THE ALGORITHM OF IMAGING DIAGNOSTICS OF P ULMONARY-EMBOLISM - TIME FOR A NEW DEFINITION

Acute pulmonary embolism (PE) is an increasing and underdiagnosed caus e of mortality and morbidity in hospitalised patients; pulmonary hyper tension based on chronic pulmonary embolism is an uncommon, but severe and surgically curable complication. Since clinical signs might be si lent or unspecific, both acute and chronic PE require imaging methods for diagnosis and treatment planning. Chest radiographic findings are usually non-specific. Scintigraphy provides a high sensitivity for PE, but lacks anatomic resolution and sufficient specificity. Pulmonary a ngiography, albeit accurate, is an invasive procedure associated with low but still not negligible morbidity and mortality. Hence, non-invas ive methods offer advantages. Spiral CT, for example, is most reliable in the diagnosis of acute and chronic PE: Such fast CT techniques pro vide a non-invasive means to detect and differentiate acute emboli and organised thrombi, as well as perfusion abnormalities and other conco mitant findings. MRI offers both morphological and functional informat ion on lung perfusion and right heart function, but its image quality still needs improvement to be comparable with CT. Thus, while MRI must still be tested in clinical studies. CT is recommended as a screening method in acute and chronic pulmonary embolism.