Differences in Radiation Exposure of CT-Guided Percutaneous Manual and Powered Drill Bone Biopsy

PURPOSE: Apart from the commonly applied manual needle biopsy, CT-guided percutaneous biopsies of bone lesions can be performed with battery-powered drill biopsy systems. Due to assumably different radiation doses and procedural durations, the aim of this study is to examine radiation exposure and establish local diagnostic reference levels (DRLs) of CT-guided bone biopsies of different anatomical regions. METHODS: In this retrospective study, dose data of 187 patients who underwent CT-guided bone biopsy with a manual or powered drill biopsy system performed at one of three different multi-slice CT were analyzed. Between January 2012 and November 2019, a total of 27 femur (A), 74 ilium (B), 27 sacrum (C), 28 thoracic vertebrae (D) and 31 lumbar vertebrae (E) biopsies were included. Radiation exposure was reported for volume-weighted CT dose index (CTDI(vol)) and dose–length product (DLP). RESULTS: CTDI(vol) and DLP of manual versus powered drill biopsy were (median, IQR): A: 56.9(41.4–128.5)/66.7(37.6–76.2)mGy, 410(203–683)/303(128–403)mGy·cm, B: 83.5(62.1–128.5)/59.4(46.2–79.8)mGy, 489(322–472)/400(329–695)mGy·cm, C: 97.5(71.6–149.2)/63.1(49.1–83.7)mGy, 627(496–740)/404(316–515)mGy·cm, D: 67.0(40.3–86.6)/39.7(29.9–89.0)mGy, 392(267–596)/207(166–402)mGy·cm and E: 100.1(66.5–162.6)/62.5(48.0–90.0)mGy, 521(385–619)/315(240–452)mGy·cm. Radiation exposure with powered drill was significantly lower for ilium and sacrum, while procedural duration was not increased for any anatomical location. Local DRLs could be depicted as follows (CTDI(vol)/DLP): A: 91 mGy/522 mGy·cm, B: 90 mGy/530 mGy·cm, C: 116 mGy/740 mGy·cm, D: 87 mGy/578 mGy·cm and E: 115 mGy/546 mGy·cm. The diagnostic yield was 82.4% for manual and 89.4% for powered drill biopsies. CONCLUSION: Use of powered drill bone biopsy systems for CT-guided percutaneous bone biopsies can significantly reduce the radiation burden compared to manual biopsy for specific anatomical locations such as ilium and sacrum and does not increase radiation dose or procedural duration for any of the investigated locations. LEVEL OF EVIDENCE: Level 3.