C-Arm Cone-Beam CT-Guided Percutaneous Transthoracic Lung Biopsy: Usefulness in Evaluation of Small Pulmonary Nodules

OBJECTIVE. The purpose of this study was to evaluate the usefulness of C-arm cone-beam CT-guided percutaneous transthoracic lung biopsy of small (<= 2 cm) lung nodules. MATERIALS AND METHODS. Twenty-seven patients who underwent C-arm cone-beam CT-guided percutaneous transthoracic lung biopsy of small (<= 2 cm) lung nodules were enrolled in the study. The mean nodule size was 13 +/- 4 mm in diameter. These lesions were divided into two groups according to size: 10 lesions 1 cm or smaller and 17 lesions larger than 1 cm. The diagnostic accuracy, sensitivity, and specificity in the two groups were compared by use of Fisher's exact test. Radiation dose in a female humanoid phantom was measured with radiophotoluminescent glass dosimeters. The average patient dose was calculated. RESULTS. Eighteen malignant (67%) and eight benign (30%) nodules and one (3%) indeterminate nodule were found. The overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 94%, 89%, 94%, 89%, and 92%. The sensitivity, specificity, and accuracy were 100%, 75%, and 90% for the lesions 1 cm or smaller and 91%, 100%, and 94% for the lesions larger than 1 cm. The accuracy, sensitivity, and specificity did not differ significantly between the groups (all p > 0.05, Fisher's exact test). The average radiation dose among 27 patients was 4.6 mSv (range, 2.19-9.37). CONCLUSION. C-arm cone-beam CT-guided percutaneous transthoracic lung biopsy is a useful diagnostic technique in the evaluation of small lung nodules.