Abstract No. 423 Ultra-low–dose radiation protocol for CT-guided lung biopsies: initial experience

PurposeCT-guided percutaneous needle biopsy (PNB) is an established and effective procedure for tissue diagnosis in suspected pathologic processes. Computed tomography (CT) scans are a significant source of radiation to both patients and staff. A retrospective analysis of ultra-lower–dose (ULD) CT-guided PNB for lung lesions was undertaken to determine safety, efficacy, and complication rates following biopsy.Materials and MethodsThe use of ULD protocol for CT-guided lung biopsy was initiated as part of a quality initiative. The standard dose (120kV localizing/120kV subsequent guiding scans with auto-mA) was changed to a ULD protocol (100kV, 7.5mAs). The total dose and complications of the procedure were tabulated. The technical success rate in obtaining a representative sample for diagnosis was evaluated. The rates of complication were compared to the 2010 guidelines published in a joint document by the American College of Radiology and the Society of Interventional Radiology.ResultsA total of 52 consecutive patients (27 males and 25 females; average age 71) who underwent lung lesion biopsies were evaluated. The average size of lesion was 4.1cm. The overall biopsy success rate was 100%. The rate of pneumothorax was 19%, well within suggested guidelines of 12-45%. Pneumothoraces requiring tube insertion occurred in 6% of cases, compared to guidelines of 2-15%. There is a strong inverse correlation between the size of the lesion (≤3 cm; >3 cm) and the rate of complications (p = .00020). Nonetheless, the size of the lesion did not influence the total dose of radiation required for the biopsy procedure (p = .48).ConclusionRadiation dose to the chest during CT-guided lung PNB is reduced significantly through the use of a ULD protocol. Our findings suggest that reducing the CT radiation dose does not negatively impact patient safety or biopsy diagnostic rates in PNB.