Etiology. Ischemic stroke. Ischemic stroke is heterogenous, with over 100 pathologies implicated. According to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification system, there are 3 leading causes: large vessel disease, small vessel disease (lacunar), and cardioembolism.

Etiology is the study of causation or origination. The word is derived from the Greek word αἰτιολογία ( aitiología ), meaning "giving a reason for". More completely, etiology is the study of the causes, origins, or reasons behind the way that things are, or the way they function, or it can refer to the causes themselves.

Rheumatoid arthritis (RA) is a chronic (long-lasting) disease that mostly affects joints, such as the wrist, hands, feet, spine, knees, and jaw. In joints, RA causes inflammation that leads to: Pain. Swelling Stiffness. Loss of function. Rheumatoid arthritis is an autoimmune disorder because the immune system attacks the healthy joint tissues.

Activities What is etiology in biology? Etiology, in the fields of biology and medicine, refers to the cause of a disease. Etiologies of disease may be intrinsic, or of internal origin,.