Snapshot Retinal Imaging Mueller Matrix Polarimeter

快照视网膜成像 Mueller 矩阵旋光计

• 批准号: 8772768
• 负责人: Michael Kudenov
• 金额: $ 19.84万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8772768
• 关键词: Algorithms; Animal Model; Area; Arizona; Atrophic; Biological Preservation; Birefringence; California; Clinic; Clinical Sensitivity; Clinical Trials; Complex; Data Set; Defect; Detection; Devices; Diagnosis; Disease; Early Diagnosis; Early Intervention; Early treatment; Eye; Fiber; Fundus; Glaucoma; Health; Human; Image; Imagery; Imaging technology; Institutes; Lasers; Light; Measurement; Measures; Mechanics; Modality; Modeling; Morphologic artifacts; Motion; Neighborhoods; North Carolina; Ophthalmoscopy; Optic Disk; Optical Coherence Tomography; Optics; Oryctolagus cuniculus; Pathologic; Patients; Performance; Property; Public Health; Research; Research Project Grants; Resolution; Retina; Retinal; Scanning; Science; Sensitivity and Specificity; Software Engineering; Structure; Surgeon; Symptoms; System; Technology; Testing; Thick; Time; Universities; Vision; Visual Fields; Visual impairment; base; college; comparative; cost; cost effective; design; experience; image registration; imaging modality; improved; instrument; novel; polarimetry; prototype; retinal nerve fiber layer; screening; two-dimensional

DESCRIPTION (provided by applicant): Worldwide, over 65 million people suffer visual impairment from glaucoma. Because the vast majority of patients rarely experience symptoms of glaucoma until relatively late in the disease, early diagnosis and treatment is essential in preserving vision. Currently, the diagnosis of glaucoma is based on a combination of structural optic disc changes and functional visual field changes. Unfortunately, both of these tests are relatively subjective and definitive diagnosis of glaucoma can be delayed or missed as a result. However, it is well accepted that defects in the retinal nerve fiber layer (RNFL; i.e. structural changes) precede the onset of visual field loss by as much as six years. A number of imaging methods including confocal scanning laser ophthalmoscopy (cSLO), optical coherence tomography (OCT) and scanning laser polarimetry (SLP) have been developed to allow early detection of these subtle structural defects. Of these, SLP provides promise in achieving the earliest detection of glaucoma-induced retinal changes. However, since SLP is not a complete polarimeter, its measurements are prone to error due to the RNFL's diattenuation and depolarization. Thus, accuracy of the SLP's retardance distribution is influenced by the unknown retinal diattenuation and depolarization, decreasing the device's sensitivity and specificity. Furthermore, commercial SLPs only image small sections of the retina in the neighborhood of the optic nerve head, suffer from motion artifacts, and are expensive (estimated cost of $17k using commercial off-the-shelf (COTS) parts and mechanical scanners). We have overcome these limitations with a less expensive (estimated $10k using COTS parts), complete Mueller matrix (MM) polarimeter with no moving parts: the Snapshot Retinal Imaging Mueller Matrix (SRIMM) polarimeter. This device avoids temporal scanning and allows a real-time measurement of the retina's complete polarization state over a large field of view. This device has several advantages. First, the device's cost reduction may make it a more practical and cost-effective instrument for screening patients. Second, since the design has no temporal scanning, large retinal areas can be observed, in a single fundus snapshot, without the need for complex image registration algorithms. Third, the ability to acquire a complete MM data set with high temporal resolution will improve the clinical sensitivity and specificity of this device by removing measurement errors related to depolarization and diattenuation. This is a collaborative effort between North Carolina State University, USC Eye Institute, and the University of Arizona. The specific aims are 1. Design, calibrate, validate and test a fundus camera prototype of a Snapshot Retinal Imaging Mueller Matrix (SRIMM) polarimeter. 2. Design and build a model eye to characterize and validate the performance of the polarimeter. 3. Validate the SRIMM polarimeter's performance in a rabbit model and in a limited number of human patients via comparative measurements taken with a high-resolution SD-OCT and a Zeiss GDx.

描述（由申请人提供）：全世界有超过 6500 万人因青光眼而患有视力障碍。由于绝大多数患者直到疾病相对晚期才出现青光眼症状，因此早期诊断和治疗对于保持视力至关重要。目前，青光眼的诊断是基于结构性视盘变化和功能性视野变化的结合。不幸的是，这两种测试都相对主观，因此可能会延迟或错过青光眼的明确诊断。然而，人们普遍认为，视网膜神经纤维层（RNFL；即结构变化）的缺陷早于视野丧失的六年。现已开发出多种成像方法，包括共焦扫描激光检眼镜 (cSLO)、光学相干断层扫描 (OCT) 和扫描激光偏振测定法 (SLP)，以便及早发现这些细微的结构缺陷。其中，SLP 有望尽早检测青光眼引起的视网膜变化。然而，由于SLP不是一个完整的旋光计，由于RNFL的衰减和去极化，其测量很容易出现误差。因此，SLP 延迟分布的准确性受到未知视网膜衰减和去极化的影响，从而降低了设备的灵敏度和特异性。此外，商业 SLP 只能对视神经乳头附近视网膜的小部分进行成像，存在运动伪影，而且价格昂贵（使用商业现成 (COTS) 部件和机械扫描仪的估计成本为 17,000 美元）。我们通过更便宜（使用 COTS 部件估计为 10,000 美元）、无移动部件的完整 Mueller 矩阵 (MM) 旋光计克服了这些限制：快照视网膜成像 Mueller 矩阵 (SRIMM) 旋光计。该设备避免了时间扫描，并允许在大视场内实时测量视网膜的完整偏振状态。该设备有几个优点。首先，该设备成本的降低可能使其成为一种更实用且更具成本效益的患者筛查工具。其次，由于该设计没有时间扫描，因此可以在单个眼底快照中观察大的视网膜区域，而不需要复杂的图像配准算法。第三，获取具有高时间分辨率的完整MM数据集的能力将通过消除与去极化和衰减相关的测量误差来提高该设备的临床灵敏度和特异性。这是北卡罗来纳州立大学、南加州大学眼科研究所和亚利桑那大学之间的合作成果。具体目标是 1. 设计、校准、验证和测试快照视网膜成像 Mueller 矩阵 (SRIMM) 旋光计的眼底相机原型。 2. 设计并构建模型眼来表征和验证旋光计的性能。 3. 通过使用高分辨率 SD-OCT 和 Zeiss GDx 进行的比较测量，验证 SRIMM 旋光计在兔子模型和有限数量的人类患者中的性能。