Terms /
Definitions with an overview of
Arnold
Chiari (“ kee ar E” ) Malformation
Information
compiled by: Lisa Struss, Speech
Pathology Graduate Student,
Anencephaly: A Neural Tube Defect (NTD) that
occurs when the cephalic (head) end of the neural tube fails to close, usually
between 23rd and 26th days of pregnancy, resulting in the
absence of a major portion of the brain, skull and scalp. Infants with this disorder are born without a
forebrain consisting mainly of the cerebrum, which is responsible for thinking
and coordination. The remaining brain
tissue is often exposed; it is not covered by bone or skin. Infants born with anencephaly are usually blind,
deaf and unconscious (interruption of awareness of oneself and one’s
surroundings. Lack of
the ability to notice or respond to stimuli in the environment). Although some
individuals with anencephaly may be born with a rudimentary brain stem, the
lack of a functioning cerebrum permanently rules out the possibility of ever
gaining consciousness. Reflex actions
such as respiration (breathing) and responses to tough or sound may occur. The disorder is one of the most common disorder of the fetal central nervous system. Approximately 1,000 to 2,000 babies are born
with anencephaly each year in the
Aplasia: Failure to develop.
Apnea: (Greek
“Apnea” meaning “Want of breath”) The
absence of breathing. There are three
types or forms of apnea: blockage of the airways, cessation of respiratory
effort (usually brain related and referred to as “central”) and a combination
of airway blockage and central apnea. Central apnea is characterized by brief
interruptions of breathing during sleep. Occurs when brain fails to send the
appropriate signals to the breathing
muscles to initiate respiration. Obstructive sleep apnea is much more common than central
apnea. Obstructive occurs when air
cannot flow in or out of a person’s nose or mouth, although efforts to breath
continue. The throat collapses during
sleep causing the individual to snort and gasp for breath. Hundreds of these episodes can occur every night causing daytime
sleepiness and it is thought increasing the risk of hypertension (high blood
pressure) and heart problems. Disorder of breathing during sleep. It usually occurs in association with fat
build up or loss of muscle tone with aging.
These changes allow the windpipe to collapse during breathing when
muscles relax during sleep. It also
occurs if the neurons that control breathing malfunction during sleep.
Arachnoiditis: Inflammation of the middle
layers of the membranes covering the brain and spinal cord.
Arrhythmia : Abnormal heart rhythm. In
arrhythmia the heartbeats may be too slow, too rapid, too irregular or too
early. Rapid arrhythmias (greater than
100 beats per minute) are called tachycardias. Slow arrhythmias (slower than 60 beats per
minute) are called bradycardias.
Irregular heart rhythms are called fibrillations (as in atrial
fibrillation and ventricular fibrillation).
When a single heartbeat occurs earlier than normal, it is called a
premature contraction.
Articulation: Vocal tract movements for speech
sound production; involves accuracy in placement of the articulators, timing,
direction of movements, force extended, speed of response and neural
integration of all vents.
Articulators: Organs of the speech mechanism
which are involved in the production of speech:
a. cheeks, alveolar ridge, teeth, lips, lower jaw, velum, tongue, and pharynx
which serve to interrupt or modify the voiced or unvoiced air stream into
meaningful sounds. b. larynx, which creates
sound energy (phonation), c. resonators, cavities (pharyngeal,
laryngeal, oral and nasal) whose changes in size and shape alter the
fundamental vibrations produced by the vocal folds, d. respiratory
system (lungs and air passages), which furnishes the air necessary for the
production of sounds.
Aspiration: Accidental sucking in of food particles or
fluids into the lungs.
ADHD (Attention Deficit Hyperactive Disorder): ADHD is a condition that
refers to individuals inability to control their own
behavior or impulses. It can be
manifested as constant movement and fidgeting.
These individuals have difficulty blocking out noise or other stimuli in
order to focus on a task or what is being said.
It is a chronic problem that can be seen as early as infancy and can
extend into adulthood. There are two
types of Attention Deficit Disorder. The
most obvious is ADHD. The primary
characteristic is hyperactivity, which is first seen before a child even enters
school. The less obvious type is ADD,
where hyperactivity is NOT present. The
primary characteristic of this type is inattentiveness.
Brainstem: It
is the stem like part of the brain that is connected to the spinal cord, or
conversely, the extension of the spinal cord up into the brain. The brain stem is small but important. It manages going between the brain and the
rest of the body and it also controls basic body functions such as breathing,
swallowing, heart rate and blood pressure.
The brain stem also controls consciousness and determines whether
someone is awake or sleepy. The brain stem is also associated with most of the
special senses (vision and hearing in particular), and it controls muscular
activity in the head and part of the neck.
The brainstem consists of the midbrain, pons,
and medulla oblongata.
To see a
picture: www.waiting.com/brainstem.html#anchor580032
Cardio Vascular System: Is the circulatory system, which is comprised of the
heart, lungs and blood vessels.
Central Nervous System: Also known as CNS: consists of two major parts: the
brain, which is the center of neural integration, and the spinal cord, which
contains billions of
neurons that run to and from the brain and also mediates
many of the body’s reflex responses. The CNS is covered by three meninges (singular : meninx), composed of
connective tissue. In order, from
outside in, we have the dura mater, pia mater and the arachnoid
membrane. The CNS is bathed in
cerebrospinal fluid. The CNS functions
in body orientation and coordination, assimilation of experiences, and
programming of instructional behavior. The nervous system is the body of tissue
that records and distributes information in the body using electrical and
chemical transmission. It has two
parts. The
“central” nervous system is comprised of the brain and spinal cord. The “peripheral” nervous system is the nerve
tissue that transmits sensation and motor information back and forth from the
body to the central nervous system.
See CNS nerves at: www.publish.uwo.ca/~jkiernan/wholens.jpg
Cerebellar Tonsils: 1. Two appendages of the brain
at the base of the cerebellum.
2.
They are
rounded areas on the undersurface of each cerebellar hemisphere.
Cerebellum: It is an important integrating center for
coordinated regulation of limb movement, balance and structure. ’s function is for balance and
coordination. It is that portion of the
brain located at the posterior base of the cranial cavity beneath the occipital
and temporal lobes of the cerebrum. It
is attached to the medulla, pons, and midbrain of the
brainstem by three pairs of tracts, which connect it with the cerebrum, brainstem,
and spinal cord and enable it to coordinate body motor function initiated by
the cerebrum and to maintain muscle tone and equilibrium.
To see a
picture: www.com/brainfuncthree.html
www.waiting.com/brainanatomy.html#anchor2684498
Cerebral: Of or pertaining to the brain or skull
cavity.
Cerebral Hemisphere: The two
halves of the cerebrum.
Cerebral Spine: Bones in the upper neck. There
are seven of them (C1-C7)
Cerebrum: The largest part of the brain. It is divided into two hemispheres or
halves. The word cerebrum is the Latin
word for “brain.” The Romans used the
same word to refer to the “skull,” (which houses the brain) and the “head”
(which houses the skull) And in
Cerebrospinal fluid also known as
CSF: Protein rich liquid, which cushions and nourishes the brain. This fluid also surrounds the delicate brain
and spinal cord, cushioning it against injury.
Cerebrum: It controls most sensory and motor
activities; reasoning, memory, intelligence, etc. instinctual and limbic
(emotional) functions. It is usually associated with higher brain functioning,
such as speech and rational thought. It
is the largest portion of the brain, consisting of paired right and left hemispheres
united by the corpus callosum beneath the
longitudinal fissure.
Cervical Spine: The neck region of the spinal column (the cervical spine) consists of
seven bones vertebrae) shaped like building blocks, which are separated from
one another by shock absorbency pads (intervertebral
discs).
CNS: See above:
Central Nervous System
Comprehension: Knowledge or understanding of an
object, situation, event or verbal statement.
In speech, it is the understanding of spoken utterances, as
distinguished from producing utterances.
Congenital: Acquired
at birth or during uterine development as a result of hereditary or
environmental influences.
Corpus Callosum: A prominent band of fibers that unites the two
hemispheres of the brain.
Cranial Nerves: There are twelve pairs of cranial nerves that are usually recognized and
are referred to by Roman numerals and by names.
They are numbered according to their emergence from the brain stem. The names of the cranial nerves reflect
function. They merge from the central
stalk of the human brain, and 31 pairs of spinal nerves extend from the spinal
cord out between the vertebrae of humans.
For the most part the cranial nerves supply
nerves to tissues and organs of the head and neck, where as the spinal nerves
innervates the chest, abdomen and limbs. See:
www.teaching-biomed.man.ac.uk/resources/wwwcal/cranial_nerves/page2.asp#Vagus
AND/OR
www.publish.uwo.ca/~jkiernan/crncomp.htm
Cyanotic (cyanosis): A bluish discoloration of the skin (includes nail
beds, feet, nose, ears, lips, fingers, toes) or mucous membranes caused by a
lack of oxygen in the blood.
Diplopia: Diplopia is a condition whereby a single
object appears as two objects. Also called, “double vision.”
Dizziness: A medically indistinct term, which is used to
describe a variety of conditions, including lightheadedness, near loss of
consciousness, unsteadiness and vertigo.
Dysphagia: Injury or disease almost anywhere in the head and neck can lead to dysphagia. Dysphagia is difficulty in swallowing due to problems in
muscle control; may include inflammation, compression, paralysis, weakness, or hypertonicity of the esophagus. Dysphagia comes from the Greek word phagein meaning to eat. Dysphagia can occur
anywhere along the path from the lips to the stomach. Speech Language Pathologists are primarily
concerned about problems in the oral cavity,
pharynx, or larynx.
Similarly, gastroenterologists (physicians who diagnose and treat
disorders of the esophagus, stomach and intestinal tract) also use the term dysphagia when referring to esophageal dysphagia.
Dysphonia: Dysphonia
is a voice disorder also called dystonia caused by
involuntary movements of one or more muscles of the larynx or voice box. People who have spasmodic dysphonia
may have occasional difficulty saying a word or two or they may experience
sufficient difficulty to interfere with communication. Spasmodic dysphonia
causes the voice to break or to have a tight, strained or strangled
quality. There are three different types
of spasmodic dysphonia: adductor spasmodic dysphonia, abductor spasmodic dysphonia
and mixed spasmodic dysphonia.
Adductor spasmodic dysphonia: Here sudden involuntary muscle movements or spasms
cause the vocal folds/cords to slam together (adduct) and stiffen. These spasms make it difficult for the vocal folds
/cords to vibrate and produce voice.
Words are often cut off or difficult to start because of the muscle
spasms. Therefore speech may be choppy
and sound similar to stuttering. The
voice of an individual with adductor spasmodic dysphonia
is commonly described as strained or strangled and full of effort. Surprising the spasms are usually absent
while whispering, laughing, singing, speaking at a high pitch or speaking while
breathing in. Stress, however, often
makes the muscle spasms more severe.
Abductor spasmodic dysphonia: In abductor spasmodic dysphonia,
sudden involuntary muscle movements or spasms cause the vocal folds/cords to
open (abduct). The vocal folds/cords
cannot vibrate when they are open. The
open position of the vocal folds/cords also allows air to escape from the lungs
during speech. As a result, the voices
of these individuals often sound weak, quiet and breathy or whispery. As with adductor spasmodic dysphonia, the spasms are often absent during activities
such as singing or laughing.
Mixed spasmodic dysphonia: Mixed spasmodic dysphonia
involves muscles that open the vocal folds/cords as well as muscles that close
the vocal folds/cords and therefore has features of both adductor and abductor
spasmodic dysphonia.
Encephalocele:
Portion of the brain
protruding out from the occipital region in a skin-covered sac.
Esophageal: Relating to the esophagus.
Esophagus: Is part of the digestive tract. It is a tube that connects the throat with
the stomach. It lies between the trachea
(windpipe) and the spine. In an adult
the esophagus is about 10 inches long.
When a persons swallows, the muscular walls of the esophagus contract to
push food down into the stomach. Glands
in the lining of the esophagus produce mucous, which keeps passageway moist and
makes swallowing easier. It is supplied by the vagus
(X cranial nerve) nerve.
Esophageal Reflux: conditions where in the stomach contents regurgitate, or back up
(reflux) into the esophagus. (a long cylindrical tube
that transports food from the mouth to the stomach). The food is partially digested by stomach
acids content refluxes backwards up into the esophagus, occasionally reaching
the breathing passages, causing inflammation and damage to the esophagus, as
well as to the lung and larynx (voice box).
The process is medically termed Gastro Esophageal Reflux Disease
(GERD). GERD can lead to scarring and
stricture of the esophagus, requiring stretching (dialating)
of the esophagus. 10% of patients with
GERD develop Barrett’s esophagus, which can increase the risk of cancer of the
esophagus. 80% of patients with GERD also have a hiatal
hernia.
Folic Acid:
One of the B vitamins that is a key factor in the making of nucleic acid (DNA
and RNA)
Foramen: A natural opening, a hole particularly
through a bone.
Foramen Magnum: A large hole at the base of the skull, which allows passage of the spinal
cord.
To see a
picture: www.teaching-biomed.man.ac.uk/student_projects/2001/mnbf8ao2/enlarged/accessory%20foramen%20magnum.htm
www.univ.trieste.it/~brain/NeuroBiol/Neuroscienze%20per%20tutti/skull.html
Fossa: A pit or hollow.
Gastroesophageal Reflux: See esophageal reflux.
Hemisphere: Half of a spherical structure; usually used
in reference to brain structures.
Hernia /Herniation: Protrusion of an organ or other bodily structure through the wall that
normally contains it; a rupture.
Hindbrain
(rhombencephalon):
A term that describes it’s shape (Greek rhombos),
a spinning top. It is divided into a metencephalon (Greek meta, after + enkephalos, brain)
and a myelencephalon (Greek myelos, marrow). In the adult the myelencephalon,
an enlarged region where the spinal cord merges into the brain, is called the medulla
oblongata. The fluid filled central
canal of the spinal cord also enlarges in the hindbrain, where it is known as
the fourth ventricle.
The upper portion of the hindbrain is called the metencephalon. The
prominent dorsal region of the metencephalon is
formed by the cerebellum (little brain), while
ventrally the metencephalon is an upward continuation
of the medulla oblongata called the pons.
Hydrocephalus: Greek “hydro”/ water and “cephalus” / brain.
Hydrocephalus is an abnormal accumulation of Cerebral Spinal Fluid (CSF)
in the brain. The CSF is often under
increased pressure and compresses (squeeze) and damages the brain. Hydrocephalus is a condition that can arise
before birth or at anytime afterward and so it can be congenital or
acquired. It can be due to many causes
including birth defect, hemorrhage into the brain, infection, disease,
meningitis, stroke, tumor or head injury.
Most forms of hydrocephalus are the result of an obstructed flow of CSF
in the ventricles (normal cavities in the center of the brain). With birth defects the physical obstruction
of the CSF flow through the ventricles is usually the cause of hydrocephalus.
In older children
and adults there is no head enlargement form the hydrocephalus (because the
skull bones are all fused together and cannot permit enlargement) Symptoms may
include; headache, nausea, vomiting and sometimes blurred vision. There may be problems with balance and
coordination and delayed development in walking and talking in young
children. Irritability, fatigue,
seizures and personality changes such as an inability to concentrate or remember
things may also develop. Drowsiness and
double vision are common symptom of hydrocephalus progresses.
Hydromyelia: An abnormal enlargement of the central canal
of the spinal canal with an abnormal accumulation of fluid.
Hypoplasia: Underdevelopment or incomplete
development of a tissue or organ. For
example there can be hypoplasia (underdevelopment) of
the enamel of the teeth. Hypoplasia is less drastic than aplasia
where there is no development at all.
Laryngeal: See Larynx.
Larynx: also
known as the “voice box”
The larynx is the primary organ of phonation. The larynx is the portion of the breathing or
respiratory tract contains the vocal cords that produces vocal sound. It is located between the pharynx and the trachea. The larynx also called the “voice box” is a 2
inch long, tube shaped organ in the neck.
We use the larynx when we breathe, talk or swallow. Its outer wall of cartilage forms the area of
the neck referred to as the “Adams Apple.” The vocal cords/folds are two bands
of muscle that form a “V” inside the larynx.
Each time we breathe in air goes into our nose or mouth, then through
the larynx, down the trachea and into our lungs. When we breathe out, the air goes the other
way. When we breath
the vocal cords/folds are relaxed and the air moves through the space between
them without making any sound. When we
talk the vocal cords/folds tighten up and move closer together. Air from the lungs is forced between the vocal cords/folds
and makes them vibrate, producing the sound of our voice. The tongue, lips and teeth for this sound
into our words. The esophagus, a tube that
carries food from the mouth to the stomach is just behind the trachea and the
larynx. The opening of the esophagus and
the larynx are very close together in the throat. When we swallow, a flap called the epiglottis
moves down over the larynx to keep food out of the windpipe (trachea).
Lethargy: Abnormal drowsiness, stupor.
Malformation: A physical defect present at
birth.
Medulla Oblongata (Myelencephalon) : It is the base of the brain, which is formed
by the enlarged top of the spinal cord.
This part of the brain directly controls breathing, blood flow and other
essential functions. (E.g., respiration, heart rate,
vasoconstriction).
To see a
picture: www.waiting.com/brainstem.html#anchor543500
To see a
picture: www.com/brainfuncthree.html
Meninges (singular: meninx): The
Central Nervous System (CNS) is covered by three meninges
(singular is meninx), composed of connective
tissue. In order, from outside in, we
have the dura mater (the most
resilient of the three), the arachnoid membrane,
and the pia mater.
To see a
picture:
www.univ.trieste.it/~brain?neuroBiol/Neuroscienze%20per%20tutti/cover.html
Meningomyelocele see spina bifida: Meningomyelocele is protrusion of the membranes that
cover the spine but some of the spinal cord itself through a defect in the bony
encasement of the vertebral column. The
bony defect is spina bifida.
Meningeal membranes: See Meninges
Metencephalon:
Upper portion of the
hindbrain. See hindbrain.
Midbrain (mesencephalon): connecting the diencephalons and pons
is a short narrow pillar containing a center for visual reflexes.
To see a
picture: www.com/brainfuncthree.html
Myelencephalon:
See medulla oblongata.
Myelodysplasia (MDS): Disease of the bone marrow and blood platelets. Patients with MDS - the
bone marrow produces too few red blood cells, white blood cells and
platelets. Common symptom is anemia.
Nerve: A bundle of fibers that uses electrical and chemical
signals to transmit sensory and motor information from one body part to
another.
Nervous System:
See Central Nervous System.
Nuclei: nerve cells
Neural Tube Defect (NTD): NTD is a birth defect
caused by abnormal development of the neural tube. (Neural Tube is the structure present during
embryonic life, which gives
rise to the central nervous system – to the brain and spinal
cord. The best known neural tube defects
are anencephaly (absence of the cranial vault and absence of most or all of the
cerebral hemispheres of the brain), and spina bifida (an opening in the
vertebral column protecting the spinal cord), sometimes with a meningomyelocele
(protrusion of the meningeal membranes that cover the
spinal cord). The risk of neural tube
defects can be lowered if the mother’s diet before and during pregnancy
contains adequate folic acid.
Nystagmus: Rapid rhythmic repetitious involuntary eye
movements. Nystagmus can be horizontal,
vertical or rotary.
Pharynx: It is a hollow tube about 5 inches long that
starts behind the nose and ends at the top of the trachea (windpipe) and esophagus
(the tube that goes to the stomach).
Phonation: The production of many speech sounds requires
that vocal folds vibrate. This vibration
is known as phonation, voice, or voicing.
Pons:
A specific section of the
brain formed by the rounded prominence on the front surface of the brainstem. (the brain stem is the lowest part of the brain that merges
with the spinal cord; it consists of a structure called the medulla oblongata,
the midbrain and the pons). Cranial nerves V, VI,
VII, and VIII take origin at the
boarder of the pons.
Pons is Latin for “bridge.” It functions as a
bridge to join the two hemispheres of the cerebellum and to connect the cerebellum
with the cerebrum and with the spinal cord.
To see a
picture: www.com/brainfuncthree.html
To see a
picture: www.waiting.com/brainstem.html#anchor561399
Regurgitation: A backward flowing. For example of food or
liquid.
Respiratory System: The respiratory system is composed of the air passageways (nasal
cavity, pharynx, larynx, and trachea ) and lungs. Within the lungs, the trachea branches into
the bronchi, bronchioles and finally alveoli.
Sensorineural Hearing Loss: Hearing loss due to damage to the pathway for sound
impulses from the hair cells of the inner ear to the auditory nerve and the
brain.
Shunt: To bypass or divert an accumulation of fluid
to an absorbing or excreting system by surgical reconstruction OR by a
mechanical device as for the relief of hydrocephalus.
Spine: The column of bone known as the vertebral
column, which surrounds and protects the spinal cord. The spine can be categorized according to the
level of the body: i.e.: cervical spine (neck), thoracic spine (upper and
middle back) and lumbar spine (lower back).
Spinal Canal: A canal (tube, duct or passageway) that contains the spinal cord.
The major column of nerve tissue that is connected
to the brain lies within the vertebral canal, and from which the spinal nerves
emerge. The spinal cord and brain
constitute the central nervous system.
The spinal cord consists of nerve fibers that transmit nerve impulses to
and from the brain. Like the brain, the
spinal cord is covered by three connective tissue envelopes called the meninges. The space between the outer and middle
envelopes is filled with cerebrospinal fluid (CSF), a clear colorless fluid
that cushions the spinal cord against jarring shock. There are 31 pairs of spinal nerves that
originate in the spinal cord: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and
1 coccygeal.
In the spinal cord, information about internal and external conditions
travels up the ascending tracts to the brain.
This information is processed by the brain and
Spinal Stenosis: Narrowing of the spinal canal.
The result is compression of the nerve roots or spinal cord by bony
spurs or soft tissues such as discs, in the spinal canal. When the neck is affected, it can result in
unusual sensations in the arms and / or poor leg function and
incontinence.
Syncope (fainting):
Pronounced sin-ko-pea. Syncope is a partial or complete loss of
consciousness with interruption of awareness of oneself and ones
surroundings. When loss of consciousness
is temporary and there is spontaneous recovery, it is referred to as syncope,
or in non-medical terms – fainting.
Syncope is due to a temporary reduction in blood flow and therefore a
shortage of oxygen to the brain. This
leads to lightheadedness or a “black out” episode - a loss of consciousness.
Syringomyelia (pronounced sear-In-go-my-ELL-ya):
This is a disorder in which a cyst forms in the spinal cord due to an
obstruction of the normal flow of cerebrospinal fluid (CSF) redirecting it to
the spinal cord itself. This obstruction
in the flow of CSF results in the formation of a syrinx (a cyst that fills with
CSF). When this happens, pressure
differences along the spine causes the fluid to move within the cyst. It is believed that this continual movement
of fluid results in cyst’s growth (the cyst or syrinx expands and elongates
over time) and further damages the spinal cord and connecting nerves.
Syrinx: This is a cyst that forms within the spinal
cord. A syrinx / cyst may develop in the
cervical region of the spinal cord of those who have ACM. This is because ACM obstructs the normal flow
of Cerebral Spinal Fluid (CSF), redirecting it to the spinal cord itself. This results in the formation of a syrinx (a
cyst that fills with CSF). See syringomyelia.
Tinnitus: Tinnitus is a sensation of sound in the head,
which may be localized in one or both ears; it may also be perceived in the
cranial region. It can be perceived as
any of the following: throbbing, hissing, whistling, booming, clicking,
buzzing, roaring, or high pitched tone or noise. Tinnitus may result from any auditory
impairment in any location within the auditory pathway or have a vascular or
muscular origin. It is often associated
with Meniere’s disease and otosclerosis.
One of the most common causes of tinnitus is damage to the microscopic
endings of the hearing nerve in the inner ear.
Torticollis: It is a state of inadequate
muscle tone in the muscles of the neck that control the position of the
head. It can cause the head to twist and
turn to one side, and the head may also be pulled forward or backward.
Trachea: Also known as the “windpipe”. The trachea is a tube like portion of the
breathing or “respiratory” tract that connects the larynx (voice box) with the
bronchial parts of the lungs.
Vagus Nerve: It is the tenth cranial nerve. It is a remarkable nerve that supplies nerve
fibers to the pharynx (throat), larynx (voice box), trachea (windpipe) lungs,
heart, esophagus and the intestinal tract as far as the transverse portion of
the colon. The vagus
nerve also brings sensory information back to the brain from the ear, tongue,
pharynx and larynx. It originates in the
medulla oblongata, as part of the brain stem and wanders all the way down from
the brain stem to the colon. The
consequence is laryngeal palsy, paralysis of the larynx (voice box) on the
affected side. Laryngeal palsy can also
be caused by damage to the vagus nerve before it
gives off the recurrent laryngeal nerve.
www.teaching-biomed.man.ac.uk/resources/wwwcal/cranial_nerves/page2.asp#Vagus
AND/OR
www.publish.uwo.ca/~jkiernan/crncomp.htm
Ventricle(s): Ventricles are pockets filled with Cerebrospinal
Fluid (CSF) which flows around the brain and spinal cord. CSF normally flows through the ventricles
down through the posterior fossa and into the spinal cord. The fourth ventricle
is in the cerebellum
or brainstem area.
Vertebral Column: The 33-vertebra fit together to form a flexible, yet extraordinary
tough column that serves to support the back through a full range of
motions. It also
protects the spinal cord, which runs from the brain through
the hollow space in the middle of the vertebral column. There are seven cervical (C1 – C7), twelve
thoracic (T1 - T12), five lumbar (L1 - L5), five sacral (S1 -
S5) with four coccygeal
vertebrae in this column, each separated by intervertebral
disks.
Vertigo: A feeling that you are dizzily turning around
or things are dizzily turning about you.
Vertigo is a medically distinct from dizziness.
Vocal Fold(s): Also known as vocal
cords. The vocal cords/folds are two bands of muscle that form a “V” inside
the larynx. These muscles vibrate to
produce the voice. The vocal folds/cords
form a “V” inside the larynx, a 2-inch long tube shaped organ in the neck. Each time we breath
in air goes into our nose or mouth, then through the larynx, down the trachea and
into our lungs. When we breathe out, the
air goes the other way. When we breath the vocal cords/folds are relaxed and the air moves
through the space between them without making any sound. When we talk the vocal cords/folds tighten up
and move closer together. Air from the
lungs is forced between the vocal cords/folds and makes them vibrate, producing
the sound of our voice. The movements of
the tongue, lips and teeth help to form this sound into our words.
Vocal Fold Paralysis: Inability of one or both vocal folds (vocal cords)
to move. The paralysis is usaully due to damage to the nerves going to the vocal
folds/cords or due to damage to the brain itself.
In more technical terms:
Vocal fold/cord paralysis may result in
lesions in the: nucleus ambiguus or its supranuclear
tracts in the brain, the main trunk of the vagus
nerve (see cranial nerves) , or in the recurrent
laryngeal nerves (which supply the larynx), intracranial (brain) tumors,
strokes, and demyelinating diseases can cause nucleus
ambiguus paralysis. Neoplasms at the base
of the skull and trauma of the neck can cause paralysis of the vagus nerve. Recurrent laryngeal paralysis is caused
by neck or thoracic lesions (such as aortic aneurysm, mitral stenosis, tumors
of the thyroid gland, esophagus, lung or neurotoxins (such as lead), infections
(such as diphtheria), cervical spine injury or surgery or viral illness.
OVERVIEW OF
Arnold Chiari Malformation (ACM) is congenital abnormality at the base of the brain in which a portinion of the cerebellum (cerebellar tonsils) protrude
below the level of the Foramun Magnum. Arnold Chiari
is divided into four groups or types to as related to the degree of
displacement/herniaition.
Pathogenesis:
The
cause is unknown. There are many
speculations/theories related to the cause but none really explains all the
malformations. Some literature make note of a small or underdeveloped occipital
bone that limits the room in the base of the skull for the hindbrain, thus
resulting in displacement/herniation as a cause.
Although
Type II is very often associated with Neural Tube Defects (NTD), such as spina
bifida, hydrocephalus et cetera, it is not considered a NTD.
Clinical Presentation:
There
are four types (I, II, III, IV) and clinical presentation are highly variable. May be associated with
other anomalies.
Type I presentation is
characterized by a downward displacement (herniation) of the cerebellar tonsils
and fourth ventricle through the foramen magnum around the cervical spinal cord.
To see a picture: www.pressenter.com/~wacma/csf.htm.
or www.yvy69.ukgateway.net/1/basic.htm#top
There is also obstruction of
the normal flow of Cerebral Spinal Fluid (CSF) through this area because the
tonsils of the cerebellum are stuffed into the foramen magnum. Sometimes this can result in brain stem
compression, and/or the brainstem appears atrophic (shrunken) and may stick to
the spinal cord. Usually ACM Type I
occurs in adults around the third or fourth decade of life. Most people with
ACM Type I may have no obvious symptoms.
It is very rare for trauma to “cause”
Chiari, but trauma can “trigger”
symptoms in a Chiari patient even if they never had symptoms before.
~disordered esophageal motility ~chest pain ~slowness
and slurred speech ~ataxia
~bilateral vocal fold paralysis ~apnea ~choking
~ general muscle weakness
~dysphonia ~drooling
~gastroesophageal reflux
~dysphagia
~sensorineural hearing loss ~nystagmus: ~numbness
~vertigo intolerance
to ~sensation
of hot extremities
~tinnitus bright
light ~weakness
/ fatigue
~diplopia ~headache
LANGUAGE
~difficulty tracking ~syncope
~word retrieval difficulties ~pain/pressure
behind eyes ~weight loss
~fusion of cervical spine
segments
~back
pain
~cervical
pain
~headache induced by coughing
~fatigue
~vertigo
~pressure
on neck
~neck
spasms
~neck
pain
~
jaw / ear / eye pain
~insomnia
~tingling
extremities
~hand
tremors
~vomiting
~coughing
Type
II usually diagnosed at birth or infancy.
It is characterized by a further downward displacement (herniaition) of the cerebellar tonsils and fourth ventricle
at the foramen magnum into the cervical spinal cord. A kink in the medulla
occurs in 55% of the cases of Type II which may cause brain stem or cervical
cord compression. Type II is almost
always associated with spina bifida, and hydrocephalus and all their clinical
problems.
PHONATION RESPIRATION ARTICULATION MOTOR IN GENERAL
~apnea ~slowness
& slurred ~ataxia
~vocal cord paralysis ~tracheal
aspiration ~motor & sensory disorders
~gastroesophageal reflux ~gagging
~muscle weakness of the
~cricopharyngeal ~achalasia
face/hands/legs/arms
~pharyngoesophageal ~swallowing
difficulties
dysmotility ~drooling
~weak cry
~perceptual motor prblms
~dysphagia
~torticollis
AUDITORY VISUAL
LANGUAGE
OTHER
~deafness ~diplopia
(double vision) ~learning disabilities ~sensory disturbance
~blurred
vision ~comprehension
prblms ~bilateral
upper arm
~pragmatic prblms weakness and wasting
~cyanotic
spells
~neck
pain
~arrhythmias
~syncope
(fainting)
~vomiting
~varying degrees of mental
impairment
~bradycardia
(slow heart)
~ADHD
~memory problems
~lethargy
~seizures
~ syringomyelia
~syrinx
~ incontinence
Rare. Diagnosed at birth, Type III consists of
further herniation of the entire cerebellum below the foramen magnum often
forming an encephalocele. What this basically means is that the back
of the brain protrudes out of an opening in the back of the skull area. These individuals have portions of the
cerebellum and brainstem in the upper spinal canal.
Very Rare. Type IV is also diagnosed at
birth. Type IV is in fact not a hindbrain
herniation at all in contrast to Types I – III.
It is associated with underdeveloped (hypoplasia)
cerebellum or a failure to develop (aplasia). In Type IV the back of the brain fails to
develop normally. Usually back portions
of the head and spinal column are open to the outside.
DIAGNOSIS:
Type I: Due to the vague nature of the symptoms and the
variable course, misdiagnosis is common.
Patients are frequently diagnosed with Multiple Sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS), Myasthenia Gravis, Muscular
Dystrophy (MD), Cervical Spondylosis, Cervical Myelopathy and Chronic
Fatigue Syndrome (CFS). Other patients are labeled as “neurotic” because of the vague
complaints of headache and sensory abnormalities.
NOT
ALL patients have a classical picture of the deeply herniated tonsils.
Individuals
who suspect that they have ACM should be evaluated by a neurologist or
neurosurgeon with experience in the treatment of Arnold Chiari Malformation.
A
Good examination should not only include the physical abnormalities of the
motor, sensory and reflex systems but also the patient’s subjective report of
pain and dysesthesia (numbness). The best prognostic
tool for identifying ACM is high quality Nuclear
Magnetic Resonance (NMR/MRI).
TREATMENT:
Early
recognition and intervention by a neurosurgeon are therefore crucial in
ensuring a favorable neurological outcome.
There are many ways to treat ACM but they all require surgery. Currently there are over 20 different
practiced operations to either decompress or divert Cerebral Spinal Fluid (CSF)
pressure. The operations include but are
not limited to: decompressing the brainstem
by surgically removing part of some of the cervical vertebra and the lowest
part of the skull, shunt placement and reconstruction of a larger posterior
fossa. Some studies suggest that
patients with pronounced motor and sensory deficits have the worst prognosis
for recovery.
REFERENCES:
A Guide to Brain Anatomy
Retrieved
August 2001 from the World Wide Web
www.waiting.com/brainanatomy.html
Anencephaly Support
Foundation
Retrieved August 2001 from the World Wide Web
www.asfhelp.com/ASF_files/asf_home.htm
OR
www.asfhelp.com/ASF_files/ethics_files/Organ_Farms_article.htm
Bates, Sarah. Arnold Chiari patient and former nurse.
Personal
e-mail correspondence
The British United Provident
Association
Retrieved
August 2001 from the World Wide Web
www.hcdz.bupa.co.uk/fact__sheets/Mosby__factsheets/Hearing__Loss.html
Brum, G., McKane, L., Karp, G.
(1989). Biology: Exploring Life Second Edition. New
REFERENCES:
Children’s Hospital Boston:
Child Health A to Z, Neurological Service, Chiari
Malformation
Retrieved August 2001 from the World Wide Web
www.childrenshospital.org/cfapps/A2ZtopicDisplay.cfm?Topic=Chiari%20Malformation
Perspective
for Diagnosis and Treatment.
Deem. J., Miller, L.
(2000). Manual of Voice Therapy. Austin Texas: Pro-ed.
Guyton, Fallon. Are
symptoms in Chiari Malformation Gender Related?
Retrieved May 2001 from the World Wide Web
www.presenter.com/~chip/fallstudy.htm
Grigg, Kathleen. Arnold Chiari patient and moderator of the
World Arnold
Chiari Malformation Association.
Personal
e-mail correspondence
Graaff, K, Rhees, R. (1987). Schaum’s Outline of
Theory and Problems of Human
Anatomy and Physiology.
Retrieved August 2001 from the World Wide Web
www.nyneurosurgery.org/child/chiari/malformation.htm
Kiernan John. Anatomical
Foundations of Neuroscience
Retrieved August 2001 from the World Wide Web
www.publish.uwo.ca/~jkiernan/anfound.htm
REFERENCES:
MacKay,
Myelodysplasia. Myelodysplasic
Syndromes
Retrieved August 2001 from the World Wide Web
www.members.tripod.com/danil_hammoudi/lymph2/idzo.htm
National Institute of
Neurological Disorders and Stroke
Spina Bifida
Information Page
Retrieved August 2001 from the World Wide Web
www.ninds.nih.gov/health_and_medical/disorders/spina_bifida.htm
Nicolosi, L., Harryman, E., Kresheck, J. (1989).
Termnology of Communication
Disorders
Speech-Language-Hearing Third Edition.
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of Chiari Malformation: A morphomtric Study of
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Retrieved
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www.c3.hu/~mavideg/jns/1-5-pl.htm
Perkins,
W., Kent, R. (1986). Functional
Anatomy of Speech, Language, and
Hearing
A primer.
Dr. ML Grunnet.
Synopsis of Meningomyelocele of the
Spinal Cord
Medline
at National Library of Medicine
Retrieved
August 2001 from the World Wide Web
http://esynopsis.uchc.edu/S483.htm
Medterms
Retrieved
August 2001 from the World Wide Web
http://www.medterm.com/Script/Main/hp.asp
REFERENCES:
National Institute of
Neurological Disorders
Retrieved
August 2001 from the World Wide Web
http://www.ninds.nih.gov/health_and_medical/disorders
http://www.ncbi.nlm.nih.gov/pubmed/
then
type in number listed for each article listed below
PMID:
11082884 Episodes
of unilateral sympathetic hyperfunction, changes in
consciousness status and respiratory dysfunction in a girl with type II Chiari
malformation
9152746 Laryngealogic
management of infants with Chiari II syndrome
8617124 Esophageal dysphagia
as the sole symptom in type I Chiari malformation
2360371 Brain
stem dysfunction in Arnold Chiari II Syndrome
3625403 Management
of Chiari II complications in infants with myelomeningocele
7383257 Severe
respiratory and swallowing disturbances associated with Arnold Chiari
malformation
639601 Cricopharyngeal achalasia
associated with Arnold Chiari malformation in childhood
1584383 Neurogenic dysphagia
resulting from Chiari malformations
Retrieved August 2001 from the World Wide Web
www.teaching-biomed.man.ac.uk/resourses/wwwcal/cranial_nerves/page2.asp#Vagus
Syringomyelia Facts, Do You Have Any of These Symptoms?
Retrieved August 2001 from the World Wide Web
Tomblin, J., Morris, H.,
Pathology
Second Edition.
First
A.C. and S.M. Web Site!
Retrieved May 2001 from the World Wide Web
http://www.soft.net.uk/stregawarlock/syringom.htm
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www.teaching-biomed.man.ac.uk/student_projects/2001/mnbf8ao2/Vagus.htm
Watt, Ronnie. What are the Symptoms of Chiari?
Retrieved May 2001 from the World Wide Web
www.pressenter.com/~chip/symptms.htm
World ACM Association – Home
Retrieved
May 2001 from the World Wide Web
World
Retrieved May 2001 from the World Wide Web
www.pressenter.com/~wacma/mail.htm
Zemlin,W.
(1988). Speech and Hearing Science Anatomy and
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