title: Tissue Doppler imaging of carotid plaque wall motion: a pilot study.
abstract: BACKGROUND
  Studies suggest the physical and mechanical properties of vessel walls and plaque may be of clinical value in the diagnosis and treatment of cardiovascular atherosclerotic disease. The purpose of this pilot study was to investigate the potential clinical application of ultrasound Tissue Doppler Imaging (TDI) of Arterial Wall Motion (AWM) and to quantify simple wall motion indices in normal and diseased carotid arteries.
  
  
  METHODS
  224 normal and diseased carotid arteries (0-100% stenoses) were imaged in 126 patients (age 25-88 years, mean 68 +/- 11). Longitudinal sections of the carotid bifurcation were imaged using a Philips HDI5000 scanner and L12-5 probe under optimized TDI settings. Temporal and spatial AWMs were analyzed to evaluate the vessel wall displacements and spatial gradients at peak systole averaged over 5 cardiac cycles.
  
  
  RESULTS
  AWM data were successfully extracted in 91% of cases. Within the carotid bifurcation/plaque region, the maximum wall dilation at peak systole ranged from -100 to 750 microns, mean 335 +/- 138 microns. Maximum wall dilation spatial gradients ranged 0-0.49, mean 0.14 +/- 0.08. The AWM parameters showed a wide variation and had poor correlation with stenoses severity. Case studies illustrated a variety of pertinent qualitative and quantitative wall motion features related to the biophysics of arterial disease.
  
  
  CONCLUSIONS
  Our clinical experience, using a challenging but realistic imaging protocol, suggests the use of simple quantitative AWM measures may have limitations due to high variability. Despite this, pertinent features of AWM in normal and diseased arteries demonstrate the potential clinical benefit of the biomechanical information provided by TDI.
authors.affiliation: Department of Medical Physics, University Hospitals of Leicester NHS Trust, Leicester, UK. kumar.ramnarine@uhl-tr.nhs.uk
authors.forename: Kumar V
authors.initials: KV
authors.lastname: Ramnarine
authors.forename: Tim
authors.initials: T
authors.lastname: Hartshorne
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Sensier
authors.forename: May
authors.initials: M
authors.lastname: Naylor
authors.forename: Joanne
authors.initials: J
authors.lastname: Walker
authors.forename: A Ross
authors.initials: AR
authors.lastname: Naylor
authors.forename: Ronney B
authors.initials: RB
authors.lastname: Panerai
authors.forename: David H
authors.initials: DH
authors.lastname: Evans
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena / Q000379:methods; D002339:Carotid Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D015150:Echocardiography, Doppler / Q000379:methods*; D004548:Elasticity; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009068:Movement; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical