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One of the main goals of haemovigilance is to gather and analyze adverse events in recipients of blood products in order to improve blood safety. The French National Blood Service has a specific role in the management of immediate adverse events: to alert to quarantine the potentially dangerous blood products from the same donation(s), to provide blood testing for the etiologic assessment and to give transfusion advice to patients. The updating of the recipient's computer file allows a better monitoring for both immediate and delayed adverse events. Finally, the French National Blood Service's correspondent of haemovigilance is responsible for donor's inquiries, especially in cases of transfusion related to bacterial contamination, severe allergy, suspicion of transfusion acute related lung injury and viral seroconversion. The management effectiveness for adverse events requires a strong collaboration between all members of the haemovigilance network.

Resume Les ultrasons sont de plus en plus utilises en medecine pour l’examen des organes par echographie doppler. Les frequences les plus utilisees vont de 2 a 20 MHz. Le faible prix de revient et l’innocuite des ultrasons a vocation diagnostique expliquent leur large utilisation. Aujourd’hui, les ultrasons sont egalement utilises pour detruire des tumeurs et peut-etre demain pour delivrer localement des medicaments. Plusieurs equipes francaises, liees aux universites ou CHRU, au CNRS ou a l’Inserm ont mene des travaux determinants dans l’avancement des connaissances et le developpement de nouvelles methodologies cliniques. Plusieurs entreprises ou activites industrielles ont pu etre creees a partir de ces travaux. On trouvera ci-apres quelques points de repere sur ce qui fait le succes de l’imagerie ultrasonore et les techniques associees, en observant bien que le potentiel de creativite autour de l’echographie medicale s’est sans cesse renouvele.

Cerebral hypoxia-ischemia (HI) is an important cause of perinatal brain damage in the term newborn. The areas most affected are the parasagittal regions of the cerebral cortex and, in severe situations, the basal ganglia. The aim of this study was to show that the newborn piglet model can be used to produce neuropathology resulting from moderate HI insult and to monitor damage for 7 days. Two acute cerebral HI were induced in newborn Large White piglets by reducing the inspired oxygen fraction to 4% and occluding the carotid arteries. Newborn piglets were resuscitated, extubated and monitored for 7 days. (31)P magnetic resonance spectroscopy (MRS) offers the ability to monitor the severity of the HI insults. Lactate (Lac) was detected in the HI group at 2 h, 3 days and 5 days after insult by (1)H MRS. Lac/n-acetylaspartate and Lac/choline and Lac/creatine ratios increased significantly (p0.01) in the HI group 2 h after HI insults and remained high over 7 days. For the HI group, mean T(2) values increased significantly in the parietal white matter (subcortical) for 5 days after HI insult [117.5 (+/-7.4) to 158.5 (+/-19.2) at T+3 days, 167.7 (+/-15.4) at T+5 days and 160.9 (+/-10.1) at T+7 days (p0.01)]. This newborn piglet model of moderate HI brain injury with reproducible cerebral damage could be use as reference for the study of neuroprotective strategy for a period of 7 days.

Fetal heart rate (FHR) monitoring is widely used to evaluate fetal health and is based on the detection of movements of the fetal heart by Doppler ultrasound. Fetal health can also be evaluated by prolonged observation of body- and pseudo-respiratory movements using two-dimensional ultrasound. Fetal breathing movements are in particular considered to be an important indicator of fetal well being. Ultrasonic Doppler signals caused by movements of the fetal heart were analyzed in detail. The signals were acquired from five healthy fetuses. Minor changes in the insonification geometry gave rise to great variations in the aspects of successive heartbeats. The signals are shown to contain information on both maternal and fetal respiratory movements. This may facilitate the development of a simple method for fetal respiration monitoring coupled to standard FHR monitoring.

Mineralogical, chemical and O-isotopic analyses were performed on the clay matrices surrounding two natural fission reactors of the Oklo deposit. In the deeply preserved reactor 10 (450 m), clays are composed of hydrothermal Mg-chlorites and sudoites (Al-chlorites). The wide range of their O-isotopic compositions (from 0.0 to 15.1‰ SMOW) is consistent with crystallisation during conditions of criticality, when the reactors created a thermal gradient of 100°C/m. The temperature in the core of reactor is calculated to have been approximately 400°C. In contrast, in the shallow reactor 9 (120 m deep), vermiculitized Al-chlorites are the products of the weathering of the hydrothermal chlorites. These vermiculitized Al-chlorites are 18 O enriched ( δ 18 O =18‰ SMOW) and underwent interaction with surface fluids (−2 to −5‰). 149 Sm / 147 Sm isotopic ratios of the clays of reactor 9 show a wide dispersion (2–3 m) of the fissiogenic Sm around the reactor. The migration of the fissiogenic Sm, which is usually retained in the deep reactors, is here related to the circulation of meteoric water under oxidising conditions.

The aim of this study was to determine the influence of neonatal focal cerebral hypoxia-ischemia (HI) on sleep-waking pattern, electrocorticogram (ECoG) power spectra and locomotor activity (LA) in adult Wistar rats. Seven-day old pups were subjected to permanent unilateral ligation of the common carotid artery and transient hypoxia (8% O2). At 10 weeks of age, the extent of brain damages was evaluated by magnetic resonance imaging (MRI) and homogenous injured animals were selected before chronic implantation of radiotelemetry device. Using a single ECoG recording channel method, waking (W), paradoxical sleep (PS) and slow wave sleep (SWS) were continuously recorded for 72 h and they were semi-automatically analyzed off-line. We observed that neonatal HI triggers a cascade of events leading, in adult rats, to brain dysfunction characterized by an increase in SWS (55.0 vs. 40.2% in sham-operated rats, p

Objectives: Clinicians are more and more frequently studying fetal blood flow velocity curves recorded by Doppler ultrasound in vital organs such as the placenta and fetal brain to evaluate fetal well-being. We have therefore developed a mathematical model of the utero-placental and fetal circulations which could be used for teaching and for a better understanding of regulatory mechanisms. Methods: The model is based on two basic elements—an arterial segment and a bifurcation—and we have reproduced the major arteries of the feto-maternal circulation combining these basic elements. The mathematical model of the system is based on the Navier–Stokes equations. The peripheral areas such as the brain, kidneys and placenta are modeled by a simple Windkessel model and the model computes instantaneous flow and pressure at any point in the fetal arterial tree and the uterine arteries. Results: We have compared the computed instantaneous flow curves and pressure with in vivo data and our results agree with the findings in physiological situations and in gravidic hypertension. Conclusions: Our model provides new interesting insights into fetal hemodynamics such as a better understanding of the mismatch impedance phenomena and is a promising model for the study of blood redistribution mechanisms in hypoxic situations.

The phonophoresis of digoxin was studied in vitro through human and hairless mouse skin. Sonication was carried out with continuous mode at an intensity of 1 and 3 W/cm2 and a frequency of 3.3 MHz for 10 min. Sonication at 3W/cm2 significantly increased the absorption of digoxin through mouse skin. Percutaneous penetration was not increased using an intensity of 1W/cm2 under the same experimental conditions. Enhanced digoxin penetration at 3W/cm2 can be explained by the mechanical and/or thermal action of ultrasound waves. Thermal simulation from electrical resistance increased digoxin flux in comparable amounts to those obtained by sonication at 3 W/cm2. There was no enhancement of digoxin absorption across human skin by ultrasound, probably due to dermal retention of this lipophilic drug. Further studies will be necessary to determine the relative importance of the thermal effects of ultrasound on percutaneous administration of drugs.

Resume Le metabolisme cerebral a ete abondamment etudie ces dernieres annees par spectroscopie par resonance magnetique (SRM). L'application en neonatalogie permet de suivre la maturation cerebrale ainsi que l'installation et l'evolution de la souffrance cerebrale. L'utilisation de la spectroscopie phosphore permet de quantifier les metabolites phosphoryles ; ainsi, la mesure des concentrations relatives en phosphocreatine et en phosphate inorganique constitue un element pronostique fiable quant au devenir d'un nouveau-ne ayant subi un accident hypoxoischemique. L'etude des concentrations absolues a fait l'objet de travaux recents et semble encore plus performante. La spectroscopie du proton visualise des metabolites tels que la choline, le N-acetylaspartate, le lactate ou la taurine. Son utilisation est plus recente que celle du phosphore mais les resultats montrent deja son interet en neonatalogie.

Resume Cette revue sur les potentiels evoques (PE) cognitifs chez l'enfant comporte deux volets. Le premier concerne l'apport des PE cognitifs dans les etudes du developpement normal. Les PE cognitifs varient en effet d'une part en fonction de l'âge de l'enfant et d'autre part en fonction des processus cognitifs mis en jeu lors des tâches realisees. Les etudes topographiques permettent egalement de preciser les regions du cerveau impliquees dans ces processus cognitifs specifiques. Le deuxieme volet correspond a deux exemples de pathologie developpementale (trouble de l'attention et autisme) ou les PE cognitifs permettent de mieux comprendre les dysfonctionnements qui sous-tendent les desordres cognitifs observes.

Objective: Although echotomography is a valuable method to diagnose certain acute bowel diseases, the non-specificity of the observed wall thickening is a limitation for a clear positive diagnosis in routine practice. Our hypothesis was that a wall thickening was accompanied by an increased blood flow in acute inflammatory and tumoral processes. Materials and methods: Color coded Doppler (CCD) has been used in emergency in 25 adults to objective possible changes in gastrointestinal blood flow. The final diagnosis was based on clinical records or results of surgery. Results: In the 10 control subjects, vessels were not detected in gallbladder or gastrointestinal walls. In the 25 patients (acute cholecystis, colon cancer, appendicitis, gastric lymphoma, Crohn's disease), CCD easily detected small arteries located at the periphery or within the thickened wall (one vessel in seven cases). In Crohn's disease, the presence of detected vessels would be an argument for establishing an increase in the inflammatory process. Conclusion: The presence of arterial blood flow in a thickened gastrointestinal wall is valuable for assessing a positive diagnosis of acute inflammatory or tumoral lesions.

Using the noninvasive transcranial ultrasonic Doppler method, flow dynamics of the middle cerebral arteries were investigated in relation to auditory stimulations in 12 children with autistic behavior compared with 12 normal controls and 10 mentally retarded children. In normal children, auditory stimulation evoked lateralized modifications: blood flow increased and resistance index decreased on the left side; such modifications were not recorded on the right side. This pattern should indicate vasodilation mechanisms induced by changes in the metabolism of the brain areas supplied by the left middle cerebral arteries (MCA). Although less asymmetrical, this pattern was also found in the mentally retarded children. Autistic children significantly differed from these two groups. They displayed a symmetric pattern of responses with a blood flow decrease and resistance-index increase on both sides; this could suggest abnormal metabolic mechanisms induced by auditory stimulation in autistic children and could be related to the previous hypothesis of impairment in the development of cerebral lateralization in autism. These preliminary results show that transcranial Doppler ultrasonography may be a valuable and practicable tool for the noninvasive study of evoked blood flow responses in psychopathology.

High spatial resolution is required for echographic exploration of the skin, microvessels or small laboratory animals. With the scanner described here, high resolution is obtained by means of a strongly focused, wide-band 17 MHz center frequency transducer (−6 dB bandwidth: 22 MHz). The movement of this transducer above the skin provides a 6 mm wide and 5 mm deep echographic cross-section with an image rate of 15 images/s. The resolution is about 0.08 mm in axial and 0.2 to 0.3 mm in lateral directions. The device was tested on phantoms in water and in vivo on normal and pathological skin in the Department of Dermatology. With the easy-to-handle probe, explorations were made on psoriasis, basocellular carcinoma, malignant melanoma and sarcoidosis.

Radioiodinated m-iodobenzylguanidine [( 125I]MIBG) and tritiated norepinephrine [( 3H]NE]) uptake and release were compared, in different regions of the brain of the rat. The classification of the regions according to uptake was the same for both tracers:striatum greater than hypothalamus greater than hippocampus greater than cortex greater than brainstem. Tetrabenazine (TBZ), a granular monoamine uptake inhibitor reduced the uptake in the different regions. The inhibition rate was higher for [3H]NE uptake than for [125I]MIBG. The spontaneous release was the same for [125I]MIBG and [3H]NE and was the lowest in the striatum. The K+ stimulated release of [3H]NE was more complete than the release of [125I]MIBG and was the most important in the striatum. From these results, it is inferred that MIBG enters the brain tissue via NE uptake mechanisms. It appears that MIBG is stored in the chromaffin granules, as NE, but also in the cytoplasm. A modified molecule derived from MIBG which would cross the blood-brain barrier, would then appear as a potential scintigraphic marker of monoamine uptake, storage and release.

Objectifs Quantifier l’augmentation de zone detruite par HIFU lors de l’infusion de microbulles. Materiels et methodes Le traitement par HIFU (3MHz, 1500 W/m 2 ) a concerne le tiers superieur des reins droit et gauche de 10 lapins (2,5 kg) par un prototype a guidage echographique (Theraclion ® , Paris). Le traitement (50 tirs sur 14 minutes, zone theorique de 430 mm 3 ) a ete effectue sans ou avec infusion de SonoVue ® (0,3 ml/mn). Une mesure des volumes detruits etait faite par echographie et macroscopie lors de l’autopsie a 72h. Resultats Ont ete retenus 6 traitements sans et 6 traitements avec microbulles. Aucune brulure cutanee n’a ete observee. Le volume necrose etait fortement augmente avec microbulles (52 [14-152] versus 5 [0-18] mm 3 , p = 0,0065). Sans microbulles 4 reins ne presentaient pas de lesions visibles mais tous les reins traites avec microbulles presentaient une lesion detectable. Conclusion Le fort accroissement de la zone traitee par ultrasons en presence de microbulles permettrait de proposer une modulation de duree ou intensite pour un plus grand confort des patients.

Objectifs Quantifier la zone detruite en HIFU par echographie de contraste des la fin de la session therapeutique. Materiels et methodes Le traitement par HIFU (3MHz, 1500 W/ m2, 50 tirs sur 14 minutes, zone theorique de 430 mm3) a concerne le tiers superieur renal de 10 lapins (2,5 kg) par un prototype a guidage echographique (Theraclion®, Paris). Une mesure des volumes detruits etait effectuee par echographie conventionnelle lors de l’autopsie a 72h. A la fin de la session etait realisee une echographie de contraste (CnTI, Esaote) apres bolus intraveineux de 0,3 ml de SonoVue®. Resultats Douze traitements ont ete pris en compte. Le volume necrose moyen mesure a 72h etait de 44 ± 47 mm3. Dans aucun cas il n’a ete possible de mettre en evidence une zone ischemique a l’echographie conventionnelle et de contraste a la fin de la session alors que, a 72h, ces volumes etaient clairement mesurables. Conclusion L’echographie de contraste n’apparait pas adaptee pour evaluer precocement l’effet therapeutique des ultrasons amenant a rechercher d’autres modalites ultrasonores ou non.

Objectifs L’objectif etait de developper des techniques de traitement des signaux Doppler fœtaux dans le but d’evaluer le comportement du fœtus pendant la grossesse a partir de l’analyse du Rythme Cardiaque Fœtal, les mouvements pseudo-respiratoires et des mouvements globaux du fœtus. Le but final est de mettre au point un systeme de monitoring ambulatoire du comportement fœtal. Materiels et methodes Le materiel developpe est un systeme multicapteur a effet Doppler puise (Systeme ACTIFŒTUS) qui detecte les signaux Doppler fœtaux a 5 profondeurs successives dans l’uterus. La detection et la caracterisation de l’activite fœtale sont realisees grâce a un traitement de signal adapte suivi de l’extraction de parametres specifiques. Resultats Les enregistrements effectues sur 15 patientes ont permis de montrer la qualite des signaux de l’activite fœtale obtenus avec le systeme ACTIFŒTUS, et de valider la FFT et l’autocorrelation pour detecter l’activite cardiaque et les mouvements du fœtus. Nous avons pu egalement montrer que l’ACI permet de separer un melange de signaux Doppler. Plusieurs exemples de resultats seront presentes. Conclusion Les resultats obtenus permettent d’envisager le developpement d’une methode d’etude ultrasonore du comportement fœtal dans les conditions physiologiques, et de suivi de fœtus en situation de souffrance chronique.

A study of a method for exploration of microvessels is presented. Theoretical considerations taking into account the backscattering of ultrasound wave from a red cell and the attenuation versus frequency (up to 180 MHz) show that a frequency in the range of 80 to 120 MHz is most favorable for small depths of exploration (300 microns). The characteristics of the 113 MHz Doppler system which was built are described. The minimum detectable signal is 3 microV, the lateral resolution around 20 microns and the minimum length of the Doppler sample volume about 80 microns. The Doppler data are displayed in the form of a frequency spectrum. The first encouraging tests carried out using 20 microns rectangular glass capillary tubes and 50 to 150 microns microvessels of the mesentery of rat have demonstrated the resolution and the sensitivity of the system. A discussion illustrates the difficult problem of motion artefacts and the improvements which have to be made. From a technical point of view the authors think that it is possible to work with such a high frequency but there are two main difficulties: the processing of a very low frequency Doppler spectrum and the optimization of the probe (dimensions and shape).

Main results of cardiovascular investigation, performed with ultrasound methods during the common French/Soviet flight aboard Salyut VII in June 1982, are compared to variations of the same parameters studied during ground-based simulations on the same subject or observed by other investigators during various ground-based experiences. The antiorthostatic bed rest simulation partly reproduces microgravity conditions and seems to be better adaptated to cardiac hemodynamics, despite some differences, and to the cerebral circulation, than to the inferior limb circulation.

In 242 neurologically symptomless patients with at least one non-occlusive carotid stenosis on ultrasonography (continuous wave doppler and echotomography-B mode imaging) 171 carotids showed 0-50% stenosis, 150 showed 50-75% stenosis, and 78 showed more than 75% stenosis. The mean follow-up was 29.4 months, with stroke and death as end points. Of the 56 deaths 2 were causally linked to a stroke (crude annual mortality index 9.57%). Of the 10 strokes 7 were judged to be infarctions in carotid territory. 7 out of 20 patients with transient ischaemic attacks (TIA) had ischaemic symptoms definitely related to carotid territory. The crude annual indices of specific stroke or TIA were 0.45% for nonstenotic carotid, 0.23% for 0-50% stenosis, 2.48% for 50-75% stenosis, and 1.71% for 75-99% stenosis. Stenoses of greater than 50% were associated with more ischaemic events than were lesser degrees of narrowing (p less than 0.01).