Assessment of the effect of percutaneous ethanol injection in autonomously functioning thyroid nodules by colour-coded duplex sonography

Percutaneous ethanol injection (PEI) is an effective treatment for autonomously functioning thyroid nodules (AFTNs). The aims of this study were to assess: (1) the ultrasound (US) and colour-coded duplex sonography (CCDS) baseline and post-therapy patterns of AFTN, and (2) the contribution of CCDS in determining the efficacy and optimum duration of PEI. Forty AFTNs were evaluated by US and CCDS before, during and 6 and 12 months after PEI. Four grades of increasing vascularity were arbitrarily identified at CCDS (0-1-2-3). These data were compared with thyroid scintiscan and hormonal findings. All nodules showed a striking volume decrease. After treatment a hypoechoic pattern and blurred outlines on US were associated with a higher percentage volume reduction. Soon after PEI a reduction in the vascularity score was noticed in 29 of 40 of AFTNs. Pre- and post-treatment vascular score distributions were significantly different. It is concluded that a vascular score decrease to grade 0–1 at the end of PEI is an index of successful treatment.