Acoustic structure quantification (ASQ): a new tool in sonographic examination of liver lesions in hepatic alveolar echinococcosis.

Purpose: Qualitative and quantitative acoustic structure quantification (ASQ) is a new, noninvasive sonographic imaging method based on B-mode. This prospective clinical pilot study aims to answer the question whether delineation and measurement of liver lesions in hepatic alveolar echinococcosis (HAE) can be improved by ASQ. Furthermore, this is the first pilot study to explore how ASQ parameters in HAE lesions develop.

Methods: A total of 24 patients (male = 13/female = 11, mean age = 52 years (16-85), mean disease duration = 68 months (1-334)) with HAE were examined with ASQ using a Toshiba Aplio 500 unit. ASQ parameters were measured in HAE liver lesions and in adjacent non-tumor parenchyma. Quantitative analysis was performed offline using ASQ quantification software.

Results: Subjectively parasitic tumors in HAE appear more prominent in color-coded ASQ imaging, but the size of lesions measured in ASQ mode does not differ from size measurements in B-mode. Median focal disturbance ratio (FD ratio) in lesions was 3 (0.1-3), compared with 0.5 (0.1-1.8) in surrounding liver parenchyma (p < 0.0001). Statistical comparison of other ASQ parameters (mode, average, standard deviation) shows results that are similarly significant with p values between p < 0.0001 and p < 0.0018.

Conclusion: ASQ is a promising sonographic method for examination and quantification of structural changes of liver parenchyma in HAE lesions.