Assessment of pulmonary ventilation scans using xenon-127 in the diagnosis of pulmonary embolism.

Pulmonary ventilation scans using 127Xe were compared with scans using 133Xe in the diagnosis of pulmonary embolism. A perfusion scan using 99mTc -microspheres and ventilation scans with each of the xenon isotopes were performed on 44 patients referred for lung scanning to confirm or exclude a suspected clinical diagnosis of pulmonary embolism. No significant difference was found in the frequency of diagnosis of pulmonary embolism when comparing each of the ventilation scans with the corresponding perfusion scan. For reasons discussed, 127Xe may be more useful than 133Xe for pulmonary ventilation scanning.