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International audience; AimTo demonstrate that ultrasound screening of diabetic patients presenting with no cerebrovascular symptoms for evaluation of atheroma of the cervical arteries can be limited to the carotid arteries. Methods We retrospectively analyzed the results of cervical artery ultrasound imaging of diabetic patients with no cerebrovascular symptoms. This diabetic population was divided into two subpopulations according to whether or not the vertebral and subclavian artery findings were normal or abnormal. Results Of the 760 patients who fulfilled the criteria for study inclusion, the ultrasound imaging findings of the vertebral and subclavian arteries were normal in 712 cases. Review of the files of the 48 remaining patients showed that findings for either the vertebral or subclavian arteries did not lead to any changes in patient management because of associated risk factors, carotid atheroma or peripheral arterial disease. Conclusion A vascular risk evaluation in diabetic patients could include ultrasound imaging assessment for cervical artery atheroma and our data suggest that such an evaluation could be focused solely on the carotid arteries.

Thrombi within the carotid artery usually occur in vessels with severe atherosclerotic lesions and may embolize to cause TIAs and ischemic brain infarctions. The risk factors and potential causes for carotid artery thrombus formation in the absence of atherosclerosis are currently only speculative (e.g., embolic occlusion from a cardiac source).1 Furthermore, a focal adherent thrombus involving the CCA is even more exceptional because of the rarity of severe atherosclerotic disease in this large and nonturbulent vessel.1,2 A thrombus lodged in the CCA has been reported in only a very few cases in the literature.2 We present two patients with a focal adherent thrombus in the CCA diagnosed by ultrasonography and confirmed by neuroimaging. The aim of this work is to investigate the ultrasonographic features of this very uncommon finding in young stroke patients.

Carotid dissections often go undetected or are confused with an arteriosclerotic cause; in fact, they rarely require surgical treatment. Twenty-eight extracranial carotid dissections (in 25 patients) without direct cervical traumatism were explored successively by pulsed and duplex Doppler ultrasonography complemented in 10 cases by color Doppler flow imaging and secondarily in all cases by arteriography. Pulsed Doppler (DMS Angiodop 481 with 4 and 8 MHz probes) found severe hemodynamic signs in 93% of cases: 6 occlusions, 11 generally extensive or high tight stenoses and 9 significant slowdowns in carotid and ophthalmic artery circulation. For the same internal carotid artery, duplex Doppler (Ultramark 4 or Sonedap 40 with 5, 7.5 and 10 MHz probes) initially showed 5 occlusions and 2 stenoses (4 with fusiform features), 2 double canal images, 8 internal carotid arteries with tubular features (internal caliber less than or equal to 2 mm) and 2 segmental ectasias. There were only 3 other lesions with arteriosclerotic features, 2 of which were minor. Duplex imaging was thus suggestive in 57% of cases. Color Doppler flow imaging enabled precise visualization of these features, better analysis of occlusions and clear detection of 2 other false canal images. After 2 years of follow-up, Doppler ultrasound showed recanalization in 47% of cases with no anticoagulant complications. These combined ultrasonic explorations would thus appear to be useful for early diagnosis of carotid dissections, for guiding arteriography and for facilitating the monitoring of patients under anticoagulant.

Noninvasive diagnosis of vertebral artery disease is difficult, but the combined use of Doppler ultrasonography and dynamic radionuclide studies, with measurement of the carotid-basilar delay (CBD), increases the sensitivity and can indicate the level (cervical or distal) of the lesion. Forty patients with cerebrovascular disease were studied by continuous wave Doppler and CBD and the results were compared with vertebral angiograms. The mean normal CBD value was determined for a control group of 18 patients. Sensitivity and specificity were 87.5 per cent and 75 per cent, respectively, for Doppler alone, and 100 per cent and 60 per cent for combined Doppler and CBD.

Symptomatic stenoses of the middle cerebral artery (MCA) are not uncommon, although Corston observed the occurrence of stroke in 24% of patients with MCA stenoses during a 6-year follow-up study. We tried to use transcranial Doppler (TCD) sonography for the detection and evaluation of MCA stenoses. Intra-arterial angiography demonstrated 16 MCA stenoses of more than 30% diameter reduction in 15 patients (14 atheromatous stenoses, 2 dysplasias). Severe associated lesions were present in 2 cases (more than 75% internal carotid artery stenosis). These 15 patients with MCA stenosis were examined with TCD in a blind study. A Doppler signal from the MCA was obtained through the temporal bone and was recognized on the result of common carotid artery compression test. We ascertained MCA stenosis when TCD demonstrated 1) segmental flow acceleration with peak systolic frequency of more than 3 KHz with or without high energy low frequency direct or reverse components; or 2) segmental increase in systolic peak frequency of more than 20%. Using these criteria, we confirmed through TCD the presence of MCA stenosis in nine out of 12 cases with diameter reduction of at least 50%, and one among four cases with less than 50% diameter reduction. Although our results are consistent with Aaslid and von Reutern's figures, methodological problems and diagnostic criteria have to be improved. Nevertheless, TCD seems to be a useful tool for the detection of stenosis with at least 50% diameter reduction, where it proved to offer a 75% sensitivity. Further studies are necessary to improve sensitivity and specificity.

In a retrospective study about the seven past years in our Hospital Center, we found that the number of X-ray venographies increased strongly from year to year until non-invasive examinations (Doppler and plethysmography and Real-time B-mode sonography) were widely used with a high sensitivity and specificity level. A new diagnostic algorhythm was then introduced in the clinical practice, X-ray venography being required mainly when an invasive treatment (thrombectomy, thrombolysis, vena cava interruption...) was planed, but not for the positive diagnosis. Thereafter, the number of X-ray venographies decreased. In that way, the cost of the diagnosis was significantly reduced as were risks and discomfort for the patient.

The purpose of this study was to assess the value of duplex scanning and continuous wave Doppler velocimetry in the diagnosis and follow-up of ICA dissections. Between 1975 and 1988, 20 patients (11 women and 9 men; mean age 45 years) were admitted to the University Hospital of Angers for dissection of the ICA confirmed by angiography. The dissections were unrelated to direct cervical injury and were unilateral in 18 cases and bilateral in 2 cases. Six patients experienced transient cerebral ischaemic accidents (later completed in 2 cases) and 2 patients merely complained of ocular disorders of sympathetic origin. Fourteen patients were treated with heparin. All patients were examined by continuous wave Doppler ultrasound followed by duplex scanning. These examinations were performed 10 days on average before angiography. Continuous wave Doppler revealed signs of obstruction of the ICA in 95% of the cases: occlusion in 4 cases, tight stenosis in 13 cases and marked slowing of blood flow in the carotid and ophthalmic arteries in 4 cases. The acoustic signs of high or extensive ICA stenosis with reduced or retrograde ophthalmic artery blood flow were fairly suggestive of dissection. These results were completed by mode B which showed signs of dissection in 61% of the cases (tapering stenosis or occlusion, tubular ICA, separation of the vascular walls on rare occasions) and excluded atheromatous lesions in 81% of the patients. The tubular ICA image being non-specific was interpreted in relation to the clinical context and haemodynamic data, after discussion and exclusion of fibromuscular dysplasia, intracranial carotid stenosis causing severe reduction of blood flow and the exceptional hypoplasia of the ICA.(ABSTRACT TRUNCATED AT 250 WORDS)

Velocimetric exploration by continuous emission Doppler is still essential for non-invasive evaluation of vertebral circulation but it does not provide morphologic data. Results were compared of exploration with combined continuous emission Doppler and a Duplex examination (sectorial scanning ultrasound imaging coupled with pulsed emission Doppler) and data from arteriography of 186 vertebral arteries in patients, mean age 57 years, admitted for exploration of a cerebral ischemic accident or a cervical murmur. The Duplex examination allowed identification of proximal segment (VI) in 98% of permeable vertebral arteries. The ostium of the vertebral artery was more difficult to visualize because of possible tortuosities, of sometimes a too posterior or intrathoracic localization or of a short neck. Nevertheless the vertebral ostium was identified in 78% of cases on the right and 48% on the left. The Duplex examination demonstrated sensitivity of 72% and specificity of 98% for detection of proximal stenosis of vertebral artery, and its sensitivity was therefore twice as sensitive as continuous emission Doppler for detection of stenoses of less than 50%. The Duplex examination should complete data from continuous emission Doppler by providing an evaluation of vertebral artery diameter and information on presence and characters of an elongation or stenosis. In this way, 9 atheromatous plaques not identified on arteriography were detected by ultrasound imaging. Similarly, the Duplex examination is particularly useful for identification of a hypoplastic vertebral artery, to distinguish the specific lesions of the subclavian artery from those extending onto vertebral ostium, and to characterize ostial lesions when these are accessible to examination.(ABSTRACT TRUNCATED AT 250 WORDS)

Results and correlation with arteriographic findings in 25 cases. The methodological criteria essential to the reliability of this examination are described, as well as the special conditions of recording which may influence interpretation. The respective values for systolic and diastolic circulatory rates obtained on ultrasound curves led the authors to classify the results into five groups. There was satisfactory correlation between the latter and the anatomical data provided by arteriography of the vertebral arteries. Such a quantitative approach provides an assessment of the functionally normal or pathological state of the vertebral arteries and of circulatory assymetry.

Vertebrobasilar ischemic disease cannot be adequately explored by echo-Doppler ultrasonic investigating procedures, since they do not permit the study of the intracranial arteries. The transcranial pulsed Doppler (2 MHZ) velocity detection method developed by R. Aaslid now offers such possibilities, although it has not yet been validated in this field. The authors relate their experience and methodological criteria (patient's position, deepness of access, flow direction, response to compression tests). They conducted 2 studies, one bearing on the detection of 14 cases of 75% stenosis of the superior segment, or of arteriographically-confirmed endocranial vertebral/basilar artery occlusion; the other one was concerned with assessing the basilar hemodynamic consequences of vertebral-subclavian steal syndromes. Out of 17 steal syndrome cases, of which 5 were symptomatic (4 pre-steal cases, 7 permanent, 6 intermittent), basilar flow determined spontaneously or following postischemic hyperemic test of the upper limb, was moderately changed in 30% of cases. Transcranial pulsed Doppler ultrasonic examination could be recommended in addition to the regular echo-Doppler velocity detection test, and thus contribute to exploring and monitoring transient or full-blown ischemic accidents of the vertebrobasilar circulation, in expectation of medical, surgical or angioplastic management.

The sonographic diagnosis of deep venous thrombosis must be made up of a functional continuous wave Doppler study of the whole deep venous system of the limbs, including leg veins, as well as saphenous veins. Then, high resolution B-mode real time sonography is used for the detection of direct (echogenic thrombus) or indirect (incompressible vein) signs of thrombosis. This noninvasive approach offers a good sensitivity (about 96%) and a high level of specificity (about 98%). Moreover, B-mode sonography can ensure the differential diagnosis (hematoma, extrinsic compression...) in most cases. So, X-Ray venography is required only when an interventional therapy is planned (thrombectomy, fibrinolysis, inferior vena cava interruption...), or when the noninvasive techniques are not able to show the upper limit of the thrombosis (especially for iliac veins or inferior vena cava), or when there is still a doubt about deep venous thrombosis. Therefore, the number of X Ray venographies can be consistently reduced, thus decreasing both cost and risks.

The authors have analyzed by transcranial pulsed Doppler 50 patients with one or two obstructions of the internal carotid artery, divided in three groups: 19 tight stenoses, 23 obstructions and 8 bilateral tight stenoses. The haemodynamic consequences of these carotid obstructions was evaluated from the results of velocity in the intracerebral arteries, the resistance index and the pulsatility compared to a reference artery (PTI). The PTI seems the most sensitive. Compared with the resistance index, it permits to better define the patients prone to be the victims of a haemodynamic cerebro-vascular accident, and seems indicated before carotid surgery is contemplated.

The validity of transcranial Doppler (tD) was evaluated for the identification of stenoses of the middle cerebral artery (MCA). Twenty patients with atheromatous stenosis of the proximal MCA of more than 30% (3 of these cases with stenosis of more that 75%) had repeated transcranial Doppler between 1975 and 1987 and conventional angiography. No patient had carotid stenosis nor embolus-producing cardiopathy. Ten patients had had infarcts or transient ischemic attacks (symptomatic group). Ten patients were asymptomatic (asymptomatic group). Cerebral infarcts in the MCA territory occurred in 1 patient of each group and 1 additional patient in each group had an infarct in another territory. Follow-up was possible in 15 patients. The stenosis remained unchanged in 14, occlusion occurred in 1. The results of transcranial Doppler were compared to those of angiograms in this series and in an additional series of 40 patients who had had a normal angiogram. Sensitivity of transcranial Doppler was 60% (75% when stenosis was over 50%). Specificity was 95%. Comparison with angiography findings showed, among causes of failure of tD, analysis of the artery over too short a segment or kinked artery of very long stenoses, or too decreased blood flow. The failure rate of tD due to failure of bone penetration by ultrasounds was 5%. This new reproducible, non-invasive method appears to be able to detect MCA stenoses of 50% or more and help in follow-up.