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Photoadaptation of vitiliginous skin to targeted ultraviolet B phototherapy
Jennifer Rivard1, Camile Hexsel, Michael Owen
1Department of Dermatology, Henry Ford Hospital, Detroit, MI 48202, USA.
Background:
Increasing doses of ultraviolet (UV) radiation are tolerated in patients with vitiligo, due to photoadaptation. In this pilot study, five patients with Fitzpatrick skin phototypes IV-VI with vitiligo received six treatments of targeted UVB phototherapy over a 3-week period.
Methods:
To investigate photoadaptation, minimal erythema dose (MED) testing was conducted on treated and untreated vitiliginous and normal skin at baseline and after three and six treatments. One patient had unattainable MED values, and was hence excluded.
Results:
Percent change in MED from before to after all treatments in vitiliginous skin ranged from 0% to 128%, with a mean of 48.8%.
Conclusion:
The pilot phase of this study suggests possible photoadaptation of vitiliginous skin of some patients to targeted UVB phototherapy.
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