Overhauser Enhanced Magnetic Resonance Imaging (OMRI)

A)利用体内低场中水的超极化，根据肿瘤的血管渗透性和氧合作用来描述肿瘤。超极化通常是用顺磁分子进行的。从图像强度分布中，我们同时获得了肿瘤氧气和肿瘤血管通透性，并与肿瘤的免疫组织化学特征相关。我们发现肿瘤缺氧与肿瘤血管通透性增加有关，而肿瘤血管通透性与血管周细胞覆盖率呈负相关。B)监测超极化(体外)13C标记的丙酮酸在肿瘤中的体内分解产物：在本研究中，我们注射13C标记的丙酮酸并监测其向乳酸的转化。肿瘤中丙酮酸/乳酸比值被量化，并与EPRI获得的肿瘤血氧图相关联。

a) Profile tumors in terms of tumor vascular permeability and oxygenation using in vivo hyperpolarization of water at low fields. Hyperpolarization is usually carried out with the paramagnetic molecule TAM. From the image intensity profiles we obtained tumor oxygen and tumor vascular permeability simultaneously and correlated with immunohistochemical characterization of tumors. We found that tumor hypoxia was associated with increased tumor vascular permeability which in turn was negatively correlated with vascular pericyte coverage. b) Monitor the in vivo breakdown products of hyperpolarized (ex vivo) 13C-labeled pyruvic acid in tumors: In this study, we injected 13C labeled pyruvate and monitored the conversion to lactate. The pyruvate/lactate ratio was quantified in the tumor and correlated with oxygen maps from the tumor obtained from EPRI.