What is the recommended laser management approach for post-inflammatory hyperpigmentation (PIH)?

Laser Management for Post-Inflammatory Hyperpigmentation

Laser therapy should be considered a second-line treatment for post-inflammatory hyperpigmentation (PIH), particularly in patients with darker skin tones, as it carries risks of worsening hyperpigmentation while offering only partial improvement in most cases. 1

Efficacy of Laser Treatments for PIH

• The 1,927 nm non-ablative fractional laser has shown promising results for PIH in darker skin types (Fitzpatrick IV-VI), with a mean improvement of 43.24% and no reported side effects in treated patients. 2

• Laser and energy-based devices achieve complete resolution in only 18.1% of patients, while partial response occurs in 61.2% of cases. Notably, 2.6% of patients experience worsening of PIH after laser treatment. 3

• The Q-switched Nd:YAG laser has demonstrated the most promising results among studied laser devices for PIH treatment. 4

Treatment Algorithm for PIH Management

First-Line Approach

• Topical agents should be used as first-line therapy before considering laser treatment, as they offer a safer profile despite showing complete response in only 5.4% of patients. 3, 1

When to Consider Laser Therapy

• Consider laser therapy for PIH cases that are resistant to topical treatments. 1
• Laser therapy may be particularly beneficial for treating residual flat areas and superficial vascular components of PIH. 5

Laser Selection Based on Skin Type

• For patients with darker skin tones (Fitzpatrick III-VI):
  • Neodymium:YAG lasers and fractional photothermolysis systems are preferred due to lower risk of complications. 1
  • Low energy, low density 1,927 nm non-ablative fractional laser has demonstrated safety and efficacy with 43.24% mean improvement. 2

Risks and Complications

• Complications of laser treatment include atrophic scarring and hypopigmentation, particularly in individuals with darker complexion. 5

• Laser therapy can induce ulceration in some cases, though this is relatively rare. 5

• In 2.6% of patients treated with laser and energy-based devices, PIH may worsen rather than improve. 3

• The risk of post-laser PIH is higher in patients with darker skin tones, making careful patient selection critical. 1

Practical Considerations

• Dynamic cooling delivered to the skin before the laser pulse has made treatment safer and less painful. 5

• Combination therapies show the highest rate of partial response (84.9%) compared to laser therapy alone (61.2%), suggesting a multimodal approach may be more effective. 3

• Current models of pulsed dye laser use a wavelength of 595 nm and larger spot sizes (up to 10 mm) with higher fluences, allowing deeper penetration. 5

• Longer pulse durations facilitate the treatment of larger vessels in vascular components of PIH. 5

Special Considerations for Darker Skin Types

• Patients with Fitzpatrick skin types IV-VI require more cautious approach due to increased risk of post-treatment hyperpigmentation. 2, 1

• In a systematic review of 1,356 patients with skin of color, laser therapy offered complete resolution in 26% of cases, but also carried risk of PIH exacerbation. 6

• The ethnic distribution of PIH in skin of color shows 70% Black, 27% Asian, and 3% Latin patients, with most cases (83%) affecting the face. 6