Abstract

Background: The Progressive Investigation of Pulmonary Embolism Diagnosis (PIOPED) classifies the results of ventilation perfusion scintigraphy as having a high, intermediate and low diagnostic probability of pulmonary embolism or as normal. This classification can be confusing for the clinician. Aim: To retrospectively review the diagnoses of ventilation perfusion scintigraphies performed at a general hospital. Material and methods: All reports of ventilation perfusion scintigraphies done between 1997 and 2000 at the Nuclear Medicine Service of Valdivia Hospital were retrospectively reviewed. Results: During the study period, 85 patients with suspected pulmonary thromboembolism were referred for a ventilation perfusion scintigraphy and in 70, the procedure was done. Twenty-one (30%) patients were classified as having a high probability of pulmonary thromboembolism, 12 (17%) as having an intermediate probability, 31 (44%) as having a low probability and the scintigraphy was considered normal in 6 (9%) patients. Conclusions: The predictive value of ventilation perfusion scintigraphy must be interpreted using this diagnosis classification.