title: Distribution of calcification in carotid endarterectomy tissues: comparison of micro-computed tomography imaging with histology.
abstract: BACKGROUND
  Calcification in atherosclerotic plaques has been viewed as a marker of plaque stability, but whether calcification accumulates in specific anatomic sites in the carotid artery is unknown. We determined the burden and distribution of calcified plaque in carotid endarterectomy (CEA) tissues.
  
  
  METHODS
  A total of 22 CEA tissues were imaged with high-resolution micro-computed tomography (micro-CT). Total plaque burden and total calcium score using the Agatston method were quantified. The Agatston score (AS) was also normalized for tissue size. Plaque and calcium distribution were analyzed separately for three CEA regions: common segment (CS), bulb segment (BS), and internal/external segments (IES).
  
  
  RESULTS
  The average CEA tissue length was 40.83 (interquartile range [IQR] 33.31-42.41) mm with total plaque burden of 103.45 (IQR: 78.84-156.81) mm(3) and total AS of 38.58 (IQR 11.59-89.97). Total plaque volume was 21.02 (IQR: 14.47-25.42) mm(3) in the CS, 37.89 (22.59-48.32) mm(3) in the BS, and 54.05 (36.87-74.52) mm(3) in the IES. Of the 22 tissues, 15 had no calcium in the CS compared with three in the bulb and two in the IES. Normalized calcified plaque was most prevalent in the BS, the IES and was least prevalent in the CS. The overall correlation of calcification between histology sections and matched micro-CT images was 0.86 (p<0.001).
  
  
  CONCLUSIONS
  Calcified plaque is heterogeneously distributed in CEA tissues with most in the bulb and IES regions. The amount of calcification in micro-CT slices shows a high correlation with matched histology sections.
authors.affiliation: Co-primary authors (contributed equally) Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA.
authors.forename: Bashar
authors.initials: B
authors.lastname: Ababneh
authors.affiliation: Co-primary authors (contributed equally) Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA.
authors.forename: Loui
authors.initials: L
authors.lastname: Rejjal
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA.
authors.forename: Yashashwi
authors.initials: Y
authors.lastname: Pokharel
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA Michael E DeBakey VA Medical Center, Houston, Texas, USA Methodist DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Texas, USA.
authors.forename: Vijay
authors.initials: V
authors.lastname: Nambi
authors.affiliation: Department of Translational Imaging, Houston Methodist Research Institute, Houston, Texas, USA.
authors.forename: Xukui
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Translational Imaging, Houston Methodist Research Institute, Houston, Texas, USA.
authors.forename: Ching-Hsuan
authors.initials: CH
authors.lastname: Tung
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA.
authors.forename: Richard I
authors.initials: RI
authors.lastname: Han
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA Michael E DeBakey VA Medical Center, Houston, Texas, USA.
authors.forename: Addison A
authors.initials: AA
authors.lastname: Taylor
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA Michael E DeBakey VA Medical Center, Houston, Texas, USA.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Kougias
authors.affiliation: Methodist DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Texas, USA.
authors.forename: Alan B
authors.initials: AB
authors.lastname: Lumsden
authors.affiliation: Methodist DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Texas, USA.
authors.forename: Gerald
authors.initials: G
authors.lastname: Lawrie
authors.affiliation: Methodist DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Texas, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Reardon
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA Methodist DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Texas, USA.
authors.forename: Christie M
authors.initials: CM
authors.lastname: Ballantyne
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA.
authors.forename: Joel D
authors.initials: JD
authors.lastname: Morrisett
authors.affiliation: Division of Atherosclerosis and Vascular Medicine, Department of Medicine, Baylor College of Medicine, Texas, USA Methodist DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Texas, USA gbrunner@bcm.edu.
authors.forename: Gerd
authors.initials: G
authors.lastname: Brunner
mesh_terms: D001707:Biopsy, Needle; D002114:Calcinosis / Q000000981:diagnostic imaging* / Q000473:pathology*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D015331:Cohort Studies; D016894:Endarterectomy, Carotid / Q000379:methods; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D008297:Male; D015588:Observer Variation; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging / Q000473:pathology; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D046509:Tissue Culture Techniques; D055114:X-Ray Microtomography / Q000379:methods
keywords: Agatston score; Carotid endarterectomy; computed tomography; histology; plaque