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Ultrasonography in patients with chronic liver disease: its usefulness in the diagnosis of cirrhosis.

OBJECTIVE: To prospectively assess the usefulness of ultrasonography in predicting the presence of cirrhosis in patients with asymptomatic chronic liver disease in unknown stage. EXPERIMENTAL DESIGN: Eighteen doppler and ultrasonographic features were prospectively assessed immediately before performing laparoscopy and/or liver biopsy. Usefulness of predictive variables selected by multiple regression analysis and included in a scoring scale was determined by ROC curves. PATIENTS: One hundred and thirteen consecutive patients with neither clinical nor biochemical signs of advanced liver disease submitted for study. RESULTS: Liver enlargement, liver surface nodularity, liver parenchyma distortion, flattening of flow wave in hepatic veins, portal and splenic veins dilatation, decreased variability in splenic vein caliber with breathing. Collateral vessels, and splenomegaly were associated to cirrhosis. Multivariate analysis showed the joint assessment of hepatic echostructure, portal vein caliber and spleen area to be the best approach to ultrasonographic staging, with sensitivity of 80%, specificity of 92% and accuracy of 89% in the diagnosis of cirrhosis. CONCLUSIONS: Ultrasonography enabled the presence or absence of cirrhosis to be correctly determined even in patients with asymptomatic disease. Combined assessment of hepatic echostructure, portal vein diameter and spleen size provides the highest accuracy.

Adolescent↗

CT angiography in the evaluation of acute stroke.

PURPOSE: To determine the worth of CT angiography of the circle of Willis as a supplement to routine CT in the examination of patients with symptoms of acute stroke in terms of its depiction of the number and distribution of arterial stenoses or occlusions. We also sought to compare the accuracy of CT angiography with MR angiography and/or digital subtraction angiography (DSA). METHODS: One hundred forty-five patients with symptoms of acute stroke were examined with routine head CT and CT angiography of the circle of Willis. MR angiography was also performed in 27 patients and DSA in 28 patients. CT and MR angiograms and DSAs were reviewed for stenoses or occlusions involving the vessels about the circle of Willis. MR and CT angiograms were also evaluated for image quality, and the corresponding routine CT and MR studies were evaluated for the presence of arterial infarction. RESULTS: CT angiograms were rated good or excellent in 89% of cases whereas MR angiograms were rated good or excellent in 92% of cases. Arterial stenoses or occlusions were present on 43% of CT angiograms, 48% of MR angiograms, and 21% of DSAs. Findings were in agreement in 98% of the vessels analyzed by CT angiography and MR angiography. Similarly, there was overall agreement of findings in 99% of vessels analyzed by CT angiography and DSA. None of the patients had any immediate adverse reactions after administration of intravenous nonionic iodinated contrast material. CONCLUSION: CT angiography is an accurate and safe method for evaluating arterial stenoses or occlusions in the vessels about the circle of Willis. CT angiography should be used in patients with symptoms of acute stroke for whom evaluation of the intracranial vasculature is desirable.

Adult↗

Color Doppler sonography of the hepatic artery and portal venous system.

Color Doppler sonography is an important noninvasive diagnostic tool for detecting abnormalities of the hepatic vasculature in patients with diffuse liver disease. To study its usefulness in these cases, we retrospectively reviewed the findings in 147 patients with abnormal portal venous color Doppler sonograms. This group comprised all patients with abnormal portal venous color Doppler sonograms studied from February 1987 to July 1989. Correlative imaging was not available in all cases. The sonographic diagnoses included (1) portal venous thrombosis (50 patients, 93 vessels); (2) portal-systemic or portal-portal collaterals (80 patients, 95 collaterals); (3) reversed, bidirectional, or other abnormal portal venous flow patterns (36 patients); and (4) abnormal hepatic arterial flow (20 patients). Since the results reported derive from a retrospective review without consistent correlation with other imaging studies, no appraisal of the sensitivity or accuracy of portal color Doppler sonography could be made from our data. The ability of color Doppler sonography to visualize flow without altering hemodynamics has led to several novel observations in these patients. These include increased arterial flow in states of low portal blood flow, reversal of portal flow direction postprandially, coincident reversed and hepatopetal flow in different branches of a single portal vein, and normal helical portal venous flow. These and other findings show that color Doppler sonography has enhanced our ability to detect abnormalities of the hepatic and portal venous system.

Collateral Circulation↗

Acute changes in systolic and diastolic events during clinical coronary angioplasty: a comparison of regional velocity, strain rate, and strain measurement.

Ultrasound-derived natural strain rate and strain are new Doppler myocardial imaging (DMI) parameters, which can measure local deformation independently of overall heart motion and thus could better characterize local contractility than DMI velocities alone. This study was undertaken to evaluate the relative benefits of regional velocity, strain rate, and strain measurements in detecting the range of acute changes in regional myocardial function in the "at-risk" zone during coronary angioplasty. Sixty-one patients (aged 63 +/- 12, 18 women) with stable angina pectoris were studied before, at the end of, and during recovery from a 60-second percutaneous transluminal coronary angioplasty (PTCA) balloon occlusion. High frame rate (147 fps) color DMI regional velocity data were derived from basal posterior (parasternal view) and mid, apical septal (apical view) "at-risk" segments as well as from the corresponding segments in healthy subjects and analyzed offline for velocity (VEL), strain rate (SR), and strain (epsilon) measurements. Coronary occlusion resulted in the reduction in VEL(SYS), SR(SYS), and epsilon(SYS) values for both radial (RCA/CX occlusion) and longitudinal data (LAD occlusion) in all segments analyzed. Velocity parameters alone failed to distinguish between baseline and occlusive measurements in the "at-risk" segments with visually abnormal baseline function. SR(SYS) and epsilon(SYS) had a higher diagnostic accuracy (sensitivity 75%, 80% and specificity 80%, 82%, respectively) than VEL(SYS) velocity alone (sensitivity 68%, specificity 65%,) for identifying acute ischemia in either baseline normal and abnormal segments. DMI-derived indexes can identify and quantify the spectrum of acute systolic and diastolic ischemic changes induced during clinical PTCA. The quantitation of regional deformation rather than motion would appear to be more appropriate in detecting and quantifying acute ischemic changes in myocardial function, especially in segments with pre-existing abnormal function.

Adult↗

Membrane properties and morphology of vasopressin neurons in slices of rat suprachiasmatic nucleus.

Vasopressin (VP) neurons in the suprachiasmatic nucleus (SCN) are thought to be closely linked to neural mechanisms for circadian timekeeping. To gain insight into the cellular-physiological principles that govern spike-driven VP release and to examine whether VP cells can be electrophysiologically and morphologically identified by a unique combination of features, we recorded membrane properties by whole cell patch-clamp methods and stained the cells with biocytin. In current-clamp mode, VP neurons recorded during subjective daytime expressed a clear time-dependent inward rectification but no pronounced low-threshold Ca2+ potential after hyperpolarizing current pulses. Their spontaneous firing rate varied between 0.6 and 13.4 Hz and was generally tonic and irregular. Spike afterhyperpolarizations (AHPs) were steeply rising and monophasic. Spikes were preceded by depolarizing ramps mediated by a slow component of Na+ current. Spike trains evoked by depolarizing current pulses displayed frequency adaptation and were usually followed by an AHP lasting 0.5-2.0 s. Spontaneous postsynaptic potentials were present in a majority of cells. Voltage-clamp recordings revealed a Ba2+-sensitive K+ current that exerts a tonic, hyperpolarizing influence on the membrane potential. This set of membrane properties was not significantly different from other cells in the dorsomedial region and is characteristic for cluster I cells, which were described previously and are widely encountered throughout the SCN. None of the cells could be classified as belonging to cluster II or III, which were indeed found mainly outside the dorsomedial region. Morphologically, single VP neurons were characterized by compact, mono- or bipolar dendritic branching patterns and numerous varicosities throughout the dendrites. They generally possessed few axon collaterals, most of which remained inside the boundaries of the SCN but were occasionally seen to project to SCN target areas. In conclusion, VP neurons in the SCN express several active membrane poperties, including time-dependent inward rectification, frequency adaptation in spike trains, monophasic spike AHPs, and Ba2+-sensitive K+ current. VP release is proposed to be governed by tonic and irregular patterns of spontaneous firing. The electrophysiological and cytological properties of VP neurons are representative for a majority of SCN cells and define them as a subset of previously defined cluster I cells.

Action Potentials↗

Accuracy of contrast-enhanced magnetic resonance angiography in chronic thromboembolic disease.

RATIONALE AND OBJECTIVES: We evaluated the accuracy of contrast-enhanced magnetic resonance (MR) angiography in demonstrating the findings of chronic pulmonary thromboembolism (CPTE) compared with conventional pulmonary angiography. METHODS: We examined 18 patients with CPTE proved by conventional pulmonary angiography and 16 healthy control patients. T1-weighted and single-breathhold, two-dimensional multiplanar spoiled gradient-recalled pulmonary images were obtained after injection of gadopentetate dimeglumine. Images were interpreted independently by two radiologists. RESULTS: All patients with CPTE were identified on MR angiography images by both readers. Sensitivity and specificity for MR angiography in diagnosing abnormal segments were 76% and 95% for reader 1 and 68% and 93% for reader 2, respectively. Sensitivity and specificity for MR angiography in depicting abnormal lobes were 83% and 96% for reader 1 and 82% and 93% for reader 2, respectively. Interobserver agreement was high; kappas for abnormal segments and abnormal lobes were .72 and .84, respectively. The T1-weighted spin-echo images demonstrated a mosaic signal intensity pattern in all patients with CPTE. CONCLUSION: Contrast-enhanced MR angiography accurately depicts abnormal segments and lobes in occlusive vascular disease and clearly distinguishes between patients with CPTE and those with healthy lungs.

Chronic Disease↗

Analysis of strain distribution in the medial collateral ligament using a photoelastic coating method.

The strain distribution over the entire medial collateral ligament (MCL) was measured using a photoelastic coating method. This new approach utilized a polyurethane monomer as a photoelastic coating film. The initial experiments investigating MCL strain measurement showed that this film had a high sensitivity for strain and good adhesion to the ligament. It was confirmed that strain distribution could be obtained qualitatively over the entire ligament using this method. The mechanism of MCL injury was studied by applying this polyurethane coating film to the entire MCL in a femur-MCL-tibia complex. When simple tension was applied to the complex, strain concentrations were centred at the tibial insertion site, and all the specimens ruptured at the MCL tibial insertion site. With application of a valgus bending moment, increased strain was seen in the MCL from the medial femoral condyle to the medial epicondyle. Histological analysis demonstrated midsubstance ligament ruptures in this same region. For both tests, rupture sites and increased strain concentration sites correlated. In addition, an impingement phenomenon of the MCL on the medial femoral condyle can be seen during application of valgus force, and this phenomenon may explain the higher incidence of MCL injuries on the femoral side seen in the clinical setting. This polyurethane coating method allows for direct and visual measurements, and can qualitatively measure the strain behaviour over the entire MCL surface. This new technique represents a significant improvement over previous point-by-point strain measurement methods.

Animals↗

Multilevel somatosensory evoked potentials (SEPs) for spinal cord monitoring in descending thoracic and thoraco-abdominal aortic surgery.

The usefulness of somatosensory evoked potential (SEP) monitoring as a means of preventing paraplegia in descending aorta surgery was evaluated in 47 consecutive cases operated on for isthmic (14 cases), thoracic (22 cases), or thoraco-abdominal (11 cases) repair. An aortic dissection was found in 11 cases (acute in 6). Somatosensory evoked potentials were obtained by unilateral left and right posterior tibial nerve (PTN) stimulation at the ankle and recordings were performed on four channels: peripheral nerve, lumbar spinal, brain-stem, and cortical recordings. Our experience led to the following current strategy: the establishment of atrio(aorto)-femoral(aortic) bypass (29 cases), proximal and distal aortic cross-clamping, aortic repair with reimplantation of the culprit artery(ies) as indicated by SEP alterations. Five types of SEP alterations were defined on the basis of the neural level involved: type I (27.7% of cases) = distal spinal ischemia due to proximal aortic cross-clamping in the absence of bypass; type II (21.3%) = PTN ischemia due to left common femoral artery cross-clamping; type III (12.8%) = segmental spinal ischemia due to the exclusion of critical feeding arteries; type IV (4.3%) = ischemia in the left carotid artery territory; type V (4.3%) = global brain hypoperfusion due to systemic hypotension. Forty-five patients survived the operation and could be tested for neurological dysfunction. Three patients presented a postoperative spinal cord deficit, but this deficit was already present preoperatively in one case, so that the actual incidence of a new paraplegia in our series was 2/45 cases (4.4%). One of the two cases was clearly a delayed paraplegia with SEP alterations appearing several hours after the operation. Somatosensory evoked potentials were evaluated on the basis of their sensitivity, specificity, and impact on the surgical strategy. Regarding SEP sensitivity, we did not encounter any unexpected immediate paraplegia, but the critical factor appeared to be the duration of SEP absence due to spinal cord ischemia, which, according to the literature, should never exceed 30 min; after a longer absence, SEP return does not guarantee neurological recovery. Somatosensory evoked potential specificity was also 100%, but only 58% of the abnormalities found were actually consequent to spinal cord ischemia, the rest of the abnormalities being consequent to peripheral nerve or brain ischemia. Finally, SEP monitoring had a significant impact on surgical strategy in 19% of the cases. It is concluded that distal aortic perfusion and multilevel SEP monitoring play a significant role in preventing paraplegia in descending aorta surgery.

Adolescent↗

Structure-function relationships in rat brainstem subnucleus interpolaris. I. Vibrissa primary afferents.

Intra-axonal recording and horseradish peroxidase labelling techniques were used to examine structure-function relationships for vibrissa-sensitive primary afferent fibers (N = 40) in rat trigeminal brainstem subnucleus interpolaris (SpVi). All responded at short (mean-0.42 ms) latencies to trigeminal ganglion shocks and to innocuous stimulation of an individual vibrissa in a slowly adapting type I, slowly adapting type IIa, slowly adapting type IIb, low-velocity-sensitive rapidly adapting, or high-velocity-sensitive rapidly adapting fashion. As in the medullary dorsal horn (Hayashi, '82; Jacquin et al., '86a), functionally distinct mystacial vibrissae-related fibers were morphologically indistinguishable. Each gave rise to up to ten collaterals that entered interpolaris perpendicular to the long axis of the nucleus and often overlapped to form a densely packed, highly circumscribed, and largely continuous column of terminal arbors. While some morphological variability was observed both within and between individual axons, variance within a given functional class was no greater than that between classes. Nonmystacial vibrissae afferent arbors also formed similar ovoid, dense circumscribed terminal plexuses. Presumably, these individual arbors collectively form a longitudinal tubelike vibrissae representation in this and other components of the trigeminal brainstem nuclear complex. The relative locations of each fiber's terminal field could be accurately predicted by the particular vibrissa innervated. Contrary to previous data obtained with similar methods (Hayashi, '82), but consistent with the findings of earlier transganglionic tracing (Arvidsson, '82) and histochemical (Belford and Killackey, '79) studies, the arbors of these fibers terminated throughout the mediolateral extent of SpVi. Axons innervating rostral vibrissae terminated medially, and those that supplied caudal vibrissae innervated the lateral SpVi. Dorsal vibrissae were represented in the ventral SpVi, while ventral vibrissae were represented more dorsally. This transverse topography extended largely throughout the rostrocaudal extent of interpolaris. In summary, the vibrissae primary afferent map in SpVi is inverted, faces medially, and is rostrocaudally consistent. In its most caudal aspect, as the displaced substantia gelatinosa swings laterally, the map is less orderly and incomplete. These generalizations also apply to the nonmystacial vibrissae afferents.

Adaptation, Physiological↗

Septo-hippocampal deafferentation protects CA1 neurons against ischemic injury.

Excessive synaptic excitation caused by transient cerebral ischemia has been proposed to explain the greater vulnerability of specific neuronal populations to ischemic injury. We tested this hypothesis in rats by cutting, alone or in combination, the afferent fibers that travel in the fimbria/fornix, the perforant, or the Schäffer collateral pathways and innervate the right CA1 hippocampus. Seven to twelve days later the animals were subjected to 30 min of reversible forebrain ischemia. Irreversible damage to the CA1 neurons was assessed with the light microscope after 70-120 h of cerebral reperfusion. The left, unlesioned hippocampus served as a control. Simultaneous cutting of the 3 major afferent pathways significantly reduced CA1 neuronal damage compared to the unlesioned side (P less than 0.001) or to sham-lesioned controls (P less than 0.001). Selective lesions of the fimbria/fornix but not the perforant or the Schäffer collateral pathways also protected against ischemic CA1 damage. These data indicate that afferent fiber input modulates hippocampal damage caused by ischemia, but they are inconsistent with the hypothesis that excitatory afferent fibers, travelling in either the perforant or the Schäffer collateral pathways alone, play a major role. Neurotransmitters, other than those activating excitatory amino acid receptors or yet-to-be-identified synaptic events, may be invoked to explain the spatial and temporal sensitivity of hippocampal CA1 neurons to ischemia.

Animals↗

BSO-induced reduction of glutathione levels increases the cellular radiosensitivity of drug-resistant human tumor cells.

Acquired resistance to cis-platinum and melphalan, in the human ovarian OAW42 tumor cell line, respectively, conferred a 3- and 1.5-fold decrease in photon sensitivity. Analysis of cell survival curves by the linear quadratic equation showed an accompanying 5- and 2-fold reduction in the magnitude of the initial slope (alpha). Treatment with the GSH depleting agent BSO restored the magnitude of alpha to a value similar to that of the parental line without evidence of dose modification in the high-dose region of the cell survival curve. This in conjunction with failure of alteration in GSH levels to affect parental OAW2 sensitivity and of the SER of BSO to reflect GSH levels suggest a possible GSH independent mechanism of action for BSO. If similar patterns occur in the clinic, the possibility exists of circumventing collateral resistance between chemotherapeutic agents and ionizing radiation, provided that tumor thiol levels can be preferentially depleted.

Buthionine Sulfoximine↗

Duplex-Doppler ultrasonography in the assessment of portal hypertension. Utility of the measurement of maximum portal flow velocity.

To assess the utility of Duplex-Doppler ultrasonography (DDUS) in the evaluation of portal haemodynamics we studied 52 patients with compensated liver cirrhosis (mean age 53.9 +/- 9.2 years, males 32, females 20) diagnosed by laparoscopy and biopsy. All patients underwent laparoscopy and oesophageal-gastro-duodenoscopy (OGDS): we postulated that haemodynamically significant portal hypertension (PH) was present if varices were detected at OGDS and/or if collateral veins were revealed at laparoscopy. DDUS was performed with a strictly standardized method and maximum portal flow velocity (PFV) was measured in all patients. Max-PFV ranged between 3.5 and 33.4 cm/s. Overall, 36 patients (69%) had a max-PFV lower than 20.3 cm/s (normal max-PFV range in our laboratory is 20.3-33.3 cm/s), while 16 patients (31%) had normal max-PFV values. Five patients (9.6%) had no signs of PH at laparoscopy and/or OGDS and all five had normal max-PFV values. The other 47 patients (90.4%) had collateral circuli at laparoscopy and 29/47 (61.7%) exhibited also varices at OGDS: max-PFV was lower than 20.3 cm/s in 36/47 patients (76.6%). The measurement of max-PFV demonstrated a 76.6% sensitivity and a 100% specificity in detecting PH, with 100% positive predictive value and 31% negative predictive value. Three patients with PH and apparently normal max-PFV values exhibited a recanalization of the umbilical vein.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity↗

Continuous 12-lead ST-segment recovery analysis in the TAMI 7 study. Performance of a noninvasive method for real-time detection of failed myocardial reperfusion.

BACKGROUND: If a practical, reliable, noninvasive marker of failed reperfusion was available in real time, the benefits of further therapy in this patient subgroup could be tested. We developed a method of 12-lead ST-segment recovery analysis using continuously updated reference points to provide such a marker. METHODS AND RESULTS: In this study, our method was prospectively tested in 144 patients given thrombolytic therapy early in myocardial infarction. All patients had 12-lead continuous ST-segment monitoring and acute angiography, each analyzed in an independent, blinded core laboratory. ST-segment recovery and re-elevation were analyzed up to the moment of angiography, at which time patency was predicted. Predictions were correlated to angiographic infarct artery flow, with TIMI flow 0 to 1 as occluded and TIMI flow 2 to 3 as patent. Infarct artery occlusion was seen on first injection in 27% of patients. The positive predictive value of incomplete ST recovery or ST re-elevation by our method was 71%, negative predictive value 87%, with 90% specificity and 64% sensitivity for coronary occlusion. ST recovery analysis predicted patency in 94% of patients with TIMI 3 flow versus 81% of patients with TIMI 2 flow and predicted occlusion in 57% of patients with collateralized occlusion versus 72% of patients with non-collateralized occlusion. In a regression model including other noninvasive clinical descriptors, ST recovery alone contained the vast majority of predictive information about patency. CONCLUSIONS: In a blinded, prospective, angiographically correlated study design, 12-lead continuous ST-segment recovery analysis shows promise as a practical noninvasive marker of failed reperfusion that may contribute substantially to currently available bedside assessment. Our data also suggest that patients with TIMI 2 flow or with collateralized occlusions may represent a physiological spectrum definable with ST-segment recovery analysis.

Adolescent↗

A digital splenoportography: more sensitive method of detecting spontaneous splenorenal shunt.

Splenoportography was performed upon 195 pediatric patients, including 137 by conventional technique and 58 by digital subtraction technique. The results obtained were compared, and it was found that the percentage of diagnosis of spontaneous splenorenal shunt was higher with digital than with conventional technique. In conclusion digital technique is a more sensitive and safer method than the conventional method.

Angiography, Digital Subtraction↗

Phylogenetic aspects of the neuroepithelial bodies.

Neuroepithelial bodies (NEB) are small groups of cells bound together by desmosomes and which form part of the epithelium lining the bronchopulmonary ducts. The cells have an irregular, columnar shape often with laterally placed microvilli and unspecialized cytoplasmic protrusions into the intercellular spaces. Their most distinctive cytoplasmic feature is the numerous dense cored vesicles (DCV) located towards the basal region of each cell. A variety of peptides and the monoamine serotonin are distributed within these DCV. Evidence has been shown for the occurrence of more than one type of DCV for the co-existence of various peptides and serotonin in the same DCV and for morphological and functional variations in cells forming a NEB. In some animals the apical pole is in direct contact with the lumen of the duct, whereas in others the NEB is isolated from the lumen by either ciliated epithelial or Clara-like cells. When the apical pole contacts the lumen, the surface of each cell bears microvilli and occasionally a single cilium. The NEB of eutherian mammals are sensitive to a number of experimental procedures including hypoxia, hypercapnia and vagal stimulation. Experimental lesions above and below the nodose ganglion have shown that the major part of the innervation is afferent with collateral branches off the afferent forming efferent, cholinergic endings. A small efferent input is also derived directly from the central nervous system. These studies suggest that a minor component of the efferent innervation is derived contralaterally or from intrapulmonary ganglia. Other forms of innervation identified by transmission electron microscopy in some mammals and lower vertebrates include cholinergic reciprocal synapses, adrenergic and peptidergic nerve junctions.(ABSTRACT TRUNCATED AT 250 WORDS)

Amphibians↗

Contrast enhanced sonography of visceral perfusion defects in dogs.

The purpose of this study was to assess the utility of an intravenous contrast agent (FS069) for visualization of normal visceral perfusion compared with perfusion after segmental infarction in a canine model. Six mongrel dogs were used as subjects. Splenic, renal, hepatic, and small bowel perfusion was assessed without and with intravenous microbubble contrast material using gray scale, color Doppler, pulsed Doppler, and color power Doppler sonography. Each organ was then reassessed after ligation of a segmental vessel. Imaging was again performed without and with contrast material using all four ultrasonographic modalities. In all organs color and spectral Doppler signals were significantly enhanced from normally perfused tissue after intravenous contrast agent injection. Ischemic areas were more conspicuous after contrast medium injection except in the liver. Hepatic perfusion was maintained by portal flow in the liver despite arterial ligation. Ligation of collateral arcades was required to produce bowel ischemia. Intravenous injection of FS069 improves evaluation of visceral perfusion and identification of focal visceral ischemia in dogs. These results suggest that this agent may increase sensitivity for detection of blood flow in small and deep vessels.

Albumins↗

[The echo-dobutamine test for the diagnosis of myocardial ischemia. Study on 20 patients with normal kinetics at rest].

We have assessed the value of dobutamine stress echocardiography for the diagnosis of myocardial ischemia in 20 consecutive patients referred for chest pain, without a previous myocardial infarction and with a normal left ventricular wall motion at rest. The test was considered positive when wall motion abnormalities appeared during dobutamine infusion (from 5 to a maximum of 40 micrograms/Kg/min). The results were compared to the % diameter stenosis (%DS) quantitatively measured on coronary arteriography. "Significant" coronary artery disease was defined as greater than or equal to 50% DS. No significant side effects occurred in any patients during the test. Transient wall motion abnormalities were detected in 8 of the 12 patients with significant coronary artery disease (sensitivity = 66%) and in 1 of the 8 patients without significant coronary artery disease (specificity = 88%). All the patients with false-negative dobutamine stress echocardiography had distal stenosis or stenosis in a collateral vessel; moreover, all the patients with true-positive dobutamine stress echocardiography had proximal (7 patients) or middle (1 patient) stenosis. The results of this study show that dobutamine stress echocardiography is a safe and feasible test for the noninvasive diagnosis of myocardial ischemia.

Adult↗

Sensorimotor stimulation of comatose patients.

Coma is a state of unconsciousness from which the patient cannot be aroused. The causes of coma are classified into structural and nonstructural disorders. The depth and duration of post-traumatic consciousness disorder are a sensitive and reliable indicator of the severity of head trauma. The social prognosis aggravates with age and duration of unconsciousness. Early sensorimotor stimulation by adequate series of stimuli paves the road for new collaterals of the weakened and lost neurons, and for their connection. In such a way. the entire system of structures required for successful regeneration and reorganization of functions in the damaged parts of the brain is maintained in a relatively functional tone. This is substantiated by two examples taken from practice, presented as brief case reports.

Adult↗