Hypertrophic scars are difficult to improve and remain a therapeutic challenge. Several
lasers and light sources have been evaluated in the past decades and have been shown to improve
hypertrophic scars. However, a systematic review is not available. To assess current evidence of efficacy of all
laser and intense pulsed
light therapies used in the treatment of
hypertrophic scars, we performed a systematic review searching electronic databases MEDLINE, EMBASE and CENTRAL. The quality of the controlled clinical trials was evaluated according to the Cochrane Collaboration's tool for assessing risk of bias. Thirteen articles involving seven different
lasers met the inclusion criteria. Most evidence was found for the
pulsed dye laser (PDL) 585 nm (eight studies), followed by the PDL 595 nm (two studies), whereas limited evidence (one trial per
laser) was available for the fractional nonablative
laser 1540 nm, CO₂
laser 10,600 nm,
low-level laser therapy,
Nd:YAG laser 532 nm and
Erbium:YAG laser 2940 nm. Treatment recommendations should be formulated with caution as current evidence is insufficient for comparing the efficacy of different
laser therapies. The PDL 585 nm showed a low efficacy for the treatment of
hypertrophic scars. With moderate efficacy, the PDL 595 nm is promising, although more research is necessary. Little evidence was found for the efficacy of other
lasers. Future research, with a low risk of bias, well-defined
scar characteristics, validated outcome measures, standardized measurement methods, follow-up periods of at least 6 months and well-defined
laser settings, is needed.