Transthoracic Sonography in Comparison to Multislice Computed Tomography in Detection of Peripheral Pulmonary Embolism

The aim of the study was to compare transthoracic sonography (TS) with multislice computed tomography (MSCT) in the detection of peripheral pulmonary embolism (PE). In addition, the study verified peripheral parenchymal findings visualized by TS and MSCT. A total of 33 patients (16 females, 17 males; mean age = 65.4 years) with symptoms of suspected PE were enrolled in the study. TS and MSCT were undertaken within 24 h of the beginning of clinical PE signs. Ten patients suffered from PE as visualized by MSCT. The sensitivity of TS for detecting PE was 70.0% and the specificity was 69.6%. Preferentially, PE and peripheral parenchymal findings were situated in the lower lobes. Oligemia was the main parenchymal alteration detected by MSCT. TS demonstrated that wedge-shaped consolidations were frequently associated with PE. In addition, localized pleural effusion was a typical finding in the presence of PE for both TS and MSCT. TS had moderate sensitivity and specificity compared with MSCT. Furthermore, the study revealed that PE is often associated with peripheral parenchymal changes, both of which are detectable by TS and MSCT. In case of contraindication with MSCT, TS is a potential technique for diagnosing PE-related parenchymal findings and can serve as an alternative method in the diagnosis of PE. However, a negative result with TS does not rule out a PE.