Percutaneous needle biopsy of mediastinal masses using a computed tomography-guided extrapleural approach.

This study was conducted to determine the reliability of mediastinal biopsy using a computed tomography-guided extrapleural approach. Twenty patients (16 men and 4 women) between the ages of 30 to 79 years underwent 22 percutaneous biopsies. The sampled masses ranged in size from 1.6 to 8 cm. A coaxial 17-gauge needle system was advanced into the fascia subjacent to the parietal pleura. An extrapleural fluid collection was created using a 20%/80% ratio of 1% lidocaine and normal saline. The blunt cannula was then advanced through the fluid to the edge of the lesion, and core or cytologic specimens were obtained. A diagnosis was obtained in 18 of 20 patients (90%). There were 10 malignant and 8 benign diagnoses. Complications included pneumothorax (1), vasovagal reactions (1), intercostal neuritis (1), and transient Homer's syndrome (1). In this series, both a high diagnostic yield as well as a low complication rate were obtained.