MRI of Diabetic Retinopathy

糖尿病视网膜病变的 MRI

• 批准号: 10391756
• 负责人: Timothy Q. Duong
• 金额: $ 15.82万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10391756
• 关键词: MRI; Diabetic; Retinopathy

Diabetic retinopathy (DR) is the leading cause of blindness in working-age adults and occurs in about 45% of diabetic patients. DR is often diagnosed by late manifestations of the disease, such as blurred vision and abnormal appearance of the fundus. By the time a clinical diagnosis is made, vision loss or blindness is often the inevitable outcome. Results from clinical trials have documented that strict glycemic control in the early stages of diabetes is effective in reducing the risk of DR. Thus, early identification of diabetic individuals who are at risk of DR will enable timely intervention to minimize the risk of vision loss. The retina consists of three major cell layers (photoreceptor, bipolar, and ganglion) and two vascular (retinal and choroidal) layers bounding the retina, each of which is affected differently by DR. Our laboratory has pioneered innovative layer-specific blood-flow and functional MRI techniques based on echo-planar imaging at ~80x80x1000 µm. Echo-planar imaging of the eye suffers from susceptibility artifacts and image blurring, which precludes the earliest and most reliable DR detection. Moreover, although fluorescein angiography is widely used for visualization of vessels and diagnosis of DR, it does not have layer resolution and fluorescein (an optical contrast agent) can cause severe negative reactions, especially in diabetics who often have compromised renal function. Alternative approaches that can provide vascular layer resolution without needing a contrast agent will also have important clinical significance. We have recently explored non-echo-planar imaging approaches to study the retina. Our preliminary data show that balanced steady-state free precession (bSSFP) MRI provides markedly improved image quality and spatial resolution for blood-flow and functional MRI, and that MR angiography (MRA) provides layer-specific retinal and choroid vessels in the rat retina without using a contrast agent. In this proposal, we aim: i) to further develop bSSFP and MRA methods to study the rat retina with laminar specificity without using a contrast agent, ii) to evaluate these approaches to detect the earliest changes in retina of streptozotocin-induced diabetes, and iii) to test the hypothesis that strict glycemic control reverses these very early pre-vision loss manifestations of retinal changes in diabetes. Our central hypothesis is that abnormal retinal and choroidal blood flow and neurovascular coupling in the early pre-clinical stage of retinal changes in diabetes are detectable by these novel MRI methods prior to anatomic changes, and are reversed by strict glycemic control.

糖尿病性视网膜病（DR）是劳动年龄成年人失明的主要原因，发生在大约 45％的糖尿病患者。 DR通常是通过疾病的晚期表现来诊断的，例如视力模糊 眼底异常外观。到进行临床诊断时，视力丧失或失明为 通常不可避免的结果。临床试验的结果证明，严格的血糖控制 糖尿病的早期阶段可有效降低DR的风险。那，糖尿病患者的早期识别 有DR风险的人将及时干预以最大程度地减少视力丧失的风险。 视网膜由三个主要细胞层（感光器，双极和神经节）和两个血管组成 （视网膜和脉络膜）层结合视网膜的层，每个视网膜都受到DR的影响。我们的实验室 是否开创了基于回声平面的创新层特异性血液和功能性MRI技术 〜80x80x1000 µm成像。眼睛的回声平面成像受到敏感性和图像的易感性 模糊，这排除了最早，最可靠的DR检测。而且，虽然荧光素 血管造影广泛用于可视化血管和DR的诊断，它没有层分辨率 荧光素（一种光学造影剂）会引起严重的负面反应，尤其是在糖尿病患者中 通常会损害肾功能。可以提供血管层分辨率的替代方法 不需要对比剂也将具有重要的临床意义。 我们最近探索了研究视网膜的非回声平面成像方法。我们的初步数据 证明平衡的稳态无预防预防（BSSFP）MRI可显着提高图像质量和 血流和功能性MRI的空间分辨率，MR血管造影（MRA）提供了特定层的特定层 大鼠视网膜中的视网膜和脉络膜vissels不使用造影剂。在此提案中，我们的目标是：i）进一步 开发BSSFP和MRA方法，以层流特异性研究大鼠视网膜，而无需使用对比度 代理，ii）评估这些方法以检测链蛋白酶诱导的视网膜最早变化 糖尿病和iii）测试了严格血糖控制的假设，可逆转这些早期的易见前损失 糖尿病残留变化的表现。我们的中心假设是视网膜和脉络膜异常 在糖尿病的永久性变化的早期临床前阶段的血流和神经血管耦合为 在解剖学变化之前可以通过这些新型MRI方法检测，并通过严格的血糖控制逆转。