- 1. The act of permeating or penetrating into a substance, cell, or tissue; said of gases, fluids, or matter held in solution. 2. The gas, fluid, or dissolved matter that has entered any substance, cell, or tissue. SYN: infiltrate (2). 3. Injection of solution into tissues, as in i. anesthesia. 4. Extravasation of solutions intended for intravascular injection.- cellular i. migration of cells from their sources of origin, or direct extension of cells as a result of unusual growth and multiplication, thereby resulting in fairly well-defined foci, irregular accumulations, or diffusely distributed individual cells in the connective tissue and interstices of various organs and tissues; used especially with reference to such changes associated with inflammations and certain types of malignant neoplasms.- fatty i. abnormal accumulation of fat droplets in the cytoplasm of cells, particularly of fat derived from outside the cells. SEE ALSO: fatty degeneration.- gray i. a term sometimes used for the relatively rapidly formed, semisolid, gray or gray-white exudate (chiefly necrotic cells and remnants of tissue, and macrophages) resulting from unusually acute, overwhelming, diffuse tuberculous infection in the lung. SYN: gelatinous i..- lipomatous i. nonencapsulated adipose tissue forming a lipomalike mass, usually in the cardiac interatrial septum where it may cause arrhythmia and sudden death. SYN: lipomatous hypertrophy.- paraneural i. SYN: perineural i..
* * *in·fil·tra·tion .in-(.)fil-'trā-shən n1 a) the act or process of infiltratingb) something that infiltrates <anesthetic drug \infiltration>2) an abnormal bodily condition produced or characterized by infiltration
* * *n.1. the abnormal entry of a substance (infiltrate) into a cell, tissue, or organ. Examples of infiltrates are blood cells, cancer cells, fat, starch, or calcium and magnesium salts.2. the injection of a local anaesthetic solution into the tissues to cause local anaesthesia. Infiltration anaesthesia is routinely used to anaesthetize upper teeth to allow dental procedures to be carried out.
* * *in·fil·tra·tion (in″fil-traґshən) [in-1 + filtration] 1. the pathological accumulation in tissue or cells of substances not normal to it or in amounts in excess of the normal. 2. infiltrate (def. 2). 3. the deposition of a solution directly into tissue; see under anesthesia.
Medical dictionary. 2011.