Clinical use of the Q-switched Nd:YAG laser for the treatment of acquired bilateral nevus of Ota-like macules (ABNOMs) in Koreans

A retrospective study of 1064-nm Q-switched Nd:YAG laser therapy for acquired bilateral nevus of Ota-like macules

BACKGROUND

The therapeutic efficacy of laser treatments for acquired bilateral nevus of Ota-like macules (ABNOM) varies among studies, and few studies have evaluated the factors affecting therapeutic effects.

AIMS

To evaluate the efficacy and safety of 1064-nm Q-switched Nd:YAG laser (QSNYL) therapy for ABNOM and to identify the factors influencing the outcome.

METHODS

A total of 110 patients with ABNOM were retrospectively evaluated and received two-to-nine treatment sessions. The effects of different factors on the therapeutic effect were analyzed on the basis of the number of treatments, age at first treatment, skin type, lesion color, affected area, number of lesion sites, and presence of concomitant melasma.

RESULTS

The curative effect was positively correlated with the treatment time and negatively correlated with the increasing age at first treatment (p < 0.05). The curative effect was better in patients with skin type III than those with type IV ( p < 0.05) and in patients with a lesion area of less than 10 cm2 than those with a larger affected area (p < 0.05). Additionally, the treatment effect was poorer in patients with concomitant melasma (p < 0.05). The treatment effect was not significantly correlated with the lesion color or number of affected sites (p > 0.05). Eleven patients (10%) developed postinflammatory hyperpigmentation (PIH).

CONCLUSIONS

Early and repeated QSNYL therapy achieved satisfactory results for ABNOM. The risk of PIH after laser treatment is highest among patients with older age, darker lesion color, and darker skin color. For patients with ABNOM with concurrent melasma, low-energy laser therapy is recommended to reduce the risk of melasma aggravation.

Efficacy and safety of 755 nm Q-switched Alexandrite Laser for Hori's nevus: a retrospective analysis of 482 Chinese women

To evaluate the efficacy and safety of 755 nm Q-Switched alexandrite laser for Hori's nevus in a large cohort of Chinese women. We retrospectively analyzed the efficacy and safety of 755 nm Q-Switched alexandrite laser for Hori's nevus. Reduction in pigment was evaluated using a 4-score method. A total of 482 patients, aged 16 to 52 years, were included in this analysis. Patients were treated with 755 nm Q-Switched alexandrite laser at fluence levels of 5-8 J/cm² for 2-4 treatment sessions. Following the treatments, 53% of patients showed over 75% reductions in pigment while 50-75% reductions in pigment were observed in 28% of patients. The rest displayed less than 50% improvements. Efficacy was positively correlated with the number of treatment sessions (p < 0.0001). Adverse reactions were temporary, mild erythema, and edema. A small portion of patients (15%) had hyperpigmentation, which disappeared within 2-6 months. 755 nm Q-Switched alexandrite laser is safe and has moderate benefits for Hori's nevus. Because its efficacy is positively correlated with the number of treatment sessions, increase in treatment sessions possibly could achieve a better outcome.

Clinical Evaluation of Safety and Efficacy of a 670-nm Picosecond Laser for Treatment of Benign Pigmented Lesions in Asians

BACKGROUND

Picosecond lasers are increasingly being investigated in treating pigmentation disorders because they may provide better treatment efficacy and comfort compared with nanosecond lasers.

OBJECTIVE

This study aims to evaluate the efficacy and side effect of a novel 670-nm picosecond laser in the removal of benign pigmented lesions (BPLs) in individuals with Fitzpatrick skin types (FST) III and IV.

MATERIALS AND METHODS

Fifteen subjects with solar lentigines and 7 subjects with ABNOMs received a single treatment with a 670-nm picosecond laser. Blinded physicians assessed the pigment clearance using a 5-category grading system scale. All subjects were evaluated at 1 month, 3 month, and 6 month after a single treatment. Adverse events were recorded at every follow-up visit.

RESULTS

All subjects with lentigines had complete clearance (95%-100%) of lesions during 3-month follow-up after a single treatment session of 670-nm picosecond laser, whereas 75% of the subjects with ABNOMs noted fair lightning (25%-49%) of lesions. Mild hypopigmentation and hyperpigmentation were observed in 9% and 14% of the subjects, respectively, which resolved within 3 months after the treatment.

CONCLUSION

The novel 670-nm picosecond laser is a safe and effective treatment for BPLs in subjects with FST III and IV with low rates of transient adverse effects.

Therapeutic options for management of Hori's nevus: A systematic review

Hori's nevus is a pigmentation disorder reported mainly in middle-aged Asian women. There is no systematic review addressing its pharmacotherapy. The population for our systematic review was patients with a clinical/histological diagnosis of Hori's nevus (both sex, any age group). We screened five literature databases using relevant keywords. All RCTs, observational studies and case series mentioning at least one intervention and outcome of that intervention were included. Nineteen studies were included in the final systematic review from total 680 identified nonduplicate records. Different forms of laser (alexandrite laser [QSAL and PSAL], Nd:YAG laser [QSNYL high fluence, low fluence, 532 followed by 1064 nm], Er: YAG and Nd:YAG combination, ruby laser [QSRL], CO₂ laser followed by QSRL) and dermabrasion were found to be useful in treatment of Hori' nevus. Among alexandrite lasers, PSAL is more efficacious and safe than QSAL. In case of high fluence QSNYL, hyperpigmentation rate is quite high while low fluence QSNYL requires more number of treatment sessions. The combined 1064 nm + 532 nm protocol is better in terms of efficacy and safety. Er:YAG + Nd:YAG combination have similar efficacy and added advantage of synergistic action and no adverse event.

Induction of melasma by 1064-nm Q-switched neodymium:yttrium-aluminum-garnet laser therapy for acquired bilateral nevus of Ota-like macules (Hori nevus): A study on related factors in the Chinese population

Laser treatment has emerged as a common treatment modality for acquired bilateral nevus of Ota-like macules (ABNOM). To identify the ratio of melasma induction and exacerbation before and after laser therapy for ABNOM and to observe the risk factors related to the induction and exacerbation of melasma by laser therapy, we analyzed related factors of 1268 adult Chinese patients who underwent 1064-nm Q-switched neodymium:yttrium-aluminum-garnet (Nd:YAG) laser (QNYL) treatment using case series and case-control studies. Overall, 24.0% of the ABNOM patients had mixed melasma. Among the ABNOM patients without melasma, after laser therapy the development of melasma was more frequently noted in patients older than 35 years (P < 0.0001), as well in patients whose ABNOM was less than 10 cm(2) (P = 0.027), ABNOM were light (similar to yellow-brown) in color (P = 0.021) and skin types were closer to type IV (P < 0.0001). New melasma lesions also appeared most frequently in the zygomatic region (P < 0.0001). Among the ABNOM patients with melasma, 89.5% experienced worsening of their melasma, irrespective of their related factors above. We concluded that the risk of inducing melasma is great after 1064-nm QNYL treatment in ABNOM patients, and particularly in the patients with both ABNOM and melasma. ABNOM patients should be treated as early as possible and before the age of 35 years.

Exogenous ochronosis - successful outcome after treatment with Q-switched Nd:YAG laser

BACKGROUND

Exogenous ochronosis (EO), a disfiguring cutaneous complication of topical hydroquinone use, is difficult to treat. There are few reports of successful outcomes following treatment with different modalities.

OBJECTIVE

We assessed the results of treatment of EO with the Q-switched Nd:YAG laser.

MATERIAL AND METHODS

Patients with histologically-confirmed EO were treated with the Q-switched Nd:YAG laser.

RESULTS AND CONCLUSION

Q-switched Nd:YAG laser treatment appears to be effective in reducing the dyschromia of EO.

Q-Switched Nd:YAG Laser Therapy of Acquired Bilateral Nevus of Ota-like Macules

BACKGROUND

Acquired bilateral nevus of Ota-like macules (ABNOM) is a dermal pigmented lesion common in individuals of Oriental origin. The Q-switched Nd:YAG laser (QSNYL) has been used successfully to treat a variety of benign, dermal, pigmented lesions, including nevus of Ota lesions. The similarity between ABNOM and nevus of Ota suggested that QSNYL may also be effective in the former.

OBJECTIVE

To determine the efficacy and side-effect profiles of QSNYL treatment of ABNOM in Korean patients.

METHODS

Of 42 Korean patients with ABNOM, 29 were treated with QSNYL (1,064 nm, 3 mm spot size, fluence 8~9.5 J/cm(2)), for up to 10 sessions each. Clinical photographs were taken before and after treatment. Lesion clearance was graded and complications such as hyperpigmentation, scarring, hypopigmentation, and erythema were assessed.

RESULTS

Of the 29 treated patients, 19 (66%) showed excellent or good results. Of the patients who were treated more than 3 times, 76% showed good to excellent results. Two patients experienced post-laser hyperpigmentation (PLH), which persisted for more than one month, but no patient experienced persistent erythema or hypertrophic scarring.

CONCLUSION

QSNYL is safe and effective in the treatment of ABNOM in Korean patients. Short-interval repetitive treatment is especially useful in improving therapeutic results and reducing PLH.