Excimer Light Treatment for Idiopathic Guttate Hypomelanosis: A Pilot Study

Methods: This pilot study will consist of 10 adult subjects with symmetric IGH on the lower legs. After enrollment, 5 lesions of IGH on each leg will be selected by either Dr. Jennifer Gordon or Dr. Ammar Ahmed and marked. Subjects will be randomized to which extremity (right or left) will be treated. Treatments with the Xtrac Excimer laser (wavelength of 308nm) will be performed twice weekly for 12 weeks using the typical vitiligo protocol (see Appendix C). Photographs of both extremities will be taken prior to initial treatment and then every 4 weeks. The photographs will be analyzed by two separate, blinded dermatologists and rated on improvement from baseline using the following scale: 1= worsening of IGH; 2= no improvement (IGH remained stable); 3= mild improvement of IGH (some repigmentation on \<50% IGH); 4= moderate improvement (some repigmentation on \>50% or full repigmentation on \<75% IGH); 5= full repigmentation on \>75% IGH (see Appendix A). Subjects will also be asked to complete this survey subjectively every 4 weeks. Internal control will be represented by the marked lesions on the non-treated extremity of each patient. Control versus treatment groups will be statistically compared; however, due to the limited number of patient in this pilot study, a descriptive trend analysis will likely be completed. Subjects will be compensated $10 per visit (totaling $250). If a subject withdraws early from the study, they will be compensated for every completed visit. The 25th visit will consist of final photographs and surveys, and will not include treatment. Statistical Analysis: The main outcomes to be collected are the improvement of IGH from baseline at weeks 4, 8 and 12 by the blinded dermatologists and by the subjects. Subjects will be stratified by Fitzpatrick skin type for analysis as well.