Multidetector CT fluoroscopy and cone-beam CT-guided percutaneous transthoracic biopsy: comparison based on patient doses.

In this study, two different techniques used for image-guided percutaneous transthoracic needle biopsy have been compared in terms of patient dose: computed tomography (CT) fluoroscopy (performed on a Toshiba Aquilion 64), supplied with several multidetector CT (MDCT), and cone-beam CT (CBCT) (performed on a Philips Allura Xper FD20), supplied with a few C-arm flat-panel angiographic devices. Dose data (10 patients for each technique) have been collected, and organ doses and effective dose have been evaluated using software packages enabling to simulate real acquisition geometry and X-ray exposure. As a result, higher doses were found for MDCT compared with CBCT: the effective dose is 50% higher for MDCT; ratios between mean organ doses range between 1.2 and 1.7, except for breast (0.9) and oesophagus (3.7). Even though the observed differences are not always statistically significant, the general distribution of organ doses confirms that the MDCT-guiding technique delivers higher dose than the CBCT-guided one.