DOI: 10.3179/jjmu. JJMU.A.37 ◇ ORIGINAL ARTICLE ◇ 肝左葉内側区域萎縮に注目した C 型肝炎における B モードでの新たな肝線維化評価法塩屋晋吾林尚美平賀真雄佐々木崇橋口正史坂口右己川村健人中村克也大久保友紀重田浩一朗抄　録目的：慢性肝疾患で最も初期に起こる形態変化として肝左葉内側区域（S 4）の萎縮が報告されている．B モード画像により C 型慢性肝炎患者の S 4 の萎縮を評価し，FibroScan®（以下，FS）による肝線維化指標との比較を行った．対象と方法：対象は C 型慢性肝疾患で腹部超音波検査と FS を同日に施行した 52 例．S 4 形態は，門脈左枝横行部 - S 4 辺縁間距離（以下，S 4 距離）で評価した．肝線維化は，FS の Stiffness の中央値を gold standard として判断した．S 4 距離と Stiffness，各血液検査データ，脾腫との相関を検討した．結果：S 4 距離を FS における肝線維化 staging 毎に評価すると F 0，F 1，F 2，F 3，F 4 では平均 4. 0 mm，4. 2 mm，7. 6 mm，7. 9 mm，9. 5 mm と長くなり，F 0 と F 2・F 3・F 4 間，F 1 と F 2・F 3・F 4 間に有意差を認めた．Cut off 値を 5. 6 mm とすると F 2 以上は sensitivity 91. 3％，speciﬁcity 80. 0％で区別できた．S 4 距離と各血液検査データとの間に相関を認めた．脾腫との間には相関は認めなかった．結語：S 4 距離での肝線維化評価は，簡易的かつ客観的肝線維化 staging の新しい評価法の 1 つとなり得ることが示唆された．特に，F 1 以下と F 2 以上を高率に検出できる点で臨床的に有用な手段と考える． A new method of estimation of liver fibrosis in chronic hepatitis C using B-mode ultrasonography focusing on atrophy of the internal segment of the left lobe Shingo SHIOYA, RMS, Masao HIRAGA, RMS, Masafumi HASHIGUCHI, Kento KAWAMURA, Yuki OOKUBO, RMS, Naomi HAYASHI, RMS, Takashi SASAKI, RMS, Yuuki SAKAGUCHI, RMS, Katsuya NAKAMURA, RMS, Kouichirou SHIGETA, SJSUM Abstract Purpose : Atrophy of the internal segment of the left hepatic lobe（S 4）has been reported as the ﬁrst morphological change in chronic liver disease. S 4 atrophy was evaluated by B-mode ultrasound, and the results were compared with liver ﬁbrosis index estimated by FibroScan（FS）. Material and Method : Fifty-two cases with hepatitis C were examined with abdominal ultrasonography and FS on the same day that they were enrolled. S 4 atrophy was evaluated by the distance between the transverse portion of the portal vein and the edge of the S 4（S 4 distance）. Liver ﬁbrosis was determined as the median of the stiffness on FS as the gold standard. The correlation between S 4 distance and stiffness, each blood test date, and spleen index were assessed. Results : The S 4 distance became longer with progression of liver ﬁbrosis, i.e., 4. 0, 4. 2, 7. 6, 7. 9, and 9. 5 mm（mean）for F 0, F 1, F 2, F 3, and F 4, respectively. There were signiﬁcant differences between F 0 and F 2, F 0 and F 3, F 0 and F 4, F 1 and F 2, F 1 and F 3, and F 1 and F 4. At a cut-off value of 5. 6 mm, it was possible to distinguish F 2 or higher with a sensitivity of 91. 3％ and a speciﬁcity of 80. 0％. There was a signiﬁcant correlation between the S 4 distance and each blood test data, but not the spleen index. Conclusion : Our ﬁndings suggested that S 4 distance could serve as a new index for easily and objectively staging hepatic ﬁbrosis. In particular, it was a clinically useful tool in that it could detect ﬁbrosis F 2. Keywords chronic hepatitis C, ﬁbrosis, B-mode, FibroScan, stiffness 霧島市立医師会医療センター Kirishima City Medical Association Medical Center, 3320 Matsunaga, Hayato, Kirishima, Kagoshima 899︲5112, Japan Received on October 28, 2014; Rivision accepted on March 20, 2015 J-STAGE. Advanced published. date: May 7, 2015 Jpn J Med Ultrasonics