脂肪肝為肝臟代謝性能力缺失的初期指標，針對脂肪肝進行診斷與追蹤，能作為嚴重肝臟慢性疾病的警示。肝臟超音波因具有非侵入式與便利性等優點成為最常見的診斷工具。然而，超音波的診斷方式易受限於醫生的主觀意識，因此，許多研究利用半定量法輔助醫生診斷脂肪肝，例如分析肝臟超音波的原始射頻訊號，證實脂肪會改變超音波的聲學特性，或者採用紋理分析辨別脂肪肝的回音特徵，或者以衰減係數描述脂肪肝的嚴重程度等。但目前臨床上仍未有一套完整的標準適用於診斷脂肪肝。
本研究提出結合不同的聲學特性參數以輔助診斷脂肪肝，利用六個紋理特徵參數，即自相關函數、總和平均數、總和變異數、對比、熵及均質性反映脂肪肝超音波影像的各種回音紋理改變，並擷取肝臟超音波的原始射頻訊號，以訊號雜訊比（Signal to noise ratio, SNR）討論脂肪肝的超音波回散射訊號成分，且計算回散射訊號的中心頻率偏移斜率顯示脂肪肝的超音波訊號衰減變化。資料分析共分為兩個階段，第一階段為定量參數的分析能力評估與脂肪肝定量評分標準的制定，其人體資料樣本數共314筆，將診斷效能最好的三個紋理特徵參數以線性判斷分析法統合，並與SNR及中心頻率偏移斜率一起做為脂肪肝定量評分標準的指標，其診斷效率的準確度為72.4%、敏感度為72.2%、特異性為71.8%。第二階段則是驗證臨床使用脂肪肝定量評分標準的能力，其人體資料樣本數共80筆，以隨機取樣的概念進行評估，其診斷效率的準確度為75%、敏感度為71.4%、特異性為77.8%，證實了脂肪肝定量評分標準的可行性。脂肪肝定量評分標準不僅與現行臨床診斷結果有良好的一致性，採取定量的參數也可反映脂肪肝疾病不同的組織特性並排除人為操作的誤差，使結果更加可信。

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78. !!! INVALID CITATION !!!
79. Graif M, Yanuka M, Baraz M, Blank A, Moshkovitz M, Kessler A, Gilat T, Weiss J, Walach E, Amazeen P: Quantitative estimation of attenuation in ultrasound video images: correlation with histology in diffuse liver disease. Invest Radiol 2000, 35(5):319-324.