CT-guided Percutaneous Transthoracic Aspiration Biopsy for Pulmonary Lesions:Comparison between Lesion Size and Depth

Objective To evaluate the influence of lesion size and depth on the diagnostic accuracy and the rate of pneumothorax in patients undergone CT-guided transthoracic aspiration biopsy for pulmonary lesions.Methods CT-guided percutaneous transthoracic biopsy was performed in 398 patients that had surgical resection or clinical follow-up.According to lesion size,lesions were divided into≤2 cm,2～4 cm and ≥4 cm.Lesion depth was measured from the pleura surface to the edge of the lesion.This depth was classified in three categories:≤1 cm,1～3 cm and ≥3 cm.Comparison of the diagnostic accuracy and the frequency of pneumothorax in different size and depth of lesion was performed.Results(1)The overall diagnostic accuracy of CT-guided percutaneous needle aspiration biopsy was 83.2%(331/398).Pneumothorax occurred in 58(14.6%)of 398 biopsy;(2)The diagnostic accurate rate in different size of lesion was 73.3%(44/60),81.5%(176/216)and 91.0%(111/122)respectively,χ2=9.91,P0.01.The occurred rate of pneumothorax in different size of lesion was 20%(12/60),16.7%(36/216)and 8.2%(10/122)respectively,χ2=6.16,P0.05;(3)The diagnostic accurate rate in different depth lesion was 83.0%(117/141),85.9%(122/142)and 80.0%(92/115)respectively,χ2=1.59,P0.05.The occurred rate of pneumothorax in different depth lesion was 2.8%(4/141),14.8%(21/142)and 28.7%(33/115),χ2=34.03,P0.01.Conclusion CT-guided biopsy has less accuracy and high occurred rate of pneumothorax in smaller pulmonary lesion than that in larger lesions.The diagnostic accuracy is similar for different depth lesions.The occurred rate of pneumothorax is increased with increasing depth of the lesion.