Development of a Clinical Photographic Atlas for Skin Aging Based on the Characterization of Facial Dermal Collagen Using LC-OCT Technology

Single-center, single visit study in healthy female subjects, aged 20 to 75 years inclusive meeting specific inclusion/exclusion criteria. The study is to develop a clinical photographic atlas to assess skin aging by studying the relationship between age, sun exposure and quantity of collagen measured non-invasively (LC-OCT). No product will be tested during the study.

• LC-OCT acquisitions on the forehead (Diagnostic test): During the study visit, the investigator will for each subjects in Group 1: \- Perform standardized photographs using the ColorFace Group 2: \- Perform standardized photographs using the ColorFace Group 3: \- Perform standardized photographs using the ColorFace Group 4: * Perform standardized photographs using the ColorFace * Perform LC-OCT acquisitions on the forehead Group 5: * Perform standardized photographs using the ColorFace®; * Perform LC-OCT acquisitions on the forehead
• Perform standardized photographs using ColorFace (Device): Photographs
• LC-OCT acquisitions on forehead (Device): Image acquisition
• Perform photo-shooting using smartphones (Device): photo from back and front camera pictures and selfie

Primary outcomes

• Non-invasive tissue imaging: 3D imaging through Line-field Confocal Optical Coherence Tomography technology (LC-OCT) acquisitions [Day 1]: Line-field Confocal Optical Coherence Tomography technology (LC-OCT) provides a unique 3D imaging modality, allowing the user to switch from a histology-like vertical mode to confocal-like horizontal mode and to record a 3D stack of tissue volumes in situ. With this technique skin can be imaged in vivo in its native state without further preparation. The superficial dermis can be clearly imaged using a live vertical, live horizontal and 3D mode. This assessment will be performed on the face (forehead) with the LC-OCT deepLive™ (DAMAE). This non invasive image will helps to characterize and quantify new metrics of skin aging linked to the dermal fibers network (collagen and elastin) such as caracterisation of the density and length of dermis fibers during aging.

Secondary outcomes

• Standardized photographs of the face (front and 45° left and right sides) [Day 1]: Standardized photographs of the face (front and 45° left and right sides) will be performed using the ColorFace (Newtone Technologies, Lyon, France). The ColorFace® has multiple lighting modes and can acquire up to 5 images in one setting from a user-definable shooting template without technician intervention. Subjects will be photographed using the following modalities: * Cross-polarized (polarizing filter angle: 90 degrees, no specular gloss on the skin surface and observation of color variations) * Standard 60 (polarizing filter angle: 60 degrees, observation of skin relief such as wrinkles) * No filter * Parallel-Polarized (polarizing filter angle: 0 degrees, observation of skin relief such as pores) * UV (observation of the pigmentation not visible to the naked eye). All the digital photographs will be identified by the protocol number, the SIN, the side photographed, the type of light used and anomyzed. They serve for illustration purposes of visible signs during skin aging .
• Photo shooting [Day 1]: Photo shooting (Back and Front camera pictures) will be performed using an iPhone 15. Back camera pictures will be taken by a trained personnel and the front camera picture will be taken by the subject himself after a brief training by the study personnel. These photos will serve for grading facial aging: Comparing the clinical assessments made by three dermatologists with those obtained by an AI-based scoring system that analyses selfie pictures.
• Questionnaire [Day 1]: Subjects will be asked to complete a self-assessment questionnaire about their lifestyle habits in order to assess the link between lifestyle habits and aging.

Sex: Female, ages: 20 Years to 75 Years, accepts healthy volunteers

Inclusion Criteria:

* Subject having signed an Informed Consent Form (ICF) before any trial related activity is carried out;
* Healthy female subject aged 20 to 75 years inclusive at the time of signing the ICF;
* Subject with a phototype I to III on Fitzpatrick's scale;
* Subject who is willing to follow the study procedures and to complete the study course;
* Subject registered with Social Security in agreement with French law on study research.

Exclusion Criteria:

* Male subject;
* Female subject who is pregnant or who is breast feeding;
* Subject with current participation in any other interventional clinical study, based on interview of the subject;
* Subject with facial dermatitis, rosacea, acne, eczema, psoriasis, skin rashes, open lesions, vitiligo or viral conditions such as herpes labialis;
* Subject who has collagen vascular disease, a significant systemic disease, immunological problems or inflammatory skin conditions on the face;
* Subject who has had a face lift;
* Subject has had a non-ablative and/or ablative laser procedure on the face in the past 3 months;
* Subject with a history of botulinum toxin or mesotherapy injections on the face within the last 6 months, or absorbable fillers injections (such as hyaluronic acid or autologous fat…) in the last 12 months or injectable implants (semi-permanent fillers) within the last 24 months;
* Subject having done a moderate to deep peeling or non-invasive rejuvenation techniques such as radiofrequency, ultrasound and lasers in the last 6 months;
* Subject having applied any cosmetic product (care cream, lotion, makeup) except usual cleansing products or any drug to her face on the day of the visit;
* Subject who has been deprived of their freedom by administrative or legal decision, or who is under care of a guardian or legal guardianship, or subject hospitalized in a medical or social establishment for any reason.

• Catherine QUEILLE-ROUSSEL, MD, Principal investigator, CPCAD, Hôpital l'Archet 2