Prospective validation of the stripe sign in ventilation-perfusion scintigraphy.

Overview

The data base of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) was used to test the accuracy of the stripe sign for the exclusion of embolic perfusion defects on lung scintigrams. Lung scan readings showed the presence and location of this sign in 50 (4.7%) of 1,064 patients. Perfusion defects showing the stripe sign were not associated with pulmonary embolism in the same lung zone (upper, middle, or lower third of each lung) in 93% (79 of 85) of instances. Thirty-eight percent (n = 32) of lung zones with the stripe sign had associated chest radiographic abnormalities, and 69% (n = 59) had ventilation scan abnormalities. Formulation of the scan diagnosis according to PIOPED criteria showed fewer indeterminate readings in patients with the stripe sign and without pulmonary embolism when the stripe sign was used. Use of the sign changed diagnosis in less than 1% of the total population, however, because of its low overall prevalence. The stripe sign is a useful adjunct to standard criteria in the interpretation of pulmonary scintigrams for evaluation of suspected acute pulmonary embolism.