Acute Disseminated Encephalomyelitis (ADEM)
A disseminated inflammation of the brain and the spinal cord, occurring in association with vaccination or a systemic viral infection.

Aerobic Training
Physical exercise that promotes the circulation of oxygen through the blood. Examples include running, swimming, and cycling.

Alkylating agent (cytotoxic agent)
A drug that interacts with DNA present in the cells and prevents their division.

Amino acids
Organic compounds which join to form proteins.

Analgesic drug
A drug that relieves pain.

Antiacids
Substances that attempt to neutralise gastric acid in the stomach. They are often used to counteract the iatrogenic effects of treatment.

Antibiotics
Substances produced by micro-organisms that inhibit or destroy other micro-organisms. As such (in a natural or chemically modified form) they are used therapeutically against microbial infection.

Antibody
A protein, found principally in blood, originating either normally or in response to an antigen.

Anticonvulsants
Drugs taken for epilepsy. They are usually given every day for years to prevent epileptic attacks, not to treat attacks when they actually occur. They can also be used to treat central pain.

Antidepressants
Drugs prescribed for people who are suffering from depression. They can also be used to treat central pain caused by the disease.

Antigen
Substance, which is capable, under appropriated conditions, of inducing a specific immune response and of reacting with the products of that response (as antibodies).

Anti-inflammatory drugs
Agents that counteract or suppress the inflammatory process (as corticosteroids or ACTH).

Antineoplastic agent
An agent inhibiting or preventing the growth of neoplasms, checking the maturation and proliferation of malignant cells. Using these chemical properties, it can be used to inhibit the growth of every cell, not only malignant ones.

Aphasia
A disturbance of speech in the sense that understanding and use of words is impaired. The words for things have somehow been "forgetten". There is no problem with the articulation of words. The output of speech can be very slow with the use of wrong words or maybe only just "yes" or "no" responses. Sometimes speech is fluent but makes no sense at all because the words are muddled up and non sensical.

Apheresis
An hematologic procedure in which blood products are separated from a donor (a subject). Then the desired elements are collected and the rest returned to the donor.

Artery/Arteries
The tubes which carry blood away from the heart to all the tissues and organs in the body, including the brain and spinal cord.

Astasia
Lack of muscular coordination in standing.

Ataxia
Incoordination or awkwardness in the performance of a motor task.

Attention
The act of concentrating.

Autoimmune Disease
An illness involving the formation of antibodies produced by an individual against his own tissues which appear to cause pathological damage.

Blood-Brain Barrier (BBB)
A protective barrier formed by the blood vessels and glia (supportive tissue) of the brain. It prevents some substances in the blood from entering brain tissue.

Bone Marrow Transplantation
A procedure in which marrow destroyed is replaced with treatment of high doses of anticancer drugs or radiation. The replacement marrow may be taken from the patient before treatment or may be donated by another person.

Brain Stem
The lower part of the brain which connects the main "thinking" part of the brain (cerebral hemispheres) to the spinal cord. All the nerves to and from the arms, legs and face run through the brain stem. So do the nerves controlling breathing, speaking, balance and eye movement.

Central Pain
This is a distressing problem. Some patients feel burning or stabbing pain in face or arm or leg. It can be treated with drugs that are usually used for depression or epilepsy.

Cerebellar tremors
See "Intention Tremors".

Cerebellum
The part of the brain connected to the brain stem. It is concerned with balance and making sure that movements of the limbs are smooth and well directed.

Cerebral Hemisphere
There are two cerebral hemispheres, one on the left and one on the right. They are the main "thinking" parts of the brain concerned with memory, starting movements, vision, speech, and feeling. They are by far the largest part of the human brain.

Cerebrospinal Fluid (CSF)
The water like fluid which surrounds and protects the brain and spinal cord. It also circulates in the cavities within the brain (the ventricules).

Cholesterol
A fatty substance which is found in certain foods, circulates in the blood and is used as an energetic source in the body.

Cognitive
Cognitive functions of the brain are those to do with the intellect, memory, thinking, language and working things out.

Combination Therapies 
A number of drugs used together.

Contractures
Shortening of muscles which leads to fixed and unnatural positions of the limbs. Contractures are usually due to paralysis of muscles, or sometimes fixing the limb in one position for several weeks. Attempts made to straighten out the contracted muscles can cause pain.

Corpus Callosum
The part of the brain that connects the two cerebral hemispheres together.

Corticosteroids
A group of natural hormones (or chemical modifications of same) used in an anti-inflammatory or immunosuppressive role.

CT (computerized tomography) scan
A special type of X-ray which displays not just bones (like an ordinary X-ray) but also soft tissues like the brain. It is safe, usually requires no injections, but it does require the patient to lie still for several minutes.

Cytokine
Small proteins or biological factors that are released by cells to modulate every cellular interactions (as growth or specific function).

Dementia
An acquired, persistent, more or less global impairment of intellectual, emotional, conative and cognitive functioning, due to biochemical or diffuse disease of the brain, occurring in the alert state and leading to functional incapacity.

Demyelinating Disease
Any disease associated with the destruction or removal of myelin from nerve fibers.

Demyelination
The process in which the myelin is destructed or removed from nerve fibers.

Diplopia
Seeing one object as two. It is caused by the eyes not looking in the same direction.

Dysarthria
Slurred speech so the patient may sound drunk. The content of the speech is normal. The patient can understand the speech of other people.

Dysesthesia
An unpleasant abnormal perception of any stimulus.

Dysphagia
Inability or difficulty in swallowing.

Dysphasia
The same as aphasia.

Dystonia
Sustained and patterned muscle contractions of agonist and antagonist muscles, usually leading to twisting involuntary movements which are frequently repetitive and which may progress to fixed abnormal postures or to repetitive twisting or squeezing movements.

Enteral Nutrition
Nutrition delivered via the alimentary tract, usually via a naso-gastric tube.

Epilepsy
An abnormal and intermittent electrical discharge in the brain. This causes spells of altered consciousness and often convulsive jerking of the limbs. There are many forms of epilepsy from very mild attacks of "being unaware" to prolonged and severe convulsions.

Evoked potentials
The electrical activity of nerves measured by the electrodes, which are put on specific areas of the body.

Expanded Disability Status Scale (EDSS)
A scale to describe how disabled a patient is.

Exacerbation
A newly developed or recently worsened symptoms of neurologic dysfunction.

Experimental Allergic Encephalomyelitis (EAE)
A model of inflammatory demyelinating disorders in animal having promoted the theory of an autoimmune cause for MS.

Field of Vision
The entire area that can be seen without shifting of gaze.

Hemianopia
See Homonymous Hemianopia.

Hemiparesis
A mild hemiplegia, i.e. less than complete paralysis of the upper and lower limbs on the same side on the body.

Hemiplegia
Complete paralysis of the upper and lower limbs on the same side of the body.

Homonymous Hemianopia
Impaired vision in both eyes but only affecting objects to either the left or the right of the centre. This causes patients to bump into, or ignore things, on the side affected. It may interfere with reading.

Hormone
A naturally occurring substance transmitting "messages for action" to different parts of the body. It is produced by specialised cells in the body.

Hyperbaric Oxygenation
The therapeutic intermittent administration of oxygen in a pressurised chamber.

Hyperbaric Oxygen Therapy
A pressurised chamber that allows for the delivery of oxygen in higher concentrations for therapeutic benefit.

Hyperpathia
An exaggerated or excessive perception of or response to any stimulus as being disagreeable or painful.

Hypoacusis
A reduced hearing capacity.

Hypotonia
Decrease of normal tonicity or tension, especially diminution of muscle tone.

Iatrogenic
Complication, problem or adverse reaction as a result of medical treatment.

Immune System
The body system, made up of many organs and cells, that defends the body against infection, disease and foreign substances.

Immunoglobulin
A specific protein substance that is produced by plasma cells to aid in fighting infection.

Immunosuppressive Agents (or immunosuppressants)
Any drug or agent that blocks the body's ability to fight infection or foreign substances that enter the body, suppressing the production of antibodies.

Immunotherapy
Therapy utilizing immunosuppressive agents (as acyclovir or isoprinosine) or immunosuppressive procedure (as apheresis, thymectomy, T-cell vaccination, etc.).

Incontinence
Inability to control the natural evacuation, as the fece or the urine.

Insuline-like Growth Factor
Polypeptides (contained more than two amino acids) similar to insulin and capable of eliciting the same biological responses.

Inteleukins
Polypeptides (protein substance compounded by more than two amino acids), of which there are 12 identified to date, modulate inflammation and immunity by regulating growth and functions of lymphoid and other cells.

Intention tremors
A manifestation characterised by involuntary alternating movements of the limbs brought on by voluntary movements and ceasing on rest. It is mainly due to disease as the cerebellum or of its connections.

Interferons
A family of glycoproteins proteins derived from human cells which normally has a role in fighting viral infections by preventing virus multiplication in cells. They are also given as antineoplastic agent.

Intravenous
The method of giving fluids, drugs and food through a needle or catheter into a vein, usually on the hand or in the arm.

Lumbar Puncture
A routine method by which a needle is placed in the low back to collect some cerebrospinal fluid from the space at the bottom of the spinal cord. It is seldom more than mildly uncomfortable. It can be followed by an headache on standing up.

Miosis
Constriction of the pupil.

Monoclonal Antibody
A substance, usually a protein, which can be produced in the laboratory in pure form (separated from all extraneous matter) by a single clone (derived from a single progenitor cell) of cells.

MRI (magnetic resonance imaging) scan
This uses a strong magnet and radiowaves to provide details pictures of the brain, and other internal structures of the body.

Multiple Sclerosis (MS)
An immune-mediated chronic disorder of the central nervous system (CNS) characterised by multiple areas of inflammation and demyelination.

Muscle Relaxants
A group of drugs used to produce muscle relaxation. They have their primary clinical and therapeutic uses in the treatment of muscle spasm and immobility. They have been used also for the treatment of some diseases that have in common only the presence of muscle spasms (as amantadine, aminopyridines and baclofen).

Muscle Spasms
Involuntary contractions of muscles.

Mydriasis
Dilatation of the pupil.

Myelin
A soft, white fatty material making up the myelin sheath of certain nerves.

Myelin Basic Protein
Major component of the myelin sheath in nervous system. It is an important antigen.

Myelin Sheath
An insulating stratum surrounding neurons, that dramatically increases the speed of conduction. It is formed by specialised cells of the nervous system, that can wrap around neurons up to 50 times.

Naso-gastric tube
A tube which is pushed through the nose and down into the stomach. It is used to feed patients if they are unconscious or cannot swallow.

Neurons
Any of the conducting cells of the nervous system.

Neuralgia
A sudden and violent pain which extends along the course of one or more nerves.

NMOSD
Stays for Neuromyelitis Optica Spectrum Disorder, a group of rare demyelinating, autoimmune inflammatory diseases affecting the optic nerves, spinal cord and, less often, the brain. It is also known as Devic’s disease..

Non Steroidal Anti-Inflammatory Agents
Drugs that relieve inflammation, that work by inhibition of prostaglandin production (as ibuprofen, aspirin and indomethacin).

Nystagmus
Involuntary oscillatory movement of eyeballs.

Occupational therapy (occupational therapist)
A method of treatment to help patients learn to cope with physical disabilities. Occupational therapists often help patients with activities of daily living such as bathing, feeding and toileting.

Optic Atrophy
Loss of cells and tissue from the optic nerve from whatever cause, which results in poor vision.

Optic Nerve
The nerve that carries visual information from the eye to the brain.

Optic Neuritis
Degenerative of inflammatory optic nerve lesions often associated with unilateral symptoms, characterized commonly by pain in the eye accentuated by ocular movements and variable degree of visual loss.

Oral Myelin Tolerization
An acquired decreasing response to repeated constant doses (administered orally) of antigen (myelin).

Osteoporosis
Loss of calcium from the bones making them more susceptible to damage.

Palliative care
Treatment aimed at relieving distressing symptoms and pain, in the knowledge that it will not affect the outcome of the disease.

Paralysis
Weakness.

Paraparesis
Weakness of both lower extremities.

Paraplegia
Severe weakness of both lower extremities.

Paresthesias
Tingling, crawling or burning sensation of the skin.

Pathogenesis
The mechanisms involved in the development of disease.

Pathology
Abnormality in the body caused by a disease.

Pathophysiology
The effects of disease on body function.

Peptide
A compound of two or more amino acids, which can be used as drugs.

Physiotherapy (physiotherapist)
A method of physical treatment to help patients regain lost physical functions. A physiotherapist is likely to concentrate on retraining the patient to balance and walk.

Polyunsaturated fat
See "unsaturated fat".

Primary Prevention
Interventions which attempt to reduce the risk of onset of the disease occurring for the first time. At the present, primary prevention is impossible in Multiple Sclerosis because its risk factors are unknown.

Prostaglandis
A group of compounds derived from unsaturated fatty acids. They are extremely potent mediators (capable of inducing some activity) of different physical and chemical processes, like the processes of inflammation.

Psychotherapy
A generic term for the treatment of mental illness or emotional disturbances primarily by communication with speech or with different ways other than the spoken language.

Ptosis
Drooping of the eyelid.

Rare diseases

Life-threatening or chronically debilitating diseases – mostly inherited – that affect so few people that combined efforts are needed to reduce the number of people contracting the diseases, prevent newborns and young children dying from them, preserve sufferers' quality of life and socio-economic potential.  In EU countries, any disease affecting fewer than 5 people in 10 000 is considered rare. That number may seem small, but it translates into approximately 246 000 people throughout the EU's 28 member countries. Most patients suffer from even rarer diseases affecting 1 person in 100 000 or more

Rehabilitation

This refers to the overall process of re-training people to make the best possible recovery from the attack. It is usually involves help from nurses, physiotherapists, occupational therapists and where appropriate, speech and language therapists.

Risk factors
Things which, if present, put people at high risk of occurring a disease. No risk factor is known for Multiple Sclerosis patients.

Saturated fat
This is usually the hard fat in the diet (e.g. dairy products, red meat fat). When eaten, it tends to cause an abnormally high blood cholesterol.

Scotoma
A blind or partial blind area in the field of vision.

Secondary Prevention
Interventions applied after an exacerbation to reduce the risk of a further exacerbation in Multiple Sclerosis patients.

Seizures
A term which usually refers to epilepsy.

Sepsis
The presence of micro-organisms in the blood during an infection.

Single Agent
One medicine or treatment used in isolation.

Spasticity
Increased tension in groups of muscles as a result of damage of the brain or spinal cord. Usually but not always, there is weakness of the muscles as well.

Spinal cord
The downward continuation of the brain stem. It lies within the bony canal in the spine. The cord is a cylinder of nerve tissue about 45 cm long containing bundles of nerve fibers running up and down like telephone wires, carrying messages to and from the brain to the arms, legs and every organ of the body.

Steroids
See "Corticosteroids".

Subcutaneous
Literally "under the skin". In practice, it is the way some drugs and fluids are given through a needle inserted under the skin.

Symptomatic Drug
An agent directed at the allying of symptoms (for example, the treatment for spasticity by amantadine).

Synthetic Peptide
A peptide produced in laboratory (not natural substance).

Synthetic Serum Thymic Factor
A thymus-dependent substance found in normal blood and produced in laboratory.

T-cell
Cells which are derived from the thymus, where mature and multiply. Involved primarily in controlling specific immune reactions and in the control of antibodies production. Besides T-cells produce interleukins.

T-cell Vaccination
The introduction of vaccine compound of T-cells into the body for the purpose of inducing immunity.

Thymectomy
The excision of the thymus by operation, radiation or chemical means.

Thymus
An organ of immune system, where some specific cells mature and multiply.

Total Lymphoid Irradiation
The total exposure of lymphoid organs (as lymphnodes, spleen or liver) to x-rays. In the lymphoid organs the immune system cells are located and are destroyed by irradiation.

Transforming Growth Factor (TGF) beta 
Protein, secreted by many different cell types, that can stimulate the growth of normal cells and, particularly, the wound healing. This substance is implicated in promoting inflammation processes.

Tremor
Involuntary rhytmic and regular oscillations of a body part in any plane, due to alternate or synchronous action of groups of muscles and their antagonists.

Trigeminal Nerve
The fifth cranial nerve. It transmits sensation from sharply defined cutaneous fields on the face, oral cavity and nasal passages. It also provides motor function to the muscles of mastication.

Trigeminal Neuralgia
A disorder of trigeminal nerve (cranial nerve V) dysfunction. It is characterised by excruciating unexpected attack of pain in the lips, gums, cheek or chin, and, very rarely, in the distribution of the eye (ophthalmic division of the trigeminal nerve).

Tumor Necrosis Factor (TNF) alpha
A cytokine, that preferentially kills tumor cells in vivo (within the living body) and in vitro (in an artificial environment). The TNF alpha also promotes inflammatory responses.

Tumor Necrosis Factor (TNF) alpha inhibition
Inhibition of TNF alpha production.

Unsaturated fats 
Usually the soft fat in the diet (e.g. vegetable oil) which when eaten tends to lower the cholesterol. This type of fat is also called "polyunsaturated" and this name is often found on food packaging.

Urinary Retention
Build-up of urine in the bladder due to difficulty of passing it normally.

Vaccine
A product compound of micro-organisms (with reduced infectivity or killed or their fractions, which are capable to stimulate immune responses), administered for the prevention, amelioration or treatment of infectious diseases. This term is also generally used to define every substance introduced in the body.

Vascular
To do with the blood vessels, either the arteries or the veins.

Veins
Thin-walled blood vessels containing blood at low pressure which is being returned to the heart from tissues that have been perfused by arteries.

Ventricles
The normal cavities within the brain which are filled with the water-like cerebrospinal fluid.

Vertigo
An abnormal sensation of movement which makes a person feel as if they are spinning. It is more common symptom of a problem with the ear and balance mechanisms.

Visual Acuity
Measurement of the finest details that an eye can distinguish.