MRI Evaluation of Acute Renal Transplant Dysfunction

描述(由申请人提供)： 肾移植为终末期肾病患者提供了改善的生活质量，使他们免于终生透析及其并发症。大约30%-40%的移植受者至少经历一次急性移植物功能障碍，其中一半经历重复事件。原因包括与血管和输尿管吻合术相关的手术并发症和内在病理，如急性肾小管坏死、排斥反应和药物毒性。现有的监测移植物的方案依赖于不敏感的指标，如血清肌酐，而且临床上很难区分功能障碍的原因，特别是内在疾病。经常需要活组织检查。磁共振成像(MRI)提供了独特的潜力，将移植的解剖评估与使用Gd-DTPA等肾小球造影剂的功能评估相结合。高分辨率Gd增强磁共振肾成像，当使用示踪剂动力学分析时，可以无创地检测和鉴别血管、肾小球和肾小管病变，并通过反映组织病理学的变化，可能使对固有肾脏疾病的准确诊断成为可能。广泛的、长期的目标：通过开发一种可用于监测和诊断移植肾功能障碍的非侵入性测试来提高移植肾的存活率。一项能够准确区分疾病内在原因的测试将确保及时和适当的治疗，并有助于避免侵入性活检程序。 具体目的/方法：(1)确定定量磁共振肾成像的诊断标准，应用血管-肾单位系统示踪动力学模型分析，诊断急性肾移植功能不全患者。(2)开发用于移植肾MR肾成像的半自动图像处理和数据分析方法，使磁共振肾成像在临床上的常规实施成为可能。(3)应用和测试(1)中确定的定量磁共振肾图标准，以诊断急性肾移植功能障碍患者。在其结论中，我们的研究很有可能表明，用于鉴别固有肾脏疾病的功能性磁共振肾成像将是诊断急性肾移植功能障碍的准确工具。

DESCRIPTION (provided by applicant): Renal transplantation affords patients with end stage renal disease an improved quality of life and spares them from life-long dialysis and its complications. Approximately 30-40% of transplant recipients suffer at least one episode of acute graft dysfunction, and half of those experience repeated events. Causes include surgical complications related to vascular and ureteral anastomoses and intrinsic pathology such as acute tubular necrosis, rejection, and drug toxicity. Existing protocols for monitoring grafts rely on insensitive measures such as serum creatinine, and clinical differentiation between causes of dysfunction, particularly intrinsic diseases is difficult. Biopsy is frequently required. Magnetic resonance imaging (MRI) offers the unique potential to combine anatomic evaluation of transplants with a functional assessment using glomerular contrast agents such as Gd- DTPA. High resolution Gd-enhanced MR renography, when interpreted using tracer kinetic analyses, can noninvasively detect and differentiate vascular, glomerular, and tubular pathologies, and by reflecting changes seen at histopathology may enable accurate diagnosis of intrinsic renal diseases. Broad, long-term objectives: To improve renal graft survival by developing a noninvasive test that can be used to monitor and diagnose graft dysfunction. A test that can accurately distinguish intrinsic causes of disease would ensure prompt and appropriate therapy and help to obviate invasive biopsy procedures. Specific Aims/Methods: (1) To determine diagnostic criteria for quantitative MR renography, analyzed using a tracer kinetic model of the vascular-nephron system, to diagnose patients with acute renal transplant dysfunction. (2) To develop semi-automated image processing and data analysis methods for MR renography of renal transplants that will be enable routine clinical implementation of MR renography in the clinical setting. (3) To apply and test quantitative MR renography criteria, as determined in (1), for the diagnosis of patients with acute renal transplant dysfunction. At its conclusion, our study has a high likelihood of showing that functional MR renography for differentiating intrinsic renal diseases, will be an accurate tool for acute renal transplant dysfunction.