John Miras Racadio MD, Presenter: Research collaboration, Koninklijke Philips Electronics NV Speaker, Koninklijke Philips Electronics NV Medical Advisory Board, Koninklijke Philips Electronics NV

Terry T. Yoshizumi PhD, Abstract Co-Author: Research support, General Electric Company

Greta Toncheva BS, Abstract Co-Author: Nothing to Disclose

Dick Stueve, Abstract Co-Author: Manager, Koninklijke Philips Electronics NV

Colin Anderson-Evans BS, Abstract Co-Author: Nothing to Disclose

Donald P. Frush MD, Abstract Co-Author: Research funded, General Electric Company

New technology coupling flat-detectors with cone-beam CT within an angiography-interventional C-arm allows for 3D image acquisition and real time fluoroscopy to be performed in a single room, potentially obviating traditional CT guidance.  This study compared effective dose (ED) of pediatric cone-beam CT in an angio-interventional C-arm to MDCT.

Dosimetry evaluation was performed using a mobile MOSFET wireless dosimetry system (Best Medical); 20 high sensitivity MOSFET dosimeters were placed in a 5 year old anthropomorphic phantom (CIRS) to calculate ED (ICRP 60). Cone-beam CT (“XperCT” from FD20, Philips Medical) was performed in the following clinically available modes: Cerebral High Dose, Cerebral Low Dose, and Abdomen Low Dose. MDCT (64 Aquilion, Toshiba Medical) was performed in the following clinically available modes using institutional weight-based scan parameters: Cerebral with fixed mA, Abdominal with fixed mA, and Abdominal with modulated mA.

EDs of cone-beam CT in Cerebral High Dose and Cerebral Low Dose modes were 4.42mSv and 2.21mSv respectively, and in Abdomen Low Dose mode was 0.98mSv. ED of MDCT in Cerebral with fixed mA mode was 8.66mSV. EDs of MDCT in Abdomen with fixed mA and Abdomen with modulated mA modes were 9.39mSv and 6.75mSv respectively. ED of an abdominal cone-beam CT was therefore 10-15% of an abdominal MDCT, and ED of a cerebral cone-beam CT was 26-51% of a cerebral MDCT. For Cerebral High Dose cone-beam CT, ED for 100% FOV was 4.42mSV vs 1.80mSv for 25% FOV. For Abdominal Low Dose cone-beam CT, ED for 100% FOV was 0.98mSv vs 0.26mSv for 25% FOV. For cone-beam CT, dose to organs distant from the FOV was minimal; organ dose to breast was 0.010cGy during Abdominal Low Dose and 0.08cGy during Cerebral High Dose.

The ED for cone-beam CT can be as little as 10-15% of the ED of contemporary (64-slice) MDCT, and may provide for efficient combined diagnostic and interventional opportunities with marked dose reductions. Dose savings with reduction in FOV can be substantial. MOSFET technology will allow similar comparisons to be performed on different C-arm cone-beam CT and MDCT systems since image acquisition parameters may differ.

ED for C-arm cone-beam CT is a fraction of that of contemporary MDCT, and may provide for efficient combined diagnostic and interventional opportunities with marked dose reductions.

Racadio, J, Yoshizumi, T, Toncheva, G, Stueve, D, Anderson-Evans, C, Frush, D, Radiation Dosimetry Evaluation of C-arm Cone-Beam CT for Pediatric Interventional Radiology Procedures: A Comparison with MDCT.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6014382.html