Q‐switched frequency‐doubled Nd:YAG (532 nm) laser versus trichloroacetic acid 35% peeling in the treatment of dorsal hand solar lentigo: An assessor‐blind split‐hand randomized controlled trial

Abstract

Background Solar lentigo (SL) is a benign hyperpigmented spot occurring due to ultraviolet exposure, most commonly in the elderly. We aimed to compare the safety and efficacy of trichloroacetic acid (TCA) peeling with Q‐switched laser in the treatment of SLs. Methods This assessor‐blind split‐hand randomized controlled trial included 45 patients with symmetric SLs on the back of their hands referred to the dermatology clinics from March 1 to June 24, 2021. TCA 35% was applied to the back of one hand, and the contralateral hand received Q‐switched laser. The interventions were repeated for a total of three sessions 4 weeks apart. Eight weeks after the last treatment session, lesion lightening was graded from 1 to 4. Patient satisfaction with treatment was assessed using a visual analogue scale (VAS). Adverse events were also noted. Results Of the 45 patients included in the current study with a mean age of 52.71 ± 9.73 years, 11 (24.4%) were male. The Fitzpatrick skin type was II in 11 patients (24.4%), III in 23 (51.1%), and IV in 11 (24.4%). Lesion lightening and patient satisfaction were both significantly better with Q‐switched laser compared to TCA peeling (standardized mean difference [SMD] = −1.25, 95% confidence interval [CI] ‐1.69; −0.79, p < 0.001 and SMD = ‐1.12, 95% CI ‐1.56; −0.67, p < 0.001, respectively). Overall, post‐inflammatory hyperpigmentation (PIH) occurred in one patient in the laser group and for in the TCA group. Also, erythema and pruritus were observed in all patients of both groups after intervention which were treated with topical repair cream. Conclusions Q‐switched laser was superior to TCA peeling for the treatment of SLs in terms of lesion lightening and patient satisfaction with a large effect.

A 15% Trichloroacetic Acid + 3% Glycolic Acid Chemical Peel Series Improves Appearance of Hand Lentigines: An Evaluator-Blinded, Split-Hand Prospective Trial

“…[14][15][16] Furthermore, chromophore-specific devices targeting pigment, such as laser or other energy-based devices, can also be effective. 12,[23][24][25][26] Focal treatment of lentigines using TCA has previously been reported. Chun and colleagues 16 treated 49 patients with solar lentigines using 50% to 65% TCA, showing a good clinical response in 42 patients (82%) .…”

“…Overall, patient satisfaction and lesion lightening was significantly better in the QS Nd:YAG group compared with the TCA 35% group. 12 Other studies have suggested using a combination of IPL or QS Alexandrite lasers and chemical peels for optimal results in addressing hand pigmentation. [33][34][35] Limitations to this study included unblinded subject ratings, small sample size (n 5 18), lack of higher Fitzpatrick skin types in the study population, and lack of sex and racial/ethnic diversity.…”

“…[7][8][9][10] Lentigines can be effectively treated with chemical peels, which resurface the superficial portion of the epidermis to remove undesirable pigment, thereby addressing extrinsic signs of photoaging. [11][12][13][14][15][16] Specifically, trichloroacetic acid (TCA) ,35% peels have been used for decades for superficial chemical peeling because of its efficacy, safety profile, and ability to correlate peel depth with color of surface frost. 17,18 The white frost caused by TCA peels is due to keratocoagulation or protein denaturation of membrane proteins.…”

“… 20 Previous studies comparing TCA 35% with Q-switched lasers have shown efficacy of both modalities in treated lentigines in nonfacial areas. 12 To minimize side effects, using lower concentrations of TCA is advisable in nonfacial areas. Therefore, this study prospectively investigates the efficacy of a 15% trichloroacetic acid (TCA) + 3% glycolic acid (GA) chemical peel for treatment of lentigines on the hands.…”

In Vitro, In Vivo, and In Silico Analyses of Molecular Anti-Pigmentation Mechanisms of Selected Thai Rejuvenating Remedy and Bioactive Metabolites

“…These changes lead to skin problems, for instance, one of the most common problems is solar lentigo (a hyperpigmented spot on the skin) [ 8 , 9 ]. Research studies have found that aging and prolonged UV exposure are common risk factors [ 8 , 10 ]. These factors cause pigment overproduction, known as hyperpigmentation.…”