A truncated ultrasound screening procedure for atheroma of the cervical arteries in asymptomatic diabetic patients: evidence from a retrospective study.

AIM: To 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.

MRI study of transient cerebral ischemia in the gerbil: interest of T2 mapping.

RATIONALE AND OBJECTIVES: The aim of this study was to evaluate the diagnostic use of MRI and, more precisely, the use of quantitative T2 imaging at 7 T for the early detection of neuronal cerebral alterations after transient ischemia in the gerbil. METHODS: One hundred forty-seven Mongolian gerbils were separated into four groups for which a bicarotid artery occlusion lasted for 4, 6, 8, or 10 minutes, respectively. The animals were scanned before carotid artery occlusion and at 3, 6, 10, 24, and 48 hours and 5 days after the ischemic incident. MR images were acquired on a Bruker Avance DRX300 mini-imaging system. RESULTS: Our results show that T2 mapping is able to localize brain damage induced by transient ischemia and to detect early perturbations in water content (as early as 6 hours after ischemia). CONCLUSIONS: T2 measurements in the striata are correlated with the severity of the ischemic incident, since the changes observed on the T2 images are directly proportional to the duration of occlusion.

Spinal cord compression related to vertebral osteonecrosis.

The authors report 3 cases of spinal cord compression by vertebral collapse related to osteonecrosis. Two patients needed surgical decompression permitting pathological diagnosis. In the third case, osteonecrosis was ascertained by radiological evidence of an intravertebral vacuum phenomenon. Three etiologic factors were noticed: osteoporosis, corticotherapy, and radiotherapy. The relative frequency of neurologic complications in vertebral collapse related to osteonecrosis compared to those observed in osteoporosis is discussed.

99Tcm-HMPAO cerebral scintigraphy and transcranial pulsed Doppler in acute intracranial hypertension in rabbits.

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 (p < 0.05) and posterior cerebral areas, r = 0.78 (p < 0.001). 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.

Transcranial Doppler sonography for blood flow velocity measurement during pharmacological tests.

Transcranial Doppler sonography, using a 2 MHz pulsed Doppler system, is suitable for non-invasive continuous monitoring of middle cerebral artery blood flow velocity during pharmacological studies. Methodological problems, and factors affecting cerebral blood flow have to be discussed (vasomotor spontaneous changes, intracranial blood pressure, blood viscosity, heart rate, vascular risk factors, etc.). Arguing from a previous study in 28 subjects (11 healthy volunteers, 8 hypertensive patients, 9 patients with middle cerebral artery stenosis), showing the hypotensive action of Nifedipine, without significant decrease of cerebral blood flow in 83% of cases, we emphasize the advantages and limits of this new non-invasive method for cerebral blood flow monitoring.

Social and economical effectiveness of non-invasive vascular examinations in the clinical management of thrombo-embolic disease.

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.

[Cerebral HITS: diagnosis, clinical relevance, outlook]. / Hits cérébraux: diagnostic, pertinence clinique, perspectives.

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.

[Transcranial Doppler study of sylvian vascular reactivity as affected by a calcium inhibitor. Preliminary results apropos of 28 cases]. / Etude par Doppler transcranien de la réactivité vasculaire sylvienne sous l'effet d'un inhibiteur calcique. Résultats préliminaires à propos de 28 observations.

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)

[Carotid dissection. Study of 28 cases. Contribution of Doppler exploration, ultrasonic diagnosis and Doppler color echography]. / Les dissections carotidiennes. Etude de 28 cas. Apports de l'exploration Doppler, de l'echotomographie et de l'écho-Doppler couleur.

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.

[Diagnostic contribution of ultrasonic diagnosis coupled with pulsed Doppler combined with continuous Doppler to the exploration of the vertebral arteries of atherosclerotic patients. Preliminary report]. / Contribution diagnostique de l'échographie couplée au Doppler pulsé, en association au Doppler continu, pour l'exploration des arteres vertébrales de sujets athéroscléreux. Rapport préliminaire.

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)

[Transcranial Doppler ultrasonic examination in vertebro-basilar circulatory pathology]. / Le Doppler transcrânien en pathologie circulatoire vertébro-basilaire.

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.

Ultrasound characterization and quantification of carotid atherosclerosis lesions.

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.

[Non-invasive methods for vascular studies in the diagnosis of deep venous thrombosis]. / Les méthodes non vulnérantes d'exploration vasculaire pour le diagnostic de la thrombose veineuse profonde.

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.

[Doppler transcranial ultrasonography in carotid and vertebral dissections: 36 cases involving angiography]. / Le Doppler transcranien dans les dissections carotidiennes et vertébrales: étude de 36 cas artériographies.

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 (p < 0.01) after a permanent ischaemic event than after temporary events and improved significantly with time (p < 0.008). 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.

[Pulsed transcranial Doppler examination in the acute phase of stroke]. / Le Doppler pulsé transcrânien à la phase aiguë de l'infarctus cérébral.

INTRODUCTION: 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. STATE OF ART: This non-invasive low-cost investigation can be undertaken rapidly, within 10 minutes if guided by focal symptomatology. It detects middle cerebral artery stenosis in >or=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. CONCLUSION: 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.

[Ultrasonic study of 22 cases of carotid artery dissection]. / Etude ultrasonique de 22 dissections carotidiennes.

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)

[Long-term study of 20 cases of proximal stenosis of the middle cerebral artery. Role of transcranial Doppler ultrasound]. / Etude à long terme de 20 sténoses proximales de l'artère cérébrale moyenne. Rôle du Doppler transcrânien.

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.

[Trismus, pseudobulbar syndrome and cerebral deep venous thrombosis]. / Trismus, syndrome pseudobulbaire et thrombose veineuse profonde cérébrale.

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.

[Morvan's fibrillary chorea]. / Chorée fibrillaire de Morvan.

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.

[Cervical deficit radiculopathy in 3 cases of vertebral artery dissection]. / Radiculopathie cervicale déficitaire au cours de trois cas de dissection de l'artère vertébrale.

Three cases of extracranial vertebral artery dissections with upper limb peripheral motor deficit (C5-C6) are reported. Six similar cases were also found in the literature. Central neurological symptoms occurred in five of these nine cases, suggesting the diagnosis of dissection. The peripheral motor or sensorial deficit was strictly isolated in the four other cases, simulating radicular neuralgia due to discopathy or foraminal compression. In case of dissections, a precise analysis of pain is helpful to guide diagnosis; sharp, unbearable, continuous and extended neck pain without nocturnal paroxysms and posterior neck stiffness is typical. Analgesics or anti-inflammatory drugs are ineffective. Peripheral motor deficit is more common than sensory deficit. Recovery was complete in this series. In most cases, the radiculopathy appears to be due to cervical root compression in its extraforaminal course due to the dissection hematoma and rarely to radicular ischemia.