title: Transcutaneous very-high-resolution ultrasound to quantify arterial wall layers of muscular and elastic arteries: validation of a method.
abstract: BACKGROUND
  High-resolution ultrasound (HRU) is used to measure carotid intima-media thickness (IMT). We postulated that very-high-resolution ultrasound (VHRU, 25-55MHz) provides more detailed information on arterial morphology.
  
  
  METHODS
  Rabbit and pig arterial specimens and artificial elastin membranes were studied with HRU and VHRU, and compared to histology. Bilateral carotid, brachial, radial, ulnar, femoral, and tibial arteries were imaged in vivo in 15 humans to determine the precision of VHRU and in 53 teenagers to compare VHRU to HRU.
  
  
  RESULTS
  The assessment of IMT, adventitia thickness (AT) and combined intima-media-adventitia thickness (IMAT) in muscular arteries was accurate and precise by VHRU with the exception that the AT of the smallest arteries was not delineated with 25MHz. VHRU was accurate and precise for IMAT in small and for IMT in large elastic arteries and allowed to qualitatively assess elastin fibers of the media. HRU was accurate for IMT of large muscular and elastic arteries only. Intima thickness (IT) was grossly overestimated by both VHRU and HRU.
  
  
  CONCLUSIONS
  Transcutaneous VHRU provides a noninvasive method of quantifying elastic and muscular arterial AT, IMT and IMAT in children and adults, but neither VHRU nor HRU is able to assess IT in non-diseased vessels.
authors.affiliation: Division of Cardiology, Labatt Family Heart Centre, The Hospital for Sick Children, University of Toronto, Toronto, Canada. taisto.sarkola@helsinki.fi
authors.forename: Taisto
authors.initials: T
authors.lastname: Sarkola
authors.forename: Andrew
authors.initials: A
authors.lastname: Redington
authors.forename: Fred
authors.initials: F
authors.lastname: Keeley
authors.forename: Timothy
authors.initials: T
authors.lastname: Bradley
authors.forename: Edgar
authors.initials: E
authors.lastname: Jaeggi
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001158:Arteries / Q000000981:diagnostic imaging; D002648:Child; D002675:Child, Preschool; D003238:Connective Tissue / Q000000981:diagnostic imaging*; D004548:Elasticity; D004549:Elastin / Q000378:metabolism; D005557:Formaldehyde / Q000737:chemistry; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D011817:Rabbits; D015203:Reproducibility of Results; D013552:Swine; D017539:Tunica Intima / Q000000981:diagnostic imaging*; D017540:Tunica Media / Q000000981:diagnostic imaging*; D014463:Ultrasonography / Q000379:methods*
chemical_list: D005557:Formaldehyde; D004549:Elastin