Evaluation of Focal Hepatic Lesions on Tissue Harmonic Imaging and Conventional Sonography Along with Histopathological Correlation

Abstract

Background: Focal hepatic lesions span a wide spectrum from benign incidental findings to aggressive malignancies, and accurate characterisation is essential for management. Conventional grayscale ultrasonography is the usual first-line modality but is limited by artefacts, low signal-to-noise ratio and poor margin delineation. Tissue harmonic imaging (THI) reconstructs images from harmonic signals generated within tissue, potentially improving image quality. This study compared THI with conventional ultrasonography and assessed its diagnostic performance against histopathology. Materials and Methods: In this prospective observational study, 80 patients with focal hepatic lesions underwent paired conventional ultrasonography and THI. Lesion conspicuity, margin definition, artefact burden, signal-to-noise ratio, posterior acoustic enhancement, fluid–solid differentiation and overall image quality were graded on an ordinal scale by two observers. Imaging was correlated with histopathology obtained by fine-needle aspiration cytology or biopsy. Paired image-quality scores were compared using the Wilcoxon signed-rank test. Results: The cohort was predominantly elderly (mean age 62.5 years) and male (67.5%), with multifocal, right-lobe, hypoechoic or heterogeneously hypoechoic lesions predominating. Metastatic disease (47.5%) and hepatocellular carcinoma (38.8%) were the commonest diagnoses. THI was significantly superior for lesion conspicuity, margin definition, artefact suppression, signal-to-noise ratio, posterior acoustic enhancement, fluid–solid differentiation and overall image quality (p < 0.05). Against histopathology, THI showed a sensitivity of 85.5%, specificity of 77.8%, positive predictive value of 93.0%, negative predictive value of 60.9% and accuracy of 83.8% (area under the curve 0.816). Conclusion: Tissue harmonic imaging significantly improves image quality and diagnostic confidence over conventional ultrasonography and should be routinely incorporated into hepatic ultrasound protocols. Key words: Tissue harmonic imaging, Conventional ultrasonography, Focal hepatic lesions, Image quality, Hepatocellular carcinoma, Liver metastases.