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J Rosso

Publications and source records attributed to J Rosso.

35 records · Page 2Linked to original sources

Acute pulmonary embolism: diagnostic value of digital subtraction angiography.

Digital subtraction angiography (DSA) performed via a peripheral vein was compared prospectively with selective conventional pulmonary angiography (CPA) in 54 patients suspected of having pulmonary embolism (PE). All patients also underwent ascending venography. In contrast to the conventional pulmonary angiograms, all of which were considered satisfactory, 13 of 54 digital subtraction angiograms (24%) were technically unsatisfactory. The interpretable digital subtraction angiograms had 81% sensitivity and 64% specificity. With DSA, one cannot exclude the diagnosis of PE on the basis of normal angiograms (27% false-positive results) as one can with perfusion scanning. On the other hand, DSA showed good sensitivity (94%) in medium to major PE. Therefore it may be the technique of choice in the screening of life-threatening PE for which curative emergency treatment with thrombolytic agents or embolectomy is often necessary.

Acute Disease↗

[Calculation of the ventilation-perfusion ratio in the scintigraphic diagnosis of pulmonary embolism].

Ventilation perfusion scanning fails to diagnose pulmonary embolism in matched defects. In 61 patients (19 with pulmonary embolism proved by angiography, 32 with chronic obstructive lung disease and 10 with acute bacterial pneumonia) we computed the ventilation perfusion ratio (V/Q) in these matched defects, using Krypton 81 m. This analysis demonstrated that the diagnosis of pulmonary embolism could be made with a specificity of 100% when the V/Q ratio was greater than 1.2 in the matched defects. Pulmonary embolism was characterized by a perfusion defect with a high V/Q ratio, even in Laennec infarction. In contrast, the analysis excluded the diagnosis of pulmonary embolism and suggested another disease when the V/Q was less than 0.95 with a specificity of 95%. Perfusion defects in acute pneumonia always had a V/Q less than 1. The diagnosis remained difficult in chronic obstructive lung disease when pulmonary embolism was suspected on subsegmental defects. Nevertheless this could be solved in about 50% of the cases by quantitative analysis. We feel, therefore, that ventilation perfusion scanning should be quantified by V/Q analysis to improve the diagnosis of pulmonary embolism.

Adult↗

Technetium-99m DTPA aerosol and gallium scanning in acquired immune deficiency syndrome.

In 11 non-smoking AIDS patients suspected of pneumocystis carinii pneumonia (PCP), the results of Tc-99m DTPA aerosol clearances, gallium scans, and arterial blood gases were compared with those of bronchoalveolar lavage (BAL). Nine patients had PCP. All had increased clearances five times higher than the normal (5.6 +/- 2.3% X min-1 vs 1.1 +/- 0.34% X min-1, N = 10, P less than 0.001), suggesting an increased alveolar permeability. Gallium scans were abnormal in six patients but normal or slightly abnormal in the three others. Four of these nine patients had normal chest x-rays. In two of these the gallium scan was abnormal, but in the two others, only the increased Tc-99m DTPA clearances showed evidence of lung disease. Two patients had normal BAL, with normal clearances and gallium scans. Four out of the nine patients with PCP were studied after treatment. Three recovered and had normal clearance and gallium scans. One still had PCP with increased clearance but normal gallium scan. Gallium scanning and Tc-99m DTPA clearance are useful for detecting lung disease in AIDS patients with suspected PCP and for prompting BAL when chest x-rays and PaO2 levels are normal. Due to its high sensitivity, a normal Tc-99m DTPA clearance could avoid BAL.

Acquired Immunodeficiency Syndrome↗

Recurrence of pulmonary embolism during anticoagulant treatment: a prospective study.

The risk of early recurrence of pulmonary embolism in patients with venous thromboembolic disease treated by anticoagulants is not well established. To determine the risk linked to contemporary proximal deep venous thrombosis, a prospective study was organised to give clinical and scintigraphic surveillance to 50 patients with angiographically proved pulmonary embolism plus phlebographically proved proximal deep vein thrombosis during the first 15 days of anticoagulant treatment. Perfusion lung scans were performed initially and on days 3, 7, and 15. Only two patients had a recurrence of pulmonary embolism during this period; both episodes were revealed by new symptoms, and one recurrence was fatal. The systematic performance of angiography in four patients found to have new scintigraphic defects led to the diagnosis of "spurious scintigraphic recurrence" in three of them. It is concluded that (a) adjusted anticoagulant treatment showed an effectiveness of 96% for preventing early recurrence of pulmonary embolism in this group of supposed high risk patients, and (b) in patients with recent pulmonary embolism new defects on systematic perfusion lung scans are not specific indicators of recurrent pulmonary embolism.

Adult↗

Lung epithelial permeability to aerosolized solutes: relation to position.

The lung epithelial permeability to inhaled solutes is primarily attributed to the degree of distension of the interepithelial junctions and thus of the alveolar volume. To assess this hypothesis, a submicronic aerosol of technetium-99m-labeled diethylenetriamine pentaacetate (99mTc-DTPA) was inhaled by eight normal subjects in left lateral decubitus (LLD). The regional lung clearance of 99mTc-DTPA was measured in LLD, then in right lateral decubitus (RLD) to reverse the relative distension of the alveoli. Although in LLD the deposition of the aerosol is the greatest in the gravity-dependent regions of the left lung, their 99mTc-DTPA clearances are significantly lower than those of the nondependent regions of the right lung (0.7 +/- 0.3 vs. 2 +/- 0.8%/min, P less than 0.001). In RLD, these regions placed in opposite positions significantly reversed their clearances (1.6 +/- 0.8 vs. 0.6 +/- 0.2%/min, P less than 0.001). Results indicate in lateral decubitus a gravity gradient of 99mTc-DTPA clearances independent of the aerosol deposition. This gradient of epithelial permeability to solutes appears to be influenced by the gradient of alveolar volume.

Adult↗

Validity of self-report measures of girls' pubertal status.

To understand the meaning of somatic changes to the adolescent and their possible effects on behavior, developmentalists have begun to examine maturational timing and status in detail. Efforts have been hampered by the necessity of obtaining somatic growth data by physician examination. In the present study, 3 self-report methods for rating secondary sexual characteristic growth were compared to physician ratings; the accuracy of self-reported height and weight also was assessed. Specifically, 151 11-, 12-, and 13-year-old girls rated their breast and pubic hair development using schematics of the 5 Tanner stages and filled out the Pubertal Development Scale (PDS); their mothers also rated their daughters' development using the Tanner stage schematics. The correlation with physician Tanner ratings was .82 for self-ratings, .85 for ratings by the mother, and between .61 and .67 for self-reports on the PDS. The correlations for self- and actual reports of weight and height were .98 and .75, respectively. The usefulness of the PDS, Tanner ratings, and self-reported height and weight as adequate estimates of pubertal development is discussed.

Adolescent↗

Exercise increases the lung clearance of inhaled technetium-99m DTPA.

The regional lung clearance of a deposited aerosol of [99mTc] diethylenetriaminepentaacetic acid was successively computed at rest and at exercise in seven nonsmoking volunteers in upright posture. The subjects were seated on a bicycle with their backs against a gamma camera. At rest there was a gradient of clearance from the apex to the base of the lung, the apical clearance being significantly higher. At exercise this regional gradient was enhanced by a large and significant increase of the apical clearances (3.40 +/- 0.63% min-1 s.d. compared with 1.82 +/- 0.75% min-1 s.d. at rest, n = 7, p less than 0.01). By contrast the changes of the basal clearances were slight and unsignificant (1.46 +/- 0.71% min-1 s.d. compared with 1.40 +/- 0.82% min-1 s.d.). This increase of the apical lung clearance could be attributed primarily to the increase of apical blood flow induced by exercise and to the subsequent increase of the permeability surface area product.

Adult↗

[Continuous treatment of asthma. Modalities, indications, monitoring].

Long-term treatment must be considered in cases of chronic asthma. Its main purpose is to suppress or decrease the frequency of acute dyspneic episodes; however, it may be more difficult to improve the bronchial obstruction of the patients. In allergic broncho-pulmonary aspergillosis, the treatment aims to prevent irreversible bronchiectasis. The methods and surveillance of long-term treatment are discussed.

Asthma↗

[Physiopathology of chronic bronchitis].

The physiopathology of chronic bronchitis consists of sequential reactions which progressively result in respiratory failure, blood gas abnormalities and finally, post-hypoxia cor pulmonale. Airway obstruction produces maldistribution of inspired gas and starts off a series of compensatory mechanisms with increased resting lung volume and prolonged expiration time resulting in diminution of tidal volume. Abnormal ventilation/perfusion ratios result in shunt and dead space effects, determine blood gas disorders and hypoxia due to reflex vasoconstriction and ultimately lead to pulmonary arterial hypertension with elevated cardiac output and increased vascular resistances. These physiopathological chain-mechanisms account for the clinical symptoms observed, including dyspnoea, episodes of acute bronchitis and in the end, signs of chronic cor pulmonale. They also indicate that the primary objective of treatment is to correct hypoxaemia. This can be achieved by continuous low flow rate oxygen therapy, by drugs capable of redistributing more evenly the ventilation/perfusion ratios and, accessorily, by respiratory analeptic agents. As regards the treatment of pulmonary arterial hypertension, one must admit that many uncertainties are still surrounding the use of vasodilators.

Bronchitis↗

Assessment of ejection fraction with Tl-201 gated SPECT in myocardial infarction: Precision in a rest-redistribution study and accuracy versus planar angiography.

BACKGROUND: Viability and left ventricular ejection fraction (LVEF) are essential measures for the assessment of myocardial infarction (MI). These 2 variables may be evaluated simultaneously by means of thallium-201 gated single photon emission computed tomography (SPECT); however, the precision and accuracy of LVEF measurements with this isotope remain controversial, particularly in cases of extended perfusion defects and poor count densities. METHODS AND RESULTS: Fifty patients with a history of MI underwent a 20-minute rest and a 4-hour redistribution Tl-201 gated SPECT viability protocol, immediately followed by a technetium-99m planar equilibrium radionuclide angiography (ERNA). On gated SPECT images, various count statistics were calculated, and perfusion was automatically quantified by means of CardioMatch, which provided both the size and severity of MI defects. Rest and redistribution LVEFs were determined from gated SPECT with Germano's algorithm, whereas LVEFs were calculated from ERNA using the manufacturer's software. Mean LVEF values calculated with rest gated SPECT, redistribution gated SPECT, and planar ERNA were 30% +/- 13%, 30% +/- 13% and 33% +/- 13%, respectively. Significant differences between repeated gated SPECT LVEFs were not shown by means of the paired t test. Correlation coefficients were high between 20-minute and 4-hour scans (r = 0.89) and between gated SPECT and ERNA (r = 0.88 and r = 0.92 at 20 minutes and 4 hours, respectively). Additionally, close agreement between gated SPECT and ERNA was shown by means of the Bland-Altman plot, despite an underestimation of 3 units. Finally, neither the technical conditions (count density, heart rate, lung uptake, etc) nor the perfusion alteration (size, severity, redistribution) appeared to interfere with the precision and accuracy of gated SPECT LVEF measurement. CONCLUSION: Tl-201 gated SPECT is a precise method for assessing LVEF within the same patient at 4-hour intervals, even with a substantial count decay, and it gives accurate results compared with planar ERNA, even in the case of large perfusion defects.

Adult↗

Right atrial myxoma: an unusual cause of intracardiac right-to-left shunt.

A case of a right-to-left intracardiac shunt caused by a right atrial myxoma is reported. Sudden hypoxaemia was the unique symptom. Measurement of Pao2 while the patient breathed pure oxygen demonstrated the presence of a shunt. Right heart catheterization showed a patent foramen ovale and a pressure gradient between the right atrium and the right ventricle, and between the right and the left atria, explaining the shunt. Cineangiography demonstrated a right atrial myxoma, which was surgically removed. This case report illustrates how a step-by-step diagnostic procedure, based on pathophysiology, may lead to such unexpected findings.

Adult↗