The effectiveness of tangential fluoroscopic guidance of the anesthetizing needle to avoid transgression of the pleura and therefore lower pneumothorax and chest tube insertion rates after transthoracic needle lung biopsy (TNB) was investigated. Tangential guidance was used in 41 patients (group A) and was not used in 51 (group B). The pneumothorax rate was 39% (16 of 41) for group A and 31% (16 of 51) for group B. The chest tube insertion rate was 12% (five of 41) for group A and 4% (two of 51) for group B. None of the differences in rates were significant. Use of this technique does not lower pneumothorax or chest tube insertion rates in patients undergoing TNB.