Measurement of pulsatile flows and variable volumes by bolus injection of indicator in a model of the pulmonary circulation.

The reliability and accuracy of the bolus injection-dye dilution technique were assessed for a physiological range of frequencies (13-49 min-1) and stroke volumes (60-160 ml) on a glass model where flows and volumes varied as a preset function of time (n = 320). We found that the technique overestimates flow by about 8% with a 95% confidence interval of +/- 10% for one measurement. Mean transit times are accurate within a +/- 7% confidence interval for one measurement.

[Isotopic scintigraphy in the diagnosis of the spread of bronchial cancer].

Ventilation of the lungs using Xenon 133 and perfusion scans using 99m Tc albumin particles in microspheres were performed on 455 patients with bronchial cancers and 55 patients with pulmonary metastases. Ventilation-perfusion mismatch and functional defects of the lung, which are never found in nodular-shaped pulmonary metastases, vary in frequency according to the anatomo-pathological type of the tumor and constitute a limiting factor for ablation.