Medical Glossary
attack
Same as relapse.
autoimmune disease
A process in which the body's immune system causes illness by mistakenly attacking healthy cells, organs, or tissues in the body. Multiple Sclerosis is believed by many to be an autoimmune disease, along with systematic lupus erythematosus, rheumatoid arthritis, and many others. The precise origin and pathophysiologic processes of these diseases are unknown.
Avonex
One brand of beta interferon, given once a week by intramuscular injection. A medication manufactured from naturally occurring interferons.
axon
The core nerve fiber extending from a cell body which is protected by the myelin sheath. It carries signals from a nerve cell to another nerve cell or to a muscle.
BBB
Blood-Brain Barrier.
Benign MS
Some people with MS are described as having a benign form of the disease. It is not possible to diagnose someone initially as having this form of MS, as it is only by looking at the disease ten or fifteen years after its onset that the pattern is visible. Benign MS has little impact on daily living. Individuals may experience a few mild attacks, or relapses, but no ongoing disability.
Beta Interferon
Also known as Interferon Beta. Interferons are proteins made by the body in response to a foreign stimulus (e.g. a virus) and which appear to regulate or modulate the immune system. Beta Interferon (one of the three types of interferons) appears to "calm" an overactive immune system. Beta Interferon has been shown to reduce the risk of disability progression in MS, reduce relapses, and reduce the number and size of active lesions in the brain (as shown on MRI).
Betaferon
One brand of Beta Interferon, given alternate days by subcutaneous injection.
Blood-Brain Barrier
A semi-permeable layer around blood vessels in the brain and spinal cord that prevents large molecules, immune cells, and potentially damaging substances and disease-causing organisms (such as viruses) from passing out of the blood stream into the central nervous system (brain and spinal cord). A break in the blood-brain barrier may underlie the disease process in MS.
Central Nervous System
The central nervous system consists of the brain and spinal cord, which control the main bodily functions.
chronic
Of long duration, not acute; a term often used to describe a disease showing gradual worsening.
Chronic Progressive MS
Most people with Multiple Sclerosis experience a Relapsing Remitting form of the disease. In Chronic Progressive MS, however, there is a gradual deterioration in neurological function. The degree of progression, and the time over which it takes place, vary from one person to another. Chronic Progressive MS may be Primary or Secondary in type.
Copaxone
Glutarimer acetate. A substance that has similar effects to Beta Interferon in reducing MS attacks. It is given daily by subcutaneous injection.
CPMS
Chronic Progressive MS
demyelination
Destruction of myelin, resulting in disruption in the flow of messages between the brain, spinal cord and other parts of the body.
Evoked Potential
Recordings of the nervous system's electrical response to the stimulation of specific sensory pathways(e.g. visual, auditory, general sensory). In tests of evoked potentials, a person's recorded responses are displayed on a oscilloscope and analyzed on a computer which allows comparison with normal response times. Demyelination results in a slowing of response time. EP's can demonstrate patches of damage along specific nerve pathways whether or not symptoms are present, making this test useful in confirming the diagnosis of MS.
exacerbation
Same as relapse.
flare-up
Same as relapse.
IF
Interferon (See Beta Interferon).
immune system
A complex system of various types of cells that protects the body against disease-producing organisms and other foreign substances.
incontinence
Also called spontaneous voiding; the inability to control passage of urine or bowel movements.
interferon
See Beta Interferon.
lumbar puncture
Insertion of a hollow needle into the lower spinal canal to withdraw cerebiospinal fluid (CSF) for diagnosis.
Magnetic Resonance Imaging
A diagnostic procedure which produces visual images of different body parts without the use of X-rays. Nuclei of atoms are influenced by a high frequency electromagnetic impulse inside a strong magnetic field. The nuclei then give off resonating signals which can produce pictures of parts of the body. An important diagnostic tool in MS, MRI makes it possible to visualize lesions in the white matter of the brain and spinal cord.
MRI
Magnetic Resonance Imaging.
myelin
A fatty substance which covers nerves, assisting in the passage of messages along the nerves between the brain and every part of the body.
nerve
A bundle of nerve fibers (axons). The fibers are either afferent - leading toward the brain and serving in the perception of sensory stimuli of the skin, joints, muscles, and inner organs; or efferent - leading away from the brain and mediating contractions of muscles or organs.
placebo
An inactive substance administered to a patient, usually to compare its effects with those of a real drug.
Primary Progressive MS
A form of Chronic Progressive MS, in which there is gradual deterioration from the onset of MS, without sudden relapses. About 10% of MS cases are Primary Progressive.
pseudo-exacerbation
A temporary aggravation of disease symptoms, resulting from an elevation in body temperature or other stressor (e.g. an infection, severe fatigue) and which disappears once the stressor is removed. A pseudo-exacerbation involves symptom flare-up rather than new disease activity or progression.
relapse
The appearance of new symptoms, or the aggravation of old ones, lasting at least 24 hours (also called "attack," "exacerbation," "flare-up," or "worsening"); usually associated with inflammation and demyelination in thebrain or spinal cord.
Relapsing Remitting MS
MS follows different patterns in different people. The Relapsing Remitting form of MS follows a course of relapses where there is an increased level of symptoms, followed by remissions in which there are fewer, or no, evident symptoms. The periods of acute attack occur when a patch of inflammation damages nerve fibers so that messages do not pass clearly from the brain to other parts of the body. The frequency and severity of relapses varies. Some people with Relapsing Remitting MS go on to develop Secondary Progressive MS.
remission
When the symptoms of MS get better temporarily - possibly for years.
remyelination
The repair of damaged myelin. Myelin repair occurs spontaneously in MS but very slowly. Research is currently under way to find a way to speed the healing process.
sclerosis
scarring of nerve tissue in areas of demyelination.
Secondary Progressive MS
A form of Chronic Progresive MS, in which some people who begin with Relapsing Remitting MS find that over time their symptoms gradually worsen without relapses. Some people continue to experience occasional relapses in this phase.
steroid
An organic compound, containing a carbon ring system, which has a poweful anti-inflammatory action and can also reduce blood brain barrier leakage. Used in the treatment of Relapsing Remitting MS.