The accuracy of chest sonography in the diagnosis of small pleural effusion

Abstract

Background. The aim of the study was to evaluate the accuracy of chest sonography in the radiological diagnosis of small pleural effusions.

Patients and methods. Patients referred for abdominal and/or chest sonographies for various reasons were examined for sonographic features of pleural effusion. From January 1997 till January 2000, 69 patients were included into the study. Fifty-two patients were found to have pleural effusion not exceeding 15 mm in depth, the rest of them served as controls. Subsequently erect posteroanterior and expiratory lateral decubitus projections were done in all patients.

Results. Compared to radiological examination chest sonography had a positive predictive value of 92% in the diagnosis of small pleural effusions in our study population. The mean thickness of fluid was 9.2 mm on ultrasonography and 7.6 mm on expiratory lateral decubitus views (P<0.01).

Conclusions. Chest sonography showed a high degree of accuracy for demonstrating small pleural effusions and could replace lateral decubitus chest radiographs adequately.