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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.

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.

Purpose We assessed the resistance index (RI) in the superior mesenteric artery under fasting and postprandial conditions in healthy subjects and in patients with cirrhosis to determine whether the amount of change in the RI reflects the presence or severity of liver dysfunction. Methods Fifteen subjects with normal livers and 27 patients with cirrhosis underwent Doppler sonography of the superior mesenteric artery before and after ingesting a standard meal. The RI at baseline (fasting state) and the postprandial RI were compared between the 2 groups. The fasting RIs and post postprandial RIs changes in cirrhotic patients were correlated with the severity of disease. Results No difference was found between the baseline RIs in healthy (RI = 0.85) and cirrhotic subjects (RI = 0.84), nor was there a difference in baseline RIs between subgroups of cirrhotic patients according to the severity of liver disease. The RI decreased significantly (p < 0.05) after the meal in both the healthy (13%) and cirrhotic (8%) subjects, but the postprandial decrease was significantly less pronounced (p < 0.05) in cirrhotic patients than in healthy subjects. Among cirrhotic patients, there was no correlation between the postprandial decrease of the RI and severity of liver disease. Conclusions The marked decrease in the postprandial RI in the SMA in healthy subjects is generally not seen in patients with cirrhosis, and changes in the postprandial RI do not reliably predict the severity of liver dysfunction. © 1998 John Wiley & Sons, Inc. J Clin Ultrasound 26:131–136, 1998.

The value of sonography in lung diseases such as sarcoidosis is not established. Twelve patients with pulmonary sarcoidosis and eight control subjects underwent a sonographic examination using a high frequency probe (7.5 MHz). The normal lung surface showed smooth and regular hyperechoic patterns, respiratory motions, and occasionally minute interruptions with comet tails. All patients with sarcoidosis showed various surface abnormalities, which appeared irregular and rough with coarse interruptions, producing an increase of artifacts. Nodular patterns were found in nine of 12 patients (75%). Sonography also revealed abnormalities not diagnosed by chest radiographs (n = 2). These findings could offer an complementary approach for evaluating sarcoidosis.

For many years Doppler ultrasound has helped to identify the cause of renal allograft dysfunction. However, Doppler examinations were often performed after the onset of acute renal failure. In the present study we used Doppler ultrasound during grafting to follow changes in renovascular resistance. As early as 30 min after the renal artery had been unclamped, the calculated resistance index (RI) at the hilar part of the renal artery was significantly higher in the group of patients who developed acute tubular necrosis (ATN) than in the group of patients with early normalization of renal function (P = 0.05). This result did not correlate with raised cold and warm ischemia times and serum creatinine level on discharge in patients who presented with ATN. RI higher than 0.730 min after unclamping allows for an identification of those grafts at greater risk for the development of ATN and should be an indication for the early introduction of intensive therapy.

Thirty-nine consecutive patients with consolidated lung confirmed radiologically underwent sonography, and their sonograms were compared with results for 100 healthy subjects. The hyperechoic line of normal aerated lung and its air artifacts showed respiratory motions ("gliding sign," n = 100). Patients with pneumonia demonstrated distinct sonographic patterns. Strong linear echoes with characteristic air artifacts (air bronchogram) and anechoic tubular structures (fluid bronchogram) were visualized in 36 of 39 patients (92.30%). The superficial lung showed a homogeneous hypoechoic band termed "superficial fluid alveolograms" (n = 39) with respiratory motions in 35 of 39 patients. We conclude that sonography can evaluate pulmonary consolidation and may provide additional roentgenographic information, especially when fluid bronchograms are visualized.

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.

To enable the investigation of fetal movement in a manner similar to fetal heart rate (FHR) monitoring we have developed an apparatus (the DopFet system) that consists of a pair of miniature sensors, a 2-MHz continuous-wave directional Doppler electronic module and a laptop personal computer. One of the sensors is aimed at the fetal limbs and the other at the thorax to detect heart and upper body movements. The signals are analyzed, presented in real-time and postprocessed by software developed by us. The postprocessing software computes a number of parameters (the DopFet parameters) describing fetal movement. These parameters can be divided into two categories: parameters that describe the quantity of fetal movement (i.e., number of movements) and parameters that describe qualitative aspects of fetal movement (i.e., average movement duration). Future studies using the DopFet system will be aimed at discovering which of these parameters or combination of parameters is the best indicator of fetal well-being. We present an example of a 0.5 h recording and the results of testing on 23 volunteer mothers. These results show good sensitivity of the system compared to real-time ultrasound (US). The system detects 96% of rolling movements, 100% of flexion movements and 97% of leg movements.

In vivo ultrasonic characterization of the skin was performed at 40 MHz by estimating the slope of the attenuation coefficient in the human dermis. The centroid algorithm was first tested on simulated backscattered RF lines with a second-order autoregressive model to carry out the spectral analysis. A relative error of less than 8.5% and a relative precision of less than 6% were predicted for a 2-mm tissue thickness and for temporal window sizes ranging from 0.25 to 0.45 micros. In vivo measurements performed on 138 healthy volunteers yielded values of the attenuation coefficient slope ranging from 0.8 to 3.6 dB/cm MHz. A decrease was observed with advancing age, but no significant difference appeared between men and women. The results from this study suggest that this acoustic parameter shows the effect of the ageing process on normal skin tissue in vivo.

Various parameters are currently used for the semi-quantitative assessment of dopamine D 2 receptors and differ according to the delineation of the striatal region of interest (ROI) and the choice of the reference ROI. The aim of this study was to assess the value of different ROI approaches in differentiating patients with normal or increased numbers of D 2 dopamine receptors (group 1 = Parkinson's disease, n = 8) from patients with decreased dopamine D2 receptors (group 2 = other extrapyramidal syndromes, n = 9) using 123 I-iodolisuride SPET (ILIS-SPET). 123 I-iodolisuride (190 ± 31 MBq) and 99 Tc m -ethyl cysteinate dimer ( 99 Tc m -ECD) perfusion SPET were performed in the the same position, with a dual-headed gamera camera equipped with fan beam collimators. Both a geometric approach (ellipse, circle or rectangle) and an anatomical approach using the CT scan and perfusion SPET as anatomical guides were used to draw striatal and reference ROIs. A total of 33 different parameters were calculated for each patient, indicating the ratio of counts between the striatal and reference ROIs (frontal, occipital cortex or cerebellum) and the asymmetry between the right and left striatum. More significant differences between group 1 and group 2 were found by using geometric ROIs than by using anatomical ROIs. The most discriminant ratios were the caudate/occipital, caudate/frontal and striatum/occipital ratios (P = 0.001, P = 0.002, P = 0.003 respectively). A close correlation was found between the striatum/caudate and striatum/occipital ratios, but not between the striatum/frontal and striatum/occipital ratios or between the striatum/frontal and striatum/caudate ratios. We conclude that the occipital cortex is the best reference for the semi-quantitative evaluation of dopamine D 2 receptors as the frontal cortex could include some dopamine D 2 receptor-bound radioligand, and that the caudate/occipital ratio is an appropriate parameter for differentiating Parkinson's disease from non-Parkinson extrapyramidal syndrome by 1-iodolisuride SPET.

Foetal Heart Rate (FHR) monitoring using the Doppler shift resulting from the movements of the foetal heart is a standard examination in most obstetrical wards. Other movements also give rise to a low frequency Doppler shift. These signals are incompletely understood. Their characteristics may offer a way for diagnostic exploitation through complementing or replacing time consuming ultrasound observation of foetal movements. It is shown that a wealth of information is contained in these signals which can easily be extracted on line by a standard PC computer using straightforward methods of signal processing. In its amplitude an ultrasonic Doppler signal contains information concerning the size of the reflector in movement and speed as frequency. The displacement of the reflector can also be derived from the phase evolution of a complex Doppler signal. Examples of signals generated by various types of foetal activity are shown and analyzed.

Most techniques used so far for the evaluation of diaphragm kinetics are either invasive (electromyography, fluoroscopy), or indirect (respiratory pressures, impedance plethysmography). The aim of this study was to determine whether assessment with ultrasound or fluoroscopy differed, and which technique appeared more suitable in the investigation of quantitative hemidiaphragmatic displacement. Six patients (3 female, 3 male, aged 29 to 40) without respiratory disease were studied during systematic X-Ray chest examination, spirometry, and abdominal sonography. The amplitude of the right diaphragm motion could be measured in all patients with M-mode sonography as well as with fluoroscopy. The vertical ascending motion of the diaphragm measured by M-mode sonography, reached 60% of its maximum amplitude at 50% of inspiratory capacity. There was a significant correlation between the maximum amplitude of diaphragm motion as measured by M-mode sonography (5.8 +/- 0.4 cm; r = 0.89; p = 0.019) or fluoroscopy (5.6 +/- 0.7 cm; r = 0.84; p = 0.036) and the inspiratory capacity (2.73 +/- 0.39 l). M-mode sonography has technical, quantitative and qualitative advantages over fluoroscopy and should be the method of choice in the investigation of suspected diaphragmatic movement disorder. When coupled with other techniques like spirometry, this technique could represent a useful adjunct to functional respiratory studies.

Local lesions occurring after conservative surgery for breast neoplasms require diagnostic means capable of detecting and assessing the recurrence of such cancers. In the present color-coded Doppler was used in 20 women who had under gone conservative surgery (mean 4 years before) to screen all suspect lesions. Among the 14 malignant lesions assessed histologically, one or more arterial vessels were detected inside or beside the lesion in 13. Among the 6 benign lesions, only of one arterial vessel was detected, in all cases far from the lesion (12.5 to 3.3 mm). No significant difference was observed for systolic velocities and resistance index. These results indicate high accuracy of color coded Doppler examination associated with echotomography and mammography for positive diagnosis of recurrent lesions in post-conservative follow-up of breast cancer.

The length of the umbilical cord varies widely from one pregnancy to another. Although its average length is 50 cm, this measurement could vary from as little as 20 cm to more than one metre. The purpose of our study was to evaluate, in utero, the length of the umbilical cord during the third trimester of pregnancy knowing the propagation velocity of the pressure wave along the cord.The computation of the apparent length requires two ultrasound transducers, one situated at the aortic fetal arch, the other at the placental extremity of the umbilical artery. Knowing the velocity of the pressure wave (v), as well as the time interval between the systolic peak of two waves (delta t), we can deduce the length of the umbilical cord (delta t x v).The comparison between the calculated length and the actual length measured shows a significant correlation with a probability of 1%.The knowledge of the length of the umbilical cord is quite useful in the physio-pathological interpretation of the placental resistance index. It is also of interest, before the delivery, to know the length of the cord in order to foresee dystocy and how it relates cord which is either too short or too long.

Background. The aim of our study was to image psoriasis plaques by ultrasound to assess the changes in psoriasis and to measure and quantify them objectively. Materials and Methods. Thirty-one psoriasis plaques were studied in 19 patients. Measurements of skin thickness were obtained with a high resolution B-mode echographic system. Results. Some changes were seen in psoriatic skin. A new structural element was observed: a wide subepidermal nonechogenic band. The other changes were a decrease in dermal echoes that were less intense and less dense, and an increase in the epidermal and dermal skin thicknesses. The skin thickness was increased in all psoriasis plaques as compared to apparently normal skin (P < 0.001). The average increase was 67% for whole skin and 200% for epidermis. Conclusions. Ultrasound imaging of psoriatic skin allowed the identification of different skin changes induced by psoriasis, and particularly, the differentiation between epidermal and dermal alterations. We presume that epidermal thickness reflects epidermal proliferation and desquamation, and the increase in the dermal and whole skin thickness reflects infiltration. We feel that ultrasound imaging of psoriatic skin is a quantitative method that is as easy and noninvasive as the psoriasis area and severity index (PASI). It could be used for following up patients with psoriasis and could achieve widespread use, especially in research protocols.

It is proposed to use information on the direction of reflector movement and extensive filtering in the detection of fetal breathing and cardiac movements in the ultrasonic Doppler signal recorded on the surface of the material abdomen. The method appears fairly insensitive to spurious signals and allows those of interest to be distinguished without any reference technique. A decision rule for breathing and cardiac rhythm detection, incorporating movement direction, amplitude, shape and periodicity criteria, is also proposed.

Brain activation procedures associated with single photon emission computed tomography (SPECT) recently have been developed in healthy controls and in diseased patients to help in their diagnosis and treatment. We investigated the effects of an electrical stimulation of the auditory nerve on the cerebral distribution of 99mTc-HMPAO in seven profoundly deaf adults. The promontory test was positive (PT+) in six patients and negative (PT-) in one. A count increment of the temporal cortex was observed in all patients, and was higher in all patients with PT+ (right 20%, left 19%) than in the patient with PT- (right 9%, left 3%). These results led us to consider 99mTc-HMPAO brain SPECT imaging as a potential preoperative test for cochlear implant. It might be helpful for the evaluation of cortical perfusion response to an electrical stimulation. Sensitivity tests for the method are requested before this clinical application.

A computer model was used to study the primary factors generating the reduction in resistance index, (S-D)/S, values observed by ultrasonic Doppler measurements in the umbilical artery, from the fetal insertion to the placental insertion (S represents the amplitude of the systolic peak and D the amplitude of the diastolic peak). This hemodynamic approach shows that the placental resistance is the primary factor, the viscosity and the cord length playing secondary roles. Clinically, the position of the measurement along the cord is an important factor. To increase the sensitivity of the index, the Doppler measurement must be performed near the fetal insertion, whereas a measurement near the placental insertion will make the Doppler examination more specific.

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).

Scintigraphic imaging due to its sensitivity is in many cases one of the most powerful techniques for demonstrating metastases. Severe limitations still exist in cancer when it is necessary to detect the presence of a few tumour cells in the residual minimal disease. In preliminary experiments it had been observed that an immunomodulator isolated from Nocardia bacteria (Nocardia Soluble Peptidoglycan Derivative: NSPD) electively bound to a model of activated macrophages. An hypothesis has been put forward that the enhanced detection of macrophages that are usually present in the vicinity or inside tumours should represent a polyspecific test for scintigraphy of a variety of metastases. NSPD radiolabelled with 99mTechnetium is not usable when injected intravenously due to its physiochemical properties. It has therefore been encapsulated into liposomes then administered via the respiratory tract as an aerosol. Amphiphilic properties, as well as its low molecular weight allow a rapid diffusion of NSPD in blood. Scintigraphy of metastases was possible from 1.5 to 6 hours after inhalation. The first stage of the study was carried out on 5 patients bearing known metastases (skin, lymph nodes, bone) from malignant melanoma that all were imaged with 99mTc-NSPD. The test was then applied to patients with a high risk of recurrent cancers (melanoma: 6, breast tumour: 7) based on the detection in their plasmas of high Lipid Associated Sialic Acid (LASA) concentrations. The association of these two sensitive techniques has resulted in the detection of very small metastases that were not seen using conventional scintigraphy; they were then confirmed histologically.

Pregnancies with a high risk of fetal growth retardation are at present watched by using clinical observations and biological parameters including ultrasound and estimation of the fetal heart rate. The Doppler waveform in the umbilical arteries provides information about circulatory resistance in the placenta. An index of resistance "R" is evaluated on the Doppler trace. The purpose of this study is to describe the score (with its possibilities and limitations) for this parameter "R" to follow-up pregnancies with fetal growth retardation and to compare it with ultrasound, biological and clinical parameters that are commonly used. Two groups of pregnancies have been explored: pregnancies with hypertension and pregnancies with idiopathic fetal growth retardation. Abnormal values of "R" correlate well with failure of fetal growth. Furthermore pathological values of "R" do not correspond to the same population as abnormal values of the other parameters. In some cases "R" is disturbed before the others are. In conclusion, this study shows that the index increases the accuracy of detection and the follow-up of chronic fetal growth retardation, particularly in cases of pregnancies with vascular placental pathology.

During normal pregnancies (n = 40) the cerebral index (Rc = S - D/S) (with S = systolic and D-telediastolic amplitudes) is always higher than the placental index (Rp), and the cerebro/placental ratio (Rc/Rp) greater than 1. Of 29 pregnant women with hypertension (including two twins), 17 delivered normally (Rc, Rp and CPR normal), 14 delivered an hypotrophic fetus, in 12 out of these 14 pregnancies one of the two indices (Rc or Rp) was abnormal and the cerebro/placental ratio, CPR, was always less or equal to 1. CPR sensitivity was 86% the specificity 100%. In 11 pregnancies with idiopathic fetal-growth retardation, the CPR was less or equal to 1 in eight cases (73% of the cases), and greater than 1 in three cases (three false-negative results).

Echotomography has been used for several years in routine for pregnancy follow-up. The morphological parameters provided by this technique (biparietal diameter, transversal abdominal diameter, length of the limbs...) give an objective information on the foetal growth. The exploration of foetal and placental circulation by Doppler measurement has been used in the past for the detection of the foetal cardiac rythm. The association of Doppler and echotomography allows to know precisely the location of vessels of interest, to quantify blood flow volume transcutaneously, and to determine an index of placental resistance. Recent improvements have simplified the use of this complex technique. Transducers for Doppler and imaging have been placed in the same probe very easy to handle. This system allows a precise localization of Doppler sample volume within the vessel to be explored. The great vessels can be studied all long the pregnancy. Normal Doppler spectrum of umbilical arteries shows an important diastolic flow. This fact is related to the low circulatory resistance of the placenta. When the placental circulatory resistances increase (because of placental infarcts for instance) the diastolic flow decreases in the umbilical arteries. To quantify this modification of umbilical circulation we used an index of the resistance (Pourcelot index) [9]: R = (formula; see text) [A systolic amplitude; D diastolic amplitude]. In normal cases, values of R decrease progressively during the course of the pregnancy. In case of abnormal pregnancies (dysgravidy) the index increases. Abnormal values of R had been correlated with hypotrophy or foetus death. With this duplex system it is also possible to determine the different parameters which are necessary to quantify the foetal blood flow in ml/mn. The first results obtained in dysgravidies confirm the major interest of blood flow study in follow-up and prognosis of high risk pregnancies.

Determination of the foetal sex in utero by ultrasonography is possible after the sixth month of pregnancy. In 100 women examined during the last trimester (15 with breech presentation and 85 with cephalic presentation) the sex of 28 boys and 34 girls could be diagnosed. This represents 72,9% positive determinations, if breech presentations are excluded. The best results are in fact obtained in cephalic presentations. One cause of error is spina bifida, which might give images resembling the scrotum (one case in our study). This examination is of interest mainly in cases of sex chromosome abnormalities.

Findings on ultrasound, arteriography and pathology examinations were compared in 49 patients undergoing 59 carotid endarterectomies between December 1981 and April 1983. Carotid artery lesions were investigated routinely by cervical Doppler, high resolution rapid ultrasound and either direct or more usually venous arteriography (with photographic subtractions). Postoperative endarterectomy specimens were examined to determine the exact degree of stenosis, and also qualitatively (gross pathology and histology of ulcerations and thromboses, the biochemical nature of the plaques, etc.). With respect to detection, that is demonstration of the existence or not of an atheromatous lesion, the ultrasonographic findings could always (100% of cases) be correlated with pathology data. Qualitative analysis of atheromatous lesions showed certain to be diagnosed with ease: calcified, fibrous or chondroid and lipidic plaques, while those complicated by hemorrhage, ulceration or mural thrombosis were less constantly diagnosed by ultrasound imaging. Occlusive plaques were easily detected, while recent intraluminal thrombosis was more difficult to diagnose by ultrasound alone. In this case the combined use of Doppler is a valuable aid, and is a routine procedure, in fact, in the department. Results of quantitative analysis showed good correlation between ultrasound and pathology findings in 79.7% of cases (insufficient in 20.3%). However, if ultrasonography is combined with other ultrasound methods of examination (standard Doppler and spectral analysis of Doppler) correlation is of the order of 95%, close to morphological data supplied by arteriography, with in addition a functional and qualitative approach not possible with arteriography alone.

Fetal cerebral arteries have been explored during normal pregnancies (n = 40). The index of cerebral resistance (Rc) as defined by Pourcelot (Rc = (S-D)/S where S is the systolic amplitude and D is the diastolic amplitude) shows variations similar to the placental index (Rp). During normal pregnancy, the cerebral index is higher than the placental index and the cerebro-placental ratio (Rc/Rp) is greater than one. This preliminary study of the umbilical and cerebral circulation during 21 pathological pregnancies with hypertension seems to demonstrate that when fetal growth retardation is also present (n = 6) either or both of the indices Rc and Rp may be outside the normal range but the cerebro-placental ratio (CPR) is always less than one. However, a larger number of patients needs to be explored in order to evaluate the clinical usefulness of such an observation.

The umbilical circulation can be investigated by Doppler ultrasound techniques very easily. The Doppler frequency spectrum from the umbilical arteries provides information on the placental circulation. The diastolic flow amplitude is directly related to the vascular resistances of the placenta (Rp). In cases of pathological pregnancies with hypertension the decrease of the diastolic flow and the increase of the resistance index Rp have been correlated with intrauterine fetal growth retardation. Fetal cerebral arteries have also been explored during normal pregnancies (n = 40). The index of cerebral resistance (Rc) as defined by Pourcelot is Rc = S-D/S (with S systolic amplitude and D diastolic amplitude) and shows variations similar to the placental index. During normal pregnancy, the cerebral index is higher than the placental index and the cerebro-placental ratio (Rc/Rp) is greater than 1. This preliminary study of both umbilical and cerebral circulation seems to demonstrate that during pathological pregnancies with hypertension (n = 21), with fetal growth retardation one of the indices, Rc or Rp may be out of the normal range but the cerebro-placental ratio (CPR) is always less than 1. However a larger number of patients should be explored in order to evaluate the clinical usefulness of such an observation.

Umbilical circulation can be explored by Doppler ultrasound methods very easily. The umbilical arteries spectrum provides information on the placental circulation. The diastolic flow is directly related to the vascular resistances of the placenta (Rp). In cases of pathological pregnancies with hypertension the decrease in the diastolic flow and the increase in the resistance index Rp have been correlated with intra-uterine fetal growth retardation. The specificity of this index Rp is of 95% but the sensitivity much more lower (approximately 70%). For that reason Doppler assessment of the fetal circulation in other areas has been recently carried out. Fetal cerebral arteries have been explored during normal pregnancies. The index of cerebral resistances as defined by Pourcelot Rc = S-D divided by S (with S systolic amplitude and D diastolic amplitude) show similar variations to the placental index but later in the pregnancy. During the pregnancy the cerebral index is higher than the placental one and the cerebro placental ratio (CPR) superior to 1. During pathological pregnancy (hypertension) with fetal growth retardation one of the index Rc or Rp may be out of the normal range but the cerebro placental ratio CPR is always lower than 1. The follow up of both the umbilical and cerebral circulation increases notably the accuracy of the Doppler method for the detection of intra-uterine fetal growth retardation.

This study was carried out on 49 patients who underwent an ultrasound study by continuous Doppler and echotomography B real-time, an angiography of supra-aortic arteries, and a carotid endarterectomy. Thirteen had had transient ischemic attacks and 20 a stroke. A quantification of the carotid stenosis in 4 stages was established for each method. For detection of lesion an excellent correlation was observed between the results of echotomography and pathology. For the quantification of lesion the correlation between echotomography and pathology was excellent also in 79,7 p. 100 of the cases, discordant in 20,3 p. 100. It was similar to the correlation between arteriography and pathology (excellent in 83 p. 100 of the cases). The correlation with pathology enabled to distinguish for stages of atherosclerotic lesions, to clarify their type of complications, and to evaluate their functional significance, particularly those with a high risk of embolism.

Leiomyoma of the kidney is a rare tumor, for which little investigational imaging data is available, and which is poorly characterized by histological methods. We are here concerned with one case that benefitted from an extensive radiological workup, and we provide a comparison with other cases mentioned in the literature.

Ultrasonographic examinations were conducted in one hundred patients with breast tumors (fifty cancers, twenty-five fibro-adenomas, and twenty-five cysts) using a manual apparatus and a 5 megahertz probe. Cysts are easily, diagnosed by ultrasonography if they are larger than 5 mm in diameter, but an equally effective result can be obtained by needle puncture. Results are less valid in fibro-adenomas (3 false positives), but this method is feasible in young women with radio-opaque breasts. Diagnosis by ultrasonography of breast cancers again depends on the size of the tumor (40 p. cent of false negatives in TI cases). The authors presently employ ultrasonography only for the diagnosis of solid, apparently non-malignant tumors, in young women (under 30 years) in whom mammography is ineffective, and for non-palpable radiologically detected opacities. New ultrasonography technics should enable improved results to be obtained when using non-invasive procedures for the diagnosis of breast tumors.

This study presents the preliminary results of systematic revascularisation of the left anterior descending (LAD) by the internal mammary (IM) artery. Between 1981 and 1983, 200 IM bypass procedures were performed (88.5% of bypassed LAD arteries during the same period). With experience, the contraindications of IM bypass surgery progressively decreased (none in the latter 100 cases). The IM bypass grafting was an isolated procedure in 35% of cases and associated with one or more saphenous vein (SV) bypass grafts in 64.5% of cases with an average of 1.9 grafts per patient. The surgical results were better than those of SV bypass grafting alone in the period 1978-1980 with a mortality of 2.5% and a perioperative infarction rate of 2.5% compared to 4.3% and 7% respectively. The medium term results (average follow up 2.5 years) show that more patients undergoing IM bypass surgery were asymptomatic (75%) than those undergoing SV bypass (46%). However, the patients operated more recently by IM bypass benefitted from the latest technical advances in bypass surgery. An unselected sample of 55 volunteers (out of 90 recalled patients) underwent angiography at 1 year. The patency rate was 93% with a very satisfactory angiographic appearance of the graft in nearly all patients suggesting the likelihood of a good long term result. It was possible to demonstrate graft patency by Doppler ultrasound and digitised intravenous angiography in some cases.(ABSTRACT TRUNCATED AT 250 WORDS)

A system for the exploration of deep vessels is proposed. This device is based on a single 300 element linear array in which a "Doppler area" is selected to electronically steer a Doppler beam. Characteristics of the equipment are excellent and it is as easy to handle as a simple linear array scanner. A real-time spectrum analyser is used to process the Doppler signals. The probe and the associated electronics are described and some results are given to illustrate the capabilities of the device such as blood flow estimation and deep vessel studies.