Direct Organ Dose Measurements in Cadaveric Subjects to Investigate Dose Reduction Provided by Iterative Image Reconstruction Techniques
A Mench1*, L Sinclair1, T Griglock2, B Cormack1, S Bidari1, M Arreola1, (1) University of Florida, Gainesville, FL, (2) Oregon Health & Science Univ, Portland, ORSU-E-I-44 Sunday 3:00PM - 6:00PM Room: Exhibit Hall
Purpose: To quantify average organ dose reduction resulting from use of adaptive iterative image reconstruction algorithm in Computed Tomography (CT).
Methods: To determine the average organ dose reduction offered by the Adaptive Iterative Dose Reduction algorithm (AIDR3D) on a Toshiba Aquilion One 320-slice CT scanner, organ doses were directly measured utilizing a method involving cadaveric subjects and optically-stimulated luminescent dosimeters (OSLDs). Three female cadaveric subjects of various body habitus were scanned for the case of a clinically standardized Chest Abdomen Pelvis (CAP) protocol. Average organ doses were measured using OSLDs inserted into the breasts, lungs, liver, stomach, small intestine, colon, ovary, and uterus and placed on the skin of the cadavers. Measurements were first obtained for a standard non-contrast CAP exam and then again, under identical scanning conditions, with the AIDR3D turned on. Measured doses were compared between the two scans for each of the organs.
Results: Average organ dose reduction ranged from as low as 4% to as high as 66% for various organs. When averaged across all organs, the overall percent reduction amongst the three cadaveric subjects ranged from 18% to 46%. Significant dose reduction was noted for the lungs, breast and uterus in all three cadaveric subjects. The cadaveric subject with the lowest BMI level experienced the most prominent reduction in organ doses when compared to the subjects of higher BMI.
Conclusions: As CT continues to be an indispensable tool in diagnostic radiology, future technological developments will remain focused on dose reduction methods. From this work it is clear that use of the AIDR 3D image reconstruction algorithm offers significant organ dose savings to patients. Based on recent literature and our own clinical experience, the dose savings do not come at the cost of degraded image quality.