Retinotopic Imaging of the Central Visual Pathway in Optic Nerve and Outer Retinal Disease

Abstract

Purpose : Retinal pathology and resulting vision loss can lead to structural and functional alterations in the brain. The changes that take place in the central visual pathway have implications for sight-restoring treatments targeting the retina, but are poorly understood in the context of varying disease entities. In particular, optic neuropathies which result in inner retinal abnormalities may induce unique structural and functional changes in the brain compared to outer retinal disease due to the robust topographic organization of the inner retinal layers. Here, we study a representative sample of patients with non-arteritic anterior ischemic neuropathy (NAION), an optic nerve process, along with macular dystrophy, an outer retinal disease.

Methods : Subjects were recruited as part of our 4-year NIH-funded study and underwent retinal imaging and microperimetry assessment, as well as multimodal MRI imaging using the Human Connectomes Project protocol. The retinotopic organization between points along the central visual pathway and the retina allows brain measurements to be displayed on the same coordinates as a fundus image. Retinotopic coordinates for cortical areas V1-V3 were determined by fitting a deformable template to digital reconstruction of a patient’s cortex derived from T1-weighted MRI data.

Results : We present on 2 patients with outer retinal disease (juvenile macular dystrophy) and 5 patients with optic nerve disease (NAION). Co-registration of data allowed for the visualization of blue-laser auto-fluorescence images, microperimetry, and fMRI cortical response to be compared to one another in fundus coordinates. In both groups, regions of retinal pathology and microperimetric field loss corresponded with decreased fMRI V1 cortical BOLD response.

Conclusions : Utilizing high-definition retinal and neuroimaging techniques, the relationship between pathology in different layers of the retina and resulting downstream alterations in the brain can be elucidated with exceptional detail. Our preliminary data set suggests that optic neuropathy and outer retinal disease differ in their functional and structural implications along the CVP.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.

 

Ex. of outer retina disease (macular dystrophy) vs optic nerve disease (NAION). Areas of negative V1 cortical response correlated with retinal areas of complete scotoma in a subject with juvenile macular dystrophy, while the NAION subject did not show such a relationship.