A pilot methodology study for the photographic assessment of post-inflammatory hyperpigmentation in patients treated with tretinoin

J Eur Acad Dermatol Venereol. 2011 Apr;25(4):398-402. doi: 10.1111/j.1468-3083.2010.03798.x.


Background: Post-inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour.

Aims: A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual-controlled methodology study that consisted of a photographic assessment protocol with facial mapping.

Materials and methods: The study was based on a secondary analysis of a phase 4, community-based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III-V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation.

Results: Despite the small number of subjects evaluated (n=25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ=0.84).

Conclusion: Further study with a larger population is recommended to validate the accuracy of this method.

Publication types

  • Clinical Trial, Phase IV
  • Controlled Clinical Trial

MeSH terms

  • Acne Vulgaris / complications
  • Acne Vulgaris / drug therapy*
  • Dermatitis / complications*
  • Dermatologic Agents / adverse effects
  • Dermatologic Agents / therapeutic use*
  • Humans
  • Photography
  • Pigmentation Disorders / chemically induced
  • Pigmentation Disorders / complications
  • Pigmentation Disorders / pathology*
  • Pilot Projects
  • Tretinoin / adverse effects
  • Tretinoin / therapeutic use*


  • Dermatologic Agents
  • Tretinoin