Background: The purpose of this study was to prospectively evaluate the effectiveness of CT-guided transthoracic fine needle aspiration in the diagnosis of pulmonary lesions and to determine the complication rate of this procedure.
Material/Methods: A prospective review was undertaken of 316 patients who underwent CT-guided transthoracic fine needle aspiration performed at our center between October 2000 and April 2001. Twenty- two patients were excluded because no final diagnosis was achieved. The present study included 294 patients. All fine needle aspirations were performed with a 22-gauge aspirating needle under CT guidance.
Results: An accurate diagnosis was made in 228 of 259 malignant lung lesions (88%). A specific diagnosis was obtained in 34.3% of the benign lesions. The sensitivity for malignancy and specificity for benign lesions were 88% and 100%, respectively. Positive and negative predictive values were 100% and 53%, respectively. There was no false-positive diagnosis for malignancy. Sensitivity was 87% for centrally located lesions and 89.3% for peripherally located lesions (p>0.05). Complications included pneumothorax, 24 of 294 cases (8.2%); chest tube, 3 cases (12.5%); minor hemoptysis, 5 cases (1.7%); and pulmonary hemorrhage, 4 cases (1.4%).
Conclusions: Our results suggest that this procedure has high diagnostic accuracy and an acceptable rate of complications.

Keywords: computed tomography, guidance, Diagnosis, transthoracic fine needle aspiration