Imaging manifestation of conventional and contrast-enhanced ultrasonography in percutaneous microwave ablation for the treatment of uterine fibroids

Objectives: To evaluate the image changes and the relationship between conventional ultrasonography and contrast-enhanced ultrasound (CEUS) in the perioperative period of microwave (MW) ablation for uterine fibroids; to guide clinical ablation therapy and evaluate the efficacy of MW. Methods: Twenty-nine patients with 31 uterine fibroids were recruited in this study. All patients received conventional ultrasound as well as CEUS examination before, immediately after and 12–24 h after MW, in order to detect variations of echo and characteristics of blood supply. t-Tests were used to compare the hyperecho area on gray-scale ultrasound to immediately after ablation non-enhanced CEUS measurements, as well as to compare the immediately after ablation non-enhanced CEUS measurements to the 12–24 h after ablation measurements. Results: Immediately after ablation, the average hyperecho area in gray-scale was 82.20 ± 72.32 cm3; the average non-enhancement area was 76.34 ± 70.63 cm3 by CEUS, showing a strong correlation (r = 0.997, P < 0.01) to the hyperecho area in gray-scale. The average non-enhancement area measured by CEUS immediately after ablation was 90.55 ± 74.41 cm3 and average 12–24 h after ablation was 98.29 ± 78.25 cm3; no statistically significant difference was detected between the two time points (P > 0.05). Conclusions: Measurements made by hyperechoic range on gray-scale ultrasonography is strongly correlated to the no enhancement area by CEUS. The hyperechoic range on gray-scale image can represent the ablated area immediately after MW.