結果と考察：非狭窄群29例（39%），狭窄群61例（56%）で胸部症状を認めた．狭窄群のEAT厚は，非狭窄群に比べ有意に大であった（8.3±2.8 vs. 5.7±2.1 mm, p＜0.001）．ROC解析では，EAT厚＞7.0 mmをカットオフ値とすると感度67%，特異度78%で糖尿病患者の有意狭窄が診断できた．さらに，従来の冠危険因子に胸部症状の有無を加えてもArea under the carve（AUC）の増加は有意でなかったが，EAT厚を加えるとAUCは有意に増加した（AUC: 0.65 vs. 0.82, p＜0.001）．このことから，EAT厚は従来の冠危険因子や胸部症状に加えて冠動脈有意狭窄予測における付加的価値があることが示された．
対象と方法：対象は，日本超音波医学会認定の超音波検査士資格（消化器領域）を取得している8名とした．方法は，ベッドが座面と同じ高さを基準とし，±5 cm, ±10 cmの5段階の高さについて評価した．人体模型に対して指定したプロトコル（①：右肋骨弓下走査～肋間走査，②：右側腹部走査，③：左側腹部走査）で走査を行い，その間の筋電図，身体角，探触子の操作性について測定した．測定筋は右尺側手根屈筋，右橈側手根伸筋，右僧帽筋，右菱形筋とした．身体角は，体幹角についてビデオ画像と加速度計で，右肩拳上角についてはビデオ画像のみで測定した．探触子の操作性については，右手背に加速度計を装着し計測した．
In this session, clinical laboratory data, conventional US and US elastography for diagnosing NAFLD/NASH were discussed after having lectures of basic concept and pathological diagnosis of NAFLD/NASH. Following descriptions of below are highlights of this session.
NAFLD has been categorized as one of metabolic syndrome of the liver, which diagnosed as fatty liver by imaging modalities and hepatic biopsy except alcoholic fatty liver diseases. NAFLD is classified into NAFL and NASH. NASH progresses to liver cirrhosis after 20 years, and developing HCC after 5 to 10 years. NAFLD/NASH will be increasing rapidly as underlying condition of LC and HCC in the near future, so that taking some measures are matters of great urgency. Pathologically, NASH is defined by more than 5% fat deposition, infiltrating inflammation cells into lobules hepatitis and ballooning degeneration. Especially ballooning degeneration, fibrosis and Mallory-Denk body are important findings relating to hepatocellular injury and progressive disease.
NAFLD should be enclosed by performing US once for metabolic syndrome patients, further diagnosis of NASH can be made by combination of more than two markers such as NAFLD fibrosis score, NAFIC score, FIB-4 index and platelet counts. The diagnostic criteria proposed by Japanese Society of Gastroenterology of NAFLD are bright liver, hepato-renal contrast, deep attenuation and vascular blurring. Good measurement precision and reproducibility of US elastography were presented. Attenuation parameter which can presume amount of fat deposition in the liver, measured by FibroScan® and general use US system are well correlated to Hounsfield Unit of CT and Alanine transaminase. High elasticity (12 kPa＜), low CAP level (260 dB/m＞) and complication of DM are possible high risk group of HCC. Fatty liver findings of B mode US are well correlated to pathological diagnosis. US elasticity measured in NBNC patients tended to estrange from pathological diagnosis (less than 10%). Fibrosis can be more accurately diagnosed by elastography than B mode US.
In closing this session, recognizing NAFLD/NASH are national disease is important, performing US to pick up fatty liver in metabolic syndrome patients, further estimation of laboratory data and US elastography can make enclosing liver fibrosis. Clinical laboratory team and clinicians should cooperated closely in enclosing high risk patients in daily practice of NAFLD/NASH.