Leipzig University Medical Center, IFB Adiposity Diseases, Leipzig, Germany.
University Hospital Leipzig, Department of Medicine, Neurology and Dermatology, Division of Gastroenterology and Rheumatology, Germany.
Ultraschall Med. 2014 Feb;35(1):38-43. doi: 10.1055/s-0033-1356230. Epub 2014 Feb 7.
Spleen elastography is a promising method for the characterization of portal hypertension in cirrhotic individuals. However, standardized examination procedures for spleen stiffness measurement have not been defined yet. We analyzed the distribution characteristics of spleen shear-wave velocity (ARFI) and assessed the influence of the respiratory position on spleen stiffness measured by ARFI.
25 healthy probands and 25 patients with Child A liver cirrhosis were prospectively characterized with conventional ultrasound, transient elastography, liver ARFI, and underwent spleen ARFI in two respiratory positions: breath hold after expiration (exp) and deep inspiration (insp). For each position 20 single measurements were performed. The distribution of spleen ARFI values was analyzed for normality and the appropriate number of measurements for spleen stiffness estimation was investigated.
Spleen ARFI results were normally distributed in > 95 % of cases. Performing 20 instead of 10 single measurements resulted in < 5 % deviation from the mean value after 20 measurements in the majority of cases. Cirrhotic patients had a higher spleen stiffness compared to healthy probands (exp: 3.25 ± 0.58 vs. 2.46 ± 0.35 m/s; p < 0.001). Deep inspiration caused an overall increase in spleen stiffness in both groups: probands 2.46 ± 0.35 m/s (exp) vs. 2.66 ± 0.36 m/s (insp), p = 0.01; cirrhotics 3.25 ± 0.58 m/s (exp) vs. 3.46 ± 0.38 m/s (insp), p = 0.03. However, cases with high spleen stiffness values (exp) show decreasing ARFI values in deep inspiration.
ARFI values of the spleen are normally distributed and the mean of 10 valid measurements can be used as a representative value. Deep inspiration significantly modulates spleen stiffness. Therefore, the respiratory position needs careful standardization.
脾脏弹性成像技术是一种有前途的方法，可用于肝硬化患者的门静脉高压症的特征描述。然而，目前尚未定义脾脏硬度测量的标准化检查程序。我们分析了脾脏剪切波速度（ARFI）的分布特征，并评估了 ARFI 测量时呼吸位置对脾脏硬度的影响。
前瞻性地对 25 名健康志愿者和 25 名 Child A 级肝硬化患者进行常规超声、瞬时弹性成像、肝脏 ARFI 检查，并在两种呼吸位置下进行脾脏 ARFI 检查：呼气末屏气（exp）和深吸气（insp）。每个位置进行 20 次单次测量。分析脾脏 ARFI 值的分布是否符合正态分布，并研究估计脾脏硬度的适当测量次数。
95%的情况下，脾脏 ARFI 结果呈正态分布。在大多数情况下，与 20 次测量的平均值相比，执行 20 次而非 10 次单次测量后，偏差<5%。与健康志愿者相比，肝硬化患者的脾脏硬度更高（exp：3.25±0.58 vs. 2.46±0.35 m/s；p<0.001）。深吸气会引起两组脾脏硬度的整体增加：健康志愿者 2.46±0.35 m/s（exp）与 2.66±0.36 m/s（insp），p=0.01；肝硬化患者 3.25±0.58 m/s（exp）与 3.46±0.38 m/s（insp），p=0.03。然而，具有高脾脏硬度值（exp）的病例在深吸气时显示 ARFI 值降低。
脾脏 ARFI 值呈正态分布，10 次有效测量的平均值可用作代表值。深吸气显著调节脾脏硬度。因此，需要仔细规范呼吸位置。
