Validation of regional ventilation & perfusion and PA02 with a gold standard

描述（由申请人提供）：在正常肺中，肺通气（VA）和灌注(Q)紧密匹配，以优化气体交换效率。各种疾病状态可以改变这种正常关系，并导致异质VA/Q比率不匹配。区域VA/Q和区域氧分压的评估和量化对各种肺部疾病的诊断、评估和治疗至关重要。最近，超极化气体MRI方法被用于研究通气和/或灌注异常。获得肺功能参数的区域图，并研究这些参数在生理缺陷引起的变化。新开发的超极化气体MRI技术克服了与传统放射诊断工具相关的许多困难，并有望全面准确地确定局部肺功能。最近，通过该MRI技术获得的VA/Q数据与核医学进行了比较。然而，这种方法的最终临床应用需要在较小规模的金标准下进行仔细的验证。因此，本提案的主要目标是验证超极化气体MRI技术在局部范围内生成区域通气/灌注比图和肺泡氧分压图的能力。我们假设这些图准确地反映了吸入和注射微球的通气和灌注同时测量的值。为了达到既定目标，将在健康兔模型中使用MRI技术和微球技术获得VA/Q和PAO2的图谱。关键词：极化气体MRI；区域通风;区域灌注;Pegional PAO2

DESCRIPTION (provided by applicant): In a normal lung pulmonary ventilation (VA) and perfusion (Q) are closely matched to optimize the gas exchange efficiency. Various disease states can alter this normal relationship and cause a heterogeneous VA/Q ratio mismatch. The assessment and quantification of regional VA/Q and regional oxygen partial pressure are of paramount importance to the diagnosis, evaluation, and treatment of a variety of pulmonary disorders. Recently, hyperpolarized gas MRI methods have been developed to study ventilation and/or perfusion abnormalities. Regional maps of functional lung parameters were acquired and the changes in these parameters caused by physiologic defects were investigated. The newly developed hyperpolarized gas MRI techniques overcome many of the difficulties associated with traditional radiological diagnostic tools and promises the comprehensive and accurate determination of regional lung function. Recently, VA/Q data obtained by this MRI technique has been compared to nuclear medicine. However, ultimate clinical use of this method demands a careful validation against a gold standard on a smaller scale. Therefore, the main goal of this proposal is to validate the hyperpolarized gas MRI technique for the generation of maps of the regional ventilation/perfusion ratios and maps of the alveolar partial pressure of oxygen on a local scale. We hypothesize that these maps accurately reflect the values obtained from simultaneous measurements of ventilation and perfusion with inhaled and injected microspheres. To achieve the stated goal, maps of VA/Q and PAO2 will be acquired using the MRI technique as well as the microsphere technique in a healthy rabbit model. Key Words: Polarized Gas MRI; Regional Ventilation; Regional Perfusion; Pegional PAO2