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Two groups of subjects, matched for age, were studied. The first group consisted of 190 healthy subjects, the second, of 60 patients with vertebrobasilar transient ischemic attacks (TIAs), 22 of whom underwent angiography. After it was ascertained that the findings from continuous-wave (cw) Doppler of carotid and vertebral arteries, performed in the standard position, were normal, the examination was then done in De Kleyn's position, the velocity signal being detected at the mastoidal slopes. The abnormal findings were classified into two groups: "loss of diastolic velocity signal" and "absence of velocity signal." In the control group, changes of flow were detected in 6.31%, whereas in the group of patients abnormal Doppler parameters were detected in 33.33%. None of the patients who were submitted to angiography showed abnormal hemodynamic findings. The authors suggest that the detection of the velocity signal of the vertebral arteries in De Kleyn's position could be of help in revealing conditions that could cause, in time, signs and/or symptoms of vertebrobasilar insufficiency in subjects with possible asymptomatic anomalies of the circle of Willis.

Background and Purpose-The North American and the European Carotid Endarterectomy Trials demonstrated a significant benefit of surgery in preventing stroke for patients with symptomatic hemodynamically significant internal carotid artery (ICA) stenosis. Because the 3 angiographic methods of measuring carotid stenosis provide discrepant results, the indication for surgery depends on the method used for the evaluation of the angiogram. The goal of this study was to verify whether color duplex scanning of the ophthalmic artery alone might be reliable for detection of the extracranial hemodynamically significant ICA stenosis. Methods-Three groups of patients (351 total patients) with transient ischemic attack or minor stroke referred for possible carotid endarterectomy were examined by means of color duplex scanning of the ICA, transcranial Doppler, color duplex scanning of the ophthalmic artery, and angiography of the ICA. Results-In the first group (nϭ31) the comparison of findings from each method and the direct measurement of the residual lumen of plaque removed "en bloc" showed that the findings of the ophthalmic artery color duplex scanning, subdivided into 5 categories-NP (normal positive), LP (low positive), NF (no flow), REV (reverse flow), PP (pathological positive)-were associated with the best overall agreement (96.7%). The accuracy of the various categories of the ophthalmic artery color duplex scanning signals was studied in the second group of patients (nϭ200). The results pointed out that all but low positive categories were associated with high diagnostic accuracy. Finally, the results obtained in the third group (nϭ120) showed that a significant increase in the specificity of the low positive signal could be obtained by processing this signal in terms of pulsatility index and of transmission of pulsatility index. Conclusions-Our results suggest that the diagnostic capacity of color duplex scanning for the detection of ICA critical stenosis can be appropriately increased if it is performed also at the level of the ophthalmic artery and if the Doppler signals are processed on the basis of criteria we applied. (Stroke. 1999;30:821-826.)

By intrabrachial artery injections of a bolus of human albumin microspheres labeled with 99mTc in patients with primary or secondary Raynaud's phenomenon (RP) and in a group of healthy volunteers, the authors developed a method of detecting the patency rate of arteriovenous anastomoses (AVA) in the hand, after local heat and cold stimulation, by quantifying the radioactivity of the lungs expressed as a percentage of an intravenously injected radionuclide dose. With strain gauge plethysmography, simultaneous changes in the digital total (DTF) flow were also measured. After exposure of fingers to cold, 25 of 26 subjects had a clear reduction in both DTF and the AVA patency rate (APR) in comparison with the corresponding heat values. The RP patients, in particular, showed a statistically significant reduction in DTF (P less than 0.001) and in APR (P less than 0.001). These results appear to be consistent with the onset of critically reduced patency of the AVA of the hand during the ischemic phase of RP.