Ultrasound Doppler

The Combined Lysis of Thrombus in Brain Ischemia Using Transcranial Ultrasound and Systemic rt-PA (CLOTBUST) study was a phase II randomized trial which compared continuous transcranial Doppler ultrasound insonation, in subjects with ultrasound evidence of MCA occlusion being given IV rt-PA, to sham insona-tion. ° There was an increased rate of arterial recanalization with the continuous insonation (49% vs. 30%, p = 0.03) and no increased risk of sICH. 

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

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. 

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. 

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). 

Evans, D.H, and N. McDicken Doppler Ultrasound Physics, Instrumentation, and Signal Processing. 2nd Edition. John Wiley Sons, Inc., New York. NY, 2000 Harness. J.K. Ultrasound in Surgical Practice Basic Principles and Clinical Applications, John Wiley Sons, Inc., New York, NY, 1999. 

Cohen LS, Escobar PF, Scharm C, Glimco B, Fishman DA. Three-dimensional power Doppler ultrasound improves the diagnostic accuracy for ovarian cancer prediction. Gynecol Oncol 2001 82(l) 40-48. 

The association between hyperlipidaemia and ED has been studied in apparently healthy men who complained of ED (13), Over 60% had hyperlipidaemia and 90% of these had evidence of penile arterial disease using Doppler ultrasound studies, Diabetes is commonly associated with ED with a prevalence of 50% (range 27-70% depending on age and disease severity). The onset of ED usually occurs within the first 10 years of the diagnosis of diabetes (14). 

Subtotal stenoses greatly reduce post-stenotic flow and are called pseudoocclusions, since they are difficult to differentiate from true occlusions even with Doppler ultrasound (without the use of ultrasound contrast media). There are only a few studies on this problem with limited numbers of patients. In the majority of cases, CE-MRA could differentiate stenosis from occlusion (Friese et al. 2001a Remonda et al. 2002) (Fig. 5.16). In these... 

Fig. 5.19a,b. Multiple intracranial stenoses TOF-MRA (a,b) with Doppler ultrasound correlation. High grade stenosis of left MCA (Ml) was confirmed (>400 cm/s), suspected right M2 stenosis was estimated as mild by ultrasound and a left PCA stenosis was suspected only on MRA... 

Until now there have been very limited data on the use of hypothermia in moderate stroke. Naritomi and co-workers reported their findings of seven patients treated with hypothermia within the first 6 h after stroke onset (54). Inclusion criteria for this study were embolic occlusion of the MCA proven with angiography or by Doppler ultrasound. The treatment protocol was similar to the others mentioned in the preceding. Six of the seven patients in this group were able to walk without support at the time of discharge. All of these six patients had either a small infarction or infarction without any mass effect on CT during or after hypothermic therapy. 

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. 

Indirect assessment of perfusion reserve can be achieved by using transcranial Doppler ultrasound, single-photon emission CT, PET, dynamic CT or functional MRI to measure... 

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... 

Possible indications for transcranial Doppler ultrasound in routine clinical practice (Babikian etat 1997 Molloy and Markus 1999 Alexandrov etaf 2004 Kim etat 2005 Dittrich et at 2006 Markus 2006) include ... 

Markus HS (1999). Transcranial Doppler ultrasound. Journal of Neurology, Neurosurgery and Psychiatry 67 135-137... 

Markus HS, Droste DW, Brown MM (1994). Detection of asymptomatic cerebral embolic signals with Doppler ultrasound. Lancet 343 1011-1012... 

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... 

Droste DW, Kriete JU, Stypmann J et al (1999). Contrast transcranial Doppler ultrasound in the detection of right-to-left shunts comparison of different procedures and different procedures and different contrast agents. Stroke 30 f 827-1832... 

Asymptomatic embolization detected by Doppler ultrasound predicts stroke risk in symptomatic carotid artery stenosis. 

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