title: Carotid plaque characteristics on magnetic resonance plaque imaging following long-term cilostazol therapy.
abstract: BACKGROUND
  Cilostazol is an antiplatelet agent that can induce the regression of atherosclerosis. However, its long-term effects on plaque involution of the cervical carotid arteries remain unknown. Thus, we aimed to evaluate the effect of long-term cilostazol administration on carotid plaques using quantitative magnetic resonance (MR) plaque imaging.
  
  
  METHODS
  Sixteen consecutive patients with carotid stenosis were examined using T1-weighted MR plaque imaging at baseline, 6 months, and 12 months after initiation of 200 mg per day of cilostazol. We calculated the contrast ratio of the carotid plaque against the sternocleidomastoid muscle and percent areas of the intraplaque fibrous tissue, lipid/necrosis, and hemorrhage components using automated software. We also measured the volume and echogenicity of the plaques using 3-dimensional ultrasonography.
  
  
  RESULTS
  The contrast ratio of the carotid plaque significantly decreased during the cilostazol administration (median 1.07, 1.04, and 1.00 at baseline, 6 months, and 12 months, respectively; P = .03). Furthermore, the area of the fibrous components significantly increased (73.9%, 80.3%, and 85.7%, respectively; P = .03) and that of the lipid/necrotic components significantly decreased (25.2%, 19.2%, and 14.3%, respectively; P = .04). There were no substantial changes in plaque volume or echogenicity on ultrasonography.
  
  
  CONCLUSIONS
  Signal alterations on MR plaque imaging indicated the increase of fibrous components and the decrease of lipid/necrotic components in the carotid plaque during the cilostazol therapy.
authors.affiliation: Department of Neurology and Gerontology, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Japan. Electronic address: maooura@iwate-med.ac.jp.
authors.forename: Mao
authors.initials: M
authors.lastname: Yamaguchi Oura
authors.affiliation: Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Sasaki
authors.affiliation: Department of Neurology and Gerontology, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Ohba
authors.affiliation: Department of Neurology and Gerontology, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Narumi
authors.affiliation: Department of Neurology and Gerontology, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Japan.
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Oura
authors.affiliation: Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Japan.
authors.forename: Ikuko
authors.initials: I
authors.lastname: Uwano
authors.affiliation: Department of Neurology and Gerontology, Institute for Biomedical Sciences, Iwate Medical University, Morioka, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Terayama
mesh_terms: D000368:Aged; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D000077407:Cilostazol; D005260:Female; D005355:Fibrosis; D006801:Humans; D021621:Imaging, Three-Dimensional; D020300:Intracranial Hemorrhages / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology*; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D013777:Tetrazoles / Q000627:therapeutic use*; D016896:Treatment Outcome; D014463:Ultrasonography
chemical_list: D010975:Platelet Aggregation Inhibitors; D013777:Tetrazoles; D000077407:Cilostazol
keywords: Atherosclerotic plaque; carotid stenosis; cilostazol; magnetic resonance imaging; plaque imaging