirmed through a blind test involving 3 clinicians who were asked to grade the treatment effects of 13 cases of hemangioma and 7 cases of ota nevus. These subjective clinical grades correlated well with the treatment results obtained using the proposed color analysis system (Correlation coefficient = 0.84). (+info)
A case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota.
The Sturge-Weber syndrome consists of a unilateral port-wine hemangioma of the skin along the trigeminal distribution and is accompanied by an ipsilateral leptomeningeal angioma. Glaucoma is present in approximately half of the cases. The Nevus of Ota is a melanocytic pigmentary disorder, most commonly involving the area innervated by the trigeminal nerve. Elevated intraocular pressure, with or without glaucomatous damage, is observed in 10% of the cases. We report the first case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota in Korea. (+info)
Effect of Q-switched alexandrite laser irradiation on dermal melanocytes of nevus of Ota.
OBJECTIVE: To investigate the effect of Q-switched alexandrite laser irradiation on dermal melanocytes of nevus of Ota. METHODS: Multiple biopsies were carried out on 4 patients with nevus of Ota before and after laser irradiation. Altogether 11 samples were examined under light microscope and 14 under transmission electron microscope. RESULTS: Immediately after laser irradiation, the dermal melanocytes were destroyed, the melanosomes were degenerated with central vesicle formation within most of them, and intradermal round vacuoles appeared. The epidermis remained intact. Three months to 1 year after irradiation, the degenerated melanosomes and cell debris were scavenged mainly by macrophages. Dermal melanocytes gradually decreased. No fibrosis was found. CONCLUSION: Q-switched alexandrite laser can selectively destroy dermal melanocytes of nevus of Ota and treat the disease safely. (+info)
Treatment of 522 patients with Nevus of Ota with Q-switched Alexandrite laser.
OBJECTIVE: To evaluate the clinical response of Nevus of Ota to Q-switched Alexandrite laser, and analyze factors that influence the treatment outcome. METHODS: A total of 522 patients treated with Q-switched Alexandrite laser were included in the study. Single and multiple variate analyses of various factors were performed. RESULTS: Satisfactory result was observed in all patients, none of whom developed scarring. Clinical response was improved with additional treatment sessions. The clinical response of the 20 - 27-week treatment interval group was significantly better than that of the 12 - 19-week interval group, but showed no significant difference as compared with both the 28 - 35 and > or = 36-week interval group. Zygomatic, buccal and frontal areas showed better response than ocular and temporal areas. Treatment session, interval, and fluence were significant factors identified by multivariate analysis. CONCLUSIONS: Q-switched Alexandrite laser is an ideal method for treating Nevus of Ota without injury. The number of treatment sessions is more important than interval or fluence. (+info)
Effect of Q-switched Alexandrite laser irradiation on epidermal melanocytes in treatment of Nevus of Ota.
OBJECTIVE: To investigate injury to epidermal melanocyte by Q-switched Alexandrite laser. METHODS: Multiple biopsies were performed on 5 patients with nevus of Ota from before irradiation to 1 year after irradiation. Fourteen specimens were obtained for light microscopy, and 17 for transmission electron microscopy. RESULTS: Melanosomes in epidermal melanocytes were both smaller in size and fewer in number than those in dermal melanocytes. Immediately after irradiation, focal extracellular vacuoles of the basal layer could be observed under light microscopy. Most epidermal melanocytes underwent mild or moderate injury in the form of vacuolated melanosomes, swollen mitochondria, dilation of endoplasmic reticulum, and expansion of extracellular space, retaining intact cell membranes. Normal structures were restored 5 months to 1 year after irradiation, with no depigmentation or hyperpigmentation as seen by light microscopy. CONCLUSION: Injury of melanosomes in epidermal melanocytes is reversible. (+info)
Comparison of characteristics of acquired bilateral nevus of Ota-like macules and nevus of Ota according to therapeutic outcome.
Both acquired bilateral nevus of Ota-like macules (ABNOM) and nevus of Ota are characterized by the presence of dermal melanocytes. There are no differences in the method of treatment, however, postinflammatory hyperpigmentation (PIH) develops more often in ABNOM than in nevus of Ota following treatment. We investigated the differences in the development of PIH after treatment between ABNOM and nevus of Ota, and the histopathologic differences in the PIH. A total of 82 patients with ABNOM (n=47) and nevus of Ota (n=35) were treated with Q-switched alexandrite laser and followed up 2 weeks and 3 months later. Biopsies were performed on lesional skin before treatment. The distribution and the amount of melanin pigments were visualized with Fontana-Masson stain, and the distribution and the depth of melanocytes were measured by GP-100 (NK1-beteb) stain. Clinically, there was more erythema and PIH in ABNOM than in nevus of Ota. Histopathologically, intradermal melanocytes were clustered in groups and dispersed perivascularly in ABNOM, while melanocytes were scattered evenly throughout the dermis in nevus of Ota. Both groups show that when there is a statistically significant number of melanocytes in the perivascular area, erythema and PIH occur after laser therapy. In conclusion, indirect vessel injury in addition to perivascular clustering melanocytes might be considered the cause of increased PIH after treatment in ABNOM. (+info)
Acquired, bilateral nevus of Ota-like macules (ABNOM) associated with Ota's nevus: case report.
Ota's nevus is mongolian spot-like macular blue-black or gray-brown patchy pigmentation that most commonly occurs in areas innervated by the first and second division of the trigeminal nerve. Acquired, bilateral nevus of Ota-like macules (ABNOM) is located bilaterally on the face, appears later in life, is blue-brown or slate-gray in color. It is not accompanied by macules on the ocular and mucosal membranes. There is also debate as to whether ABNOM is part of the Ota's nevus spectrum. We report an interesting case of ABNOM associated with Ota's nevus. A 36-yr-old Korean women visited our clinic with dark bluish patch on the right cheek and right conjunctiva since birth. She also had mottled brownish macules on both forehead and both lower eyelids that have developed 3 yr ago. Skin biopsy specimens taken from the right cheek and left forehead all showed scattered, bipolar or irregular melanocytes in the dermis. We diagnosed lesion on the right cheek area as Ota's nevus and those on both forehead and both lower eyelids as ABNOM by clinical and histologic findings. This case may support the view that ABNOM is a separate entity from bilateral Ota's nevus. (+info)
The use of lasers and intense pulsed light sources for the treatment of pigmentary lesions.
Lasers and intense pulsed light sources are frequently used for the treatment of pigmented lesions, and the appropriate selection of devices for different lesions is vital to achieving satisfactory clinical outcomes. In dark-skinned patients, the risk of post-inflammatory hyperpigmentation is of particular importance. In general, long-pulse laser and intense pulsed light sources can be effective with a low risk of post-inflammatory hyperpigmentation (PIH) when used for the treatment of lentigines. However, for dermal pigmentation and tattoo, Q-switched lasers are effective, with a lower risk of complications. In the removal of melanocytic nevi, a combined approach with a long-pulse pigmented laser and a Q-switched laser is particularly applicable. (+info)