title: Influence of increasing convolution kernel filtering on plaque imaging with multislice CT using an ex-vivo model of coronary angiography.
abstract: OBJECTIVE
  To assess the variability in attenuation of coronary plaques with multislice CT-angiography (MSCT-CA) in an ex-vivo model with varying convolution kernels.
  
  
  METHODS
  MSCT-CA (Sensation 16, Siemens) was performed in three ex-vivo left coronary arteries after instillation of contrast material solution (Iomeprol 400 mgI/ml, dilution: 1/80). The specimens were placed in oil to simulate epicardial fat. Scan parameters: slices 16/0.75 mm, rotation time 375 ms, feed/rotation 3.0 mm, mAs 500, slice thickness 1 mm, and FOV 50 mm. Datasets were reconstructed using 4 different kernels (B30f-smooth, B36f-medium smooth, B46f-medium, and B60f-sharp). Each scan was scored for the presence of plaques. Once a plaque was detected, the operator performed attenuation measurements (HU) in coronary lumen, oil, calcified and soft plaque tissue using the same settings in all datasets. The results were compared with T-test and correlated with Pearson's test.
  
  
  RESULTS
  Overall, 464 measurements were performed. Significant differences (p<0.05) were found for the mean attenuation of lumen (B30f/B36f, B30f/B60f, B36f/B46f, B36f/B60f, and B46f/B60f), oil (B30f/B36f, B30f/B46f, B30f/B60f, B36f/B46f, and B46f/B60f), calcium (all kernels), and plaque (B30f/B36f, B30f/B46f, B30f/B60f, and B46f/B60f) using 4 different kernels. The attenuation values (mean+/-SD) within the lumen (246+/-6, 215+/-13, 248+/-5, and 270+/-7), oil (-123+/-3, -127+/-1, -121+/-6, and -127+/-4), calcified plaque tissue (703+/-334, 739+/-364, 817+/-381, and 1181+/-503), and soft plaque tissue (134+/-56, 111+/-49, 120+/-56, and 102+/-41) showed high correlation (p<0.001) when attenuation of all structures were compared in different kernels.
  
  
  CONCLUSIONS
  Use of sharper convolution kernels significantly increases the attenuation of the calcium within coronary plaques and reduces the attenuation of soft plaque tissue.
authors.affiliation: Dipartimento di Radiologia, Erasmus Medical Cencter, Rotterdam, The Netherlands. filippocademartiri@hotmail.com
authors.forename: Filippo
authors.initials: F
authors.lastname: Cademartiri
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Runza
authors.forename: Nico R
authors.initials: NR
authors.lastname: Mollet
authors.forename: Giacomo
authors.initials: G
authors.lastname: Luccichenti
authors.forename: Manuel
authors.initials: M
authors.lastname: Belgrano
authors.forename: Pamela
authors.initials: P
authors.lastname: Somers
authors.forename: Michiel
authors.initials: M
authors.lastname: Knaapen
authors.forename: Stefan
authors.initials: S
authors.lastname: Verheye
authors.forename: Nico
authors.initials: N
authors.lastname: Bruining
authors.forename: Ronald
authors.initials: R
authors.lastname: Hamers
authors.forename: Massimo
authors.initials: M
authors.lastname: Midiri
authors.forename: Pim J
authors.initials: PJ
authors.lastname: De Feyter
authors.forename: Gabriel P
authors.initials: GP
authors.lastname: Krestin
mesh_terms: D000368:Aged; D001344:Autopsy; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000473:pathology; D003331:Coronary Vessels / Q000473:pathology; D003627:Data Interpretation, Statistical; D005260:Female; D006652:Histological Techniques; D006801:Humans; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D014057:Tomography, X-Ray Computed / Q000379:methods*