Application of quantitative contrast-enhanced ultrasound for evaluation and guiding biopsy of peripheral pulmonary...

To evaluate the usefulness of contrast-enhanced ultrasonography (CEUS) in differentiating malignant from benign peripheral pulmonary lesions, and to evaluate the feasibility, accuracy, and utility of CEUS-guided biopsy for peripheral pulmonary lesions.

Thirty-three patients with histopathologically confirmed peripheral pulmonary lesions (22 malignant, 11 benign) were enrolled in this retrospective study. Conventional ultrasound (US) was first performed and then CEUS with a contrast-specific mode and sulfur hexafluoride-filled microbubble contrast agent. CEUS indices-time of enhancement (TE), time to peak (TP), extent of peak (EP), mean transit time (MTT), area under curve (AUC), and slope-were recorded and compared between the groups. The ability of CEUS and US to detect necrotic areas within lesions was also compared and the accuracy of CEUS-guided biopsy was calculated.

On CEUS, TE was significantly shorter in acute pneumonia lesions than in other types of lesions (p=0.03). Other indices were not significantly different between benign and malignant lesions. Detection of necrosis within lesions was significantly higher with CEUS than with US (51.5% versus 27.3%; p=0.04). The accuracy of CEUS-guided biopsy was 96.9% (32/33).

The study findings suggest that CEUS can identify necrotic areas within lesions, and thereby, play a useful role in imaging-guided biopsy. The present pilot study indicates that CEUS may help to identify acute pneumonia lesions from other types of pulmonary lesions. CEUS might be a useful additional technique for the diagnosis of lung lesions.