Simultaneous Multiwavelength Imaging of Retinal Nerve Fiber Layer for Early Diagnosis of Glaucoma

University Of Miami, Coral Gables FL

Investigators

Abstract

Glaucoma is a leading cause of blindness worldwide. Early diagnosis can permit early medical intervention to prevent irreversible visual loss caused by damage to the retina. To assess the glaucoma damage, non-contact optical measurement of retina layer thickness is typically performed in clinical practice. The available optical measurement technique is, however, not sensitive enough to assess early signs of glaucomatous damage of the retina. Recent laboratory studies show that the ultrastructure of the retina is damaged first before apparent retina thickness change. The ultrastructure damage causes reflectance decreases at different wavelengths as disease progresses. Unfortunately, there is no available optical modality that can assess the retina spectral reflectance in real time. This project will design and construct such an imaging device. Completion of the project will lead to a new non-contact optical method that can sensitively detect early glaucoma damage. The study will find the relationship between retina spectral reflectance changes and glaucoma damage by using a rat model of glaucoma. The gained knowledge will have significant impact to the early diagnosis of glaucoma and related medical treatment monitoring. The proposed research will benefit academic research and education by providing graduate students with multidisciplinary training in biophotonics, microelectromechanical systems, and imaging, and by supporting undergraduate senior projects and summer research experiences. The goals of this project are to design, construct, and explore a novel fundus multiwavelength imaging modality for in vivo simultaneous multiwavelength imaging of the retinal nerve fiber layer (RNFL) and to provide a thorough understanding of in vivo measurement of the RNFL reflectance spectrum. The work builds on the investigators' in vitro experiments that concluded that (1) in the glaucomatous retinas RNFL reflectance decreases prior to thinning of the RNFL and (2) the decrease of RNFL reflectance occurs early at visible wavelength and later at infrared wavelength. The research plan is organized under three specific aims: (1) Design, construct, and explore a new fundus multiwavelength imaging device; (2) Validate measurement capability of the fundus multiwavelength imaging device by comparing the reflectance spectra of the same RNFL measured in vivo and in vitro in the normal rat retina; and (3) Study RNFL reflectance spectra in retinas with glaucoma damage by using a rat model of glaucoma. The gained knowledge will have significant impact on the early diagnosis of glaucoma, which will prevent irreversible visual loss caused by retinal damage, and related medical treatment monitoring. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.