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J M de Bray

Publications and source records attributed to J M de Bray.

14 recordsLinked to original sources
PubMed1992

Acute intracranial hypertension and basilar artery blood flow velocity recorded by transcranial Doppler sonography: an experimental study in rabbits.

The relationship between intracranial hypertension and basilar artery blood flow is not well known, and it is not yet definite that the reduction of cerebral flow depends on cerebral perfusion pressure rather than microvessel compression. The purpose of the study described here was to investigate the effect of acute intracranial pressure on the basilar flow velocity, the cerebral perfusion pressure, and the systemic arterial pressure. The basilar Doppler signal was recorded continuously in 24 New Zealand rabbits by transcranial pulsed Doppler method. The acute intracranial hypertension was induced by the progressive raising, in steps of 5 mmHg, of a saline infusion bottle connected to an epidural sensor. The intracranial hypertension induced a decrease in diastolic and mean flow velocities in the basilar artery, and an increase in the resistance index. Cerebral perfusion pressure was significantly correlated with flow parameters. The basilar diastolic flow began to decrease significantly from a 35-40 mmHg intracranial pressure and for a 37 mmHg + 20 SD cerebral perfusion pressure, without significant variation of arterial pressure. Diastolic flow dropped to zero for a 53 mmHg intracranial pressure and a 30 mmHg + 15 SD cerebral perfusion pressure. These results show that high intracranial pressure values are necessary for significantly reducing basilar artery blood flow. This effect, and the increase of circulatory cerebral resistance, occurred before significant changes in systemic arterial pressure.

Animals↗
PubMed1990

[Carotid dissection. Study of 28 cases. Contribution of Doppler exploration, ultrasonic diagnosis and Doppler color echography].

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.

Adult↗
PubMed1989

[Long-term study of 20 cases of proximal stenosis of the middle cerebral artery. Role of transcranial Doppler ultrasound].

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.

Adult↗
PubMed1989

[Ultrasonic study of 22 cases of carotid artery dissection].

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)

Adult↗
PubMed1989

[Analysis using transcranial Doppler of hemodynamic consequences in 58 severe obstructions of the internal carotid artery. Preliminary results].

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.

Adult↗
PubMed1988

Transcranial Doppler evaluation of middle cerebral artery stenosis.

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.

Adult↗
PubMed1988

[Non-invasive methods for vascular studies in the diagnosis of deep venous thrombosis].

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.

Angiography↗
PubMed1986

[Spontaneous arteriovenous fistulas of the vertebral artery. Apropos of a case--review of the literature].

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.

Angiography↗
PubMed1985

[Drug resistance in malaria, what to do? Apropos of 3 cases].

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.

Adult↗
PubMed1985

[Vertebral osteonecrosis. Apropos of 3 cases, 1 complicated by spinal cord compression and 2 associated with another necrotic localization].

The authors report three cases of vertebral osteonecrosis which presented the phenomenon of intra-vertebral space. These patients had osteoporosis with vertebral compression. Two received steroid therapy. One case progressively developed spinal cord compression and the two other cases had an associated osteonecrosis (femoral head and talus). After reviewing the literature, the authors stress the relative frequency of neurological complications, in particular spinal cord compression (7 per cent).

Adrenal Cortex Hormones↗
PubMed1979

[Morvan's fibrillary chorea].

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.

Aged↗
PubMed1978

[Chromatography of urinary amino-acid in bismuth encephalopathy (author's transl)].

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.

Adult↗
PubMedDate not supplied

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.

Aged↗