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120 Cards in this Set
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explain the qualitative assesment of peripheral arterial-non-invasive tests
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-triphasic is normal, and it changes to monophasic as disease progresses
-monophasic waveforms can be seen both proximal and distal to an obstruction -observe deterioration of a signal from one sement to the next |
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explain how segmental pressure testing is interpretated?
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ABI:
normal->.95 single segment disease=.5-.9 multi-segment disease=<0.5 associated w/ rest pain=<0.3 |
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explain the technique for exercise testing
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-treadmill is at 1.5-2mph w. 10 degree elevation for max of 5 minutes or until symptoms prevent the patient from continuing.
-immediately following exercise, obtain pressures from both ankels, and the arm, so ABI's can be calculated -arm w/ the highest brachial pressure is used -post exercise ankel pressures should be monitored for upto 10 minutes until to pre-exercise pressures are readched |
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explain the patient postion, and technique for reactive hyperemia?
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Patient postion-supine w/ thigh cuffs applied
Technique-thigh cuffs are inflatted to occlude flow and are maintained for 3-5 mintues -ankle and brachial pressures are obtained after cuff deflation |
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HOw is reactive hyperemia interpreted?
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-pressure drops in diseased libs are similar to those after treadmill testing
-single level disese=<50% pressure drop -multi-level disease=>50% pressure drop |
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explain the procedure for SPG
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-aka strain guage plesmography
-patient in warm room -silastic band -measures a change in circumference by sending an electrical pulse through a limb |
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plesmography
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to recod an increase;records the diffeence in volume of a cuff; can be measured by:
-volume -circumference -electrcal imepednce -light relfectance |
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name and explaint the categories of stenosis, their percentages, waveforms, spectral broadening, and PSV
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NORMAL:
-0% stenosis -no plaque on walls -triphasic waveform MILD: -1-19% steosis -triphasic waveform -some spectral broadening -PSV is less than double that of closest prox normal segment MODERATE: -20-49% stenosis -PSV less than double that of closest prox normal segment -marked spectral broadening -may be biphasic due to attenuated reverse component SEVERE: -50-99% stenosis -increased systolic velocity by>100% -PSV douple the proximal adjacent segment(>200cm/sec) -marked spectral broadening -Reverse flow component is absent NEAR OCCLUSION: ->80% -flow dininishes and waveform becomes damped -reverse flow component is absent TOTAL OCCLUSION: -no flow -systolic thumping prox to occusion -collateral re-entry distal to occlusion identified by a low velocity, monophasic flow pattern w/ spectral broadening |
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what are the limitations of plethysmography?
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-significant prozimal arterial disease may reduce digital profusion causing a near flat line waveform which eliminates the ability to evaluate digits from small vessel arteries
-in cold climates, patients may present w/ normal vasoconstriction of digital arteries(extremities should be warm before plethysmographic evaluation) |
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what are the capabilities of exercise testing?
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-differentiate btw true claudiation and pseudoclaudication
-help determine presence or absence of collaterals |
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what arteries supply collateral circulation?
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-lumbar
-MCA -SMA |
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what is the most valuble feature of PVR?
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is not affected by calcified vessels; this is a better test than Segmental pressure testing when there is significant arterial calcification and arteries are difficult to occlude w/ segmental pressure testing
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what is the major limitation of peripheral arterial non-invasive testing
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-inability to locaize specific segment of diesease
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PVR
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pulse volume recodint(aka segmental air plesmography)-measures a cnange in dimention of a limb or body part in response to a change in blood content
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how should exercise testing be interpretated?
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NORMAL: pressures stay the same or show a slight increase
ABNORMAL-pressures decrease during and after exercise a)single level disease-pressures return to normal within 2-6 minutes b)multi level disease-pressures remain decreased for 12 or more minutes c)after exercise, ankle pressures below 60mmHg confirm a vascular etiology for claudication |
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MVO
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maximum venous outflow-the rate of outflow following release of vnous tourniquet
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what is the exception for ABI normals?
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-if the brachial systolic pressure is <100mmHg, or >200mmHg, the ankle pressure may be 20% lower than brachial pressure
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what are some ways to quantitiate a doppler waveform?
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-PI-independant of angle; increases from prox to distal(peak to peak/mean height)
PI of CFA of >6 in normal without SFA disease, a PI <5 indicates aorto-illiac disease -acceleration time =>144cn=abnormal----from onset of systole to peak velocity; increase indicates proximal disease -acceleration idex-change in PSV-onset SV/accel time AI<3.78kHz=abnormal |
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explain finger indices, and pressures
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Normal finger/arm index is >0.95
-finger pressure should be>arm pressure -wrist/finger gradient should not exceed 30mmHg |
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Arterio-liliac inflow system; what is it, know where it is on a diagram
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-refers to major vessels supplying blood to the arteries of the lower extremity
-extends from aorta @ renal artery level to inguinal ligaments of each leg and includes the common and external iliac arteries -if there is obstruction at this site, there is limited blood supply to either or both legs. -this is the second most common site for atherosclerotic disease of the lower extremity |
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what does an abnormal gradiant btw below the knee cuff and the ankle cuff indicate?
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-ibioperneal(runoff) occlusive disease
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what is normal when comparing bypass graft ?
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-it is a normal finding to observe retrograde flow into the bypassed segment of the native artery due to decreased pressure
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what is the PVR technique?
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-inflate thigh cuff to 65mmHg with a volume of 400+-75CC
-inflate calf and ankel cuff to 65mmHg w. a volume of 75 +-10CC of air |
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what are the capabiliteis of plethsymography?
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-definig vascular etiology for digital symotms including blue toe syndrome
-differentiate small vessel atherosclerotic disease from vasospastic disorder |
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what are the limitations of PVR?
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-edema, tremor, A-fib, distal disease, warm room have to haev tension on cuff
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photoplesmography
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(PPG):
-2 crystals -one emits infared light, and the other recieves reflected light -produces an analog waveform -not a true plethysmograph -excellent for digital profusion |
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what is the normal, abnormal, claudication, and rest pain ABI numbers for TBI's
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Normal-0.8-0.9
abnormal-<0.66 claudication-0.35-0.15 rest pain-0.11-0.1 |
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PORH
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post occlusive reactive hyperemia:
-sometimes substitueded for treadmill exercise -low thigh systolic pressure is kept on for 3 minutes -following release, the anke presure is recorded -with occlusive disease, there is a significant dicrease in ankle pressure when thigh cuff is released. |
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when are tourniquets used?
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-in PPG venous reflux testing, they may be used to occlude the greater saphenous vein and lesser saphenous to help diffentiate superficial from deep vein incompitancy
-if abnormal venous reflux becomes normal after retesting w/ tourquinets, the incompetance is likely in the supericial venous system and perforators -venous outflow may be reduced w/ blood pressure cuff tourniquets placed on thigh |
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Transcutaneous oximetry
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-aka TCOP2:
-measures oxygen ontent in the tissues which indicates perfusion -depends on balence btw O2 supply and O2 consumption of patient -measurement of PO2 at the surface of the skin are usually within 1-2% of the true value -useful in determinig wound healing potential and amputation level. |
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w/ishemia, what may happen to arterioles?
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-they may remain dialated in order to allow more blood flow to tissues, resulting in a monophsic waveform
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strain guage plesmography
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-measures circuference
-alternative to CW and PVR -based on electrical impedence -qualitiative, not quantitative |
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what are the normal varients of the poterior tib, and peroneal arteries?
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-absent posterior tibial artery(5%)
-peroneal artery arising formt he anterior tibial artery |
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explain venous outflow and tourniquets
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-venous outflow may be reduced w/ blood pressure cuff tourniquets placed on the thigh.
-w/ a supine patient, 50mmHg cuff will restrict venous outflow until the intraluminal pressure exceeds cuff pressure -at this point, flow resumes -tourniquet restriction, and rlease is the basis of measureing venous capacitance and outlflow. |
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pseumo-plethysmography/air plethysmography
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known as PVR(pulse volume recording, pulse cuff recording, or volume pulse recording
-records a volume change in a limb related to pulsisitle arterial flows -usual type of recording device is a PPG -PPG uses transmitted and reflected infared light to record cutaneuous blood flow |
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with segmental limb testing, what are the pressures compared to?
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-contralateral limb presures
-adjacent segments -brachial pressure |
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velocimetry
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method of assessing location and semiquantitative severity of disese
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tibial peroneal run-off system
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-starts at the termination of the popiteal artery and extends to the level of the ankle
-receives runoff blood from both systems above -even w/ total occlusion of SFA, flow can be identified in this system because of collateral flow by the profunda artery -occlusion to CFA-no flow in tibioperoneal run off system becuse both SFA and profunda receive no flow |
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compare skin changes in chronic arterial insufficiency to chronic venous insufficiency
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Arterial-thin shiny skin w/ loss of hair; thickened nails
Venous-brown pigmentation around the ankles; dermatitis may be evident |
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acute venous thrombosis
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-usually begins at soleal sinuses and propegates up the leg; or it forms at the site of venous intimal injury
-higher risk as the disease moves proximally -thrombus from trauma may occur at any level - |
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warm testing
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done when patient arrives with digits already in vasospasm
-differentiates btw primary and secondary reynauds |
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Explain the patient position and techique for air outflow plethsymography
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PATIENT POSITIONING:
-supine w/ head flat and calf above heart to facilitate drainage -knee bent -leg externally rotated TECHNIQUE: -monitoring transducers are placed on the calf to detect volume changes as the cuff is inflated and deflated -occluding cuff placed above the knee and inflated above venous pressures, but below arterial(45mmHg) for 2 minutes -cuff is rapidly deflated and three second ouflow is measured |
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predisposing risk factors for peripheral venous disease
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-age
-cancer-malignancy -pregnancy -hormonal changes -recent surgery -immobility -congenital thrombophilia -previous DVT |
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how do you differntiate vasospasm vs. small vessell disease with digital evaluation?
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-rule out proximal disease
-recond pre-submersion PVR's or PPG's, warm the hand and retest -if sensitive to cold, test for vasospasm |
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what test is used for arterial TOS?
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-plesmography
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How is sympathetic nerve activity interpreted?
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NORMAL PATIENT(intact sympathetic nervous system):
-inspiration-rapid rise in digital volume -respiration suspended-plethsymographic tracing becomes level -expiration-rapid decrease in volume PATIENT FOLLOWING SYMATHECTOMY(nerve removal): -inspiration-initail rise in digital volume -expiration-no change in pulse volume and total digit volume |
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Explain the capabilites and limitations of photo outflow plesthsmography
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CAPABILITIES:
-helps evaluate venous insufficiency LIMITATIONS: -inability to determine the site of involvement -cannot differentiate btw superficial and deep -collaterals affect results -venous stasis ulcere in malleolar area may limit th exam |
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what are the TOS positions?
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1. abducted 90 degrees to torso
2. elevated 180 degrees above head 3. arm abducted 90 degrees above head with elvow bent 90 degrees(pledge position) -elevate with the head turned toward, ten away from hand. 4. elbows at side and to the back, hands up, shoulders pressed downward and back(stick up position) 5. most MB postition=symptomatic position |
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What are the causes of venous insufficiency?
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COMMON:
-right sided heart failure -DVT -extrinsitc compression OTHER: -lyphatic system problems -reduced mobility/paralysis |
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functional reserve tesing
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can check reactivity of the cerebral vessels with a CO2 challenge test
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explain the walls of the arteries of a person who has bergers diasese, how is it diagnosed?
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-walls are smooth until you mive distally
-diagnosed diffinitively with angiogram |
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phlegmasia curula dolens
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bluish discoloration
-results from severely reduced venous outflow from iliofemoral thrombosis, which decreases arterial flow, a limb-threteing condition |
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what are the techniques for sympathic nerve activities?
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-attach PPG sensor(PPG or SPG) to digit
-set recoding device to DC mode-timing slow blood return -have patient inhale deeply, then suspend respiration -have patient exhale rapidly |
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adson's position
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-patient hyperabducs the arm with external rotation
-followed by rotation of the head first toward and then away from the arm -this combination of postition and head motion seves to stetch the subclavian artery while the scalene muscle changes its tone. -lets you know if it's arterial or not. |
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what are the limitations of digital assessment?
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-vasocaonstriction
-cuffs applied too tightly -PPG's that are applied incorrectly -strain guage plesthsmography -patient factors |
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explain hypocapnia vs. hypercapnia?
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HYPERCAPNIA:
-excess CO2 -hypoventelation -MCA mean velocity increases -vasodialation -resistance is lowered -PI decreases HYPOCAPNIA: -hyperventalation -deficiency in C02 -MCA mean velocity decreases -vasoconstriction -PI increases -flow resistance increases |
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calf muscle veins
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-venous sinusoids collect blood from soleal and gastrocnemius muscles
-empty when calf muscle pump is activated -soleal veins-drain into peroneal or posterior tibial veins. -gastrocnemius veins drain into popiteal vein. |
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explain how different time intervals of lack of blood flow to the brain will effect it?
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-breif-unconciousness
-1-2 minutes-effects neural function ->4minutes=permanent injury |
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what are the contraindications for radial artery harvest?
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-ishcemic digits
-digit vasospastic disorder -athero occlusive disease in arms -sclerotic or small radial artery |
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how is treatment for stasis ulceration done?
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-keep area clean and medicated
-unna boot, which provides venous compression -skin grafts |
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what does functional reserve testing measure, and identify?
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measures-response of the cerebral circulation supplied by the MCA to the inhalation of 6% CO2 for 3 minutes
-identifies-patients who have or are at risk for low flow ischemia and infarction |
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what are the signs and symptms of acute and chronic DVT
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ACUTE:
-redness -edema -warm to touch -pain CHONIC: -discoloration -hyperpigmentation: brown discoloration in lower leg to ankel(gaiter zone) |
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what are the stages of arterities
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-aneurysm
-narrowing -occlusion |
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Explain the interpretation of digital assessment?
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NORMAL:
-normal systolic pressures -80% of normal ipsilateralo brachial pressures -finger-brachial index=0.8-on ipsilateral side -waveforms should be sharp upstroke and dicrotic notch OBSTRUCTIVE DISEASE: -funger pressure measurements<70mmHg -brachial/finger differences>35mmHg FINGERTIP ISHCEMIA: -wrist to digit difference=30mmHg -finger to finger difference=15mmHG |
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phlegmasia alba dolens
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-whiteness of lower extremity caused by arterial spasms due to extensive, acute iliofemoral thrombosis, a limb-thrteming condition
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explain the etiology of venous ulceration?
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-chronic increase in intraluminal pressure
-increase in vein wall permeability -plasma and fibrogen leak into surrounding tissue -fibrinogen converts to fibrin -barrier formation between capillaries and tissues -decrease of oxygen and nutrient delivery -subcutaneous bacterial infection |
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explain primary and secondary varicose veins?
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PRIMARY:
-inherent weakness of the vein walls not related to thrombosis -congenitally incomplete valves SECONDARY: -due to pathology of the deep venous system |
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what are the capabilites and limitations of air outflow plesthympgraphy?
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CAPABILITIES: can detect obstructive thrombus in the liliac, femoral, and popiteal veins
LIMITATIONS: -unable to detect calf vein thrombus -cannot detect small thrombus -false positives may occur with: CHF, tricuspid insufficiency, severe pulmonary problems, severe arterial insufficiency, extrinsic obstructions such as a tumor. |
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hypercoagulability
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thrombophillia-protein c and protein s deficiency
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what are the phases of the cardiac cycle where there is increased venous flow?
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2 phases:
1st phase-durind systole-decreased atrial pressure causes flow in extra cardiac veins to increase 2nd-after AV valves open, and blood rushes into the ventricles from the atria |
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when is it normal for ankle pressures to return to preexercise levels with hyperemia?
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30-60sec post exercise
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Virchow's triad:
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Virchow's triad:
-endothelial damage -vneous stasis -ypercoagulability |
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where is there not valves in the lower extremity veins?
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-the IVC, common, and internal illiacs
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skin thermometry
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-not done very often because it's hard to control
-when 2 adjacent areas exhibit noticable temperature differentces under identical conditions, this is suspicous for vascular disease or spasm |
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explain the technique for digital assessmet?
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-rule ou proximal larger vessel arterial disease
-cuff selection(1.5xdiameter of digit) -apply @ base of finger -photocell(strain guage) application-at distal digit -PPG waveforms for each digit -pressures taken as an endpoint |
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Explain how the superficial veins of the upper extremity run?
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-superficial digital veins drain blood from tissues into deep veins
-superficial digital veins of the hand unite near the wrist to form cephalic and basilar -cephalic courses on the radial side, and cephalic unites w/ axillary and empties into the subclavian -basilic courses on the ulnar side, and unites with the brachial vein to become the axillary vein. |
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what is the patient postion, and technique for photo outflow plethsmography?
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POSITION: seated w/ legs dangling
TECHNIQUE: -PPG transducers appled to skin near medial malleolus -dorsiflexion and plantar-flexion of the feet performed 5 times to provide calf muscle pumping -leg is then completely relaxed |
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explain the technique for cold testing?
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-record pre-submersion PVR's or PPG's
-place symptomatic hand in a plastic bag without removing the PPG, or PVR cuffs -submerge hand in basin of ice water for 1-2 minutes or as patient tolerates -obtain post sumbersion tracings -obtain tracings at 2-3 minute intervals -if tracings return to baseline within 5 minutes, discontinue testing -if tracings remain low, continue recording at 2 minute intervals |
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explain the skin thermometry interpretation
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Normal patient:
-digital temperature returns to normal within 15 minutes -recovery half time<8 minutes ABNORMAL PATIENT: -patients who require >20 minutes to return to normal temperature -suspect raynaud's syndrome |
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explain the method, interpretation, and limitations of venography/
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METHOD:
=contrast agent inject into foot to demonstrate venous system -radiographs taken of entire leg to demonstrate venous system and any disease that may be present LIMITATIONS: -painful for patient -chemical phlebitis may occur due to contrast agent -differntiation btw acute and chromic is difficult |
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how is air outflow plesthymography interpreted>?
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CAPACITANCE:
-volume of congested blood in teh calf after occlusion -measured from baseline, to max volume before deflation OUTFLOW: -volume of blood that flows out of the leg in the first 3 seconds after occlusion GRAFH INTERPRETATION: -capacitance and ouflow plotted on graph -if results fall below discriminent line, test is considered normal -if abnormal, repeat test 3-5 times to rule out false positive |
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what are the capabilities of CW doppler w/ peripheral venous testing?
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-can detect obstructive thrombus in the iliac, femoral, and popiteal veins.
-can detect valvular insufficiency in both deep and superficial systems |
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what are the types of chronic leg ulcers?
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-ishcemic-painful because of complete occlusion; end stage arterial disease
-neurotrophi-common to diabetics -stasis-due to venous hypertension |
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anticoagulation for DVT
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-heparin for 5-10 days
-sodium wafarin(coumadin) usually 3-6 months |
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what does arterial CO2 partial pressures effect?
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-the cerebral blood flow and intracranial arterial velocities
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explain how photo outflow plesthmography is interpreted?
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-based on the amount of time required for a stable baseline to return following the exercise
-normal recovery times =25 seconds or greater. -recoverty time <20 seconds are consistance with venous incompetnece |
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Explain arterial carbon dioxide partial pressures
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-decreased CO2=decreased cerebral blood flow, and decreased intracranial arterial velocities
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external to internal carotid collaterals
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-second most NB anastamoses
-aka preswillisian anastamosis -the best known one is btw the ECA and ICA through the orbital and opthalmic arteries |
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what are some diagnostic tests for PE and DVT?
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-lung perfusion-VQ scan(nuc med)
-spiral CT angio -lung/leg MRI -pulmonary angio(gold standard for PE) -isotope venography -contrast venography(gold standard for DVT) |
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isotope venography
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-involves the injection of I-125 labled fibrinogen
-absorbed into thrombus -a scanner then records the amount of labled fibrinogen ar various levels -highly sensitive to actively forming thrombus |
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contrast venography(phlebography)
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-gold standard study
-catheter inserted into a peripheral vein -contrast injected -radiologies observes movement of solution though veins w/ a floroscope -x-rays taken simultaneously -any filling defect indicates displacement of contrast material vy thrombus |
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what are the controlling risk factors for theraputic interventions?
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-controlling risk factors:
-promoting venous drainage -preventing endothelial damage -controlling hypercoagulability |
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Name and explain the theraputic surgical interventions?
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1)Venal caval interuptio:
-greenfiled or bird's nest filter -may be placed in the IVC, FV, or JV -Prevents emboli from moving to the lungs 2)Iliofemoral venous thrombectomy 3)ligation of superficial veins 3)varicose vein stripping or sclerotherapy |
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venous outflow plethsmography
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-combines 2 tests into 1 procedure; maximum venous outflow(MVO), and venous volume(capacitance)measurements
-allows determination of whether deep vein thrombosis is present at or aboove the knee |
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what are the types of venous outflow plethsmography?
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-impedance plesmographY(IPG)
-strain guage plesthmographY(SPG) -air plethsmography |
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collecting cuff
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pneumatic cuff placed around patients thigh
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DC coupling?
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aka direct current
-electrical voltage that is either positive or negative -current flow in only on direction -useful in evaluating very slow flow states |
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explain the technique for SPG/IPG venous test?
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-pneumatic cuff inflated to 50mmHg
-results in increase in calf volume -allow rise to continue for 2minutes -Rapidly deflate cuff -resulting decrease in calf volume recorded until volume returns to pretesting levels |
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explain venous strain guage plesthmographY?
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-may detect venous obstruction in lg veins above the knee
-extremely sensitive test -quantifies altered calf volume |
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explain the technique for SGP
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-silicon tube filled w/ mercury is wrapped around the calf w/ copper electrodes at both ends of the guage
-voltage applied across guage -calibration done at this point -cuff applied around the thigh, and inflated to 50mmHg -when the leg becomes distendeed w/ blood and the corrisponding circuference of the leg changes, voltage also changes |
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HOw is SGP interpreted?
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-max rise in tracing refects max. capacitance of the calf veins
-teh rate of venous outflow is reflected by the decline of teh tracing max-venous outflow -tracing should fall to the baseline within 3 seconds to be normal -if there is an upstream occlusion, calfs will not be able to emptly as quickly, so rate of outflow will be longer -results plotted agains a chart -increased resistance reduces voltage which is shown on a strip chart -as blood volume increases(due to venous outflow blockage), strip chart shows max rise in the tracing compared to the baseline. |
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what are the capabilities of impedence plethsmography/
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-detect thrombi in iliac, femoral, and popiteal veins
-highly sensitive and easily affected by other factors -measures volume changes -not sensitive to calf vein thrombus |
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what are some false positives w/ IPG?
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-post thrombotic syndrome w/ large collaterals
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explain the IPG test?
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-current conducted through the electrodes appled to the calf
-measures volume changes caused by changes in blood volume -changes in resistance are major causes for changes in impedance |
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ohm's law
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the expression of the releationship btw voltage, current and resistance in a circit
I=V/R |
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what are the advantages and limitations of venous reflux PPG?
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ADVANTAGES:
-requres less time -easier to perform LIMITATIONS: -numerous shortcomings -results often indeterminate |
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Explain PPG w/ incopetant venous valves( 2 ways)
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1. Calf volume is not reduced to to incompetant calf-veno motor pump
-PPG tracing oscillates up and down, but there is now lowering of the baseline 2. PPG trace lowers on a strip chart indicateing a decrease in volume, but tracing rapidly retruns to pre-exercise level. -indicates a return of valve volume via incopetent venous channels |
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explain the method for testing for PPG
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-warm room
-patient sitting on edge of stretcher -PPG trx applied cephalad to medial malleolus w/ double sided tape -allow system to equalibriate(steady baseline) -strip chart speed=5mm/sec -have patient plantarflex, and dorsiflex 5 times in 5 seconds -observe PPG during exercise and recovery period -stop test when PPG tracing achieves pre-exercise baseline level, reaches stable plateau, or 60 seconds elapses. -measure recovery time |
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Light reflective rheography
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-refinement of PPG
-added compartment of a thermistor which measures skin temperature -relies on the same principle where increased temperature=increased blood flow, and increased volume -produces the same type of results as PPG PITFALLS: -not specific -cannot reliably detect obstruction |
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air plethysmography(APG)
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-used to assess the presence and severity of venous reflux
-a 14 inch long, 5L capacity polyvynil chloroid air chamber surrounds patients leg from knee to ankle -a bag is placed btw patients leg and chamber for calibration -patient lies supine w/ legs elevated 45 degrees -cuff is connected to a pressure transducer, an amplifier and a recorder |
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technique for air plethsmography
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--inflate chamber to 6mmHg
-ask patient to stand w/ weight on opposite extremity -the change in volume from supine to erect results from venous filling -have patient stand on both legs and do 10 heel raises -EF and residual volume may be measured w/ this method |
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how is ejection fraction for air plethsmography calculated?
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-by taking the expelled volume after doing 10 heel raises and dividing it by the total venous volume x 100.
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Which vessels are interogated with the transtemporal probe w/ TCD testing? What is the normal flow direction of each of these vessels?
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ACA-away from transducer
MCA-toward PCA-toward |
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GIve the distance from the transducer, and velocites of the arteries demonstrated from the transtemoral view w/ TCD testing?
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ACA-60-80mm; 50 +/-11 cm/s
MCA-30-60mm 50 +/-12cm/s PCA-60-70mm 39 +/-10cm/s |
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Name the arteries interogated from the transforaminal view, and their flow direction?
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AKA suboccipital view
Vertebral=away Basilar=Away |
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Give the distance from the transducer and velocities of the arteries interogated using the suboccipital window for TCD?
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Vert-55-80mm; 38+/-10cm/s
Basilar-80-120mm; 41+/-10cm/ |
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Name the arteries and their flow directions using the transorbital window for TCD testing?
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Opthalmic-toward
Carotid siphen: supraclinoid-away Genu-bidirectional parasellar-toward |
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Name the flow velocities and distance from the transducer of the arteries interogated from the transorbital window with TCD?
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opthalmic-40-60mm; 21+-5cm/
carotid-65-70mm; no velocity given |
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Name the artery interogated using the submandibular window, and it's direction on Tcd?
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Distal cervical carotid artery: away
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What is the velocity, and distance from the submandibular window of the distal cervical carotid artery on TCD?
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45-70mm(usually 50)
30-34+/-9cm/s |
