What is avascular tissue?

Avascular tissue lacks blood vessels and therefore does not receive oxygen and nutrients directly from the circulatory system. Instead, these tissues obtain nutrients and oxygen through diffusion from surrounding tissues.

Examples of avascular tissues include:

- Cartilage: Cartilage is a connective tissue found in various parts of the body, such as joints, ears, and nose. It is composed of specialized cells called chondrocytes that produce and maintain the extracellular matrix, which contains collagen, proteoglycans, and water. Cartilage receives nutrients and oxygen from the surrounding synovial fluid or by diffusion from nearby blood vessels.

- Cornea: The cornea is the transparent, outermost layer of the eye that covers the front of the eyeball. It is composed of several layers of specialized cells and collagen fibers. The cornea is avascular and receives its oxygen and nutrients from the surrounding tear film and aqueous humor, a fluid that fills the anterior chamber of the eye.

- Epidermis: The epidermis is the outermost layer of the skin. It is composed of multiple layers of keratinized cells that provide a protective barrier against external factors. The epidermis is avascular and receives nutrients and oxygen from the underlying dermis, which contains blood vessels.

- Dentine: Dentine is a hard, mineralized tissue that makes up the majority of the tooth structure, located beneath the enamel. Dentine is produced by odontoblasts, cells located in the pulp cavity. Dentine is avascular and receives nutrients and oxygen from the pulp cavity through dentinal tubules, microscopic channels that extend from the pulp to the dentine surface.