Significant radiation dose reduction in cerebral angiography using a new imaging acquisition and processing platform-a phantom study.

Purpose: The new Philips Allura Clarity upgrade allows Xray reduction during image acquisition by automatic motion compensation, temporal and spatial noise reduction and image enhancement. Our aim was to quantify the radiation dose reduction achieved after installation of the Philips Allura Clarity platform compared to the Philips Allura Xper platform. Method(s): Polymethylmethacrylate (PMMA) phantoms of 4 different thickness (15, 18, 20 and 23 cm) were used to simulate patient head attenuation. A direct dosimeter was used to measure Air Kerma rates (AKR) during fluoroscopy and cerebral digital subtraction angiography (DSA) on the Philips Allura Xper platform, and then again after the Philips Allura Clarity upgrade. The measurements conformed to the International Electrotechnical Commission (IEC) standards i.e. no table top, X-ray beam focus to PMMA entrance distance of 62.5 cm, source to image distance of 105 cm and dosimeter placement at the PMMA entrance. Result(s): The pre and post Philips Allura Clarity upgrade fluoroscopy AKRs for 15, 18, 20 and 23 cm phantoms were 0.09 to 0.08, 0.15 to 0.12, 0.20 to 0.19, 0.32 to 0.23 mGy/s respectively. Mean dose reduction was 17% (range 9-30%). In DSA the pre and post upgrade AKRs for 15, 18, 20 and 23 cm phantoms were 3.08 to 0.23, 6.04 to 0.58, 9.57 to 0.89, 14.68 to 1.74 mGy/frame respectively. Mean dose reduction was 90% (range 88-92%). Conclusion(s): This study confirms significant radiation dose reduction, particularly during DSA, after installation of the Philips AlluraClarity imaging platform.