Doppler, carotid

Suwanwela N, Can U, Furie KL, Southern JF, Macdonald NR, Ogilvy CS, Hansen CJ, Buonanno FS, Abbott WM, Koroshetz WJ, Kistler JR Carotid Doppler ultrasound criteria for internal carotid artery stenosis based on residual lumen diameter calculated from en bloc carotid endarterectomy specimens. Stroke 1996 27(11) 1965-1969. 

Carotid Doppler studies will determine whether the patient has a high degree of stenosis in the carotid arteries supplying blood to the brain (extracranial disease). 

Carotid Doppler— A technique that provides information about the presence and severity of atherosclerosis of the carotid artery, using noninvasive sound wave technology. 

The GP Ilb-IIIa complex inhibitor Tirofiban has been used as an adjunct to thrombolysis in a number of small case series reports." A small transcranial Doppler (TCD) study suggests that it reduces microembolization from unstable carotid plaque." In an open pilot smdy, Tirohban administered within 9 hours after stroke onset blocked the conversion of ischemic penumbra to mature infarction." A phase III study (SETIS) has started recruiting patients to investigate its efficacy versus aspirin within the 6-hour window. 

Markus H, Mac Kinnon A. Asymptomatic embolization detected by Doppler ultrasound predicts stroke risk in symptomatic carotid artery stenosis. Stroke 2005 36 971-975. 

Ultrasound Carotid non-invasive studies and transcranial Doppler... 

Patel SG, Collie DA, Wardlaw JM, Lewis SC, Wright AR, Gibson RJ, Sellar RJ. Outcome, observer reliability, and patient preferences if CTA, MRA, or Doppler ultrasound were used, individually or together, instead of digital subtraction angiography before carotid endarterectomy. J Neurol Neurosurg Psychiatry 2002 73(l) 21-28. 

Polak IF, Dobkin GR, O Leary DH, Wang AM, Cutler SS. Internal carotid artery stenosis accuracy and reproducibility of color-Doppler-assisted duplex imaging. Radiology 1989 173(3) 793-798. 

Steinke W, Kloetzsch C, Hennerici M. Carotid artery disease assessed by color Doppler flow imaging correlation with standard Doppler sonography and angiography. AJR Am J... 

Markus HS, Droste DW, Kaps M, Larrue V, Lees KR, Siebler M, Ringelstein EB. Dual antiplatelet therapy with clopidogrel and aspirin in s3miptomatic carotid stenosis evaluated using doppler embolic signal detection the Clopidogrel and Aspirin for Reduction of Emboli in Symptomatic Carotid Stenosis (CARESS) trial. Circulation 2005 lll(17) 2233-2240. 

Echo-Doppler of carotid artery As indicated by clinical features... 

In addition to coronary sclerosis, evidence is accumulating that high Lp(a) levels may be important in the development of cerebrovascular and peripheral arterial disease, as well (J6, T8, U2). Lp(a) levels not only correlated well with clinical endpoints such as transient ischemic attack and cerebral infarction, but also were associated with the extent and severity of carotid atherosclerosis, as assessed by bidirectional Doppler ultrasound (K23, M33, Z2). 

Vos JA, van den BergJC, Ernst SM, et al. Carotid angioplasty and stent placement comparison of transcranial Doppler US data and clinical outcome with and without filtering cerebral protection devices in 509 patients. Radiology 2005 234 493 -99,... 

Pujia A, Rubba P Spencer M P Prevalence of extracranial carotid artery disease detectable by echo-Doppler in an elderly population. Stroke 1992 23 818-822. 

Fig. 7. Schematic diagram of the canine femoral artery copper coil model of thrombolysis. A thrombogenic copper coil is advanced to either femoral artery via the left carotid artery. By virtue of the favorable anatomical angles of attachment, a hollow polyurethane catheter advanced down the left carotid artery nearly always enters the descending aorta, and with further advancement, into either femoral artery without fluoroscopic guidance. A flexible, Teflon-coated guidewire is then inserted through the hollow catheter and the latter is removed. A copper coil is then slipped over the guidewire and advanced to the femoral artery (see inset). Femoral artery flow velocity is measured directly and continuously with a Doppler flow probe placed just proximal to the thrombogenic coil and distal to a prominent sidebranch, which is left patent to dissipate any dead space between the coil and the next proximal sidebranch. Femoral artery blood flow declines progressively to total occlusion over the next 10-12 mm after coil insertion.

A 70-year-old woman with a history of mastectomy developed syncope which lasted a few seconds. She had taken tamoxifen 10 mg bd for 10 years and had no history of allergic reactions. Doppler ultrasound showed aortic stenosis and coronary angiography was performed using 150 ml of iopromide (a non-ionic contrast medium, iodine 370 mg/ml). She had visual hallucinations (spiders on the wall, moving curtains) 30 minutes after the injection of iopromide. The symptoms resolved 72 hours later without any specific treatment. Neurological and psychiatric examinations were normal, as were brain MRI and Doppler ultrasound of the carotid and vertebral arteries. 

Kizer JR, Devereux RB (2005). Clinical practice. Patent foramen ovale in young adults with unexplained stroke. New England Journal of Medicine 353 2361-2372 Koennecke H, Mast H, Trocio SH et al (1998). Frequency and determinants of microembolic signals on transcranial Doppler in unselected patients with acute carotid territory ischemia. A prospective study. Cerebrovascular Diseases 8 107-112... 

Schmahmann JD (2003). Vascular syndromes of the thalamus. Stroke 34 2264-2278 Schulz UG, Rothwell PM (2001). Major variation in carotid bifurcation anatomy a possible risk factor for plaque development Stroke 32 2522-2529 Scott BL, Jankovic J (1996). Delayed-onset progressive movement disorders after static brain lesions. Neurology 46 68-74 Wardlaw JM, Merrick MV, Ferrington CM et al. (1996). Comparison of a simple isotope method of predicting likely middle cerebral artery occlusion with transcranial Doppler ultrasound in acute ischaemic stroke. Cerebrovascular Diseases 6 32-39 Wardlaw JM, Lewsi SC, Dennis MS etal. (1999). Is it reasonable to assume a particular embolic source from the type of stroke Cerebrovascular Diseases 9(Supp 1) 14... 

Fig. 12.3. A color-flow Doppler ultrasourid of the carotid bifurcatlori showirig a plaque (arrow) at the origiri of the Iriterrial carotid artery (ICA) arid the resulting stenosis. ECA, external carotid artery CCA, common carotid artery. (See the color plate section.)...

Despite these limitations, duplex sonography is a remarkably quick and simple investigation in experienced hands, and it is neither unpleasant nor risky. Very rarely, the pressure of the Doppler probe on the carotid bifurcation can dislodge thrombus, or cause enough carotid sinus stimulation to lead to bradycardia or hypotension (Rosario et al. 1987 Friedman 1990). The same conceivably applies to the various arterial compression maneuvres that may be carried out during transcranial Doppler, and any such compression should be avoided in patients who may have carotid bifurcation disease. 

Gaitini D, Soudack M (2005). Diagnosing carotid stenosis by Doppler sonography state of the art. Journal of Ultrasound Medicine 24 1127-1136... 

Can simple clinical features be used to identify patients with severe carotid stenosis on Doppler ultrasound Journal of Neurology, Neurosurgery and Psychiatry 66 16-19... 

Stump pressure and transcranial Doppler for predicting shunting in carotid endarterectomy. European Journal of Vascular Endovascular Surgery 25 164-167... 

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