Hair growth cycle affects hair follicle destruction by ruby laser pulses

Tai Yuan David Lin, Woraphong Manuskiatti, Christine C. Dierickx, William A. Farinelli, Marnie E. Fisher, Thomas Flotte, Howard P. Baden, R. Rox Anderson

Research output: Contribution to journalArticlepeer-review

80 Scopus citations


It has been shown that normal mode ruby laser pulses (694 nm) are effective in selectively destroying brown or black pigmented hair follicles in adult Caucasians. This study investigated how the various stages of the hair follicle growth cycle influence follicle destruction by ruby laser treatment, using a model of predictable synchronous hair growth cycles in the infantile and adolescent mice. A range of ruby laser pulse fluences was delivered during different stages of the hair growth cycle, followed by histologic and gross observations of the injury and regrowth of hair. Actively growing and pigmented anagen stage hair follicles were sensitive to hair removal by normal mode ruby laser exposure, whereas catagen and telogen stage hair follicles were resistant to laser irradiation. Selective thermal injury to follicles was observed histologically, and hair regrowth was fluence dependent. In animals exposed during anagen, intermediate fluences induced nonscarring alopecia, whereas high fluences induced scarring alopecia. The findings of this study suggest treatment strategies for optimal laser hair removal.

Original languageEnglish (US)
Pages (from-to)107-113
Number of pages7
JournalJournal of Investigative Dermatology
Issue number1
StatePublished - 1998


  • C57BL6
  • Hair removal
  • Selective thermolysis

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Dermatology
  • Cell Biology


Dive into the research topics of 'Hair growth cycle affects hair follicle destruction by ruby laser pulses'. Together they form a unique fingerprint.

Cite this