Department of Medicine, Section of Gastroenterology, Boston University School of Medicine, Boston, Massachusetts, USA.
Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, USA.
Gastrointest Endosc. 2021 Jul;94(1):60-67.e1. doi: 10.1016/j.gie.2020.12.037. Epub 2020 Dec 30.
Portal pressure can be used to identify patients with chronic liver disease who have progressed to cirrhosis. Portal pressure can also provide accurate prognostication for patients with cirrhosis. However, there are no practical means for assessment of portal pressure. Although it is well established that the gastric mucosal blood supply increases in patients with cirrhosis, this has been difficult to quantify reproducibly. Our group has developed a novel spectroscopic technology called spatially resolved subdiffuse reflectance spectroscopy (SRSRS), which enables quantification of mucosal microcirculation. We aim to ascertain if quantification of the gastric mucosal microcirculation with SRSRS correlates with clinical evidence of portal hypertension.
Patients undergoing EGD for clinical indications had 10 measurements taken in the endoscopically normal gastric fundus via SRSRS probe to assess the microcirculation. Cases were defined as patients with cirrhosis (n = 18), and controls were those without evidence of liver disease (n = 18); this was corroborated with transient elastography.
The blood volume fraction (P = .06) and subdiffuse reflectance (P = .02) from a shallow depth in the gastric fundus were higher in patients with cirrhosis than those without. These markers were combined to yield an overall optical marker that can differentiate patients with cirrhosis from controls with a sensitivity of 72% and specificity of 94% (area under receiver operating curve, 0.82).
Spectroscopic quantification of gastric fundal mucosal microcirculation is a promising surrogate of clinical correlates of portal hypertension. This approach may represent a less-intrusive surrogate biomarker for liver disease prognostication and potentially response to therapy.
门静脉压力可用于识别慢性肝病进展为肝硬化的患者。门静脉压力也可以为肝硬化患者提供准确的预后。然而，目前尚无评估门静脉压力的实用方法。尽管已经证实肝硬化患者的胃黏膜血流量增加，但这很难进行可重复的定量。我们的团队开发了一种名为空间分辨漫反射光谱（SRSRS）的新型光谱技术，该技术可实现黏膜微循环的定量。我们旨在确定 SRSRS 定量胃黏膜微循环是否与门静脉高压的临床证据相关。
因临床指征而行内镜检查的患者，通过 SRSRS 探头在内镜正常的胃底进行了 10 次测量，以评估胃黏膜微循环。病例定义为肝硬化患者（n=18），对照组为无肝脏疾病证据的患者（n=18）；这与瞬时弹性成像相吻合。
与无肝硬化的患者相比，肝硬化患者胃底较浅处的血容量分数（P=0.06）和漫反射（P=0.02）更高。这些标志物结合起来产生了一种整体光学标志物，可以将肝硬化患者与对照组区分开来，其敏感性为 72%，特异性为 94%（接收者操作特征曲线下面积，0.82）。
胃底黏膜微循环的光谱定量是门静脉高压临床相关性的有前途的替代指标。这种方法可能代表一种侵入性较小的肝脏疾病预后和潜在治疗反应的替代生物标志物。
