CORE II VASCULAR

Home > Preview

The flashcards below were created by user jrw10 on FreezingBlue Flashcards.


  1. The brain is ___% of a person's body weight.
    The brain receives ___% of cardiac output.
    The brain consumes ___% of the body's oxygen supply.
    • 2%
    • 15%
    • 20%
  2. CCA bifurcates at ___ or _______ into the ICA and ECA.
    C4 or upper border of the thyroid
  3. ________ is the first branch off of the ICA.
    Ophthalmic A
  4. The Ophthalmic A then trifurcates into _______, _______, and _______.
    • Supraorbital A
    • Frontal A
    • Nasal A
  5. PCoA connects into the ____ from the ____.
    • ICA 
    • PCA
  6. Intimal Thickening:
    • Process that goes on with age.
    • Realize that small particles of plaque are deposited within the intima that causes thickening.
  7. Fibromuscular Hyperplasia:
    • Can be seen after a CEA. 
    • Media accumulates smooth muscle cells to replace the intima that was stripped away during a CEA. 
    • Also referred to as: Myointimal Hyperplasia.
  8. Fibromuscular Dysplasia:
    • Media has abnormal growth of smooth muscle cells.
    • Found more in older women and Asian descent.
    • Looks like a "string of pearls".
  9. Ulcers:
    • Can cause blood clots to form: 
    • Embolus
    • Hemorrhaging - Bleeding of capillaries can rupture through the lipid core, more thrombus can now develop on the cap and decrease lumen size. 
    • Complex lesions
  10. Common Causes of Stroke:
    • Atherosclerosis
    • Embolis
    • Hypertension
    • Dissection
    • Prethrombotic states - clotting factors
    • Vasospasm - subarachnoid hemorrhage
  11. Transient Ischemic Attack (TIA):
    • Lasts less than 24 hours.
    • Usually only lasts a few minutes.
    • Most people will experience a full blown CVA, if they experience a TIA.
    • Symptomatic.
  12. Reversible Ischemic Neurological Deficient (RIND):
    • Lasts longer than 24 hours.
    • Neurological deficit resolves within 3 weeks.
    • Symptomatic.
  13. Cerebrovascular Accident (CVA):
    • Lasts greater than 24 hours.
    • Permanent neurological damage, (never be 100%).
    • 3rd leading cause of death.
    • Symptomatic.
  14. Anterior Circulation: ICA, MCA, & ACA
    • Unilateral - parethesia, paresis, paralysis
    • Aphasias, arm paralysis, or paresis. (Usually means disease in MCA.)
    • Leg paralysis, incontinence. (Usually means disease in ACA).
  15. Posterior Circulation or Vertebrovasilar: Vertebrals, Basilar,& PCA
    • Bilateral - paralysis
    • Double vision, vertigo, ataxia, drop attacks.
    • Coma or dyslexia. (Usually means disease in PCA).
  16. Non-localized Symptoms:
    Dizziness, syncope, severe headache.
  17. ICA Stenosis Criterias:
    • Normal   <4kHz   <120cm/s
    • 1-15%   <4kHz   <120cm/s
    • 16-49%  <4kHz   <120cm/s
    • 50-79%  <4kHz   >120cm/s
    • 80-99%   >4kHz   >120cm/s
    • Occlusion             ----------
  18. ECA Stenosis Criteria:
    >50%     >4kHz     >200cm/s
  19. Lacunar Strokes:
    Risk of stroke and death is higher in patients with widespread Leukoaraiosis.

    Leukoaraiosis - scattered loss of white matter in the brain. Associated with strokes caused by blockages in small arteries deep in the brain.
  20. Poiseuille's Law:
    • Flow
    • Flow rate occurs primarily because of energy gradients, but observed as pressure gradient. (Differences in pressures).
    • An energy gradient must exist for flow to occur.
  21. Poiseuille's Law explains the interrelationship among ______, ______, & ______.
    • Pressure
    • Viscosity
    • Flow
  22. Diameter Reduction:
    A/B x 100 = Y

    Y is the size of the remaining lumen

    100 - Y = YS 

    YS is the size of the stenosis
  23. Area Reduction:
    (A/B)² x 100 = Y

    Y is the size of the remaining lumen

    100 - Y = YS

    YS is the size of the stenosis
  24. 30% Diameter reduction --> 
    50% Diameter reduction -->
    75% Diameter reduction -->
    • 50% Area reduction
    • 75% Area reduction
    • 90% Area reduction
  25. Carotid Stenosis Criteria Chart:

    Diameter Reduction    PSV   EDV   ICA/CCA Ratio
    • Normal      <125cm/s       <40cm/s      <1.8/<2.4
    • 1-15%       <125cm/s       <40cm/s  <1.8/<2.4
    • 16-49%     <125cm/s       <40cm/s       <1.8/<2.4
    • 50-79%    >125cm/s      >40cm/s     >1.8/>2.4
    • 80-99%    >250cm/s    >140cm/s    >3.7/>5.5
    • Occlusion      -----       ------          ------
  26. Why do we calculate ICA and CCA ratios?
    1.
    2.
    3.
    4.
    5.
    6.
    • 1. Presence of tandem lesions.
    • 2. Contralateral high grade stenosis.
    • 3. Discrepancy between visual assessment of the plaque and ICA PSV.
    • 4. Elevated CCA velocities.
    • 5. Hyperdynamic cardiac states.
    • 6. Person may have poor cardiac output, therefore have a decreased CCA velocity.
  27. ICA/CCA Ratio Example:

    PSV for ICA is 90cm/s
    PSV for DIST CCA is 125cm/s
    Ratio:
    EDV for ICA is 40cm/s
    EDV for DIST ICA is 60cm/s
    Ratio:
    PSV Ratio: 90cm/s / 125cm/s = 0.72

    EDV Ratio: 40cm/s / 60cm/s = 0.66
  28. ICA/CCA Ratio Example:

    PSV for DIST CCA is 175cm/s
    PSV for ICA is 130cm/s
    Ratio:
    EDV for ICA is 40cm/s
    EDV for DIST CCA 80cm/s
    Ratio:
    PSV Ratio: 130cm/s / 175cm/s = 0.74

    EDV Ratio: 40cm/s / 80cm/s = 0.50
  29. 3 Trials performed on the efficacy of CEA:

    1. NASCET
    2. ACAS
    3. ECST
    • 1. North American Symptomatic Carotid Endarterectomy Trial
    • 2. Asymptomatic Carotid Arteriosclerosis Study
    • 3. European Carotid Surgery Trial
  30. Subclavian Steal:
    • Occlusion seen in proximal portion of Subclv. A will cause retrograde flow within the Vert. A.
    • Stenosis seen in proximal portion of Subclv. A will cause to-fro flow within the Vert. A.
    • Usually asymptomatic.

    • If symptomatic:
    • Difference in BP >20 mmHg.
    • Verebrobasilar symptoms.
    • Monophasic waveform in Subclv. A
    • Retrograde or To-fro Flow.
  31. The ____ is the dominant out of the MCA and ACA.
    MCA
  32. If you have a MCA occlusion you will notice it in your ____ or ____.
    • ICA or CCA
    • (Resistive Spectra Waveform)
  33. Dolichocarotid Arteries:
    (Carotid artery that has an unusual shape).

    • Types:
    • Looped or Coiled
    • Kinked <90 degrees - Complains of TIA's may be from rotating head.
    • Tortuous
    • C-Shaped
    • S-Shaped
  34. 9 Risk Factors for Cardiovascular Disease:
    • 1. Atherosclerosis
    • 2. History
    • 3. Hyperlipidemia
    • 4. Smoking
    • 5. Age
    • 6. Sedentary life cycle
    • 7. Hypertension
    • 8. Diabetes
    • 9. PVD
  35. Spectral Waveform:
    1.
    2.
    3.
    4.
    5.
    • 1. Movement
    • 2. Velocity
    • 3. Turbulence
    • 4. Direction
    • 5. Amplitude
  36. Bernoulli's Principle:
    • Pressure in a stenosis decreases and velocity increases.
    • Inversely related.
    • Distal to a stenosis in turbulent flow, velocity will decrease; therefore, pressure will increase.
  37. Carotid Stenting:
    • Used as an intervention instead of CEA for patients with a high risk with coronary, pulmonary, or renal diseases.
    • Can be used when the atheroma extends beyond the accessible surgical field.
  38. CEA:
    • Involves exposing the carotid bifurcation and clamping the CCA, ICA, and ECA.
    • Clamping can compromise cerebral circulation and where appropriate, a temporary plastic shunt can be used to maintain flow between the CCA and ICA while the plaque is surgically removed.
    • Vein patches: Can be susceptible to rupture.
    • Prosthetic patches: Can be susceptible to infection.
  39. Blind Pulsed Wave:
    • 1st type.
    • Used in the detection of microembolic (MESs) by means of TCD-count and detect microemboli circulating through cerebral arteries.
  40. TCDI or TCCS

    Combines B mode imaging with frequency based color coding and doppler sonography.
    • Transcranial Doppler Image
    • Visualization of the Circle of Willis through real-time Color Doppler and PW Doppler.

    • Transcranial Color-Coded Duplex Sonography
    • Duplex sonography diagnosis of an intracranial artery occlusion based on the absence of flow signals using both color and the spectral Doppler modes.
  41. Why use TCD?
    • Intracranial Stenosis - Increase in flow velocity, spectral broadening, co-vibration phenomenon.
    • Hemodynamic Effects
    • Arterial Venous Malformations
  42. What is an AVM?
    Developmental abnormality: arteries and veins involved in supplying blood to the AVM are essentially normal and are the usual arteries supplying region of the brain where the AVM is located.
  43. You can tell it's an AVM by significant flow abnormalities:
    • Increased flow velocity.
    • Reduced Pulsatility
    • Reduced responsiveness to CO2.
  44. Why use TCD? 

    Intermittent Monitoring:
    1.
    2.
    3.
    4.
    5.
    6.
    • 1. Monitoring vasospasm.
    • 2. Subarachnoid hemorrhage.
    • 3. Severe migraines.
    • 4. ICA Occlusion.
    • 5. Anticoagulation.
    • 6. Shrink AVM's.
  45. Why use TCD?

    Continuous Monitoring:
    1.
    2.
    3.
    4.
    5.
    6.
    • 1. While doing a CEA if a shunt is not put in and if one is put in checking to see if cerebral system is okay.
    • 2. Cardiopulmonary bypass on heart-lung machine.
    • 3. Neural surgery.
    • 4. Increase ICP. (Intracranial Pressure).
    • 5. Those with severe cerebrovascular disease.
    • 6. Diagnose brain death.
  46. Why use TCD?

    Functional Testing:
    1.
    2.
    3.
    4.
    • 1. Stimulation of vasomotor.
    •     Stimulation of intracranial arterioles with CO2 or other vasoactive drugs.
    • 2. Language lateralization. 
    • 3. Pre-evaluation look at collateral flow in circle of Willis.
    • 4. Stimulation of visual cortex.
  47. Pre-TCD Exam:
    • 1. Perform Carotid Exam.
    • 2. Have patient resting to avoid PCO2 fluctuations.
  48. Transcranial Exam:

    1.
    2.
    3.
    4.
    5.
    6.
    • 1. Cranial windows.
    • 2. Insonation.
    • 3. Flow direction.
    • 4. Spatial relationships.
    • 5. Relative Flow Velocity.
    • 6. Response to oscillational compression.
  49. Acoustic Windows:

    1.
    2.
    3.
    4.
    • 1. Transtemporal
    • 2. Transorbital
    • 3. Suboccipital
    • 4. Submandibular
  50. Transtemporal Window:

    MCA
    MCA/ACA bifurcation
    ACA
    TICA
    PCA
    • MCA: toward (3-6 cm) 55cm/s
    • MCA/ACA bifurcation: bidirectional (5.5-6.5 cm) 
    • ACA: away (6-8 cm) 50cm/s
    • TICA: bidirectional 55cm/s
    • PCA: P1 toward and P2 away (6-7 cm) 40cm/s
  51. Transorbital Window:

    Ophthalmic A
    • towards
    • 4-6cm
    • 20cm/s
    • high pulsatility
    • high resistance
  52. Transorbital Window:

    Carotid Siphon
    • C2  Supraclinoid: 40-50cm/s (distal most ICA segment)
    • C3  Genu: bidirectional
    • C4  Parasellar: (proximal most ICA segment)
  53. Suboccipital Window:
    • Foramen Magnum.
    • Vertebral A: 6-9cm 
    • towards
    • 35 cm/s


    • Basilar A: 8-12cm
    • 3-4 cm long
    • 40cm/s
    • away
  54. Submandibular Window:
    Evaluation of distal extradural parts (C5 and C6 segments) of the ICA.

    • C5 
    • away
    • 30cm/s
    • 6 cm
  55. Brain death:
    1.
    2.
    3.
    • 1. Clinical criteria
    • 2. EEG
    • 3. Angiographic demonstration of absent intracranial circulation.
  56. Drop Attacks:
    • Vertebrobasilar symptom.
    • Collapse, but don't lose consciousness.
  57. Dysarthria:
    • Difficulty speaking. 
    • Tongue muscles, not working properly.
    • Vertebrobasilar symptom.
  58. Dysphagia:
    • Vertebrobasilar symptom.
    • Difficulty swallowing.
  59. Dysphasia:
    Difficulty with speech.
  60. Spontaneous rupture of aneurysms typically results in SAH and affects up to _____ patients annually.

    ____ of the people with a ruptured aneurysm die before reaching the hospital.

    ___ die in 1 to 3 months.
    40% mortality rate.
    • 30,000
    • 10-15%
    • 40%
  61. Non-traumatic saccular aneurysms occur in the anterior circulation (MCA, ACA, ACoA, and sometime the PCA) approx. ____% of the time and approx ____% of the time occur in the posterior circulation (PCA, Basilar A, Vertebral A).

    ____% of the population harbors an enraptured aneurysm.

    Most patients are _______, but may have a _______.
    • 90%
    • 10%
    • 1-5%
    • asymptomatic, severe headache
  62. Treatment for cerebral aneurysm:
    • Clipping
    • Coiling
  63. TAMV:
    time average maximum velocity
  64. Pulsatility Index:
    PI = PSV-PEDV/ Mean Velocity

    • Sensitive to diastolic runoff.
    • As vessels vasodilate-Increase in diastolic runoff, PI decreases

    PI for TCD 0.80-1.20
  65. SAH
    • Vasospasm occurs 4-14 days post hemorrhage.
    • TCD performed everyday. ---> Look for increase in vasospasm, increase in velocity.
    • <80 cm/s Normal
    • 80-120cm/s Moderate Spasm
    • 120-140 Severe Spasm
    • >140cm/s Severe Spasm causing lots of damage.

    • >20cm/s increase each day = poor prognosis, bad hemorrhage.
    • >200cm/s causing permanent damage. High morbidity rate.
  66. TCD used for brain death.
    • Sharp high resistance - Low volume, low velocity.
    • Dampened waveform.
  67. AVM's
    • Not all malformations of the brain become symptomatic.
    • Found incidentally may not demand surgical intervention.
    • However some carry a high risk of hemorrhage.
    • What is looked at is to try and identify vessels feeding the AVM.
    • Goal is to eliminate the AVM or a cerebral aneurysm.
  68. AVM's Treatment:

    Surgery.
    • Radio surgery:
    • Small AVM's inaccessible to surgery can be eradicated effectively and at low risk to radiation.
    • Stereotactic techniques used in conjunction with angiography allow doctors to identify the precise location of the AVM.
    • High energy focused radiation can be directed to the center of the AVM to decrease injury to surrounding brain tissue.
  69. Endovascular Treatment of AVM's:
    • Involves the injection of acrylic material through slender micro catheters which are navigated through the cerebral arteries to the abnormal vessels in the AVM.
    • The strategy is to eliminate particularly dangerous components of the AVM and decrease flow through it.
  70. 8 ECA Branches (PROX to DIST)
    • Superior Thyroid A
    • Ascending Pharyngeal A
    • Lingual A
    • Facial A
    • Occipital A
    • Posterior Auricular A
    • Maxillary A
    • Superficial Temporal A
  71. ANASTOMOSIS #1

    Facial A -->______<--_______<--______<--_______
    Facial A --> Angular A <--Nasal A <--Ophthalmic A <-- ICA
  72. ANASTOMOSIS #2 

    Superficial Temporal A-->____-->_____-->___
                                    -->____-->
    • Superficial Temporal A-->Frontal A--> Ophthalmic A-->ICA
    •                            -->Supraorbital A-->
  73. Pulse wave Doppler:
    ____ Sample Gate
    ____Velocities
    Color Doppler:
    ____Sample Gates
    ____Velocities
    • true
    • many
    • mean
  74. Spectral Doppler:

    Color Doppler:
    Fast Fourier Transform

    Autocorrelation
  75. Autocorrelation:
    Used to compare multiple pulses along a single scan line for frequency shift.

    Requires at lease 3 pulses per scan line, US machines usually use between 6-20.

    • Provides:
    • Direction
    • Avg. Frequency Shift
    • Power or Amplitude
    • Variance
  76. Doppler:

    Color Maps
    Velocity Map
    (top-toward, bottom-away) Vertical display.
    Variance Map
    Horizontal display.
    Detects turbulent flow easier.
  77. Color Doppler: Displays velocities throughout the scan field.

    Power Doppler: Estimates the strength of the Doppler Shift from each location.
  78. Power Doppler:

    Advantage:
    -
    -
    -
    Disadvantage:
    -
    -
    • Advantage:
    • - Sensitive to slow flow. 
    • - Never aliases.
    • - Angle does not effect it.
    • Disadvantage:
    • - Cannot determine direction.
    • - Frame rates drop.
  79. Packet Size:
    How many sample areas per a line.
  80. Line Density:
    How many lines in the color box area.
  81. Who is responsible for ensuring that US machines maintain good safety records?
    American Institute of Ultrasound (AIUM)
  82. Gray-scale US instruments use only 2 pieces of information:

    The _____ from the _____ to the _____ (Determined by the time of flight US pulse).

    _____ of the echo.
    distance, echo, transducer

    strength
  83. Color Dopper US instruments use:

    Doppler shift information in addition to ___________ and ___________.
    time of flight and amplitude
  84. Time-Domain Color Flow Imaging US Instrument:

    Identifies _________ and notes how far these cluster _____ on ___________.
    • clusters of echoes
    • move
    • successive US pulses
  85. Power Doppler:
    Estimates the strength of Doppler shift from each location of the image field and displays any Doppler Shifts that exceed.
  86. TCPO2:
    Transcutaneous Oximetry

    • Non-invasive monitoring of the oxygen tension in the skin.
    • Direct indication of the microvascular function.
  87. TCPO2:
    • Diagnosis of ischemia.
    • Healing probability.
    • Suggesting amputation level.
    • Plastic surgery.
    • Hyperbaric medicine.
    • Orthopedic surgery.
    • Successful revascularization.
    • PVD assessment.
  88. TCPO2

    Measuring:
    • Polarographic oxygen electrode.
    • Electrode heats skin to 44-45 degrees Celsius.
    • Oxygen is consumed by the electrode.
    • Electrode is calibrated with gas or with a solution of known PO2.
  89. TCPO2:
    • Room temperature 70-73 degrees Fahrenheit.
    • Electrode placement.
    • Instruct patient:
    • No caffeine 30 minutes prior to test.
    • No smoking 30 minutes prior to test.
    • No talking during test.
    • No excessive movement during test.
  90. TCPO2:

    Electrode Placement.
    • Do not place on:
    • ulcers
    • cellulitis
    • skin close to bone
    • large superficial vessels
    • pulse sites
  91. TCPO2 Protocol:
    • Calibrate electrode.
    • Select measuring site.
    • Clean site.
    • Apply fixation right.
    • Fill fixation ring with 3-5 drops of contact liquid.
    • Fasten electrode to fixation ring.
    • Wait for stable reading.
    • Stable reading can take 15-20 minutes.
  92. TCPO2 

    Healing probability.
    • Healing will occur 70-80 mmHg.
    • Borderline healing will occur 30-40 mmHg.
    • Non-healing will occur 10-15 mmHg.
  93. Reynold's Number:
    • Used to determine if flow will be laminar or turbulent.
    • It is the ratio of inertial forces to viscous forces.

    • If Reynold's Number is <2000 = Laminar Flow.
    • If Reynold's Number is >3000 = Turbulent Flow.
  94. Raynaud's Disease VS. Raynaud's Phenomenon
    • Raynaud's Disease:
    • Primary Raynaud's Phenomenon
    • Color change. (white, blue, red)
    • Anecrotic Notch.

    • Raynaud's Phenomenon:
    • Secondary Raynaud's Phenomenon
    • Underlying cause.
    • Dampened waveform.
  95. Raynaud's Treatment:
    • Calcium Channel Blockers
    • Biofeedback
    • Vasodilators
  96. Temporal Arteritis OR Giant Cell Arteritis:
    • Superficial Temporal A wall is inflamed.
    • Usually larger in diameter with homogeneous clearly seen on B-mode.
    • Anechoic "halo" from edema of the intima may or may not be seen.
    • Intimal thickening --> May result in hemodynamically significant stenosis where PSV's are twice as high.
    • Over growth of smooth muscle.
    • Occurs more often in +50 year olds.
  97. Blue Toe Syndrome:
    • Emboli
    • Heart
    • Ulcerated Plaque
  98. Takayasu's Disease:
    • Unknown etiology, but believed to be an autoimmune mechanism.
    • Media and adventitia become inflamed.
    • Walls become thick and artery shortens.
    • Fibroelastic tissue multiplies in the media and adventitia.
    • Pebble like appearance.
    • Small aneurysms can develop.
    • Thrombus can form.

    Young Asian women.
  99. Thromboangiitis Obliterans (TAO):
    (Buerger's Disease)
    • Involves small-medium sized arteries in arms and legs.
    • Causes focal inflammations, with no necrosis, primarily in the most outer layer of the artery wall.
    • The intima thickens but no lipid formation happens.
    • Could cause arterial thrombosis or thrombophlebitis.

    Young male smokers.
  100. Periarteritis nodosa:
    • Focal inflammatory lesions are found in small-medium sized arteries.
    • Inflammation involves all layers of the artery.
    • May have aneurysm form then rupture.
    • More common in men. 
    • 50-60 years old.
  101. MR Angiography (MRA):
    Uses radio frequency energy and a strong magnetic field to produce images in multi planes.

    MRI (Magnetic Resonance Imaging) instruments quantitate blood flow and construct images that look like angiograms from soft tissue without using contrast agents. 

    Uses non-ionizing radiation.
  102. MRA Limitations:
    • Metallic clips, pacemakers, monitoring equipment.
    • Inability to accurately assess degree of stenosis.
    • Can overestimate stenosis due to slow flow or turbulence. Resulting loss of magnetic signal.
  103. MRA is used to look at:
    • AAA
    • Dissections
    • PVD

    Also used as a GOLD STANDARD.
  104. Computerized Tomography (CT):
    Uses ionizing radiation.

    IV Contrast.

    • Used to determine size of aorta and of aneurysm.
    • Aids in identification of renal arteries to aorta.
  105. CT Limitations:
    • Patient movement/ presence of metal surgical clips will lessen image quality.
    • Requires more time and is more expensive than US.
    • One plane is used.
    • Limited on small arteries trying to locate PVD.
  106. Positron Emission Tomography (PET):
    Doesn't show the body's anatomy but rather shows the chemical function or metabolism of an organ tissue.

    Patient receives IV of radioactive fluorine and then they need to lie still for 45 minutes while the isotope circulates throughout the body.
  107. Perma-cath:
    Radiologist will access the IJV and advance a guide wire in the SVC where the catheter enters the skin and where the needle puncture is made.

    Cuff that is attached that helps secure, scar tissue builds up around the cuff.

    • Procedure takes 45 minutes.
    • Chest X Ray taken afterwards.
  108. An electrical charge is expressed in _______.
    coulomb
  109. Flow of electrons through a conductor produces an ________.

    measured in ______
    analogous to ______
    • electrical current
    • amperes
    • blood flow
  110. The driving force, which propels flow of current and determines its magnitude, is the ______.

    measured in ______
    analogous to ______
    • voltage
    • volts
    • blood pressure
  111. The resistance of any conductor to the flow of current is called the ________.

    measured in _____
    analogous to ______
    • electrical resistance
    • ohms
    • vascular resistance
  112. Ohm's Law
    Voltage = _____x_____

    Hemodynamic analogy to Ohm's Law is:
    Pressure = ______x______
    current x resistance

    flow x resistance
  113. Electrical resistance is = to the length of the conductor and inversely proportional to the cross sectional area of the conductor.
  114. Energy:

    Total amount of electrical power expended by the passage of the electrical current.

    Units of _____
    _______ is measured by multiplying the _________ by the ________ it is used.
    • Joules
    • Energy, average power, total time
  115. Power:

    Units of _____
    measure of how fast electrical work is being done.
    Power = V or E x Current (I)
  116. Quality Assurance:
    -
    -
    -
    -
    • Validate a non-invasive vascular test
    • DSA - Digital Subtraction Angiography
    • MRA - Magnetic Resonance Angiography
    • Carotid Angiography
  117. True Positive:
    • Both tests say that there is disease.
    • (Carotid disease has to be >50% to be considered positive).
  118. True Negative:
    Both tests say that there isn't disease.
  119. False Positive:
    You perform the study and say it is positive for disease, but it is actually negative.
  120. False Negative:
    You perform the study and say it is negative for disease, but it is actually positive.
  121. Sensitivity:
    • 100%  they have disease.
    • The ability to detect disease with a non-invasive study, confirmed by the "Gold Standard" finding to be abnormal.

    TP/(TP+FN)x100
  122. Specificity:
    • 100% they have NO disease.
    • The ability to detect NO disease by a non-invasive study, confirmed by the "Gold Standard" finding to be normal.

    TN/(TN+FP)x100
  123. Positive Predictive Value (PPV):
    The % of non-invasive tests that were accurate in predicting an abnormal study confirmed by "Gold Standard".


    The likelihood that the US and "Gold Standard" are both positive.

    TP/(TP+FP)x100
  124. Negative Predictive Value (NPV):
    The % of non-invasive tests that were accurate in predicting a normal study confirmed by "Gold Standard". 

    The likelihood that the US and "Gold Standard" are negative.

    TN/(TN+FN)x100
  125. Overall Accuracy:
    Disease and NO disease overall. (How good was the study).

    [(TP+TN)/(TP+TN+FP+FN)]x100
  126. Prevalance:
    Dealing with the incidence of disease.

    [(TP+FN)/(TP+TN+FP+FN)]x100

Card Set Information

Author:
jrw10
ID:
317287
Filename:
CORE II VASCULAR
Updated:
2016-03-13 18:46:01
Tags:
vascular
Folders:
vascular
Description:
Vascular
Show Answers:

Home > Flashcards > Print Preview