Flemming Forsberg PhD, Presenter: Nothing to Disclose

Daniel Arthur Merton, Abstract Co-Author: Nothing to Disclose

Alan Stein, Abstract Co-Author: Nothing to Disclose

Kathryn J Lipcan, Abstract Co-Author: Nothing to Disclose

Donald Herzog, Abstract Co-Author: Nothing to Disclose

Laurence Needleman MD, Abstract Co-Author: Nothing to Disclose

To compare peak systolic velocities (PSVs) and degree of stenoses obtained with a novel, real time three-dimensional (i.e., 4D) Doppler ultrasound (US)scanner (the Encore PV; Vuesonix Sensors, Wayne, PA) to conventional Doppler US of carotid arteries (common=CCA; internal=ICA; external=ECA). Also to assess Encore PV volume flow (VF) measurements.

PSV of the CCA, ECA and ICA were obtained bilaterally in 70 patients referred for clinically indicated carotid US evaluations. The degree of stenosis in the ICA was also calculated based on the ICA PSV and on the ICA/CCA PSV ratio. In a subset of patients ICA stenosis was also assessed with MRA or CTA. The Encore PV, which detects all 3D blood flow velocity vectors within a volume, was used to obtain 10 s longitudinal volumes of the ICA, ECA and CCA. On the Encore PV, a reader determined the center line of the vessels and the PSV and VF were then automatically calculated. The error of the VF measurements was obtained by adding the results of the ICA and ECA VF and comparing it to the CCA VF. Data were compared using linear regression, kappa statistics and Bland-Altman analysis (due to the lack of independence).

Due to technical difficulties only 59 subjects (317 vessel segments) were available for analysis. Mean VF error was -4.1 % (standard deviation: 66.4%) on the Encore PV and was not significantly biased (p=0.57). The PSV measurements obtained with US and the Encore PV correlated in all 3 vessels (r>0.32; p<0.002). Bland-Altman analysis of US and Encore PV showed reasonable variation for PSV measurements in all 3 vessels. There was good agreement between the two methods for assessing the degree of stenosis based on the ICA PSV (κ of 0.57; p<0.001), but not based on the ICA/CCA PSV ratio. Excellent agreement was found between the Encore PV and concomitant imaging (MRA and CTA) for determining ICA stenosis (κ of 0.87; p<0.001) albeit based on a small data set (22 vessel segments).

A new semi-automated 4D Doppler device (the Encore PV) is comparable to conventional Doppler US for assessment of carotid stenoses. This work was supported by NIH HL065771.

A.S.,D.H.: Employee of VueSonix Sensors IncF.F.,L.N.: Formerly consultants to VueSonix Sensors IncF.F.: This work supported by NIH HL065771

Forsberg, F, Merton, D, Stein, A, Lipcan, K, Herzog, D, Needleman, L, Using a Novel Semi-automated 4D Doppler System to Assess Carotid Stenoses.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4410316.html