Transcranial Doppler and Imaging
Card Set Information
Transcranial Doppler and Imaging
What does MESs stand for?
What are three ways to tell if AVM?
1.) increased flow velocity
2.) reduced pulsatility
3.) reduced responsiveness to CO2
What does AVMs stand for?
Arterial venous malformations
What percent of large to medium sized AVMs can we find using TCD?
What are 3 main types of monitoring use TCD?
What is the most common?
1.) intermittent monitoring
2.) continuous monitoring
3.) functional testing
Intermittent is the most common
What are 6 reasons why we might use intermittent monitoring using TCD?
1.) monitoring vasospasm
2.) subaraqchnoid hemorrhage
3.) severe migraines
4.) ICA occlusion
5.) anticoagulation given
6.) shrink AVM's
What are 6 reasons why we might use continuous monitoring using TCD?
1.) While doing a CEA
2.) Cardiopulmonary bypass on heart
3.) Neural surgery
4.) Increase ICP or intracranial pressure
5.) Diagnose brain death
6.) those with severe cerebrovascular disease
What are 4 reasons why we might use functional testing using TCD?
1.) simulation of vasomotor
2.) language lateralization
3.) pre-evaluation look at the collateral flow in circle of willis
4.) stimulation of visual cortex
What are 2 main things we need to do before a TCD?
1.) Do a Carotid Duplex to evaluate extracranial artery status.
2.) Have patient resting to avoid PCO2 fluctuations.
What are the 6 things we look at when doing an transcranial exam? (not specific things)
1.) cranial windows
2.) Insonation depth (cm)
3.) Flow direction
4.) Spatial relationships
5.) Relative flow velocity
6.) Response to oscillational compression
What is oscillational compression?
compress of CCA
Which acoustic window is the thinnest?
What degree of insonation do we use for TCD?
Can use other places?
Can be 0-30 degrees
When using relative flow velocities what are we using?
Time Average Maximum Velocity
What does Dysarthia mean?
What does Dysphagia?
What does Dysphasia mean?
difficulty with speech
What does intracranial mean?
within the cranium
What does contralateral mean?
relating to the opposite side
What does Ipsilateral mean?
What does ICP mean?
What does CEA mean?
What does hypoplastic mean?
small or not there in vessel system
What does hypoperfusion mean?
low blood pressure
What does spontaneous rupture of aneurysms typically result in?
How many people annually?
How many die on the way to hospital?
How many die in 1 to 3 months?
What is the mortality rate?
SAH - Subarachnoid hemorrhage
10-15% with ruptured die on the way to hosp.
40% die in 1 to 3 months
40% morality rate
How many NOn-traumatic saccular aneurysms occur in the anterior circulation?
How many in the posterior circulation?
90% anterior circulation
10% in the posterior circulation
What are the symptoms of non ruptured aneurysms? (2)
Most people are asymptomatic
Some have a severe headache
What are two treatment options for cerebral aneurysms?
What is the main treatment?
How is it done?
Artery is exposed and a metal clip blocks flow to the aneurysm
What is another name for coiling?
Guglielmi Detachable Coiling (GDC)
How does GDC work?
Fill the aneurysm with coils and thrombus
What is the frequent site for aneurysm formation and is the most common site of aneurysms associated with subarachnoid hemorrhage?
Anterior Communicating Artery
What is the second most common site for aneurysm formation?
Posterior Cerebral Artery
What is the third most common site for congenital aneurysms aneurysm formation?
Where does approximately one-fourth of all intracranial aneurysms come from?