Preliminary experience of the Q‐switched 1064‐nm neodymium:yttrium aluminum garnet laser in the treatment of Café‐au‐lait macules

Laser treatment for Cafe-au-lait Macules: a systematic review and meta-analysis

Nowadays, laser is the mainstay treatment for cafe-au-lait macules (CALMs), but no systematic review has been published to demonstrate the overall efficacy and it's still controversial which type of laser is optimal. Thus, we conduct the meta-analysis to evaluate the effectiveness and side effects of various types of lasers in treating CALMs. Original articles reporting the efficacy and side effects for CALMs in laser treatment were identified in PubMed, EMBASE, and Web of Science from 1983 to April 11, 2023. Using R software and the 'meta' package, meta-analysis was conducted for clearance and recurrence for evaluation of efficacy. And the occurrence of hypopigmentation and hyperpigmentation rate was pooled for safety evaluation. We used RoB2 and ROBINS-I tools to assess the risks of bias in RCT studies and non-RCT studies, respectively. The Grading of Recommendations, Assessment, Development and Evaluation system was used to assess the quality of the evidence. Nineteen studies involving 991 patients were included, which had a very low to moderate quality of evidence. The pooled 75% clearance rate was 43.3% (95% CI 31.8-54.7%, I² = 96%), 50% clearance rate was 75% (95% CI 62.2-85.9%, I² = 89%) and the recurrence rate was 13% (95% CI 3.2-26.5%, I² = 88%). The pooled hypopigmentation and hyperpigmentation rates were 1.2% (95% CI 0.3-2.1%, I² = 0%) and 1.2% (95% CI 0.3-2%, I² = 0%), respectively. Subgroup analysis revealed that QS-1064-nm Nd:YAG laser treatment not only achieved more than 75% clearance rate in 50.9% of patients (95% CI 26.9-74.4%, I² = 90%) but also resulted in the lowest hypopigmentation and hyperpigmentation rate of 0.5% (95% CI 0.0-2.5%, I² = 26%) and 0.4% (95% CI 0.0-2.5%, I² = 0%). To draw a conclusion, the laser treatment could reach an overall clearance rate of 50% for 75% of the patients with CALMs, for 43.3% of the patients, the clearance rate could reach 75%. When looking at different wavelength subgroups, QS-1064-nm Nd:YAG laser exhibited the best treatment capability. Laser of all the wavelength subgroups presented acceptable safety regarding of the low occurrence of side effects, namely, hypopigmentation and hyperpigmentation.

Comparison of the safety and efficacy of low fluence Q-switched 1064-nm and conventional Q-Switched 755-nm lasers in the treatment of café-au-lait macules: A prospective self-controlled trial

BACKGROUND

Conventional high fluence Q-switched (HFQS) Alexandrite 755-nm are widely used in clinical café-au-lait macules (CALMs) treatment. There have been recent concerns regarding the efficacy and safety of low fluence Q-switched (LFQS) Nd: YAG 1064-nm lasers.

OBJECTIVE

To evaluate the efficacy and safety of the conventional HFQS and LFQS laser in the treatment of CALMs.

METHODS

Within 3 months, 20 patients underwent prospective self-controlled split-lesion treatments with HFQS once or twice depending on the recovery rate, and with LFQS six times biweekly. Then the more effective laser was selected for continued treatments. Efficacy outcomes were evaluated by a visual analog scale (VAS) biweekly during the comparative trail. Recovery process, side effects and recurrence were recorded during the trial and follow-up visit. Patient and physician preferences for laser selection were also recorded.

RESULTS

The average VAS scores of areas treated with HFQS and LFQS were 2.92 ± 0.86 and 2.93 ± 1.13, respectively (p > 0.05). The most significant efficacy change of LFQS was after the fourth laser treatment (VAS score: 1.82-2.37, p < 0.001). 11 lesions treated with LFQS and 7 with HFQS achieved an optimal treatment response (3.67 ≤ VAS ≤ 4). Three patients relapsed on one side (one on LFQS, two on HFQS) and five on both sides. Adverse effects included temporary hypopigmentation, hyperpigmentation, uneven pigmentation, and mottled hypopigmentation. Doctors thought 80% of patients were suitable for LFQS. 70% of patients preferred LFQS posttreatment.

CONCLUSIONS

The efficacy difference between the LFQS 1064-nm laser and HFQS 755-nm laser in treating CALMs in a 3-month comparative trial was statistically insignificant. LFQS is preferred by doctors and patients and is likely to help more patients achieve treatment efficacy than the HFQS within a short time, with fewer temporary adverse reactions, and a more even pigmentation. But it can cause mottled hypopigmentation. The LFQS had obvious lesion clearance after the fourth treatment.

Comparison of the efficacy and safety between a low-fluence 1064-nm Q-switched neodymium-doped yttrium aluminum garnet laser and a conventional Q-switched 532-nm laser for the treatment of cafe-au-lait macules in 40 Chinese children: a prospective, randomized, parallel-controlled, evaluator-blinded trial

Cafe-au-lait macules (CALMs) affect the appearance of patients and can result in serious psychological problems. Successful treatments without adverse effects remain challenging. We designed a prospective, randomized, controlled, evaluator-blinded trial on 40 pediatric patients to compare the efficacy between a low-fluence 1064-nm Q-switched Nd:YAG laser and a Q-switched Nd:YAG 532-nm laser for the treatment of solitary CALMs in children. We randomly assigned participants into 2 groups. We treated those in the first group with 3 sessions of 532-nm QS laser at 1-month intervals, and those in the second group with 6 sessions of 1064-nm LFQS laser at 2-week intervals. We found no significant differences in treatment efficacy (p = 0.14). The 1064-nm laser group referred significantly less pain than the 532-nm laser group (p = 0.0001). Side effects were detected in 5 patients in the 532-nm laser group. The difference of the side effects was statistically significant (p = 0.04). Two patients in 532-nm laser group were recurred and none in 1064-nm laser group. On a univariate logistic regression analysis, lesions with brown color, small size, and irregular edges were significantly associated with better outcomes (> 50% clearance). Multivariate logistic regression analysis found that brown lesions and lesions with irregular edges had higher odds of getting > 50% clearance (p < 0.05). In conclusion, the 1064-nm LFQS laser produced fewer side effects, less pain, and shorter recovery time than the 532-nm laser. Irregular-bordered, smaller, brown lesions improved better than smooth-bordered, larger, light brown lesions. Moreover, the 1064-nm laser may be a better choice for treating large size CALMs. However, no significant differences were found in terms of the treatment efficacy and recurrence.