Abstract
Background: By comparing the different ultrasonographic manifestations in exudate and transudate, we intend to explore the value of ultrasound in auxiliary diagnosis of pleural effusion.Methods: The ultrasonic image features, including echo, separation, light spot, pleural thickness, of 275 exudative pleural effusion (EPE) cases and 307 transudate pleural effusion (TPE) cases confirmed by laboratory examination were retrospectively analyzed.Results: In 275 cases of EPE, the main primary diseases were pneumonia and tuberculous exudative pleurisy, the majority was unilateral (214 cases, 77.8%). Ultrasound showed 47.6% cases had septum, 58.5% cases had echo and those pleural thickness more than 3mm cases accounted for 39.6%. By contrast, in 307 patients with TPE, the major diseases were heart failure, cirrhosis and nephrotic syndrome. Most of the pleural effusions were bilateral, accounting for 97.1%. Ultrasound displayed echo in 3 cases (1.0%), separation in 8 cases (2.6%), light spot in 9 cases (2.9%), and pleural thickening (> 3mm) in 6 cases (2.0%). These positive findings in TPE were statistically less than its counterpart (P < 0.05). Conclusion: Ultrasound is valuable for auxiliary diagnosis of pleural effusion. Some sonographic features of pleural effusion, like echo, septum and pleural thickening, may indicate a high possibility of EPE.