Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA.
AJR Am J Roentgenol. 2011 Jul;197(1):64-70. doi: 10.2214/AJR.10.5989.
MR elastography (MRE) is an MRI-based technique for quantitatively assessing tissue stiffness by studying shear wave propagation through tissue. The goal of this study was to test the hypothesis that hepatic MRE performed before and after a meal will result in a postprandial increase in hepatic stiffness among patients with hepatic fibrosis because of transiently increased portal pressure.
Twenty healthy volunteers and 25 patients with biopsyproven hepatic fibrosis were evaluated. Preprandial MRE measurements were performed after overnight fasting. A liquid test meal was administered, and 30 minutes later a postprandial MRE acquisition was performed. Identical imaging parameters and analysis regions of interest were used for pre- and postprandial acquisitions.
The results in the 20 subjects without liver disease showed a mean stiffness change of 0.16 ± 0.20 kPa (range, -0.12 to 0.78 kPa) or 8.08% ± 10.33% (range, -5.36% to 41.7%). The hepatic stiffness obtained in the 25 patients with hepatic fibrosis showed a statistically significant increase in postprandial liver stiffness, with mean augmentation of 0.89 ± 0.96 kPa (range, 0.17-4.15 kPa) or 21.24% ± 14.98% (range, 7.69%-63.3%).
MRE-assessed hepatic stiffness elevation in patients with chronic liver disease has two major components: a static component reflecting structural change or fibrosis and a dynamic component reflecting portal pressure that can increase after a meal. These findings will provide motivation for further studies to determine the potential value of assessing postprandial hepatic stiffness augmentation for predicting the progression of fibrotic disease and the development of portal hypertension. The technique may also provide new insights into the natural history and pathophysiology of chronic liver disease.
磁共振弹性成像(MRE)是一种基于 MRI 的技术,通过研究剪切波在组织中的传播来定量评估组织硬度。本研究旨在验证以下假设:由于门静脉压力短暂升高,肝纤维化患者在餐前和餐后进行 MRE 检查会导致肝硬度的餐后增加。
对 20 名健康志愿者和 25 名经肝活检证实为肝纤维化的患者进行了评估。在隔夜禁食后进行餐前 MRE 测量。给予液体试验餐,30 分钟后进行餐后 MRE 采集。使用相同的成像参数和感兴趣区分析来进行餐前和餐后采集。
在 20 名无肝病的受试者中,结果显示平均硬度变化为 0.16±0.20kPa(范围:-0.12 至 0.78kPa)或 8.08%±10.33%(范围:-5.36%至 41.7%)。在 25 名肝纤维化患者中,肝硬度的餐后肝硬度明显增加,平均增加 0.89±0.96kPa(范围:0.17-4.15kPa)或 21.24%±14.98%(范围:7.69%-63.3%)。
慢性肝病患者 MRE 评估的肝硬度升高有两个主要组成部分:反映结构变化或纤维化的静态成分和反映门静脉压力的动态成分,餐后压力可能会升高。这些发现将为进一步研究提供动力,以确定评估餐后肝硬度增加对预测纤维性病进展和门静脉高压发展的潜在价值。该技术还可能为慢性肝病的自然史和病理生理学提供新的见解。