The aim of this study was to evaluate whether TTFCA (total triterpenic fraction of Centella asiatica), was effective, by modulating collagen production, in a period of 12 months, increasing the echogenicity of echolucent plaques at the femoral bifurcation. Hypoechoic atherosclerotic plaques have been found to be associated with an increased evidence of cerebrovascular events. In this type of plaques stromal composition is limited as the collagen component is generally very low; the plaque composition is mainly due to lipid accumulation or thrombosis. The aim of this study was the evaluation of echogenicity of hyperechoic plaques and how it could be modified by a drug acting on the modulation of collagen synthesis. Antiplatelet agents were used in all patients; cholesterol-lowering agents were used in 34% of patients in the treatment group and in 36% in the placebo group. TTFCA was used at the dose of 60 mg thrice daily (oral tablets). Of the 60 included subjects 26 completed the study in the treatment group and 24 in the placebo group. At inclusion the average GSM in the treatment group was 14 (SD 3) and 14.3 (SD 3) in controls. At 12 months GSM was increased up to 22.8 (SD 4) in the treatment group and it was 15 (SD 3) in controls. Considering texture no significant changes were observed in controls while a qualitative increase in homogenicity was observed in the TTFCA group. Plaque size measured at the beginning and at the end of the study showed a median increase in size, in controls (23%; range 0%-44%); it was unchanged in the TTFCA group (variation 7%; 4%-26%). In conclusion in the treatment group plaques increased in echogenicity and in homogenicity; size and stenosis remained unchanged. Modulating the scarring process within echolucent plaques (low echogenicity, high echolucency, with a very low collagen/stromal component), possibly by collagen modulation, makes plaques more stable. This has been achieved and documented in the present study by an increase in the gray-scale median (plaques become more echogenic, more 'white'). The variation in GSM is generally associated with a lower risk of wall thrombosis, rupture and embolization. These observations indicate a positive action of TTFCA on the stabilization of hypoechoic, low-density femoral plaques.