Glossary - C

cation

A positively charged ion; cations in the body include sodium, potassium, and magnesium.

cauda equina

A bundles of nerve roots, that look like a horse's tail, located at the end of the spinal cord.

causalgia

Intense, long-lasting burning pain usually caused by damage to a peripheral nerve.

cavity

A hole in the tooth caused by advanced decay.

CBC

Abbreviation for complete blood count?tests run on a blood sample to provide information on red cells, white cells, and platelets.

Related health topics: Acute Lymphocytic Leukemia (ALL) in Adults, Acute Lymphocytic Leukemia (ALL) in Children

CCU

Coronary care unit; A ward in a hospital that provides specialized care and extensive monitoring for patients with heart problems.

celiac disease

A disease characterized by damage to the small intestine caused by an oversensitivity to gluten, a protein found in wheat, rye, and barley. Celiac disease can interfere with the proper absorption of nutrients from food.

Related health topics: Glomerulonephritis

celiac plexus

A network of nerves in the upper abdomen; medication is sometimes injected here as part of a therapy to ease pain called a nerve block.

cell

The basic building block of all living organisms.

cell senescence

The end stage in the life of a cell when the cell can no longer divide.

cell-mediated immunity

A type of immune response mounted against viruses, certain types of parasites, and perhaps cancer cells.

cementum

The layer of tooth material that covers the root.

central (brain) fatigue

A lack of concentration or alertness as well as a sense of lethargy and loss of motivation; involves the central nervous system.

central nervous system

The brain, brainstem, and spinal cord.

Related health topics: Hemophilia, Parkinson's Disease

central sleep apnea

A disorder in which breathing repeatedly stops during sleep, because the brain doesn't properly signal the muscles that control breathing.

cerebellum

The part of the brain that controls coordinated movement.

cerebral aneurysm

A weakening and ballooning of the wall of an artery in the brain.

cerebral angiography

An invasive imaging procedure used to make detailed x-ray pictures of the blood vessels in the brain; dye is injected into the carotid arteries to highlight the blood vessels on x-rays.

cerebral cortex

The part of the brain involved in all forms of conscious experience, including thought, language, and memory.

Related health topics: Generalized Anxiety Disorder

cerebral hemorrhage

Bleeding in the brain caused by the rupture of a blood vessel; another term for hemorrhagic stroke.

cerebral infarction

A type of stroke caused when a blood vessel that supplies blood to the brain is blocked by a blood clot.

cerebrovascular

Pertaining to the blood vessels in the brain.

cerebrovascular accident

The medical term for a stroke.

cerumen

Earwax; a substance that helps keep dirt out of the ear and lubricates the skin in the ear.

cervical radiculopathy

A pinched nerve, causing sharp pain, tingling, and numbness in the areas served by the nerve.

cervical spine

The part of the spine located in the neck and consisting of the top seven vertebrae.

cervical spondyloarthropathy

Inflammatory arthritis involving the neck portion of the spine.

cervicogenic headache

Headache related to neck problems. Also called cervical headache.

challenge testing

A way of testing for food allergy, usually in double-blind experiments in which neither patient nor doctor knows which food is taken in pill form.

chemical peel

A chemical solution applied to the skin to cause it to blister and peel, revealing a new layer of skin; treatment is used to improve the appearance of the skin, reducing lines, wrinkles, age spots, and other problems.

chemonucleolysis

A treatment for low back pain that involves injecting the enzyme chymopapain into a herniated disk.

chemoprevention

Using drugs or chemicals to prevent cancer.

chemotherapy

The use of chemicals to treat disease; often used to destroy cancer cells.

Related health topics: Adenocarcinoma of the Lung, Amenorrhea, Bladder Cancer, Breast Cancer, Cardiomyopathy , Cervical Cancer, Colorectal Cancer, End-Stage Renal Disease, Ewing's Sarcoma, Fallopian Tube Cancer, Female Infertility, Head and Neck Cancer, Lung Cancer Overview, Melanoma, Multiple Myeloma, Myelodysplastic Syndromes, Neuroblastoma, Ovarian Cancer, Prostate Cancer, Radiation Therapy, Small Cell Lung Cancer, Spinal Cord Tumors, Squamous cell carcinoma of the lung

Cheyne-Stokes respiration

Abnormal breathing where cycles of deep, labored breathing are followed by cycles of weak breathing that can result in a total, temporary lack of airflow.

chiropractor

Someone who treats disease by manipulation and adjustment of body structures, often the spine.

chlorophyllin

A chemical found in green, leafy vegetables thought to help prevent cancer.

chlorosis

Severe iron-deficiency characterized by a yellow-green tinge to the skin.

cholagogue

A substance that causes the gallbladder to squeeze, increasing the discharge of bile.

cholecystokinin

A hormone that signals the gallbladder to contract, releasing bile, and causes the pancreas to release enzymes used in digestion.

choleretic

An agent that promotes bile production.

cholesterol

A waxy, fat-like substance produced by the liver and found in all food from animal sources; an essential component of body cells and a precursor of bile acids and some hormones.

Related health topics: Coronary Artery Disease, End-Stage Renal Disease, Heart Failure, Hypothyroidism , Liver Cancer, Obesity, Peripheral Arterial Disease , Type 2 Diabetes Mellitus

cholinergic neuron

A nerve cell that produces acetylcholine.

chondrocalcinosis

Arthritis caused by calcium crystals.

chondrocyte

A cartilage cell.

chondromalacia

A painful condition caused by irritation to or wearing away of the cartilage on the underside of the knee cap; known as runner's knee.

choroid

A thin layer of blood vessels and connective tissue between the white of the eye (sclera) and the retina.

chromosome

A threadlike structure, found in the nucleus of each cell, that carries almost all of a cell's genes.

Related health topics: Fragile X Syndrome , Muscular Dystrophy, Myelodysplastic Syndromes

chronic

Any condition that lasts a long time or recurs over time.

Related health topics: Bulimia, Esophageal Cancer, Flu (Influenza), Hepatitis B, Sickle Cell Anemia, Stomach Cancer

chronic fatigue syndrome (CFS)

A disorder of ongoing, severe tiredness that interferes with a person's ability to function well, isn't improved with rest, and isn't caused by another illness.

chronic kidney disease

Any type of kidney disease that lasts longer than three months and impairs kidney function.