According to international consensus, information on the level of skin oxygenation is necessary for the diagnostic management of chronic wounds. The measurement of transcutaneous partial oxygen pressure (or TcPO2, according to the acronym) is measurable with a medical device that uses a Clark electrode. Since the medical device in question is expensive and the measurement time-consuming (approximately 45 minutes per patient), the TcPO2 is only rarely accessible (in hospital medicine as in nursing homes) and is therefore not predominant in the clinical decision. The clinical decision is currently mainly based on the result of the ankle blood pressure measurement, which is readily available.

The main objective is to study, from the same skin surfaces (same localization of skin sites and same dimensions of each surface in cm²), in patients with cutaneous vascular disorders or chronic wounds, the relationship between (i) the transcutaneous oxygen saturation values (expressed as a percentage) by the innovative non-contact optical imaging device under study (IPAM, method to be validated) and (ii) the transcutaneous partial oxygen pressure values (TcPO2) (expressed in millimeters of mercury, mmHg) measured by the reference medical device (Périflux6000, gold standard).

The InnovaTICs Dépendance project, funded by the Grand Region Is, aims to develop a medical device meeting the need to measure quickly and non-invasively the skin oxygen saturation. To do this, a device medical was developed by CRAN (Joint Research Unit of the University of Lorraine and CNRS); its industrial transfer was entrusted to the company SD Innovation to produce the VRPC device for "video-reconstruction of chronic wounds". The VRPC medical device makes it possible to measure skin oxygen saturation by an optical (atraumatic) and non-contact (non-invasive) method, more quickly than the current method proposes. The capacity of the VRPC device to measure in vivo variations in skin oxygen saturation was confirmed by carrying out measurements on healthy volunteers. The measured values made it possible to show that the VRPC device was able to detect the difference in skin oxygen saturation between the skin covering a "healthy" finger and the skin covering the same finger but after a tourniquet had been placed at the base of the first phalanx of the finger (data not published).

Inclusion Criteria:

• Major,

• Having signed the informed consent to participate in the clinical study

• Compulsory affiliation to a social security scheme

• Presenting at least one of the following two criteria:

  • Presence of a PAD at the stage of Chronic Critical Ischemia (CHF) of stage III or IV according to the classification of Leriche and Fontaine,
  • Presence of one (or more) chronic wound (s) of the lower limbs of the pressure sore or ulcer type.

Exclusion Criteria:

• Person referred to in Articles L. 1121-5, L1121-6, L. 1121-7 and L1121-8 of the Public Health Code.
• Pregnant woman, parturient or nursing mother
• Minor (non-emancipated)
• Adult person subject to a legal protection measure (guardianship, curatorship, safeguard of justice)
• Person of full age unable to express consent
• Persons deprived of their liberty by a judicial or administrative decision, persons undergoing psychiatric treatment under Articles L.3212-1 and L. 3213-1.