sodium-pertechnetate-tc-99m and Pulmonary-Edema

99mTc-Technegas scintigraphy is used to evaluate ventilation abnormalities in patients with pulmonary emphysema. Although abnormalities of ventilation distribution are easy to find, no objective index exits. Evaluation is subjective and differs with each radiologist. Thus, it is difficult to compare cases and the clinical course in the same case. The present study for quantitative evaluation demonstrated an excellent correlations between mean voxel values of the lung and stage classification. Furthermore, a correlation was observed between the mean and FEV1.0%. These findings indicate that the quantitative analysis of SPECT data is useful for classifying clinical stage and comparing cases.

Topics: Humans; Pulmonary Edema; Respiratory Function Tests; Sodium Pertechnetate Tc 99m; Tomography, Emission-Computed, Single-Photon

We have used a combination of transmission and emission gamma camera techniques to scan the thorax in the anteroposterior plane in 21 patients with partially treated cardiogenic pulmonary oedema and have compared their results with those from 20 age-matched normal subjects who were scanned previously. For transmission scanning, an external 99Tcm flood source was used; for emission scanning we labelled sequentially the vascular compartment with 99Tcm autologous erythrocytes and the interstitium with 99Tcm diethylenetriaminepentaacetic acid (99Tcm-DTPA). From the transmission scans we derived the transthoracic tissue thickness (Tt) and from the emission scans, after correction for attenuation, the regional blood and interstitial volumes. In the lower zone of the right lung, mean (S.D.) Tt in normal subjects was 10.9 (S.D. 3.1) cm and in subjects with lung oedema was 12.5 (S.D. 3.1) cm (P = 0.07). There was a weak correlation between Tt and a radiographic numerical score of oedema severity (r = 0.47, P less than 0.05). In eight subjects with lung oedema, lung tissue thickness (T1) was estimated (by subtraction from Tt of radiographically estimated chest wall thickness). The T1 correlated closely with the radiographic score (r = 0.78, P less than 0.01). There was no significant change in blood or interstitial volumes in oedema.. (1) transmission scanning gives an indication of oedema severity if an allowance is made for chest wall thickness; (2) 99Tcm-DTPA fails to equilibrate fully with oedema liquid during an equilibration period of 5 min.

Topics: Adult; Aged; Aged, 80 and over; Erythrocytes; Female; Humans; Male; Middle Aged; Pulmonary Edema; Radionuclide Imaging; Sodium Pertechnetate Tc 99m; Technetium; Technetium Tc 99m Pentetate

We replaced the standard serial bronchoalveolar lavage technique with a new "rewash" lavage procedure to allow estimation of the volume and protein concentration of the epithelial lining fluid (ELF) in anesthetized sheep. A bronchoscope 6.0 mm in diameter wedged in an airway was used to lavage a segment of lung with four cycles of instillation and aspiration of the lavage solution containing a radioactive tracer (technetium pertechnetate, 99mTcO4-). Errors caused by the fall in concentration of the tracer during the lavage were minimized by extrapolating the tracer concentration back to time zero when the lavage solution had mixed with the ELF, but had not had time to be affected by loss of the tracer or influx of fluid from the interstitium. In control sheep, the ELF of these lavaged segments had a mean volume of 1.6 +/- 1.0 ml and a mean protein concentration that was 26 +/- 19% of the protein concentration measured in the plasma. Increasing the left atrial pressure 19 +/- 5 cm H2O to cause "cardiac lung edema" had no significant effect on the ELF volume, but it increased the mean protein concentration to 57 +/- 30% of the plasma value (p less than 0.01). Lung injury caused by intravenous oleic acid caused lung edema, increased the mean ELF volume to 6.8 +/- 2.2 ml, and increased the mean ELF protein concentration to 86 +/- 26% of the plasma value (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Bronchoalveolar Lavage Fluid; Bronchoscopes; Epithelial Cells; Lung; Proteins; Pulmonary Alveoli; Pulmonary Edema; Sheep; Sodium Pertechnetate Tc 99m; Technetium Tc 99m Aggregated Albumin; Therapeutic Irrigation