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Biomedical subjects

A Constantinesco

Publications and source records attributed to A Constantinesco.

At least 55 records · Page 3Linked to original sources
PubMed1989

[Monoclonal anti-AFP immunoscintigraphy of human hepatocellular carcinoma. Influence of biological, anatomical and vascular factors].

The actual interest of immunoscintigraphy for the detection of alphafetoprotein-producing liver tumors was investigated by both visual examination and quantitative analysis in 61 patients with either hepatocellular carcinoma (39 patients, group I), secondary liver cancer (11 patients, group II), or non tumoral liver (9 cirrhosis, 2 healthy liver, group III): All patients received injections of 123I-anti-alphafoetoprotein monoclonal antibodies and planar scans were performed after 28 hours. Only 18 out of 39 hepatocellular carcinoma-bearing patients had a positive scan (46 p. 100). Such a moderate sensibility was due to a striking inhibitory influence of cirrhosis: the positivity rate was 6/24 and 12/15 respectively when hepatocellular carcinoma was and was not associated with cirrhosis (p less than 0.01). Specificity was also moderate (55 p. 100) for detection of hepatocellular carcinoma in tumor-bearing patients (group I and II). In the absence of cirrhosis, the intensity of the tumoral uptake was highly correlated with high serum alphafoetoprotein level (p less than 0.001) and tumor arterial hypervascularization (p less than 0.01). Anti-alphafoetoprotein monoclonal antibody uptake by the extratumoral liver was found to be very specific of hepatocellular carcinoma since it was high in 23 out of 39 patients of group I but in only 1 out of 22 in groups II and III (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Is anti-alphafetoprotein immunoscintigraphy a promising approach for the diagnosis of hepatoma? Implications of a quantitative study in 41 patients.

The actual interest of immunoscintigraphy for the detection of liver tumours was investigated by both visual examination and quantitative analysis in 41 patients with hepatoma (HCC, 21 cases, 13 AFP-secreting), other primary or secondary liver cancer (9 cases), testicular cancer (2 cases) and cancer free cirrhosis (9 cases). All patients were injected with 123I-anti-alphafetoprotein (AFP) monoclonal antibodies (MAbs) and scans were performed after 28 +/- 2 h. In the hepatoma-bearing patients, 11 positive anti AFP scans were found; 9 of them had an enhanced serum; besides, 3 non HCC tumours were also detected. With respect to hepatoma diagnosis, sensitivity was 52.5% and specificity 66.5%. For all hepatomas, it was striking that the positivity rate was 2/10 and 9/11, respectively, when HCC was and was not associated with cirrhosis. Among 6 patients with a positive anti AFP scan who were also injected with control anti hCG 123I-MAb, 5 positive anti hCG scans were surprisingly found, with specificity indices ranging between 1.00 and 1.75. The quantitative study also highlighted the importance for hepatoma detection of specific and non specific factors such as serum AFP, tumoural vascularization, non tumoural liver uptake and intrahepatic distribution of HCC. Anti AFP immunoscintigraphy appears as a poorly sensitive and moderately specific method for hepatoma diagnosis. In contrast, non tumoural liver uptake level could be more useful for discriminating HCC from liver metastases and perhaps to detect the early extension of HCC.

Adult↗
PubMed1988

Detection of myocarditis during the first year after discovery of a dilated cardiomyopathy by endomyocardial biopsy and gallium-67 myocardial scintigraphy: prospective multicentre French study of 91 patients.

The purpose of this study was to assess the frequency of inflammatory lesions in the myocardium of subjects with dilated cardiomyopathy and to determine if there was any correlation between the results of two methods of evaluation, one (endomyocardial biopsy) invasive and the other (gallium-67 scintigraphy) noninvasive. Of 115 subjects recruited in seven centres, 91 met the inclusion criteria (left ventricular dilatation greater than or equal to 100 ml m-2 and ejection fraction less than 55% with normal coronary arteriography) and had endomyocardial biopsy (mean five specimens) and Ga-67 myocardial scintigraphy after several days. Scanning was considered doubtful 19 times and positive 13 times. The histologic count of mononuclear cells in the myocardial interstitium in 20 fields was greater than 5 cells field-1 in only four cases. No correlation was found between the two methods. Subjectivity in the choice of the criterion of positivity of Ga-67 scintigraphy and difficulties in identifying lymphocytes upon pathological examination were the major problems encountered. Despite limitations, both techniques suggest that cellular infiltrates are minimal and quite infrequent in dilated cardiomyopathy.

Adolescent↗
PubMed1988

[Revascularization in the acute phase of myocardial infarction. Study of left ventricular function in the 3d week and 6th month].

27 patients with primary myocardial infarction are treated, in the first 6 hours, with intravenous thrombolysis with immediate coronary angiographic control showing a patent artery in 76 p. cent of the cases. The treatment is completed with intracoronary thrombolysis (5 times) and transluminal angioplasty (6 times), enabling to obtain a patency rate of 88 p. cent. The overall left ventricular function is evaluated at D21 and in the 6th month (M6). Among anterior infarctions, those treated during the first three hours have a better ejection fraction (EF) at D21 than those treated later (40.3 p. cent +/- 6 versus 33.2 p. cent +/- -NS); this functional benefit is confirmed at M6 (42.8 p. cent +/- 12 versus 30.6 p. cent +/- 8; p less than 0.06). On the contrary, among inferior infarctions, the EF is comparable at D21 and M6 regardless of the early nature of the treatment. One patient died prematurely from a cerebral vascular accident which occurred during the thrombolysis. These results are in favor of a significant myocardial salvation in anterior infarctions revascularised at an early stage and of an active approach in order to obtain the most complete possible revascularisation.

Angioplasty, Balloon↗
PubMed1988

[Modifications in the contraction and relaxation of the left ventricle in chronic ischemic cardiopathies. Study using equilibrium angio-scintigraphy].

Our purpose was to confirm that abnormalities of left ventricular filling, which are associated with abnormalities of contraction, play an important part in the genesis of cardiac failure in chronic ischaemic heart disease. We used equilibrium radionuclide angiography of the cardiac cavities to study the behaviour of the left ventricle during contraction and relaxation in three groups of patients: a control group of 15 patients without cardiac disease (G2), and a group of 28 patients with chronic ischaemic heart disease complicated by cardiac failure (G3). From the overall activity-time curves and their first derivatives were calculated the ejection fraction, the peak ejection rate and the peak filling rate, as well as the time in the cardiac cycle when these appeared, the reference point in time being the end-diastole. Separately, an analysis of spatial distribution, pixel by pixel, of the elementary values of these times was developed with the help of new functional images constructed, pixel by pixel, from the first derivatives of the activity-time curves. These functional images were exploited by calculating histograms of times, and the width of the bars at mid-height was taken as the dispersion parameter expressed as a percentage of the cardiac cycle. There was a significant reduction of ejection fraction in groups G2 (49.8 +/- 11.6 p. 100) and G3 (36.3 +/- 15.4 p. 100) as compared to control group G1 (60.3 +/- 8.4 p. 100) (G1-G2 p less than 0.05; G2-G3 p less than 0.001; G1-G3 p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Three-phase bone scanning in reflex sympathetic dystrophy of the hand.

Three-phase bone scanning was performed in 181 patients suffering from reflex sympathetic dystrophy (RSD) of the hand. Four quantitative parameters were defined as follows: (a) hemovelocity and (b) blood pool (determined from the Fourier processing of angiographic data); (c) early (3-5 min) and (d) delayed (2-3 hr) bone fixation. Three significant stages of RSD were demonstrated scintigraphically. Stage I (0-20 wk from onset) demonstrated increases in velocity, blood pool, and early and delayed fixations. At stage II (20-60 wk) blood velocity and blood pool were normalized, but early and delayed hyperfixation persisted. During stage III (60-100 wk) blood velocity and blood pool were reduced on the affected hand, and early and delayed fixations were normalized. Such abnormality of decreased hemodynamic parameters may become associated with bone hypofixation in stage III. Early treatment of RSD (as compared with delayed treatment) has been demonstrated to induce normalization of hemovelocity (p less than 0.05), blood pool (p less than 0.02), and joint stiffness (p less than 0.001) without any change in the bone fixation; therefore, three-phase bone scanning may provide useful information regarding the pathophysiologic and clinical evolution of RSD.

Bone and Bones↗
PubMed1987

[A multidisciplinary approach to algodystrophy of the hand].

A multidisciplinary approach for the management of reflex sympathetic dystrophy at SOS Main of Strasbourg has been progressively adopted due to the severe functional sequelae of this disease. The TC99 bone scan in three phases has allowed us after a one week duration of the symptoms to make an early diagnosis and to start dynamic splinting in flexion. Our study compares two groups of patients, one with an early treatment and the other with delayed treatment. It shows a correlation between the stiffness of the affected hand and the isotopic findings. The benefit from an early dynamic splinting in flexion as evidenced by a clinical improvement is corroborated by the bone scan.

Combined Modality Therapy↗
PubMed1987

[Scintigraphy and esophageal pH measurement in adults with gastroesophageal reflux].

Thirty-seven adults with gastroesophageal reflux were explored by gastroesophageal scintigraphy and pH monitoring (three hours postprandial). Scintigraphy was less frequently positive than pH test in gastroesophageal reflux (81% versus 57%) with a significant difference. It is suggested that postprandial pH monitoring is reliable in the initial assessment of symptomatic gastroesophageal reflux.

Adult↗
PubMed1987

[Developmental profile of scintigraphic parameters within 3 weeks following primary myocardial infarction without any attempt at revascularization].

30 patients with a transmural primary myocardial infarction conventionally treated, are explored by myocardial scintigraphy using thallium 201, and calculation of a lesional score (L.S) and angio-scintigraphy on the first day (D1) and at three weeks (D21). The results of these examinations are compared to those of coronography at D21. Anterior necroses present a myocardial fixation defect and a dysfunction of the left ventricle which are more severe than in inferior necroses. Patients with a marked fixation defect (L.S 2) at D1, present a low ejection fraction (EF) becoming significantly worse at D21. Coronary permeability is accompanied by an appreciable improvement of the myocardial fixation from D1 to D21 and a stability of EF. On the contrary, if the occlusion persists, the fixation defect is stable and the EF decreases significantly. In this study, the coronary permeability appears to be associated to a perservation of the ischemic myocardium which may only be demonstrated by knowing the evolution of the various parameters during the first three weeks of the infarction.

Coronary Angiography↗
PubMed1986

Three phase bone scanning as an aid to early diagnosis in reflex sympathetic dystrophy of the hand. A study of eighty-nine cases.

In reflex sympathetic dystrophy, three phase radionuclide bone scanning with Tc-99m methylene diphosphonate is preferred. The first phase corresponds to the dynamic behavior of the tracer. After appropriate data processing (by Fourier's analysis), three functional images may be obtained. The second phase corresponds to the tissues fixation of the tracer 5 to 10 minutes after the injection. Based on the results of 89 cases of post-traumatic or postsurgical reflex sympathetic dystrophy observed in 128 patients investigated with this method, diagnostic sensitivity was 96%, while specificity was 86%. The scintigraphic patterns observed during the 100 week period after the initial trauma demonstrate the precocity and the significance of circulatory and tissues phenomena as well as their variations according to treatment. The scintigraphic criteria of regression or stabilization of disease are discussed.

Adolescent↗
PubMed1985

[Flow analysis by phase modulation of NMR signals].

Time modulated field-gradient-sequences able to selectively phase encode spatial location or flow velocity in NMR signals are described. The specific phase modulation discriminates between stationary and mobile protons. The method is presented in the one dimensional case and has the following advantages: it is sensitive to flow direction and unaffected by the relaxation times.

Magnetic Resonance Spectroscopy↗
PubMed1984

Spatial or flow velocity phase encoding gradients in NMR imaging.

We describe time modulated field gradient sequences able to selectively phase encode spatial location or flow velocity in NMR Signals. Two flow conditions are presented: constant flow velocity and simple harmonic flow superposed on steady flow. In each case we show that specific modulated gradients are available in order to discriminate between stationary and mobile protons. The methods are presented in the one dimensional case. The advantages of the phase modulation for flow analysis are the following: the method is sensitive to flow direction, unaffected by the T2, and the stationary and flow parameters are quantifiable factors.

Blood Circulation↗
PubMed1981

Evaluation of myocardial perfusion and left ventricular function by 201T1 scintigraphy after dipyridamole.

201T1 myocardial imaging was performed at rest and after dipyridamole (0.44 mg/kg) on 50 patients with known or suspected ischemic heart disease. The dipyridamole had no effect in 14 patients (group Dip.0). In 17 patients (group Dip +/-) it significantly modified the contrast of the rest image (by increasing or decreasing a rest perfusion defect). In 19 patients (group Dip - Steal) the drug induced a paradoxical response interpreted as a coronary steal effect (an active region at rest becomes hypoactive after dipyridamole while an underperfused region at rest improves). All patients underwent coronary arteriography and left monoplane ventriculography; results were interpreted in relation to these angiographic data. The mean percentage of stenoses (per patient) was about the same in the three groups but it was found that, despite these stenoses, the patients of the group Dip - Steal had a good left ventricular function (EF = 0.62 +/- 0.12). On the other hand, the ejection fraction was very poor in the two other groups (0.50 +/- 0.17 and 0.48 +/- 0.17). Moreover it was found that: (1) the frequency of high grade or even complete obstruction was notably less in group Dip - Steal (P less than 0.05); (2) the frequency of angiographically visible collaterals was higher in group Dip - Steal (P less than 0.05); (3) the left anterior descending artery was less diseased than the right coronary artery in group Dip - Steal (P less than 0.05). These results have a real prognostic value for the assessment of the preserved cardiac performance in Dip - Steal patients despite severe stenoses, and are discussed in terms of compensatory collateral circulation and preservation of the coronary-flow reserve in the myocardium distal to a critical stenosis.

Coronary Circulation↗