Maximum inaccuracy of CT number measured in a ROI in a water 0 +/- 4 phantom Maximum deviation of image noise from manufacturer’s 10% 5% specification Maximum deviation of CT number from central value for water 6 HU 4 HU phantom up to 20 cm diameter Maximum spatial resolution deviation from specification measured 10% the manufacturer’s protocol Maximum distance from the centre of the z-axis dose profile to the 2 mm transverse Maximum scan projection radiography (scout mode) deviation from 2 mm specified distance Maximum couch top index deviation from specified distance 2 mm Fluoroscopy and angiography Parameter Requirement Primary Secondary Maximum fluoroscopic entrance surface dose rate at 30 cm from the detector cover: normal mode 50 mGy/min boost mode 100 mGy/min Maximum fluoroscopic image receptor entrance dose rate with 2.5 mm Cu in the X-ray beam at approximately 90 kV: field size < 14 cm 120 µGy/min 14 cm ≤ field size < 23 cm 90 µGy/min size ≥ 23 cm 60 µGy/min Maximum detector entrance dose (DSA): ≤ 10 frames/s 10 µGy/frame > 10 frames/s 1 µGy/frame Maximum detector entrance dose (cinefluorography): size < 17 cm 0.4 µGy/frame 0.2 µGy/frame size ≥ 17 cm 0.2 µGy/frame 0.1 µGy/frame Maximum patient entrance dose – acquisition: DSA 2 mGy/frame cardiac 0.2 mGy/frame Maximum inaccuracy of KAP or indicated patient entrance dose to 35% 20% measured dose
Maximum inaccuracy of CT number measured in a ROI in a water phantom 0 +/- 4 Maximum deviation of image noise from manufacturer’s specification 10% 5% Maximum deviation of CT number from central value for water phantom up to 20 cm diameter 6 HU 4 HU Maximum spatial resolution deviation from specification measured the manufacturer’s protocol 10% Maximum distance from the centre of the z-axis dose profile to the transverse 2 mm Maximum scan projection radiography (scout mode) deviation from specified distance 2 mm Maximum couch top index deviation from specified distance 2 mm Fluoroscopy and angiography Parameter Requirement Primary Secondary Maximum fluoroscopic entrance surface dose rate at 30 cm from the detector cover: normal mode boost mode 50 mGy/min 100 mGy/min Maximum fluoroscopic image receptor entrance dose rate with 2.5 mm Cu in the X-ray beam at approximately 90 kV: field size < 14 cm 14 cm ≤ field size < 23 cm size ≥ 23 cm 120 µGy/min 90 µGy/min 60 µGy/min Maximum detector entrance dose (DSA): ≤ 10 frames/s > 10 frames/s 10 µGy/frame 1 µGy/frame Maximum detector entrance dose (cinefluorography): size < 17 cm size ≥ 17 cm 0.4 µGy/frame 0.2 µGy/frame 0.2 µGy/frame 0.1 µGy/frame Maximum patient entrance dose – acquisition: DSA cardiac 2 mGy/frame 0.2 mGy/frame Maximum inaccuracy of KAP or indicated patient entrance dose to measured dose 35% 20%
code-of-practice-diagnostic-and-interventional-radiology-nov18.docx