Tomomi Omura, Presenter: Nothing to Disclose

Noriyuki Takahashi, Abstract Co-Author: Nothing to Disclose

Hideto Toyoshima BSc, Abstract Co-Author: Nothing to Disclose

Yongbum Lee PhD, Abstract Co-Author: Nothing to Disclose

Toshibumi Kinoshita MD, PhD, Abstract Co-Author: Nothing to Disclose

CT perfusion (CTP) is useful in the evaluation of ischemia, but radiation exposure of CTP is greater than other CT examinations. Low dose scan reduces radiation exposure, but leads to an increase of image noise. The teaching points are 1. To review ways to reduce image noise in CTP. 2. To learn the difficulty of evaluation of the effect of iterative reconstruction (IR) methods. 3. To understand a way to create a digital phantom for evaluating noise reduction. 4. To assess the evaluation of the effect of IR method on noise reduction using the digital phantom.    

Ways to improve the image noise              - Reconstruction kernel              - De-noising filter              - IR method Acquirement of digital phantom source images              - CTP images obtained without contrast medium injection Design of digital phantom              - A digital phantom obtained by adding computer-simulated middle cerebral arteries to non enhancement images of a phantom Evaluation of noise reduction by use of the digital phantom              - IR method vs. FBP method Conclusion We found that a 43% reduction of image noise was obtained using an IR method by use of the digital phantom, and demonstrated usefulness of the digital phantom to evaluate the effect of noise reduction without contrast medium injection for CTP.  

http://abstract.rsna.org/uploads/2014/14007756/14007756_7xup.pdf

Omura, T, Takahashi, N, Toyoshima, H, Lee, Y, Kinoshita, T, How to Obtain a Digital Perfusion Phantom to Evaluate the Effect of Iterative Reconstruction Methods on Noise Reduction in Brain CT Perfusion.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14007756.html