avasculaires

Avasculaires is the French term for avascular, describing tissues or structures that lack blood vessels. In human anatomy, avascular regions rely on diffusion from surrounding tissues or fluids to obtain nutrients and remove waste. The absence of vasculature often confers particular functional properties, such as transparency or low metabolic demand.

Common examples include cartilage (especially articular cartilage), the cornea of the eye, the lens of the eye, and the enamel of teeth. These tissues have limited or no direct blood supply, and their resident cells (such as chondrocytes or keratocytes) live in a relatively sparse, avascular matrix. Their development and maintenance depend on diffusion from adjacent vascularized tissues or bodily fluids.

Physiological implications include slower repair and regeneration after injury, since nutrients and immune cells arrive mainly by diffusion rather than through blood vessels. Healing in avascular tissues is often limited and may proceed slowly or incompletely. For instance, cartilage has relatively low intrinsic healing capacity, while the cornea maintains transparency by avoiding vascular invasion.

Clinical relevance: the term avascular is used in diagnoses such as avascular necrosis, where blood supply to bone tissue is compromised, leading to tissue death. In ophthalmology, preserving avascularity in certain tissues (e.g., cornea) is important for function and transparency, though pathological neovascularization can impair vision. See also concepts related to vascularization and diffusion in biology.