title: Accurate quantification of atherosclerotic plaque volume by 3D vascular ultrasound using the volumetric linear array method.
abstract: BACKGROUND
  Direct quantification of atherosclerotic plaque volume by three-dimensional vascular ultrasound (3DVUS) is more reproducible than 2DUS-based three-dimensional (2D/3D) techniques that generate pseudo-3D volumes from summed 2D plaque areas; however, its accuracy has not been reported. We aimed to determine 3DVUS accuracy for plaque volume measurement with special emphasis on small plaques (a hallmark of early atherosclerosis).
  
  
  METHODS
  The in vitro study consisted of nine phantoms of different volumes (small and medium-large) embedded at variable distances from the surface (superficial vs. >5 cm-depth) and comparison of 3DVUS data generated using a novel volumetric-linear array method with the real phantom volumes. The in vivo study was undertaken in a rabbit model of atherosclerosis in which 3DVUS and 2D/3D volume measurements were correlated against gold-standard histological measurements.
  
  
  RESULTS
  In the in vitro setting, there was a strong correlation between 3DVUS measures and real phantom volume both for small (3.0-64.5 mm(3) size) and medium-large (91.1-965.5 mm(3) size) phantoms embedded superficially, with intraclass correlation coefficients (ICC) of 0.99 and 0.98, respectively; conversely, when phantoms were placed at >5 cm, the correlation was only moderate (ICC = 0.67). In the in vivo setting there was strong correlation between 3DVUS-measured plaque volumes and the histological gold-standard (ICC = 0.99 [4.02-92.5 mm(3) size]). Conversely, the correlation between 2D/3D values and the histological gold standard (sum of plaque areas) was weaker (ICC = 0.87 [49-520 mm(2) size]), with large dispersion of the differences between measurements in Bland-Altman plots (mean error, 79.2 mm(2)).
  
  
  CONCLUSIONS
  3DVUS using the volumetric-linear array method accurately measures plaque volumes, including those of small plaques. Measurements are more accurate for superficial arterial territories than for deep territories.
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Hospital Universitario HM Montepríncipe, 25 Montepríncipe Ave, 28660 Boadilla del Monte, Spain. Electronic address: beatriz.lopez@cnic.es.
authors.forename: Beatriz
authors.initials: B
authors.lastname: López-Melgar
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Hospital Universitario HM Montepríncipe, 25 Montepríncipe Ave, 28660 Boadilla del Monte, Spain. Electronic address: leticia.fernandez@cnic.es.
authors.forename: Leticia
authors.initials: L
authors.lastname: Fernández-Friera
authors.affiliation: Philips Healthcare, 1 María de Portugal St, 28050 Madrid, Spain. Electronic address: javier.sanchez.gonzalez@philips.com.
authors.forename: Javier
authors.initials: J
authors.lastname: Sánchez-González
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Hospital Universitario Clínico San Carlos, Profesor Martín Lagos St, 28040 Madrid, Spain. Electronic address: jeanpaul.vilchez@gmail.com.
authors.forename: Jean Paul
authors.initials: JP
authors.lastname: Vilchez
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Hospital Universitario Clínico San Carlos, Profesor Martín Lagos St, 28040 Madrid, Spain. Electronic address: albertocecconi@hotmail.com.
authors.forename: Alberto
authors.initials: A
authors.lastname: Cecconi
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain. Electronic address: jesus.mateo@cnic.es.
authors.forename: Jesús
authors.initials: J
authors.lastname: Mateo
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Friedman School of Nutrition Science and Policy, Tufts University, 150 Harrison Ave, MA, 02111 Boston, USA. Electronic address: jlpenalvo@cnic.es.
authors.forename: José L
authors.initials: JL
authors.lastname: Peñalvo
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain. Electronic address: belen.oliva@cnic.es.
authors.forename: Belén
authors.initials: B
authors.lastname: Oliva
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain. Electronic address: josemanuel.garcia@externo.cnic.es.
authors.forename: Jose M
authors.initials: JM
authors.lastname: García-Ruiz
authors.affiliation: Philips Healthcare, 1 María de Portugal St, 28050 Madrid, Spain. Electronic address: steve.kauffman@philips.com.
authors.forename: Steve
authors.initials: S
authors.lastname: Kauffman
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Hospital Universitario La Princesa, 62 Diego Leon St, 28006 Madrid, Spain. Electronic address: ljborreguero@gmail.com.
authors.forename: Luis Jesús
authors.initials: LJ
authors.lastname: Jiménez-Borreguero
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Universidad Complutense de Madrid and Ciber de Enfermedades Respiratorias (CIBERES), 2 Séneca Ave, 28040 Madrid, Spain. Electronic address: ruizcabe@cnic.es.
authors.forename: Jesús
authors.initials: J
authors.lastname: Ruiz-Cabello
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Hospital Universitario Clínico San Carlos, Profesor Martín Lagos St, 28040 Madrid, Spain. Electronic address: antonioignacio.fernandez@cnic.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Fernández-Ortiz
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; IIS-Fundación Jiménez Díaz Hospital, 2 Reyes Católicos Ave, 28040 Madrid, Spain. Electronic address: bibanez@cnic.es.
authors.forename: Borja
authors.initials: B
authors.lastname: Ibáñez
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 3 Melchor Fernández Almagro St, 28029 Madrid, Spain; Mount Sinai Heart, Icahn School of Medicine, 1 Gustave L. Levy Place, Box 1030, New York City, NY 10029, USA. Electronic address: valentin.fuster@mountsinai.org.
authors.forename: Valentín
authors.initials: V
authors.lastname: Fuster
mesh_terms: D000818:Animals; D015331:Cohort Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional; D016014:Linear Models; D019047:Phantoms, Imaging; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging*; D011817:Rabbits; D015203:Reproducibility of Results; D012984:Software; D014463:Ultrasonography
keywords: Accuracy; Atherosclerotic plaque; Gold-standard; Plaque volume; Three-dimensional; Vascular ultrasound