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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.

Vertebrobasilar intracranial stenoses seem to carry a higher risk of brain stem ischemia than proximal vertebral artery stenoses. Our aim was to assess the value of transcranial Doppler sonography versus angiography in detecting and quantifying these intracranial stenoses. All consecutive patients who underwent transcranial Doppler sonography prior to angiography from 1989 to 1994 and whose sono-grams showed a stenosis of greater than 50% of one vertebral artery (21 cases) or of the basilar artery (eight cases) were included in the study. These patients were compared with 60 other consecutive stroke patients studied via transcranial Doppler sonography prior to normal vertebrobasilar angiography. The transcranial Doppler sonographic criteria for stenosis were a peak systolic frequency shift greater than 2 KHz. A tight stenosis was identified by this pattern combined with direct and reverse low frequencies of high spectrum energy. The sensitivity of transcranial Doppler sonography using a peak systolic frequency shift in diagnosing stenoses reached 80% and its specificity was 97% if only atheromatous stenoses were considered. The main diagnostic failures concerned bilateral stenoses or contralateral occlusion, tandem lesions, and upper basilar artery stenosis. Transcranial Doppler sonography underestimated the degree of stenosis compared to angiography in 55% of the cases. We conclude that transcranial Doppler sonography is accurate in recognizing a stenosed vessel in the intracranial vertebrobasilar circulation, but if this finding will alter therapy, the examination must be complemented by magnetic resonance angiography.

The relationship between intracranial pressure or cerebral perfusion pressure (CPP), cerebral blood flow, and brain energy failure is unpredictable throughout the development of acute intracranial hypertension. The purpose of the present study was to correlate intracranial pressure with cerebral blood flow velocities and brain energy metabolism in adult rabbits. The acute intracranial hypertension was achieved by pressure transmission. Transcranial Doppler wave-forms were obtained from the basilar artery for monitoring cerebral blood flow velocities. 31P-Magnetic resonance spectroscopy was used to assess brain energy metabolism. The diastolic blood flow velocity began to decrease significantly (34.5%) when the intracranial pressure was equal to half the diastolic arterial pressure for a CPP of 36 +/- 18 mmHg. Circulatory cerebral resistances increased significantly (55%) for the same value of CPP. Diastolic frequency was near zero when intracranial pressure approached diastolic arterial pressure (51 +/- 12 mmHg), corresponding to a CPP of 30 +/- 15 mmHg. At the same time, only a tendency for brain energy metabolism to decrease was observed. Consequently, transcranial Doppler sonography could be proposed for the follow-up of intracranial hypertension. Magnetic resonance spectroscopy could help to monitor these patients and could be especially proposed in case of high intracranial pressure (near diastolic arterial pressure). The joint use of these two methods would help in making appropriate therapeutic decision in humans.

The effect of an intravenous injection of thiopental on middle cerebral artery blood velocities was assessed by transcranial pulsed Doppler monitoring in 20 children: ten head-injured patients and ten control subjects. Thiopental induced a moderate but immediate decrease of middle cerebral artery blood velocities in both groups; this variation was significant (P

The reliability of duplex scanning (DS) for the diagnosis of internal carotid artery dissections (ICAD) is not clear.Nine DS signs known to be suggestive for the diagnosis of ICAD were compared between 70 patients with ICAD and 70 matched patients without dissection.Visible internal tapering occlusion, regular eccentric narrowing channel, ectasia beyond the carotid bulb, resistive index asymmetry, blood flow slowdown, ophthalmic artery blood flow inversion, and biphasic flow are more frequent in cases than in controls (p0.001). Atheroma plaques were absent in 80% of ICAD. When DS direct signs and hemodynamic signs were studied, sensitivity was 90% and specificity 60%.Diagnosis of ICAD by DS could be improved if direct signs were combined with hemodynamic signs, giving a high sensitivity and a rather good specificity.

Transcranial pulsed Doppler sonography with or without imagery is used in the acute phase of ischemic stroke in order to define stroke mechanism and intracranial hemodynamic consequences.This non-invasive low-cost investigation can be undertaken rapidly, within 10 minutes if guided by focal symptomatology. It detects middle cerebral artery stenosis inor=50 p. cent of cases with a sensitivity between 75 and 90 p. cent, comparatively with conventional angiography, and middle cerebral artery occlusion with 90 p. cent sensitivity. When a temporal acoustic window is lacking, intravenous injection of a contrast agent allows good visualization of the intracranial vessels and the circle of Willis, in two-third of cases. Moreover, transcranial Doppler data have good prognostic value and facilitate analysis of recanalization after thrombolytic therapy.Beside its diagnostic and prognostic interest, transcranial Doppler sonography using a 2 MHz frequency appears to have therapeutic impact by favoring the thrombolysis process. Future developments may include early and prolonged insonation of patients suffering from stroke.

We report a case of cerebral deep venous thrombosis that manifested clinically by a pseudobulbar syndrome with major trismus, abnormal movements and static cerebellar syndrome. To our knowledge, only three other cases of deep cerebral venous thrombosis associated with cerebellar or pseudobulbar syndrome have been published since 1985. The relatively good prognosis in our patient could be explained by the partially intact internal cerebral veins as well as use of early anticoagulant therapy. There was a spontaneous hyperdensity of the falx cerebri and the tentorium cerebelli on the brain CT scan, an aspect highly contributive to diagnosis. This hyperdensity of the falx cerebri was found in 19 out of 22 cases of deep venous thrombosis detailed in the literature.

The cardiogenic origin of stroke is often established on the basis of documented arrhythmia, computed tomographic evidence of cerebral ischemia, duplex Doppler findings ruling out an atheromatous carotid origin, and sometimes visualization of an intracavitary thrombus at transesophageal echocardiography. In case of a large thrombus as observed in our present patient, duplex Doppler provides an important means of visualizing the thrombus despite the lack of a parietal lesions suggestive of atheromatosis.

Carotid stenosis is the most frequently factor involved in stroke. The diagnosis of these lesions in routinely based on ultrasonic examination which allows to detect the carotid stenoses which were essentially atheromatous. B-mode evaluates the fine echostructure of plaques and Doppler helps to quantify the degree of stenosis using direct and indirect hemodynamic criteria. Echography with the help of color Doppler imaging identifies the site of stenosis in order to determine the degree of stenosis as a percentage of normal carotid area. Moreover echography is an essential method to appreciate the surface as well as the echostructure of the carotid lesion which have to be taking into account for a well-adapted therapy. The maximal velocities determined at the tight site of the lesion, the spectral changes downstream the stenosis and the hemodynamic changes observed upstream and downsteam of the carotid stenosis allow a precise quantification of this stenosis. The information obtained using sonographic methods (including 2 direct hemodynamic criteria, 2 indirect hemodynamic criteria and, if possible, a B-mode assessment of the area) are essential to appreciate the neurological risk in these patients.

To study color Doppler imaging in orbital vessels, especially para-optic short ciliary arteries, in patients with vascular glaucoma.Twenty vascular normal or moderate elevated pressure glaucoma patients (6 with bilateral glaucoma, 9 with unilateral glaucoma et 5 with asymmetric glaucoma) underwent a color Doppler imaging (Accusson 128XP) in orbital arteries: common carotid, ophthalmic artery, central retinal artery, short para-optic ciliary arteries. Systolic and diastolic blood flow velocities were measured, and resistance index of Pourcelot and ratios between different parameters were calculated.In patients with unilateral glaucoma, ratios of systolic velocities between para-optic ciliary artery and common carotid, and ratio of Pourcelot index between para-optic ciliary artery and ophthalmic artery were increased in glaucomatous eyes. And Pourcelot index were statistically significant increased in all glaucomatous patients of the study compared with normal subjects.Comparison of Pourcelot index and ratios between parameters makes color Doppler imaging more reliable, especially when analyse short para-optic ciliary arteries, which vascularize optic nerve. In these arteries Pourcelot index was increased in vascular glaucoma patients. Vascular risk factor should be taken into consideration in this form of glaucoma.

The development of ultrasonography in vascular applications has entailed research of ultrasound parameters leading to precise the diagnosis and quantification of carotid lesions in routine. The use of recent colour Doppler imaging techniques (velocity or power encoding) is recommended as they allow a better definition of the lesions and recesses. At present, features of plaque that could be related to increased incidence of stroke are: echogenicity, with a more frequent observation of anechoic or hypoechoic lesions in the case of clinical signs; texture, with frequent haemorrhage; surface contour, with a high rate of ulcerations which were accompanied by stroke; plaque motion, with a significant alteration in plaque motility in symptomatic patients; progression or regression in size, with a faster progression of anechoic and hypoechoic plaques; an increase in plaque volume is associated with a greater risk of stroke; a significant relationship between the presence of "ulcers" and embolic activity. The quantification of stenosis degree could be made using velocity criteria and/or morphological criteria. Velocity criteria could be obtained at the site of the stenosis (direct criteria) or downstream the carotid stenosis using Duplex systems. Morphological criteria could be obtained using B-mode imaging or colour Doppler but this quantification remains difficult in case of diffuse carotid stenoses or very severe stenoses.

OBJECTIVES—To compare the diagnosis and prognosis of extracranial versus intracranial vertebral artery dissections without intracerebral haemorrhage. METHODS—Twenty two vertebral artery dissections were defined by intra-arterial angiography and classified in two groups: group 1,nine extracranial dissections (seven patients) and group 2, 13intracranial dissections (nine patients), involving the basilar artery in five cases. Bilateral dissections were found in 38% of the population. Before angiography, all the patients had been investigated by continuous wave Doppler, colour coded Doppler, and transcranial Doppler. Mean follow up was 44months. RESULTS—The two most important symptoms of both dissections (81% of patients) were unbearable pain preceding stroke and progressive onset of stroke within a few hours. Severe ultrasonic abnormalities were present in 94% of the patients whereas specific ultrasonic signs (segmental dilation with eccentric channel) were rare (19%) in both groups. Major strokes and brainstem strokes represented respectively 67% and 78% in intracranial versus 43% and 29% in extracranial dissections. Severe sequelae (permanent disabling motor or cerebellar deficit) were more often associated with intracranial (44%) than with extracranial dissections (14%). No recurrence of dissection and no cerebral haemorrhage were found under heparin. Significant factors of poor outcome (P< 0.05) were the initial severity of the stroke and the bilateral location of dissections. CONCLUSION—The combination of a pain and a progressive onset of the stroke, corroborated by ultrasonic findings, could have helped to recognise most of these types of dissections. Intracranial dissections have a poorer prognosis than extracranial dissections.

After 6 years of experience, Spencer and colleagues described the detection of embolus signals as height intensity transient signals (HITS) within Doppler flow spectrum from intracranial vessels. These signals (gaseous or materials) are recorded in many situations such as cardiac prosthetic valves, atrial fibrillation, carotid stenosis, carotid surgery or angioplasty. The clinical value is not well known: neurological impairment associated with brain lesions is described in case of cardiac prosthetic valves. The observation of HITS in carotid stenosis is associated with an increased risk of stroke. The detection of HITS offers a new orientation in studying stroke but some technical and/or clinical difficulties have to be solved.

We undertook a prospective double-blind study of 128 carotid artery bifurcations using colour Doppler and duplex sonography and angiography. Sixty-four patients with cerebrovascular events were admitted for angiography. All underwent sonography within 24 h of angiography. Standard duplex sonography and colour Doppler imaging without spectral analysis were performed, on the same device, by two sonographers, using defined morphological and haemodynamic criteria. Digital radiological data on vessel diameter were interpreted independently by two radiologists. The two sonographic methods gave similar grading of stenosis, compared to angiography, with an accuracy ranging from 96% in severe to 83% in minor stenoses. Colour Doppler studies gave better area measurements than standard duplex sonography, except for major stenoses. Discrepancies between ultrasonography and angiography were due mainly to minor stenoses and large plaques of calcification on the vessel walls, which masked very segmental 70% stenoses in 2 cases. Angiography is limited by its own resolution, does not show uncalcified vessel walls and does not give cross-sectional data. It would therefore be inappropriate for showing small plaques, the full extent of ectasia or for defining the carotid bulb accurately. The advantages of colour methods were in investigating sinuous or deep vessels and hypoechoic plaques. Analysis of the residual lumen of a stenosis and its extent could be determined more rapidly. Haemodynamic quantification of stenoses by standard duplex sonography may be difficult because of limited sample volume and error in estimation of angle, whereas colour Doppler allows semiquantitative estimation of haemodynamics.(ABSTRACT TRUNCATED AT 250 WORDS)

A numerical model based on Navier-Stokes equations was used in conjunction with an experimental model in rabbits to study the effects of acute intracranial hypertension on basilar artery blood flow velocity. The hypertension was induced by pressure transmission via an epidural pressure sensor inserted into a parietal intracranial opening. A critical value of half of the diastolic arterial pressure for the intracranial cerebral pressure was determined by both numerical and experimental models. At this intracranial cerebral pressure level, the total input resistance and total input compliance, determined by the numerical model, exhibited an increase of 27% and 10%, respectively, and the tissular compliance a decrease of 25% from their physiologic baseline values. When the intracranial cerebral pressure reaches the level of the diastolic arterial pressure, a zero diastolic flow is observed into the cerebral vascular system. This study validates the theoretical model, which could be used in assessing intracranial cerebral pressure noninvasively in humans when O2 pressure can be stabilized.

Fifty-five patients with a permanent or intermittent subclavian steal syndrome demonstrated by continuous wave Doppler were included in a prospective study: 25 patients without vertebro-basilar symptoms, 8 symptomatic patients with defined vertebro-basilar symptoms and 22 with hemodynamic vertebro-basilar occurrences. The basilar artery velocity was recorded by Transcranial Doppler Sonography in baseline conditions, and after a hyperaemia test to the upper limb. A spontaneous, incomplete basilar steal was diagnosed in seven patients, and a complete basilar steal in one patient, (14.5% of the cases). After hyperaemia test, 18 other incomplete basilar steal were observed. The occurrence of a basilar steal was higher in the vertebro-basilar group (57% of the cases) especially in 7 of the 8 cases with defined vertebro-basilar symptoms; it was lower in the patients without vertebro-basilar occurrences (36% of the cases). This basilar steal was also seen in five of the six symptomatic patients with opposite vertebral artery stenosis above a 50% diameter. Transcranial Doppler Sonography could help to define a subgroup of subclavian steal syndrome with a high risk of strokes.

The purpose of this prospective study was to assess the value of continuous wave Doppler velocimetry, standard duplex scanning and color Doppler flow imaging in the diagnosis of carotid dissections. From 1975 to 1993, 42 patients (mean age, 44 +/- 14 years) were admitted to the University Hospital of Angers for a carotid dissection studied first by ultrasonography, then defined by angiography. Five cases were bilateral. Continuous wave Doppler examination revealed signs of severe obstruction of the carotid arteries in 96% of the cases (occlusion, extensive submandibular tight stenoses, significant slowdowns in the carotid and ophthalmic vessels, retrograde ophthalmic blood flow). Standard duplex scanning suggested dissection in 72% of the cases (tapering stenoses or occlusion, segmental ectasis, tubular vessel, peripheral residual channel, or rare irregular "membrane"). Color Doppler flow imaging suggested a dissection in 82% of the cases. This method has the advantage of underlining the peripheral channel, the double lumen, and the dissecting hematoma, which often is hypoechoic. The ultrasonic methods (continuous wave Doppler combined with color Doppler flow imaging) failed only when they are performed late and when moderate or segmental intrapetrosal dissections were present. These ultrasonic investigations would thus appear to be useful for early diagnosis of carotid dissections.

The purpose of this study was to compare transcranial Doppler sonography (TCD) and 99Tcm-HMPAO cerebral scintigraphy in detecting the effects of acute intracranial hypertension by pressure transmission using a previously validated model. In 20 New Zealand rabbits, cerebral blood flow velocities of basilar artery and carotid siphon were simultaneously monitored in baseline conditions and during acute intracranial hypertension by pressure transmission. This hypertension was induced by progressive steps of 5 mmHg, for a 5 min duration by elevating a saline infusion bottle connected to the subdural space. In baseline conditions, significant correlations were found between basilar artery resistive index and 99Tcm-HMPAO uptake in brain stem, r = 0.5 (p0.05) and posterior cerebral areas, r = 0.78 (p0.001). Severe intracranial hypertension equal to the diastolic arterial pressure with a cerebral perfusion pressure of 22.8 +/- 12.7 mmHg significantly decreased the basilar artery blood flow velocities and global 99Tcm-HMPAO cerebral uptake. At this level of intracranial pressure, few correlations between the two methods were observed. TCD detected relatively high blood-flow velocities in the carotid siphon appearing to result from proximal cerebral artery vasospasm. Transcranial pulsed Doppler provides data about haemodynamic changes such as hypoperfusion, vascular resistance increase in the basilar artery territory and vasospasm of the carotid siphon. 99Tcm-HMPAO scintigraphy, which has not yet been studied during intracranial hypertension, gave immediate information on local cerebral perfusion. Cerebral scintigraphy demonstrated a significant diffuse and heterogeneous decrease in cerebral blood flow, without dissociation between supratentorial and infratentorial territories, and tissue perfusion deficit owing to arterial vasospasm. TCD provides emergency investigation in patients with severe head injuries or hydrocephalus. 99Tcm-HMPAO complements TCD in cases of vasospasm and in determining an area of perfusion tissue deficit.

The aim of this prospective study was to investigate the additional information provided by transcranial pulsed Doppler for the determination of the upper part of dissections of the carotid and vertebral arteries and following-up. Earlier results concerning the role of ultrasound investigations for this indication have been presented elsewhere. Twenty-nine patients were examined (17 females, 12 males; mean age 43 years). All had arterial dissections confirmed by arteriography. There were 24 carotid dissections and 12 vertebral dissections. Investigations were performed during the acute phase and 2 months later. Most of the severe endocranial stenoses were identified by transcranial Doppler: 5 out of 6 severe stenoses of the carotid siphon and 6 out of 7 vertebral stenoses. The haemodynamic effect as measured by sylvian flow was significantly greater (p0.01) after a permanent ischaemic event than after temporary events and improved significantly with time (p0.008). There was no significant variation in the pulsatility transmission index (PTI), but this index requires a reference artery and is not particularly adapted in cases with bilateral dissection. Collateral perfusion, observed during the acute phase in all cases of occlusion and in 6 of the 8 carotid stenosis, was insufficient in half of the cases. Transcranial pulsed Doppler can be used to guide arteriography and helps determine the length of the dissection. It provides an easy way to assess the haemodynamic consequences of the dissection and is quite useful during follow-up.

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.

Resume Les fistules arterio-veineuses spontanees de l'artere vertebrale sont rares (41 cas decrits dans la litterature). Un souffle cervical continu est constamment retrouve a l'auscultation. Il est une decouverte d'examen systematique dans 30 p. 100 des cas; sinon, ces fistules se revelent par des acouphenes pulsatiles unilateraux (30 p. 100) ou par des accidents ischemiques transitoires vertebro-basilaires (20 p. 100). Les principales complications de ces fistules sont les accidents ischemiques dans le territoire vertebro-basilaire et l'insuffisance cardiaque essentiellement chez l'enfant. Elles se rencontrent dans 40 p. 100 des cas. L'âge de revelation de ces malformations apparait conditionner le pronostic: 6 complications cardiaques sur 7 se produisent avant 10 ans: seules 2 complications sont observees au-dela de 50 ans; en revanche, l'anciennete de ces fistules et leur complexite ne semblent pas intervenir. L'exploration doppler cervico-cephalique guidee par la clinique conforte le diagnostic, et renseigne sur un eventuel hemodetournement. L'arteriographie par voie arterielle, indispensable en pre-operatoire, constitue souvent un premier temps therapeutique (embolisation, voire dans 4 observations, obliteration spontanee de la fistule au cours de cette investigation). La surveillance des formes asymptomatiques, dont l'embolisation et la chirurgie ont ete differees, peut maintenant etre assuree par les ultrasons.

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.

The transcranial Doppler 2 MHz test, a new non-invasive investigatory method, allows direct instantaneous recording from middle cerebral artery in 96% of healthy subjects and, in contrast to classical means of measuring cerebral blood flow, the possibility of continuous monitoring of middle cerebral artery in bedridden patients or during operation. This transcranial pulsed Doppler (T.P.D.) test was used to study the effect of a calcium inhibitor, Nifedipine, on middle cerebral artery smooth muscle and its cerebrovascular effects in 28 subjects: 8 cases of hypertension, 9 of sylvian artery stenosis confirmed by arteriography (5 approximately equal to 30% and 4 greater than or equal to 50%) and 11 healthy volunteers. Recording of middle cerebral artery flow by T.P.D. was preceded by cervicocephalic continuous emission Doppler exploration (DMS, MIRA 4 MHz) and vascular echotomography (Duplex Sonedap 10 MHz). Recordings from the first segment of middle cerebral artery were obtained from a low frequency (2 MHz) and high power (maximum 350 mW) probe introduced facing squamous portion of temporal bone. Identification of this artery is dependent on its depth of access--average 5 cm--its response to homolateral carotid artery compression and the convergence of its flux towards the probe. After sublingual absorption of 2 to 3 capsules of Nifedipine, systolic and diastolic blood pressure and systolic and diastolic frequencies of middle cerebral activity were recorded regularly over 20 minutes with the patient at rest in dorsal decubitus. Variations in these parameters were considered significant when 10% or more. Criteria proposed for identification of middle cerebral artery stenosis were segmental acceleration of 3 kHz or more with or without associated turbulence (fig. 2).(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Among 59 cases of bismuth encephalopathy, 8 patients were observed to have osteo-articular lesions of the shoulders and dorsal vertebral. These included osteonecrosis of the head of the humerus, which has been reported previously, uni- or bi-lateral fractures of the upper end of the humerus, and vertebral fractures. Severe and repeated myoclonic spasms appear to be capable of causing fractures; microscopic fractures in the spongy bone could explain the osteonecrotic images observed.

Two cases of Morvan's chorea are reported. One of the patients presented the characteristic of having had two attacks, the first after organic mercury preparations, and the second after gold salts for inflammatory rheumatism. The second case had facial fibrillations only, and this was followed by a regressive polyradiculoneuritis one month later. This latter case raises certain diagnostic problems. The existence of a particular type of immuno-allergic tendency could be validly related to a triggering effect of various etiological agents (metals such as mercury or gold salts, or infective agents). The absence of hypotonia, and a regressive course appear to be the characteristics that distinguish fibrillary chorea from the continuous activity syndrome of the muscle fibers described by Isaacs.

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)

The authors report the case of a flavivirus encephalitis (probable Dengue) in a 70 year old female, occurring twenty days after a fewer of unknown origin, contracted in the South of India. Most of the cases of such encephalitis have been reported from children, but they may occur also in adults.

The urinary excretion of amino-acid have been determined by ionic exchange chromatography for 10 cases of bismuth encephalopathy and for 15 normal controls. The ninhydrine positive constituant reported by Burns in 5 cases of encephalopathy has not been detected. We are thinking it may be related to the use of a rich amino-acid solution during perfusions. We did not find any significant difference between the urinary excretion of amino-acid average value to the two groups. We found an increase excretion when severe encephalopathy were observed. Separate analysis of individual amino-acid excretion showed the following results: i) average percent of tyrosine excretion is lower in controls as in encephalopathies; ii) among the different ratios tested only SER + THR)/TYR and VAL/TYR are different in the two groups.

The authors report three clinical observations of drug resistance; two of them have their origin in French Guiana and the third one in East Africa. They note that these cases are linked to bad advice of prevention concerning the risk of malaria, diagnosis carried out sometimes late for these zones of resistance; they recommend: to inform and teach the patient how to use a self-treatment in case of bout of malaria, to give better advice to the Physicians concerning the reality of malaria in 1985 instead of using a complex diagram of chemoprophylaxis.

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.

Spontaneous arteriovenous fistulae of the vertebral artery are rare (only 41 cases in French and English-language literature). Auscultation regularly discloses a cervical bruit which was found by systematic examination in 30 p. 100 of the cases. Otherwise, the fistula was revealed by unilateral pulsatile tinnitus (30 p. 100) or by a transient vertebro-basilar ischaemic accident (20 p. 100). The main complications, which occurred in 40 p. 100 of the cases, were ischaemic accidents in the vertebro-basilar territory and, primarily in children, heart failure. Prognosis seems to be governed by the patient's age at the time of diagnosis: 6 out of 7 cardiac complications occurred before the age of 10, and only 2 beyond the age of 50; in contrast, the duration and complexity of the fistula do not appear to be prognostic factors. Doppler examination of the neck and head, based on clinical findings, confirms the diagnosis and provides information on a possible blood steal. Arteriography by the arterial route is mandatory before surgery, but it also represents a first therapeutic measure (embolization, or even spontaneous obliteration of the fistula during the procedure, as seen in 4 cases). Asymptomatic forms, for which embolization and surgery may be postponed, can be monitored by ultrasounds.