Tc-99m DTPA aerosol lung scintigraphy in patients requiring mechanical ventilation

Xenon ventilation images are of limited diagnostic value in intubated patients since only posterior views can be readily obtained. In this study, Mallinckrodt Tc-99m DTPA aerosol was evaluated for its ability to provide six ventilation projections comparable to MAA perfusion images. Earlier particles have had the drawback to impacting in either ventilator tubing or the patient's major bronchi, limiting clinical utility. Nine patients were studied. Eight had good aerosol distribution without significant particle impaction. In the remaining patient, decreased aeration and holdup of activity beyond the area of impaction was confirmed by xenon ventilation images. Comparable ventilation and perfusion projections were obtained in every patient studied