Impact of operator-selected image noise index and reconstruction slice thickness on patient radiation dose in 64-MDCT.
OBJECTIVE
Our objective was to develop a better understanding of the complex interrelationship between image noise, reconstruction slice thickness, and patient radiation dose on a 64-MDCT scanner that uses automated tube current modulation.


METHODS
We reviewed physics theory and performed phantom dose measurements on a 64-MDCT scanner while altering operator-selectable image noise and reconstruction slice thickness.


RESULTS
Using phantom dose measurements to adjust theoretic predictions, we constructed both a spreadsheet and a graph that visually display the interrelationships between operator-selected image noise and reconstruction slice thickness and the resulting patient dose.


CONCLUSIONS
This table and graph may help operators understand the trade-offs when prospectively trying to minimize dose and optimize image noise for selected reconstruction slice thicknesses on this type of 64-MDCT scanner.
Kanal
Kalpana M
KM
Department of Radiology, University of Washington Medical Center, 1959 NE Pacific St., Box 357115, Seattle, WA 98195-7115, USA. kkanal@u.washington.edu
Stewart
Brent K
BK
Kolokythas
Orpheus
O
Shuman
William P
WP
D000465:Algorithms; D001822:Body Burden; D003198:Computer Simulation; D006801:Humans; D008954:Models, Biological; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011874:Radiometry / Q000379:methods*; D012062:Relative Biological Effectiveness; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed / Q000295:instrumentation / Q000379:methods*