Why isn the porphyrin count reduced after cleansing?
There are several potential reasons why the porphyrin count for a particular patient may not be reduced-or worse case, increase, after cleansing his/her skin. First, certain types of paper/tissue that might have been used to dry the face after cleansing could have a high content of lint particles. Lint will actually fluoresce under UV light. Greg Hillebrand, a subject matter expert at P&G on the subject, offers the further explanation that “in some situations, the true porphyrin fluorescence of an initial image could be quenched by something that the subject had on his/her unclean face, and then after removal of this interfering quenching agent, a higher level of fluorescence could be observed. Finally, the simple cleansing of the skin with a normal everyday facial cleanser is probably not going to change the true number of pores that show porphyrin fluorescence. It has been reported that washing with a cleanser containing benzoyl peroxide will, over time, reduce the number of pores.
