Term
What is the Doppler equation for frequency shift? |
|
Definition
|
|
Term
What is the Doppler equation for solving estimated velocity? |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
speed of sound through a medium |
|
|
Term
What is the main reason to perform a carotid scan? |
|
Definition
To look for hemodynamically significant atherosclerotic lesions that may lead to stroke |
|
|
Term
What are two causes of stroke? |
|
Definition
Ischemia caused by embolic activity or flow restriction through hemodynamically significant lesions and hemorrhage caused by rupturing of a vessle in the cerebrovascular system. |
|
|
Term
A stinosis of 50% in diameter is how much in area? |
|
Definition
|
|
Term
A stinosis of 80% in diameter is how much in area? |
|
Definition
|
|
Term
What type of stroke is most common? |
|
Definition
Ischemic caused by embolic activity |
|
|
Term
What type of stroke is least common? |
|
Definition
Hemorrhagic caused by rupture of vessel |
|
|
Term
What are 6 symptoms of carotid territory? |
|
Definition
1. amaurosis fugax: temporary blindness in one eye (embolic activity same side ICA Opthalmic Artery) 2. hemiparesis: weakness (contra-lateral) 3. hemiplegia: paralysis 4. hemiparesthesia: numbness or tingling 5. dysphasia:slurred speech; or aphasia: absence of speech (left side of brain if right handed; not clear for left handed) 6. homonymous hemianopia: loss of half the vision in both eyes (carotid) |
|
|
Term
What are 5 symptoms of vertebrobasilar territory? |
|
Definition
1. Binocular vision disturbance 2. Syncope or near-syncope 3. Vertigo/dizziness 4. Nausea 5. Ataxia: loss of coordination; gait awkwardness |
|
|
Term
What is the grading criteria for a 50% stinosis of the ICA? |
|
Definition
|
|
Term
What is the grading criteria for a 70% stinosis of the ICA? |
|
Definition
|
|
Term
What is the grading criteria for a 80% stinosis of the ICA? |
|
Definition
|
|
Term
What are the main reasons to perform a LE venous scan? |
|
Definition
|
|
Term
What percentage of PE cases are caused by thrombi traveling from the lower extremities as a result of DVT? |
|
Definition
|
|
Term
What is the single best indicator of DVT? What are other symptoms? |
|
Definition
Acute unilateral edema; swelling and pain (dull aching) |
|
|
Term
What are the 13 (Baker's Dozen) risk factor for DVT? |
|
Definition
1. Age 2. Obesity 3. Pregnancy 4. Oral contraceptives 5. Trauma 6. Varicose veins 7. Congestive Heart Failure 8. Surgery 9. Infection 10. Previous DVT 11. Prolonged bed rest or sitting 12. Cancer 13. Dehydration |
|
|
Term
What are the 5 Image Characteristics associate with acute (fresh) thrombus? |
|
Definition
1.Homogeneous appearance 2.Lightly speckled soft/dark echoes 3.Partly compressible--spongy 4.Incomplete adherence to wall--possible presence of "tail" 5.Distended vein |
|
|
Term
What are the 8 Image Characteristics associated with chronic thrombus? |
|
Definition
1.Heterogeneous appearance 2.Bright echos 3.Incomprssible--rigid 4.Firmly attached to wall 5.Possibly partly recanalized; may see anything from rather tiny residual lumen to thin, bright flap in the middle of the lumen 6.Brightly echodense, irregular-appearing walls 7.No evidence of any venous lumen adjacent to the corresponding artery--thrombus may have echo character similar to surrounding tissue 8.Presence of large collaterals |
|
|
Term
What are some reasons to perform a LE arterial scan? |
|
Definition
1. Chronic atherosclerois 2. Acute occlusion 3. Aneurysm 4. Pseudoaneurysm 5. Arteriovenous fistula 6. Follow-up assessment of bypass grafts |
|
|
Term
What are some common sites for LE ASO? |
|
Definition
1. Aortoiliac bifurcation 2. CF bifurcation 3. Adductor canal 4. Origins of tibials |
|
|
Term
What are the stages of symptoms of LE ASO? |
|
Definition
1. Asymptomatic 2. Claudication: pain on exercise, relieved by rest; level of pain suggests level of obstruction (obstruction is proximal to pain) 3. Rest pain: usually toes and feet (far end of periphery) 4. Ischemic ulcer: usually due to injury (it takes more perfusion to heal tissue than just to sustain it) 5. Gangrene: tissue death due to ischemia |
|
|
Term
What is the grading criteria for a significant stinosis (>50%-60%)of the LE Artery? |
|
Definition
200 cm/sec and/or 2:1 ratio |
|
|
Term
What is the grading criteria for a severe stinosis (>75%-80%)of the LE Artery? |
|
Definition
400 cm/sec and/or 4:1 ratio |
|
|
Term
What are the two most common reasons to perform abdominal Dopplers? |
|
Definition
1. Renal artery stinosis/Renal vascular HTN 2. Messenteric artery stinosis/Bowel ischemia |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
Superior Mesenteric Artery Preprandial |
|
|
Term
|
Definition
Superior Mesenteric Artery Postprandial |
|
|