Résumé
Objective To explore the value of biomechanics parameter of rabbit abdominal aortic atheroma using velocity vector imaging(VVI).Methods Ten of 45 male New Zealand rabbits were chosen as normal control group randomly,the rest experimental rabbits were made atheromatous plaque model.The rabbits were examined by two-dimensional ultrasound and VVI respectively.The intima-media thickness(IMT) or thickness of plaques of abdominal aorta 1 cm from right renal artery branch were recorded.Maximum tangential velocity,strain and strain rate of IMT or plaques were measured using VVI.Then the rabbits were killed for pathological and immuno-histochemical examination.Results Based on pathology,the rabbites were divided into 4 groups:control group(group A,n=10),group of pathological endometrial thickening(group B,n=9),group of thick fibrous cap atheromatous plaques (group C,n=15) and group of thin fibrous cap atheromatous plaques (group D,n=11).The difference of plaques thickness and biochemical indicators had no statistically significant between group B and C(P>0.05),both bigger than group A and B (P0.46×10-2 cm/s,Smax>0.37%,SRmax>1.415×10-2 s-1 to find the vulnerable plaques,the sensitivity were 75.0%,84.4%,84.4% respectively,specificity were 70.8%,91.7%,83.3% respectively.Conclusions VVI can identify plaque biomechanics parameter of different progression periods,which is expected to be a reliable method to find vulnerable plaques earlier in clinic.