Jonathan Matthew Rubin, Presenter: Nothing to Disclose

Hua Xie DPHIL, Abstract Co-Author: Nothing to Disclose

Kang Kim DPHIL, Abstract Co-Author: Nothing to Disclose

William F. Weitzel MD, Abstract Co-Author: Nothing to Disclose

Stanislav Emelianov PhD, Abstract Co-Author: Nothing to Disclose

Salavat Aglyamov PhD, Abstract Co-Author: Nothing to Disclose

Thomas W. Wakefield MD, Abstract Co-Author: Nothing to Disclose

Matthew O'Donnell PhD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

To determine the utility of ultrasound elasticity imaging for aging deep venous thrombosis(DVT) in human patients.

57 patients, 30 with acute DVT and 27 with chronic DVT, were studied. The acute DVT patients had no prior history of DVT, had proven calf or thigh DVTs by duplex venous ultrasound, and had symptoms or signs of DVT for two weeks or less. Chronic DVT patients were subjects without symptoms, who had Greenfield filters, and had been followed for known DVTs for a year or greater. Scanning was performed using a 5 MHz linear array scanhead on a Siemens Elegra (Siemens Ultrasound, Issaquah, WA) ultrasound scanner during continuous, freehand external deformation of each thrombus using the ultrasound scanhead. Strain estimates for the deformation of each thrombus were based on a 2D phase-sensitive speckle tracking algorithm. The strains in the thrombi were normalized to the average strain between the skin surface and the back wall of the vein. Statistical analyses were performed using a two-tailed T-test assuming unequal variances and ROC analysis.

Seven patients were excluded from analysis, three with acute and four with chronic thrombi. Five were excluded because the overall average deformation was too small (<1%), and two of the chronic subjects were excluded because the thrombi were too small to track, i.e. the thrombi could not be identified retrospectively during analysis. In the remaining 50 subjects, the difference in the mean strains between chronic and acute DVTs was highly significant (p < 10-9). The area under the ROC curve suggests that the acute and chronic DVT populations are well separated. (Az = 0.977 ± 0.018(std. err.)).

Based on these results, it seems clear that ultrasound elasticity imaging can discriminate between acute and chronic DVT with a very high degree of accuracy. This discrimination is important, since the therapy of DVT depends on thrombus age. All of these analyses were performed off–line, and the difficulties encountered in the seven excluded subjects would be overcome with realtime strain estimation, which is under development.

J.M.R.,H.X.,K.K.,W.F.W.,S.E.,S.A.,T.W.W.,M.O.: Equipment and research collaboration with Siemens Medical Systems.

Rubin, J, Xie, H, Kim, K, Weitzel, W, Emelianov, S, Aglyamov, S, Wakefield, T, O'Donnell, M, et al, , Ultrasound Elasticity Imaging for Aging Deep Venous Thrombosis in Humans.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4412298.html