title: High-frequency ultrasound for evaluation of intimal thickness.
abstract: BACKGROUND
  The measurement of carotid intima-medial thickness is a well-validated measure of cardiovascular risk. Although atherosclerosis occurs in the intima, this arterial layer is not measured alone because of the limitation in ultrasound resolution with standard-frequency probes.
  
  
  METHODS
  We evaluated the feasibility of using a 55-MHz ultrasound system with high resolution to measure intima thickness in several vascular territories compared with a "standard" frequency probe.
  
  
  RESULTS
  The intima-medial thickness was measured in the brachial, radial, and tibial arteries in 10 healthy subjects and 5 subjects with peripheral arterial disease. The high-frequency ultrasound probe showed superior resolution compared with the standard-frequency probe, allowing for measurement of intima separately from media.
  
  
  CONCLUSIONS
  The intima can be measured independently of media with a high degree of reproducibility using a high-frequency probe. This technology may allow for early detection of cardiovascular risk and extend knowledge about the physiologic changes in early atherosclerotic development.
authors: Department of Medicine, Cardiovascular Division, Section of Vascular Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA. mohlere@uphs.upenn.edu
authors: Emile R
authors: ER
authors: Mohler
authors: Alexandra A
authors: AA
authors: Sibley
authors: Susan M
authors: SM
authors: Schultz
authors: Lifeng
authors: L
authors: Zhang
authors: Chandra M
authors: CM
authors: Sehgal
mesh_terms: D000328:Adult; D000368:Aged; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D004452:Echocardiography / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D008297:Male; D016491:Peripheral Vascular Diseases / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017539:Tunica Intima / Q000000981:diagnostic imaging*