Tolerance and Performance of Cyto-selective Difluoroethane-based Cryotherapy in the Treatment of Brown Spots

CS5_1 study aim to evaluate the tolerance and to adjust the mode of administration of 4 different conditions of cryotherapy treatments applied on the brown spots of the face and hand with 3 prototypes.Each treatment corresponds to a combination of a specific sequence of a cryogenic spray and of a frequency of application.The study will evaluate 3 prototypes :Prototype 1 : from (815-v1 001) to (815-v1 100)Prototype 2 : from (815-v1 101) to (815-v1 150)Prototype 3 : from (815-v1 151) to (815-v1 200)

Inclusion Criteria:Female or male.Ages 30 to 75.Phototypes I to IV (according with Fitzpatrick scale).Featuring brown spots (solar lentigos, senile lentigo) on the face and hands ≥ 3 and ≤ 6 mm in diameter (at least 4 spots per subject for phototypes II and III and no specific requirements re accurate number of spots for phototypes I and IV).).Agreeing not to be exposed to the sun (or artificial UV) during the study.Informed, having undergone a general clinical examination attesting to his/her ability to participate in the study.Having given written consent for their participation in the study.No suspicion of carcinoma after investigation by a dermatologist.Exclusion Criteria:Having performed cosmetic treatments (exfoliants, scrubs or self-tanners, manicures, facials, UV ...) in the month before the start of the study, at the level of the face and the hands.Having applied a depraving product in the month prior to the start of the study, at the level of the face and the hands.Having performed cosmetic treatments in a dermatologist (laser, Intense Pulsed Light (IPL) , peeling, creams, cryotherapy ...), at the level of the face and the hands in the last 6 months.With dermatosis, autoimmune disease, systemic, chronic or acute disease, or any other pathology that may interfere with treatment or influence the results of the study (people with diabetes or circulatory problems, allergic to cold, Raynaud's syndrome...).Receiving treatment by general or local (dermo corticoids, corticosteroids, diuretics ...) likely to interfere with the evaluation of the parameter studied.Participating in another study or being excluded from a previous study.Unable to follow the requirements of the protocol.Vulnerable: whose ability or freedom to give or refuse consent is limited.Major protected by law (tutorship, curatorship, safeguarding justice...).People unable to read and write Georgian language.Unable to be contacted urgently over the phone.For female subjects:Pregnant woman (or wishing to be pregnant during study) or while breastfeeding.A woman who does not have a contraceptive method.