Glossary of Medical Terms

A summary of the costs of a medical treatment or other healthcare service that an insurance company may send to a patient after the patient has received the service. An EOB usually includes the date the patient received the service, how much the service cost, how much the health insurance plan paid, and how much the patient may need to pay the healthcare provider. Also called explanation of benefits.

A type of immune cell that has granules (small particles) with enzymes that are released during infections, allergic reactions, and asthma. An eosinophil is a type of white blood cell and a type of granulocyte.

A condition in which the number of eosinophils (a type of white blood cell) in the blood is greatly increased. Eosinophilia is often a response to infection or allergens (substances that cause an allergic response).

A substance that is being studied as a treatment for cancer. It belongs to the family of drugs called cancer vaccines.

A thin membrane that lines the fluid-filled spaces in the brain and spinal cord. It is made up of a type of glial cell called an ependymal cell.

A cell that forms the lining of the fluid-filled spaces in the brain and spinal cord. It is a type of glial cell.

A type of brain tumor that begins in cells lining the spinal cord central canal (fluid-filled space down the center) or the ventricles (fluid-filled spaces of the brain). Ependymal tumors may also form in the choroid plexus (tissue in the ventricles that makes cerebrospinal fluid). Also called ependymoma.

A type of brain tumor that begins in cells lining the spinal cord central canal (fluid-filled space down the center) or the ventricles (fluid-filled spaces of the brain). Ependymomas may also form in the choroid plexus (tissue in the ventricles that makes cerebrospinal fluid). Also called ependymal tumor.

A shrub native to China and India. The stems and roots are used in traditional medicine as a diuretic and for asthma, bronchitis, and cough. It has also been promoted as a decongestant, a weight loss aid, and as a supplement to increase energy. Ephedra may cause high blood pressure, increased heart rate, or death if used with certain drugs, and may reduce the effects of certain drugs used to treat cancer and other diseases. The U.S. Food and Drug Administration has banned the sale of dietary supplements that contain ephedra. The scientific name is Ephedra sinica. Also called ma huang.

A scientist who studies the patterns, causes, and control of disease in groups of people.