Inclusion Criteria:
* Subject over 18 years old presenting with ≥ 8 typical actinic keratoses (AK), clinically visible or palpable, grade I or II, with at least 4 AK per hemiscalp,
* Participants who, in the investigator's judgment, are in good general condition (ECOG ≤ 2),
* The AK must be distributed in 2 non-overlapping areas, and of similar grades,
* Patient capable of understanding and adhering to the study visit schedule and other protocol requirements,
* Patient capable of understanding and voluntarily signing informed consent,
* Patient covered by social insurance,
* Patient willing to comply with all study procedures and duration,
* Women of childbearing potential must:
Have a negative pregnancy test at screening and during the treatment period,
Use an effective contraceptive method throughout the study participation. Menopausal women (absence of menstruation for at least one year without other medical cause) or surgically sterile women (tubal ligation, hysterectomy, or bilateral oophorectomy) may be enrolled.
Exclusion Criteria:
* Clinically atypical and/or rapidly evolving actinic keratoses (AK) in the treatment area, and grade 3 AK according to Olsen classification,
* A defined treatment area that would be:
1. Located somewhere other than the scalp and/or forehead,
2. Within 5 cm of a wound that is not fully healed or a lesion suspicious for carcinoma,
* Prior treatment with tirbanibulin,
* Treatment with 5-fluorouracil (5-FU), imiquimod, ingenol mebutate, diclofenac, photodynamic therapy, or other treatments for actinic keratoses in the treatment area or within 2 cm around this area within 6 weeks prior to the screening visit,
* Use of the following therapies within 2 weeks prior to the screening visit:
1. Therapeutic or cosmetic procedures (e.g., liquid nitrogen application, surgical excision, dermabrasion, medium or deep chemical peeling, laser resurfacing) in the treatment area or within 2 cm around the selected treatment area,
2. Therapeutic products containing acids (e.g., salicylic acid, fruit acids), topical retinoids, or light peels in the treatment area or within 2 cm around the selected treatment area,
* Allergy to tirbanibulin or any of its components.
* Any condition causing a risk of poor compliance,
* Administrative reasons: inability to receive informed information, inability to participate in the entire study, lack of social security coverage, refusal to sign the consent form,
* Women of childbearing potential who refuse to use an effective contraceptive method,
* Pregnant women, women planning to become pregnant, and breastfeeding women,
* Persons deprived of liberty by judicial or administrative decision.
