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P J Bernard

Publications and source records attributed to P J Bernard.

At least 19 recordsLinked to original sources
PubMed1997

[Quantification of mitral regurgitation by cine-MRI. Comparison with transesophageal echocardiography in 45 patients].

Cine-MRI demonstrates the presence of mitral regurgitation by a signal void. This study was undertaken to assess the value of this method for quantification of mitral regurgitation in a population not excluding either patients with mitral valve prostheses or those with atrial fibrillation. The subjects included had a mean age of 59 years and were referred for transoesophageal echocardiography, either for assessment of valvular heart disease (38 patients), or for detection of atrial thrombosis before external electrical cardioversion (7 patients). Eight patients had mitral valve prostheses and 19 were in atrial fibrillation. Cine-MRI was performed within 12 days of the transoesophageal echocardiography study with a 1.5 tesla magnet, using a sequence of gradient echo in 3 parallel planes in the 4 chamber view. The regurgitation was quantified by MRI from the extension of the signal void in the left atrium. The transoesophageal Doppler echocardiographic criteria were the width of the regurgitant jet at its origin, the intensity of the regurgitation signal recorded by continuous wave Doppler and the extension of the jet within the left atrium. The quantification by degrees 1 to 4 did not differ by more than 1 degree between the 2 techniques in 43 of the 45 patients. Out of 4 left atrial thrombus detected by transoesophageal echocardiography, only 1 was visible by MRI. The authors concluded that quantification of mitral regurgitation by cine-MRI provides similar results to those obtained by transoesophageal echocardiography and that the correlation remains valid in cases of atrial fibrillation. However, Doppler echocardiography provides further valuable information for the clinician.

Aged↗
PubMed1996

[Magnetic resonance angiography. Value for evaluating the patency of aortocoronary bypass].

OBJECTIVE: Assessment of coronary bypass patency with conventional angiography can be limited by difficulties in selective catheterism. The aim of this work was to determine whether ultrarapid sequences proposed for imaging coronary arteries could be used to evaluate bypass patency. METHODS: Twenty patients (mean age 66 +/- 7 years) with 42 aorto-coronary bypasses (32 venous and 10 mammary bypasses) underwent conventional angiography and magnetic resonance angiography within a 1 week interval. All patients were evaluated 1 to 15 years after bypass surgery. Magnetic resonance imaging (MRI) was performed in ventral supine position using a flexible surface coil. Breathhold electrocardiogram-synchronized sequences were acquired using a 1.5 T magnet, with TR = 156 ms, TE = 8 ms, slice thickness 5 mm, 126.256 matrix, and a 7 to 11 segmentation per cardiac cycle. At most, 24 transverse slices were acquired for each patient. RESULTS: Twenty-six patent bypasses were correctly identified with MRI. Three bypass were patent on angiography and appeared occluded on MRI (2 mammary and 1 venous bypass). Nine bypasses were classed as occluded with both techniques. MRI demonstrated patency in one bypass for which selective catheterism was not possible. The sensitivity of MRI for the diagnosis of patency in aorto-coronary bypasses was 89% with a 92% specificity. MRI did not identify 1 out of 4 bypass stenoses. CONCLUSION: We conclude that the ultrarapid breath-hold magnetic resonance sequences can be used to determine patency of aorto-coronary bypasses with good sensitivity and specificity. Our results would suggest however that this method is inadequate for the diagnosis of bypass stenosis.

Aged↗
PubMed1994

[Favorable outcome of severe right cardiac insufficiency after bipulmonary transplantation].

The authors report a long term success of bipulmonary transplantation in a 15 year old girl with cystic fibrosis and respiratory failure complicated by severe right heart failure. The operation did not cause any particular problems. After transplantation, the clinical signs of right ventricular failure and echocardiographic right ventricular dilatation regressed in less than one week. The right ventricular hypertrophy also regressed. Echocardiography shows no abnormality after 5 years' follow-up.

Adolescent↗
PubMed1994

Measurement of red-cell and plasma volumes.

The different methods of measurement of red blood cell and plasma volumes are exposed. The "Gold Standard" remains the measurement of whole blood volume with 51 chromium labelled red cells and the calculation of red blood cell and plasma volumes with the result of microhematocrit. In some cases, the direct measurement of plasma volume is performed with 125 I-human serum albumin. The mode of expression of the experimental results of blood volume is discussed. Two main modes are employed: expression as a function of the body weight (ml/kg) or as a percent of the value of a normal subject (same age and body area). The usefulness of measurement of red cell and plasma volumes in the diagnosis of true and apparent polycythemia is discussed.

Blood Volume↗
PubMed1993

[Left ventricular involvement in mucoviscidosis after 2 years of age].

BACKGROUND: The cardiac involvement in cystic fibrosis includes the rare cardiomyopathy seen in infants and changes in left ventricular performance in older children. POPULATION AND METHODS: 67 patients, 6 to 34 months-old (mean: 16.7), 37 male and 30 female, with cystic fibrosis, were studied. Their Shwachman score was < 70. None showed any clinical manifestations of left ventricular insufficiency, but 6 patients had right ventricular insufficiency. Echocardiography was performed on 58 patients; it showed dilation of the right ventricle in 32 of them. Left ventricular perfusion was studied with thallium 201 tomoscintigraphy and left ventricular ejection fraction with 99mTc ventriculography. RESULTS: The left ventricular ejection fraction was < 45% in 17 patients and scintigraphy showed hypofixation in 6 of them. In contrast, only 4 of the 50 patients with left ventricular ejection fraction > 45% had thallium hypofixation. CONCLUSIONS: Resting perfusion abnormalities are more frequent in patients with a low left ventricular ejection fraction. These perfusion abnormalities suggest that myocardial fibrosis complicates the advanced stages of cystic fibrosis.

Adult↗
PubMed1993

[Prognostic value of thallium-201 myocardial scintigraphy in patients with hypertension, suspected of coronary disease].

This study was undertaken to determine the prognostic value of exercise myocardial scintigraphy in hypertension patients suspected of coronary disease. One hundred and thirty six hypertension patients (mean age: 59) suspected of coronary disease were monitored for 46 months after thallium 201 exercise myocardial scintigraphy (tomographic mode). Prognostic factors analysed were clinical (typical nature of pain, exercise blood pressure), electrocardiographic (presence of repolarisation abnormalities in resting ECG), ergometric (electrically positive test) and scintigraphic (existence or not of transitory hypofixation). Events sought were: death of coronary origin, non-fatal myocardial infarction, aorto-coronary bypass and coronary angioplasty. One-way analysis showed that the existence of transitory hypofixation by scintigraphy, positive exercise electrocardiogram and typical angina pain enabled the prediction of coronary events. Thus 14 of 36 patients (39%) with transitory or combined hypofixation had a coronary event as against 7 of the 100 patients without transitory hypofixation. Only the existence of transitory hypofixation retained a prognostic value for coronary events by multivariate analysis (relative risk = 5.4, p = 0.001). It was also found that the prognosis was good when scintigraphy did not reveal transitory hypofixation while exercise testing was positive (2 coronary events/27 patients). It is concluded that, despite the possibility of "false positives", linked in particular to myocardial hypertrophy, myocardial scintigraphy offers better prediction of coronary events in hypertension patients that other clinical or electrocardiographic parameters.

Adult↗
PubMed1991

[Study of early myocardial infarction by nuclear magnetic resonance imaging with gadolinium Dota injection].

Ten patients with acute myocardial infarction were studied by magnetic resonance imaging (MRI) with injection of a paramagnetic contrast agent: Gadolinium-DOTA (Gd-DOTA). The time interval between the onset of symptoms and MRI was 8 to 12 days. The site of infarction was determined in all cases by Thallium 201 scintigraphy (hypofixation) and selective ventriculography (segmental wall anomalies): anterior (6 cases), inferior (4 cases). MRI was performed with a 0.5 Tesla CGR Magniscan by the multiple spin technique. A series of tomographic sections was recorded immediately after intravenous injection of 0.4 mmol/Kg of Gd-DOTA. Recent myocardial infarction with parenchymal oedema gives an enhanced transmural signal: only 3 patients had a sufficiently contrasted image on the 1st spin echo. After Gd-DOTA, 7 patients had significantly increased contrast on this echo and in all excellent contrast between infarcted and healthy myocardium was obtained in 9 of the 10 patients. There was excellent correlation concerning the site of infarction between Thallium scintigraphy and left ventriculography. The intensity of signal and T2 relaxation time of different myocardial segments was studied by the regions of interest technique: the ratio of signal intensity of infarcted/healthy myocardium was 1.3 before and 1.7 after Gd-DOTA on first spin echo images. The mean T2 was 54.1 +/- 9 ms in healthy and 82 +/- 28 ms in infarcted myocardium. After Gd-DOTA, both values decreased and tended to equalize.(ABSTRACT TRUNCATED AT 250 WORDS)

Diastole↗
PubMed1991

[Value of magnetic resonance imaging in 2 cases of annular constriction of the ventricles].

Chronic pericarditis can take the form of localised annular bands constricting the atrioventricular grooves, the pulmonary infundibulum and, rarely, the atria. The authors report two cases of pericardial bands surrounding the ventricles and involving the atrioventricular groove resulting in a biloculation of the left ventricle. One case was complicated by adiastole and one by mitral regurgitation due to involvement of the posterior mitral leaflet. Magnetic resonance imaging gave precise definition of these bands and of their extension into the myocardium. This investigation was a valuable complement before surgery of the localised constriction.

Calcinosis↗
PubMed1991

[The value of nuclear magnetic resonance in the study of iron overload in thalassemia patients].

In patients with thalassemia treated by long-term chronic blood transfusions who survive beyond the first ten or twenty years of life but received no or inadequate chelating therapy during the first years, evaluation of iron overload and its consequences on tissues may prove an arduous task. MRI is a non-invasive means of measuring the amount of iron in the liver and the consequences of the iron overload on the heart and other tissues. For this purpose, MRI is more satisfactory than CT scan studies. In this investigation, 20 patients with thalassemia major underwent MRI. Multiple spin echos were used to allow determination of the transversal relaxation constant T2. This constant, expressed in ms, is related to the concentration of iron in the liver as in the following expression: (C) = 5 410/T2-110. MRI studies disclosed a discrepancy between the severity of hepatic hemosiderosis and development of decompensated iron overload cardiomyopathy. In a unique case, in which a heart transplant and two MRI studies were performed, the severe iron overload that failed to respond to several years of subcutaneous chelating therapy was more than halved by intensive intravenous chelation through a central catheter. MRI studies of the heart provide valuable morphologic and functional data. Although the amount of iron in the myocardium cannot as yet be quantified, modifications of the transversal relaxation time provide information on the severity of the overload and the presence of other myocardial alterations.

Adolescent↗
PubMed1990

[Diagnostic approach in coronary disease in vascular surgery. Role of myocardial scintigraphy].

Dipyridamole thallium scintigraphy (tomo SMTD) (fig. 2) and a bicycle stress-testing ECG were performed in a prospective study of 102 patients (Tabl. VIII) referred for aortic reconstruction surgery with aortic cross-clamping (fig. 1), carried out without knowledge of tomo SMTD results. A clinical coronary artery disease (CAD) was suspected in 45 patients (44%). The exercise test (tabl. IV) was inadequate in 78%, normal in 11% and abnormal in 11% of patients. Tomo SMTD (tabl. VI et X) was normal in 60 patients (59%), abnormal with persistent defect in 21 (20.5%) and abnormal with transient defect in 21 (20.5%). Post-operative cardiac events (tabl. I) occurred in 4 patients (3.9%): 2 deaths, 1 non-fatal myocardial infarction and 1 rest angina; but only 2 of these had documented CAD. All 4 had abnormal tomo SMTD (3 with transient, 1 with persistent defect). It is concludes that abnormal tomo SMTD had a significant pronostic value (p less than 0.03) in predicting post-perative cardiac events (tabl. XI, fig. 3) after abdominal aortic surgery with cross-clamping. This test facilitates selection of patients for coronary angiography.

Aged↗
PubMed1989

Lingual osteoma.

The 29th patient with a lingual osteoma is presented. This is the first case, to our knowledge, with preoperative radiographic and computed tomographic documentation. This rare, benign tumor almost always occurs as a pedunculated solitary mass that arises from the posterior tongue near the foramen cecum. The patients are usually young women who complain wf dysphagia or fullness in the base of the tongue. The imaging findings and theories of the origin of this tumor are described.

Adult↗
PubMed1989

Atypical mycobacterial keratitis.

A case of marginal corneal abscess and hypopyon due to Mycobacterium chelonae is presented. Its therapy is described, followed by a brief discussion of atypical mycobacterial keratitis.

Abscess↗
PubMed1989

Microbial investigations in keratitis at the Sydney Eye Hospital.

We investigated 107 cases of presumed microbial keratitis amongst patients presenting to the Sydney Eye Hospital between October 1986 and August 1988 to determine the frequency of infection, the common causative organisms and those factors that predispose to corneal infection. We found that 95% of culture-proven cases were caused by bacteria and that Staphylococcus epidermidis and Corynebacterium sp. accounted for 42.5% of these cases. All bacteria (except Staphylococcus epidermidis and Mycobacterium chelonae) were sensitive to gentamicin. In 62.6% of cases, cultures for bacteria and fungi were negative. Retrospective review of the clinical records of these patients showed that herpes simplex virus, contact lens wear, staphylococcal marginal keratitis and recurrent erosion were important causes of keratitis in this group.

Adolescent↗
PubMed1989

Complications following rhinotomy. Review of 148 patients.

For the period 1974 to 1988, 148 patients undergoing 162 rhinotomies at The Mount Sinai Medical Center, New York, for a variety of benign and malignant neoplasms were reviewed with particular attention to postoperative complications. The effects of certain predisposing factors such as prior rhinotomy, lateral versus total rhinotomy, additional medial maxillectomy or craniofacial resection, and preoperative irradiation or nasal bone erosion are discussed. In addition, a surgical technique of rhinotomy with medial maxillectomy is presented that includes maneuvers designed to prevent these complications.

Female↗
PubMed1989

Inverted papilloma: an analysis of 87 cases.

A group of 87 patients with inverted papilloma, a locally aggressive benign sinonasal tumor, were treated over the past 15 years. Selection of therapy depends on an accurate radiographic assessment of the extent of tumor. The tumor's local aggressiveness, high rate of recurrence, associated malignancy, and multicentric tendency have led most workers to advocate radical surgical removal of the tumor by lateral rhinotomy and en bloc resection of the ethmoid labyrinth. Radiographic evaluation by computed tomography scanning and magnetic resonance imaging permits identification of a small group of patients who have limited lesions and may be candidates for conservative tumor resection by intranasal or transantral sphenoethmoidectomy. Among our ten patients treated with conservative surgery, there was recurrence in one case (10%). Seventy-five patients underwent rhinotomy and medial maxillectomy, with seven cases recurring (9%). The overall recurrence rate was 9% (8 of 87). Among the 87 cases, 5 patients had carcinoma (6%). The literature is reviewed and the principles of case selection and management are discussed.

Adolescent↗
PubMed1989

[Diagnostic value of exercise tomoscintigraphy with thallium 201 in patients with complete left branch block].

Eighteen patients with rate-dependent (n = 5) or chronic (n = 13) left bundle branch block underwent thallium 201 exercise SPECT and selective coronary arteriography. 15 patients showed significant septal or anteroseptal perfusion defects on the exercise scintigrams, but in only 4 of them did the coronary disease involve the left anterior descending artery (LAD) (n = 3) or the left main coronary artery (n = 1). Among patients with normal scintigrams, one had right coronary artery stenosis. Test performance in detecting individual coronary artery stenosis greater than 70 p. 100 was: sensitivity 80 p. 100 (4/5) and specificity 15 p. 100. In patients with left bundle branch block, T1 201 SPECT was indeterminate for LAD disease due to reversible septal perfusion defect. We conclude that the usefulness of stress thallium 201 SPECT in patients with left bundle branch block is very limited.

Aged↗