Ataxia
in the Stroke Patient
Kelli Kulpa BSN, RN
Alverno College MSN Student
Neurosciences Department
Froedtert Hospital
Objectives
• Describe pathophysiology of cerebellum as it
relates to smooth muscle movements
• Describe how ischemia to cerebellum causes
ataxia in stroke patient
• Identify presence of ataxia in stroke patient
• Identify appropriate nursing interventions and
outcomes
TOPICS TO REVIEW
STROKE
CEREBELLUM
ATAXIA
NIH STROKE SCALE
CARE OF THE PATIENT WITH ATAXIA
Stroke
• “Syndrome of acute focal
neurologic deficit from a vascular
disorder that injures brain tissue”
Porth (2005, p. 1245)
• US leading cause of mortality &
morbidity
• About 700,000 Americans afflicted
with stroke
• Many survivors left with some
degree of deficit
(Porth, 2005)
Image from Microsoft Clipart
Risk Factors for Stroke
• Controllable
•
•
•
•
•
•
•
•
Hypertension (HTN)
Atrial Fibrillation
High Cholesterol
Diabetes
Tobacco Use & Smoking
Alcohol Use
Physical Inactivity
Obesity
(National Stoke Association, 2009)
Image from Microsoft Clipart
• Uncontrollable
•
•
•
•
•
•
•
Age
Race
Gender
Family History
Previous Stroke or TIA
Fibromuscular Dysplasia
Patent Foramen Ovale
Uncontrollable Risk Factor
• AGE:
• Risk of stroke increases
with age
• After age 55, risk
doubles for every
decade that passes
• Increased prevalence of
controllable risk factors
as age increases
• Hypertension
• High Cholesterol
• Diabetes
(National Stoke Association, 2009)
Image from Microsoft Clipart
• RACE: AFRICANAMERICAN
• Most impacted race in
US
• Twice as likely to die
from stroke than
Caucasians
• Occur earlier in life
• Reasons not fully
understood, but have a
higher rate of risk factors
• ex: 41% have HTN
Uncontrollable Risk Factor
• GENDER: WOMEN
• 55,000 more women than men experience stroke each
year
• Unique risk factors:
• Oral Contraceptives
• Pregnancy
• Hormone replacement therapy
• Post-menopausal with thick waist and high triglyceride
levels
• Suffer more migraines, increase risk 3-6 times
(National Stoke Association, 2009)
Image from Microsoft Clipart
Uncontrollable Risk Factor
• FAMILY HISTORY
• Evidence suggests genes influence vulnerability to HTN &
stroke
• A region on:
• Chromosome 13 in Caucasians
• Chromosome 19 in African-Americans
(Morrison, Brown, Kardia, Turner, &
Boerwinkle, 2003)
• Carotid intimalmedial wall thickness (IMT)
• Surrogate measure of subclinical atherosclerosis
• Strong predictor of future ischemic strokes
• Homozygous for 6A genotype
• Genetically predisposed to produce less stromelysin 1
• High carotid artery wall thickness & greater risk of stroke
Image from Microsoft Clipart
(Humphries & Morgan,
2004)
Controllable Risk Factor &
Inflammation
• Inflammation can influence the development
of atherosclerosis
• Causes endothelial dysfunction
• One of the earliest manifestations of atherosclerosis
• Inflammatory markers associated:
• Coronary disease development
• Disease severity
• Occurrence of coronary events
• Progression of atherosclerosis may be associated
with high concentrations of inflammatory markers
(Humphries & Morgan, 2004)
TEST YOUR KNOWLEDGE
• Select the controllable risk factors for stroke
(Multiple answers)
Hypertension
GOOD JOB!
SORRY!
Cannot
Previous
control
Stroke
if you
have a history of stroke
OPPS!
Age
Cannot control age
Hyperlipidemia
GREAT!
TEST YOUR KNOWLEDGE
• Men are at higher risk of stroke
Sorry!
Women are at higherTRUE
risk of stroke & also have
increased mortality.
Yes!
Women are at higher risk of stroke & also have
FALSE
increased mortality.
Types of Stroke
• ISCHEMIC
• Interruption of blood flow in
a cerebral vessel
• Most common type
• Account for 70-80% of strokes
• HEMORRHAGIC
• Bleeding into the brain tissue,
from blood vessel rupture
• Caused by:
• HTN
• Aneurysms
• AVM
• Head injury
• Much higher fatality rate
•
37-38% of occurrence results in death
(American Heart Association, 2010)
(Porth, 2005)
Image from Microsoft Clipart
Cell Ischemia
• Reduced or absent blood flow deprives cell of
needed nutrients
• Effects occur quickly
• No stored glucose in brain
• Incapable of anaerobic metabolism
(Porth, 2005)
Neuronal Injury: Excitotoxicity
• Ischemia depletes neuronal energy stores causing energy
dependent membrane ion pumps to fail
• Results in increased extracellular glutamate concentration
• Release of excitotoxic glutamate & aspartate open up calcium
channels
• Influx of calcium, sodium and chloride
• Intracellular calcium responsible for activation of a series of destructive
enzymes
• Out flux of potassium
• Resulting in irreversible neuronal damage
• Results in release of cytokines and other mediators
(Porth, 2005)
Inflammation Following Ischemia
• Rapid production of inflammatory mediators
• White blood cell (WBC) recruitment to ischemic area as early as 30 minutes
• Capillary endothelium produces adhesive proteins causing WBCs to adhere
to capillary lining
• WBCs move into injured tissue
• Phagocytize injured cells
• Extent of inflammation can be determined by C-reactive protein levels
(Porth, 2005)
Image used with permission from
http://images.wellcome.ac.uk/
TEST YOUR KNOWLEDGE
• Neural cell ischemia is caused from:
Try again
If the cell is not getting
Too much energy available
adequate blood flow, there
to the cell
is not enough energy
available.
Energy
GOOD
dependent
JOB!
No energy
membrane
is getting
ionto the
pumps
cell. fail
Try again
Lack of phosphorus
Phosphorus is not directly
available
related to this process
Try again
Decreased levels
There are increased levels
of glutamate
of glutamate.
Cerebellum
• Stores learned sequences of
movements
• Fine tuning & coordination
of movement produced
elsewhere in brain
• Integrates all information to
produce fluid movements
(Dubuc, 2002)
Image used with permission from
http://thebrain.mcgill.ca/flash/i/i_06/i_06_cr/i_0
6_cr_mou/i_06_cr_mou.html#3
Movement
• Motor cortex:
• Sends signals to cerebellum
• Communicates movement to
make
• Cerebellum:
• Makes continuous
adjustments
• Final result:
Hover over the highlighted
words for definition
Cerebellum
• Smooth movement, key with
delicate maneuvers
(Porth, 2005)
Image used with permission from
http://thebrain.mcgill.ca/flash/i/i_06/i_06_
cr/i_06_cr_mou/i_06_cr_mou.html
Cerebellum Involvement
• Receives proprioceptor
input from vestibular
system
• Feedback from muscles,
tendons, & joints
• Indirect signals from
somesthetic, visual, &
auditory systems to
provide background info
for ongoing movement
(Porth, 2005)
(McGill University, 2002)
• Can continuously assess
status of each body part
• Position
• Rate of movement
• Forces, such as gravity,
opposing it
Dampening Muscle Movement
• All body movements are pendular
• Intact cerebellum analyzes proprioceptive
information to predict:
• Future position of moving parts
• Speed of movement
• Projected time course of movement
• As movement approaches target, Cerebellum
will:
• Inhibit agonist muscles
• Excite antagonist muscles
(Porth, 2005)
(Porth, 2005)
Image from Microsoft Clipart
Type of Movement
“Require a burst of energy from an agonist
muscle group; the movement is programmed
from the start, so the movement proceeds
from start to finish without modification”
Simple Movement
Click for Explanation
Porth (2005, p. 1194)
Image from Microsoft Clipart
Self-terminating Movement: require smooth
muscle sequence of coordinated agonist &
antagonist movements programmed by higher
Complex
brain centers
to start, Movement
then are modified as
the movement proceeds
Click for Explanation
TEST YOUR KNOWLEDGE
• Proprioreceptor input is:
Meaningfulness of
Try again;
integrated sensory
This is part of the
information from various
somesthetic system.
sensory systems
Any sensory nerve ending
responding to stimuli from
GOOD JOB!
within body related to
movement & spatial position
The inner ear
OPPS!
structures that
are
Vestibular
associated
apparatus,
with balance
try
and position
again. sense
Concerning perceptions of
Try again;
‘where’ the stimulus is in
This is part of the
space and in relation to
somesthetic system.
body parts
TEST YOUR KNOWLEDGE
• As movement approaches a target, the
cerebellum will:
Yes!
Inhibit
Movement
agonist muscles
is pendulous,
& Excite
soantagonist
muscles have
muscles
to be stopped.
Opps!
Excite agonist muscles & Inhibit antagonist muscles
Think this through again. Movement is pendulous.
Ataxia
• People with ataxia experience
• Failure of muscle control in arms and legs
• Results in:
• Lack of balance & coordination
• Disturbance in gait
(National Institute Of Neurological
Disorders And Stroke, 2010)
Image from Microsoft Clipart
Acquired (non-genetic) Ataxia
• Conditions that can cause acquired ataxia
• Stroke
• Multiple Sclerosis
• Tumors
• Alcoholism
• Peripheral neuropathy
• Metabolic disorders
• Vitamin deficiencies
(National Institute Of Neurological Disorders And Stroke, 2010)
Image from Microsoft Clipart
Ataxia after Stroke
• Right side of cerebellum controls coordination on
right side of body, left side controls left
• When nerve cells are lost or damaged:
• Provide less control to muscles
• Resulting in: loss of coordination
• During a stroke:
• Blood supply is interrupted or severely reduced
• Deprivation of oxygen and nutrients to brain tissue
• Brain cells begin to die
(Mayo Clinic Staff, 2009)
Image from Microsoft Clipart
Recent Findings
• 15% of all cerebral strokes involve
the cerebellum
(Timmann et al., 2009)
• Anterior lobe of cerebellum is
involved in motor control
• Concluded from a study containing 34
patients with cerebellar infarcts
(Schmahmann, Macmore, & Vangel, 2009)
Image from Microsoft Clipart
Cerebellar Ataxia
• Decomposition of movement
• Each component of the movement
occurs separately instead of being
blended into a smooth action
(Porth, 2005)
How does alcohol relate?
Select the beer for the answer!
“Ethanol specifically affects
cerebellar function, persons who are
inebriated often walk with a
staggering and unsteady gait”
Porth (2005, p. 1213)
(Porth, 2005)
Image from Microsoft Clipart
Ataxia
• Rapid alternating
movements are performed
slowly and jerky
• Such as pronation-supinationpronation of hands
• Touching a target:
• Movements broken down
into small steps
• Each movement goes too far,
then overcompensated
• DYSMETRIA
(Porth, 2005)
Image from Microsoft Clipart
SELECT THE TARGET TO SEE AN
ANIMATION OF DYSMETRIA
Clinical Pearl
• Read the CT or MRI
reports to identify
where the infarct is
located in the brain. If
the cerebellum is
involved, chances are
ATAXIA will be exhibited
in the patient
Image from Microsoft Clipart
TEST YOUR KNOWLEDGE
• Ataxia is:
Weakness
Try again
LackGOOD
of coordination
JOB!
Impaired
OPPS!
speech
No need
Tryto
again
pay taxes
TEST YOUR KNOWLEDGE
• What part of the brain was infarcted if the
patient has ataxia?
AWESOME!
Cerebellum
Think again,
motor cortex is involved in
Motor Cortex
movement, but not directly
related to ataxia.
Try again;
Parietal Lobe
not related to movement
Almost there…
Cerebrum
look closer at the options.
TEST YOUR KNOWLEDGE
• Ataxia in stroke is acquired ataxia.
Yes!
True
Acquired ataxia is non-genetic.
Opps!
Ataxia after a stroke is not
False
a genetic cause of ataxia.
Genetic ataxia is caused from mutations in genes.
National Institute of Health Stroke
Scale (NIHSS)
• Stroke scale functions:
• Document and communicate
• Baseline deficits
• Changes over time
• First used in 1989
• Administered in mean time of 6.6 minutes
• Interrater and intrarater agreement is good
(Jensen & Lyden, 2006)
Image from Microsoft Clipart
National Institute of Health Stroke
Scale (NIHSS)
• Strongly predicts the likelihood of recovery
after stroke
• Total score
• > 16 high probability of death or severe disability
• <6 predicts a good recovery
(Duncan et al., 2005)
Image from Microsoft Clipart
National Institute of Health Stroke
Scale (NIHSS)
• 15 Item Clinical Deficit Scale
• Assess:
•
•
•
•
•
•
•
•
•
(Jensen & Lyden, 2006)
Image from Microsoft Clipart
Level of Consciousness
Gaze
Vision
Facial Palsy
Arm & Leg Strength
Limb Ataxia
Neglect
Dysarthria
Aphasia
REMEMBER:
MUST BE ASSESSED
IN ORDER LISTED
NIHSS
Limb Ataxia
“A few items consistently show poor
agreement, notably ataxia,
dysarthria, and facial weakness”
Jensen & Lyden (2006, p. 2)
YOU’RE NOT THE ONLY ONE
WHO MAY MAKE AN ERROR
SCORING ATAXIA!!!
NIHSS
Limb Ataxia
• Assesses evidence of a unilateral cerebellar
lesion
• Assesses incoordination from weakness
• Test with eyes open, in intact visual field
• Test on bilateral extremities
(NIH Stroke Scale International, 2001)
(National Institute Of Neurological Disorders And Stroke, 2001)
Evaluating Limb Ataxia
• Scored if present out of proportion to
weakness
• Two instances when ataxia would not be
assessed
• Absent in patients who do not understand or are
paralyzed
• Untestable (UN) if amputation or joint fusion
present
(NIH Stroke Scale International, 2001)
(National Institute Of Neurological Disorders And Stroke, 2001)
Finger-Nose-Finger Test
• Ask patient to touch your
index finger with his index
finger and then back to his
nose
• Repeat enough times to fully
assess for ataxia, moving
your index finger each time
to make a new target
• Then repeat using other
extremity
(NIH Stroke Scale International, 2001)
Image from Microsoft Clipart
Click on picture of
face to view
example of fingernose-finger test
with ataxia present
Heel-Shin Test
• Ask patient to move right
heel up and down the left
shin
• Repeat enough times fully
assess for ataxia
• Then repeat using other
extremity
(NIH Stroke Scale International, 2001)
Image from Microsoft Clipart
Click on picture to
view example of
heel-shin test with
ataxia present
Limb Ataxia
• SCALE DEFINITION
• 0
• 1
• 2
• UN
Absent (Not present or paralyzed)
Present in 1 limb
(an arm or a leg)
Present in 2 limbs
(both arms, both legs,
or arm and leg on same
side of body)
Amputation or joint fusion (explain)
• The link below will take you to the National Institute of Health Stroke Scale
Training Video
• Assessment #7 Limb Ataxia
http://www.youtube.com/watch?v=8AXtl3QPH7Y&feature=related
(NIH Stroke Scale International, 2001)
Video used with permission from
NIHSS English Training Campus
TEST YOUR KNOWLEDGE
• Ataxia occurs because of muscle weakness
after a stroke.
False:
True
Ataxia is incoordination, not weakness!
Great job!
False
Ataxia is incoordination, not weakness!
TEST YOUR KNOWLEDGE
• Ataxia needs to be assessed prior to weakness
in the NIH Stroke Scale.
Think about the order of the exam.
True
Ataxia is assessed after weakness!
Great job!
False
Ataxia is assessed after weakness!
TEST YOUR KNOWLEDGE
• If the patient has weakness in the right arm
and is unable to lift the arm off the bed,
would ataxia be present?
No, ataxia is not present because the patient is
unable to perform
Yes the test.
The score would be absent or 0 due to paralysis.
Great job!
Ataxia is not present because the patient is
No
unable to perform the test.
The score would be absent due to paralysis.
TEST YOUR KNOWLEDGE
• The patient exhibits some weakness in the right arm and is able to
perform the finger-nose-finger test. The patient misses the
assessors finger. The patient completes test on left arm without
difficulty. What score would be given for the upper extremity test?
Try again!
0
Ataxia is present in R arm.
GREAT1 JOB!
Try again!
Ataxia is only 2present in the
R arm.
Try again!
Only score UN
UNif amputation
or joint fusion present.
Treatment
• There is no current cure of ataxia following a
cerebellar stroke
• Physical & Occupational Therapy
• Strengthen muscles
• Assistive devices
• Assist in walking and other activities of daily living
(ADLs)
(National Institute Of Neurological Disorders And
Stroke, 2010)
Image from Microsoft Clipart
Nurse Sensitive Outcomes
• Impaired Mobility
• Mobilize early to prevent complications
• Active & Passive range of motion (ROM)
• Participate in self-care & activities frequently
• Teach safe use of assistive devices
• Educate & Facilitate adaptation of home/work
environment for maximal independence
• Teach safety precautions
• Expected outcomes:
• Optimal independence with ADLs & mobility
• Maintain safety precautions
(Bader & Littlejohns, 2004)
Nurse Sensitive Outcomes
Self-Care Deficit
•
•
•
•
Evaluate ability to perform ADLs
Consult occupational therapy (OT)
Assess for risk of falls
Expected outcomes:
• Functional abilities recognized & advanced
(Bader & Littlejohns, 2004)
Nurse Sensitive Outcomes
Safety
• Identify Fall Risk
• Implement fall prevention strategies
• Universal Fall Risk Interventions
• Fall Precautions due to activity impairment
• Expected outcome:
• Effective in decreasing vulnerability to falls and
related injury
(Summers et al., 2009)
Nurse Sensitive Outcomes
Anticipatory grieving related to loss of functional
abilities
• Facilitate discussions to allow patient/family to
voice concerns
• Neuropsychiatry consult to evaluate cognitive vs.
depressive issues
• Rehabilitation consult to evaluate needs
• Support Groups
• Expected outcomes:
• Supported & given resources to assist with coping
(Bader & Littlejohns, 2004)
Coping
• Challenges:
• Loss of independence
• May feel alone
• Lead to depression & anxiety
• Therapy or counseling may lessen sense
of isolation and help cope
• Can lead to increased stress on the
patient
• Habitual Stress
• The physiologic & behavioral changes induced
by generalized stress response can threaten
homeostasis
(Porth, 2005)
(Mayo Clinic Staff, 2009)
Generalized Stress Response
• Stroke is a life changing event people do not have
time to prepare for
• Stress can impact controllable risk factors for stroke
•
•
•
•
•
•
Hypertension
High cholesterol
Tobacco use
Alcohol use
Physical Inactivity
Obesity
Generalized Stress Response (GSR)
• Sympathetic Nervous System (SNS)
• “Fight or Flight Response”
•
•
•
•
Increased heart rate and strength of contraction
Increased metabolic rate, stored fat released into circulation
Bronchodilation in lungs
Vasoconstriction of:
• Skin
• Gut
 Decreased motility
 Less insulin secreted
• Kidneys
• Pupils Dilate
(Porth, 2005)
Renin-Angiotensin-Aldosterone Pathway
Decreased blood flow to
kidneys
as response to SNS
stimulation
Aldosterone released
from adrenal cortex
turns on Na/K ATPase
in kidneys
(Porth, 2005)
Renin released
Activates angiotensinogen
Converted into Angiotensin
II
Forms Angiotensin I
a strong vasoconstrictor
leads to increased blood volume and
increased blood pressure, should
increased blood flow to the kidneys
Hormone Involvement in GSR
• Corticotropin-releasing Factor (CRF)
• Released by the hypothalamus
• Stimulates ACTH release
• Adrenocorticotropic hormone (ACTH)
• Released from the anterior pituitary gland
• Stimulates synthesis and release of cortisol
• Cortisol
• Released from adrenal cortex
• Affects many systems and processing in the body
(Porth, 2005)
Effects of Cortisol
•
•
•
Cardiovascular
• arterioles more responsive to sns
• increased contractility
Liver
• stored glucose released into blood
Pancreas
• decreased insulin release
•
Adipose tissue
• lipids released from periphery,
redeposited in trunk
•
Skeletal
• decreased bone deposition
(Porth, 2005)
• Renal
• calcium lost in urine
• Na+/K+ pump reabsorbs Na+ and
H2O into blood, secretes K+ into
urine
• Muscular
•
actin and myosin break down
• Immune
• production of prostaglandins
blocked
• thymus atrophies
• neutrophils can't leave blood
• monocytes and macrophages less
active
TEST YOUR KNOWLEDGE
• Identify the most appropriate nursing diagnosis in terms of special
needs when ataxia is present.
Try again;
Ataxia does not affect
Impaired gas exchange
breathing in the stroke
patient.
Try again;
Ataxia does not affect
Ineffective breathing pattern
breathing in the stroke
patient.
Great job!
Impaired
Very important
physical to
mobility
also
consider fall risk!
Try again!
Impaired
Ataxia affects
tissue
movement,
perfusion
not tissue perfusion.
TEST YOUR KNOWLEDGE
• Treatment for ataxia in the stroke patient is:
Try again;
Used for stroke
TPA treatment,
but not for treating ataxia.
Try again;
Heparin
Not used for treating ataxia.
Try again;
Movements are impaired
Muscle Relaxers
because of communication
error in the brain.
GREAT!
Currently no treatment
No Treatment Available
available. PT & OT to help
with function.
Case Study
• A 67 year old male with a history of afib and
prior stroke (with no deficits) was admitted
from home with acute onset of nausea,
generalized weakness, ataxia, and left sided
weakness. Initial MRI noted a large acute
ischemic infarct within the left cerebellum and
smaller infarcted areas within the cerebellar
vermis and right cerebellum with occlusion of
the right internal carotid artery.
Case Study
• What is the anticipated medical diagnosis of
the patient?
Try again;
Stroke
Be more specific
Cerebellar
GREAT!!!
Stroke
Try again;
Weakness
Be more specific.
Case Study
• When tested for ataxia, it was present on the
bilateral upper extremities. What score would
be given according to the NIHSS?
Opps!
Ataxia is present,
0 therefore,
0 cannot be the score.
Try again;
Ataxia is present
1
in both
upper extremities.
GREAT!
Score 2 if present in bilateral
upper or lower
2 extremities,
or an arm and leg on the
same side of the body.
Case Study
• What appropriate nursing diagnosis would be
given to this patient related to the presences
of ataxia?
Sorry,
This would be appropriate, but
Impair tissue perfusion
not specific to the symptom of
ataxia.
Great!
Think safety with patients
experiencing ataxia!
ThisRisk
patient
for injury:
has left
falls
sided
weakness, plus BUE ataxia. This
could make using mobility
devices harder.
Try again,
This could be present in the
Impaired memory
patient, but does not relate to
ataxia.
The End
• With the completion of the tutorial, you are
now able to:
• Describe pathophysiology of cerebellum as it
relates to smooth muscle movements
• Describe how ischemia to cerebellum causes
ataxia in stroke patient
• Identify presence of ataxia in stroke patient
• Identify appropriate nursing interventions and
outcomes
References
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Retrieved February 10, 2010, from http://www.guideline.gov/
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Bader, M., & Littlejohns, L. R. (2004). AANN core curriculum for neuroscience nursing (4th ed.). St. Louis, MO: Saunders.
Duncan, P. W., Zorowitz, R., Bates, B., Choi, J. Y., Glasberg, J. J., Graham, G. D.,...Reker, D. (2005). Management of adult stroke
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Humphries, S., & Morgan, L. (2004). Genetic risk factors for stroke and carotid atherosclerosis: insights into pathophysiology from
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http://www.stroke.org/site/DocServer/SCU_-_Jan-Feb_2006.pdf?docID=5166
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nic.com/health/ataxia/DS00910/DSECTION%3Dcauses
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Morrison, A. C., Brown, A., Kardia, S. L., Turner, S. T., & Boerwinkle, E. (2003). Evaluating the context-dependent effect of family
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Mosby (2002). Mosby's pocket dictionary of medicine, nursing, & allied health (4th ed.). St. Louis, MO: Mosby, Inc.
National Institute Of Neurological Disorders And Stroke. (2010). NINDS ataxias and cerebellar or spinocerebellar degeneration information
page. Retrieved from http://www.ninds.nih.gov/disorders/ataxia/ataxia.htm
National Institute Of Neurological Disorders And Stroke. (2001). NIH stroke scale. Retrieved from http://stroke.nih.gov
National Stoke Association. (2009). Stroke risk factors am I at risk for a stroke? Retrieved from
http://www.stroke.org/site/PageServer?pagename=RISK
NIH Stroke Scale International. (2001). NIH stroke scale (NIHSS) in English. Retrieved from http://www.nihstrokescale.org/
NIHSS English Training Campus. (21). 2 9 7 limb ataxia. Retrieved April 1, 2010, from
http://www.youtube.com/watch?v=8AXtl3QPH7Y&feature=related
Porth, C. M. (2005). Pathophysiology: concepts of altered health states (7th ed.) Lippincott.
Schmahmann, J. D., Macmore, J., & Vangel, M. (2009). Cerebellar stroke without motor deficit: clinical evidence for motor and nonmotor domains within the human cerebellum. Neuroscience, 162, 852-861.
Shah, S. (n.d.). Pathophysiology of stroke. Retrieved March 12, 2010, from http://www.ferne.org/
Summers, D., Leonard, A., Wentworth, D., Saver, J. L., Simpson, J., Spilker, J. A.,...Mitchell, P. H. (2009). Comprehensive overview
of nursing and interdisciplinary care of the acute ischemic stroke patient. A scientific statement from the American
Heart Association. Stroke, 40. doi:10.1161/STROKEAHA.109.192362
Timmann, D., Konczak, J., Ilg, W., Donchin, O., Hermsdorfer, J., Gizewski, E. R., Schoch, B. (2009). Review: current advances in
lesion-symptom mapping of the human cerebellum. Neuroscience, 162, 836-851.
Wellcome Images. (n.d.). Wellcome Images. Retrieved February 12, 2010, from http://images.wellcome.ac.uk/