title: Motion Correction of 18F-NaF PET for Imaging Coronary Atherosclerotic Plaques.
abstract: Ruptured coronary atherosclerotic plaques commonly cause acute myocardial infarction. It has recently been shown that active microcalcification in the coronary arteries, one of the features that characterizes vulnerable plaques at risk of rupture, can be imaged using (18)F-NaF PET. We aimed to determine whether a motion correction technique applied to gated (18)F-NaF PET images could enhance image quality and improve uptake estimates.
  
  
  METHODS
  Seventeen patients with myocardial infarction (n = 7) or stable angina (n = 10) underwent (18)F-NaF PET and prospective coronary CT angiography. PET data were reconstructed in 4 different ways: the first was 1 gated bin (end-diastolic phase with 25% of the counts), the second was 4 gated bins (consecutive 25% segments), the third was 10 gated bins (consecutive 10% segments), and the fourth was ungated. Subsequently, with data from either 4 or 10 bins, gated PET images were registered using a local, nonlinear motion correction method guided by the extracted coronary arteries from CT angiography. Global noise levels and target-to-background ratios (TBR) defined on manually delineated coronary plaque lesions were compared to assess image quality and uptake estimates.
  
  
  RESULTS
  Compared with the reference standard of using only 1 bin of PET data, motion correction using 10 bins of PET data reduced image noise by 46% (P < 0.0001). TBR in positive lesions for 10-bin motion-corrected data was 11% higher than for 1-bin data (1.98 [interquartile range, 1.70-2.37] vs. 1.78 [1.58-2.16], P = 0.0027) and 33% higher than for ungated data (1.98 [1.70-2.37] vs. 1.49 [1.39-1.88], P < 0.0001).
  
  
  CONCLUSIONS
  Motion correction of gated (18)F-NaF PET/coronary CT angiography is feasible, reduces image noise, and increases TBR. This improvement may allow more reliable identification of vulnerable coronary artery plaques using (18)F-NaF PET.
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Rubeaux
authors.affiliation: University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Nikhil V
authors.initials: NV
authors.lastname: Joshi
authors.affiliation: University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Marc R
authors.initials: MR
authors.lastname: Dweck
authors.affiliation: University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Alison
authors.initials: A
authors.lastname: Fletcher
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and.
authors.forename: Manish
authors.initials: M
authors.lastname: Motwani
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and.
authors.forename: Louise E
authors.initials: LE
authors.lastname: Thomson
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and.
authors.forename: Guido
authors.initials: G
authors.lastname: Germano
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and.
authors.forename: Damini
authors.initials: D
authors.lastname: Dey
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and.
authors.forename: Debiao
authors.initials: D
authors.lastname: Li
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Berman
authors.affiliation: University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: David E
authors.initials: DE
authors.lastname: Newby
authors.affiliation: Cedars-Sinai Medical Center, Los Angeles, California; and piotr.slomka@cshs.org.
authors.forename: Piotr J
authors.initials: PJ
authors.lastname: Slomka
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D005462:Fluorine Radioisotopes; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D009068:Movement; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging* / Q000503:physiopathology; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D012189:Retrospective Studies; D059629:Signal-To-Noise Ratio; D012969:Sodium Fluoride
chemical_list: D005462:Fluorine Radioisotopes; D012969:Sodium Fluoride
keywords: 18F-NaF; coronary atherosclerotic plaques; 18F-sodium fluoride PET; microcalcification; motion correction