The objective of this proposal is to develop clinically viable strategies for the quantitative estimation of myocardial blood flow (MBF) from dynamic computed tomography (CT) imaging with low radiation doses comparable to those received in common nuclear myocardial perfusion studies. Despite the proven clinical value of quantifying MBF (in ml/g/min), there are no widespread clinical methods to easily measure MBF in absolute units. Dynamic CT offers the potential to quantify flow, but the radiation dose imparted from these studies prohibits widespread acceptance.
The specific aims of the proposal are to develop 1) optimal myocardial blood flow estimation methods, 2) low-dose dynamic CT acquisition strategies for MBF estimation, 3) unbiased data restoration algorithms and 4) image reconstruction methods based on trading off spatial resolution for noise reduction and constraining noise with a priori knowledge.
These aims will be developed with simulations of dynamic contrast enhanced CT imaging and evaluated with patient exams. We hypothesize that accurate subendo- and subepi-cardial MBF estimates can be determined with low- dose dynamic CT through selection of acquisition strategies and judicious application of noise reduction strategies. This work proposes novel low-dose acquisition and data/image enhancement strategies to enable accurate quantitative estimates of blood flow in absolute units of ml/g/min. These methods will allow for substantial reductions in radiation dose, which is essential for patient safety, clinical application of dynamic CT for MBF measurement, and for other proven applications of dynamic CT. This work will position cardiac dynamic CT as a safe, easy, and widely available tool for quantitative MBF estimation, providing valuable clinical information for quantification of flow limiting disease, minimizing unnecessary catheterization procedures, informing therapy choices, and developing new therapies.

Public Health Relevance

A quantitative estimate of blood flow in the heart provides valuable clinical information regarding the severity and extent of coronary heart disease. Dynamic computed tomography (CT) offers the potential to quantify blood flow, but it is not widely accepted because of the radiation dose associated with these studies. This proposal will develop strategies to substantially reduce the radiation dose from dynamic CT, enabling quantitative myocardial blood flow estimation from an easy, widely available, and safe CT imaging study.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL109327-03
Application #
8650918
Study Section
Special Emphasis Panel ()
Program Officer
Danthi, Narasimhan
Project Start
2012-04-17
Project End
2017-03-31
Budget Start
2014-04-01
Budget End
2015-03-31
Support Year
3
Fiscal Year
2014
Total Cost
$407,380
Indirect Cost
$114,534
Name
University of Washington
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
605799469
City
Seattle
State
WA
Country
United States
Zip Code
98195
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Bindschadler, Michael; Modgil, Dimple; Branch, Kelley R et al. (2014) Simulation Evaluation of Quantitative Myocardial Perfusion Assessment from Cardiac CT. Proc SPIE Int Soc Opt Eng 9033:903303
Nesterov, Sergey V; Deshayes, Emmanuel; Sciagrà, Roberto et al. (2014) Quantification of myocardial blood flow in absolute terms using (82)Rb PET imaging: the RUBY-10 Study. JACC Cardiovasc Imaging 7:1119-27
Alessio, Adam M; MacDonald, Lawrence R (2013) Quantitative material characterization from multi-energy photon counting CT. Med Phys 40:031108