CT has become a routine medical tool in diagnosis of diseases and visualization of critical interventional procedures. The number of CT examinations has significantly increased over the past two decades in the US, and reached approximately 72 million in 2007 alone [5,8]. According to the 2009 report from the National Council on Radiation Protection &Measurements, CT examinations are responsible for approximately 50% of the medical radiation exposure and nearly 25% of the total population exposure [8]. Recent studies suggested that approximately 29,000 future cancers could be related to CT examinations performed in the US in 2007 alone [1-3], which is equivalent to about 2% of the cancers that are diagnosed annually in the US [1,4]. As the number of CT examinations continues to increase from the 2007 rate, the radiation dose associated with CT and its potential for the increase in radiation-induced cancers have become a public health issue (LA Times, Oct 2009, NY Times Jan 2010, [1-7]). Software that reduces the required radiation dose without impacting image quality, and that can be applied to existing and future CT scanners without hardware modification will have a dramatic positive impact on public health and can provide a distinctive advantage for the CT scanner manufacturer (OEM) that offers it. In this proposal, we aim to perform significant CT dose reduction by using an innovative Fourier-based iterative method called Equally Sloped Tomography (EST).The proposed algorithm a) can be adapted to current and future generations of CT scanners without modification of the hardware, b) does not require interpolation in the Fourier space [9-19] which is generally less accurate, and c) physical and mathematical constraints can naturally be incorporated into the algorithm. Our preliminary studies indicate that EST can reduce the CT dose by ~70%, while producing comparable or better image resolution, quality and contrast than the full-dose Filtered Back Projection algorithm (FBP) reconstructions [17, 18]. TomoSoft Technologies, LLC has executed an exclusive licensing agreement with UCLA for the EST algorithm. In this proposal, TomoSoft and UCLA will further prove and co-develop the algorithm. We have formed an interdisciplinary team with extensive experience in algorithm development, applied mathematics and medical physics. Building upon the success of the preliminary results, the goal of this proposal is to a) test a central hypothesis that EST can be applied to significantly reduce the radiation dose in medical CT without sacrificing the image quality, contrast and resolution, and b) expand the algorithm applicability to the cone-beam geometry CT scanners, which are more prevalent in clinical settings today.
Public Health Relevance: According to the 2009 report from the National Council on Radiation Protection &Measurements, CT examinations are responsible for approximately 50% of the medical radiation exposure and nearly 25% of the total population exposure [8]. Recent studies suggested that approximately 29,000 future cancers could be related to CT examinations performed in the US in 2007 alone [1-3], which is equivalent to about 2% of the cancers that are diagnosed annually in the US [1, 4]. In this proposal, we aim to perform significant CT dose reduction by utilizing an innovative CT reconstruction method
