Diagnosis of Vertebrobasilar Insufficiency Using Transcranial

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Sean Steward
February 20, 2013
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Vertebrobasilar Insufficiency
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Signs and Symptoms
Risk Factors
Tests
Transcranial Doppler Ultrasound
Case Study
QA statistics of TCD
Conclusion
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Vertebrobasilar insufficiency (VBI) is a posterior
circulation transient ischemic attack (TIA) caused by
intermittent vertebral artery occlusion that is induced
by a head rotation or extension
VBI also may result from large vessel atherosclerotic
disease, dissection, cervical compressive lesions, and
subclavian steal phenomenon
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Loss of vision in part or all of both eyes
Double vision
Vertigo (spinning sensation)
Numbness or tingling
Nausea and vomiting
Slurred speech
Loss of coordination, dizziness or confusion
Trouble swallowing
A drop attack — sudden generalized weakness
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Ucdavis.edu
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Smoking
Hypertension
Hyperlipidemia
Older age
Gender: men have a higher risk before age 75;
women have a high risk after 75
Family history
Genetic factors
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Ucdavis.edu
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Magnetic Resonance Angiography (MRA)
Standard angiography (X-ray study using injected dye)
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Both are used to identify vertebrobasilar artery disease
Digital Subtraction Cerebral Angiography (DSA) is considered the
“gold standard” diagnostic test
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Mild sedative is used
Electrocardiogram is attached
Catheter placed starting in the groin
Contrast material
DSA uses a computer to "subtract" or take out the bones and tissues in
the area viewed, so that only the blood vessels filled with the contrast
dye are seen
Ucdavis.edu
Nlm.nih.gov
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Typically use a 2 MHz probe
Angle of insonation is zero
degrees
(3) most common windows
utilized:
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Transforamenal (A)
Transtemporal (B)
Transorbital (C)
Standard method of
quantifying velocity is time
averaged mean velocity
(TAMV)
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A
McPharlin & Rumwell
B
C
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Accurate vessel identification
Appropriate sample volume and depth
Direction and velocity of blood flow
 McPharlin & Rumwell
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50 year old Caucasian male
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Presented with one year of positional vertigo and
ataxic gait when extending his neck
 Positional vertigo is a sudden sensation of spinning
with head movements
 Ataxic gait is an unsteady, uncoordinated walk
CT and MRI were WNL
 TCD performed
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 nlm.nih.gov
 thefreedictionary.com
 ncbi.nlm.nih.gov
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TCD monitoring of the bilateral PCA (Posterior
Cerebral Artery) mean flow velocities were
monitored in different head positions using a
head frame to avoid any changes in the angle
of insonation
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ncbi.nlm.nih.gov
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Transforamenal window was used to image the
vertebral arteries and basilar arteries
Transtemporal window was used to evaluate
the posterior cerebral arteries
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In an upright position the mean velocities for the
right and left PCA’s were 18cm/sec and 19cm/sec
 ncbi.nlm.nih.gov
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After the TCD imaging was performed:
An electronystagmography (ENG) was performed
which was negative
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Electronystagmography (ENG) is used to evaluate people
with vertigo (a false sense of spinning or motion that can
cause dizziness) and certain other disorders that affect
hearing and vision
An MRI of his cervical spine was done to rule out
myelopathy
Myelopathy is a term used to describe symptoms related
to spinal cord compression
 Cervical (neck) myelopathy is most common
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 hopkinsmedicine.org
 piedmonthospital.org
 ncbi.nlm.nih.gov
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Review:
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(2) MRI’s (Both negative)
CT (Negative)
ENG (Negative)
ENT (Ear nose and throat work up – Negative)
TCD (Showed positive results…thank you very
much)
Patient refused spinal surgery and is being treated
conservatively
 ncbi.nlm.nih.gov
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According to a series that was done in 1992 that
compared TCD with DSA (Gold Standard) in 20
patients the results are as follows for TCD:
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Sensitivity – 87%
Specificity – 80%
Positive Predictive Value – 93%
Negative Predictive Value – 67%
The results proved that TCD is a useful screening
method in patients with VBI to detect large vessel
disease of the intracranial vertebrobasilar system
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ncbi.nlm.nih.gov
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VBI is a very difficult disease to diagnose
TCD should be the new “Gold Standard”
diagnostic test for evaluating VBI’s
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It’s noninvasive
 No sedative, catheter, contrast dye, ECG
Relatively inexpensive test
 Can go bedside if needed
 Proven QA numbers
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Alnami, I., Siddiqui, M. & Saqqur, M. (2012, November).Case Reports
in Medicine. TheDiagnosis of Vertebrobasilar Insufficiency Using
Transcranial Doppler Ultrasound.Retrieved from:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3509548/
Ataxic gait (n.d.) The free dictionary. Retrieved from: http://medicaldictionary.thefreedictionary.com/ataxic+gait
Benign positional vertigo (n.d.).Medline Plus.Retrieved from:
http://www.nlm.nih.gov/medlineplus/ency/article/001420.htm
Cerebral angiography (n.d.).Medline Plus.Retrieved from:
http://www.nlm.nih.gov/medlineplus/ency/article/003799.htm
Electronystagmography (ENG) (n.d.) John Hopkins Medicine.
Retrieved
from:http://www.hopkinsmedicine.org/healthlibrary/test_procedur
es/neurological/electronystagmography_eng_92,P07659/
McPharlin, M., & Rumwell, C. (2009). Vascular Technology: An
Illustrated Review. Pasadena, CA:Davies Publishing, Inc.
Myelopathy (n.d.) Piedmont Healthcare. Retrieved
from:http://www.piedmonthospital.org/SpineCenter/Myelopathyctr
.aspx
UCDavis Health System. Vertebrobasilar insufficiency.
Retrieved
from:http://www.ucdmc.ucdavis.edu/vascular/diseases/vertebroba
silar.html
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