Multiple Sclerosis Glossary

Abnormal Reflexes -- Muscle responses to a stimulus, which can be increased when there is a malfunctioning of the central nervous system.

Adrenocorticotropic Hormone (ACTH) -- Hormone produced by the pituitary gland, which stimulates the adrenal glands to produce cortisone.

Attack -- Sudden onset of new symptoms or worsening of old ones due to multiple sclerosis. Generally, these symptoms must last for more than 24 hours before it is considered an attack. This also may be called an exacerbation or relapse.

Ataxia -- Inability to properly coordinate movement. This usually refers to walking and movement of the arms.

Autoimmune Disease -- Conditions in which the immune system goes awry and develops a response against its own cells or tissues.

Autonomic Nervous System -- Portion of the peripheral nervous system, not under voluntary control, that governs "automatic" functions like sweating, heart rate, sexual functions and bowel movement.

Central Nervous System (CNS) -- This system consists of the brain and spinal cord, where many bodily functions are controlled, many sensations are processed and signals are sent to different parts of the body. Functions affected by the CNS include muscle control, eyesight, breathing and memory. The CNS is distinguished from the peripheral nervous system, which involves the actual nerves to and from the muscles and other body parts.

Cerebellum -- Part of the brain, located at the base, that controls balance.

Cerebral spinal fluid (CSF) -- A water-like fluid that surrounds and bathes the brain and the spinal cord.

CSF Protein -- This protein normally is dissolved in the spinal fluid and can be measured. It may be increased when there is inflammation.

Cortisone -- Hormone of the adrenal glands known to have anti-inflammatory and immune system suppressing properties. Also called glucocorticoid or steroid.

Cytokines -- Messenger chemicals released by T-cells that signal and mobilize other components of the immune system or other organs.

Decubitus -- Refer to a body position that causes undue pressure on certain parts of the body, which can lead to the eventual breakdown of skin and underlying tissue. Decubitus sores also are called bed sores or pressure sores.

Demyelinating Disease -- A disease causing loss (or damage) of myelin. Multiple sclerosis is one example of a demyelinating disease in the central nervous system, although other conditions also can lead to dymyelination.

Demyelination -- Abnormal process that leads to the loss or breakdown of myelin.

Dementia -- A deteriorated mental state due to a disease process. It can result from many disorders of the nervous system.

Dexamethasone (Decadron) -- A high potency glucocorticoid, or steroid, which is used to decrease swelling and inflamation in the nervous system.

Diplopia -- Double vision.

Dysarthria -- Slurring of speech.

Dysphagia -- Difficulty swallowing that is often due to weakness or spasm of the esophagus.

Evoked Potentials -- Diagnostic tests done using stimulation of the special senses, such as seeing, hearing and feeling, to assess the function in these CNS neural pathways.

Exacerbation -- See Attack.

Edema -- A condition in which the body tissues contain an excessive amount of fluid. For example, when there is swelling of the tissue.

Gamma Globulin -- Specific proteins found in normal human serum and human CSF which are increased in the CSF in 70 percent to 80 percent of persons with multiple sclerosis.

Immune Defect -- General term describing different malfunctions in the immune system where it either does not respond to a foreign substance by destroying or neutralizing it, or where the immune system erroneously destroys normal body structures, such as with an auto-immune disease. Examples of the latter condition are lupus erythematosus, rheumatoid arthritis and multiple sclerosis.

Immune System -- Consists of a number of different structures in the human body (lymph nodes, bone marrow, thymus gland, etc.) which produce certain types of white blood cells and antibodies that have the ability to destroy or neutralize various germs, poisons and other foreign substances.

Incontinence -- Inability to control the urinary bladder or bowels.

Intrathecal -- Within the spinal canal.

Lhermitte's Sign -- Sensation of tingling running down the middle of the back upon bending the neck forward. This can occur in different conditions involving the neck portion of the spinal cord and is sometimes felt in arms and legs as well.

Lumbar Puncture (Spinal Tap) -- Insertion of a needle into the spinal canal in order to obtain a sample of CSF and/or to inject special materials intrathecally.

Lymphocytopheresis -- Removal of white blood cells from the blood.

Magnetic Resonance Imaging (MRI) -- A technique that uses magnetic fields to produce images of deep internal body structures.

Myelin -- Fatty substance that acts as an insulator around most of the nerve fibers in the human body. Myelin is found in the central as well as the peripheral nervous system.

Multiple Sclerosis (MS) -- CNS disorder characterized by worsening, or exacerbations, and improvements, called remission, of symptoms. This leaves multiple scars, called plaques, in the CNS. Common symptoms include loss of strength, difficulty with balance and bladder control, numbness and tingling, and blurred or double vision.

Neurogenic Bladder -- A condition in which the control of urinary bladder control is disturbed. Symptoms include frequent or urgent urination, loss of the urge sensation, inability to empty the bladder even though the urge may be present or loss of bladder control, which then empties itself irregularly and spontaneously.

Nystagmus -- Abnormal eye movements consisting of repetitive jerks.

Oligoclonal Bands (Immunoglobulin G) -- Specific gamma globulin proteins that are increased in 80 percent of persons with MS.

Optic Neuritis -- Inflammation of the nerve which connects the eye with the brain. This can cause blurring or loss of vision and occasionally pain.

Paresis -- Weakness, usually in the arms and legs.

Paresthesias -- Abnormal sensations including, but not limited to, tingling, constriction and discomfort.

Peripheral Nervous System (PNS) -- Consists of all of the nerves in the body, outside the CNS, that carry signals from the CNS to the muscles and organs as well as signals from the body into the CNS.

Plaque -- Patchy area of inflammation, demyelination and sclerosis in the CNS that is characteristic of MS damage.

Plasmapheresis -- Removal of plasma, or the fluid portion of the blood that does not include cells, from the blood. This fluid contains the antibodies and its removal is an experimental treatment for MS.

Position Sense -- Ability to feel slight movements of fingers or toes and to know where body parts are in space.

Remission -- Improvement or complete disappearance of one or more of the neurological symptoms that result from MS.

Romberg's Sign -- Inability to maintain balance in the standing position with feet and legs drawn together and eyes closed.

Scanning Speech -- A type of slurred speech resulting from involvement of the cerebellum. This also is called explosive or ataxic speech.

Spasticity -- Increased resistance to muscle stretching and loss of normal elasticity of leg and/or arm muscles resulting from CNS disease process. Often manifested by muscle stiffness, which can result in difficulty moving the arms and legs.

Tremor -- Various rhythmic involuntary movements involving the arms, legs or head, occurring in numerous illnesses and conditions and greatly varying in type and severity.

Urodynamic Testing -- Specialized diagnostic tests of the bladder that measure functional integrity of the urinary system.

Vertigo -- Dizziness or a spinning sensation.

Visual Evoked Potential (VEP) -- See Evoked Potentials.

Visual Field -- Portion of space extending in all directions that can be seen by one eye without changing its position.

White Blood Cells -- Cells found in normal human blood or spinal fluid known to have protective properties and which are part of the immune system.


Reviewed by health care specialists at UCSF Medical Center.

This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.

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