Abstract

Lung scan appearances thought to be characteristic of emphysema are described. Three criteria are stated and 44 scans showing all these criteria were selected from 154 lung scans done during a 10-month period: in fact the scans of all the patients (seen in the Clinical Physiology Department during the 10 months) who were thought on clinical grounds to have emphysema had been selected. Three scans were of patients with fibrosing alveolitis with no evidence of airways obstruction and they were easily identified from the chest radiograph. In six patients the diagnosis of emphysema is reasonable but unproved. Three patients show no real evidence of emphysema. Firstly, all the 154 lung scans were done using technetium-99m as the source of γ-radiation, whereas most authors have used iodine-131; secondly, the scanner setting was the same for all the scans, with a minimum γ-radiation intensity of 30,000 counts/min being necessary to produce an adequate scan. The results of this investigation suggest that there is a scan appearance characteristic of emphysema as long as the patient shows other evidence of airways obstruction.