(E-167) Detection of retinal structural change in XBP1-knockout mice with vis-OCT

Introduction:

Early detection of diabetic retinopathy in its early development is imperative to early treatment and higher chances of preventing vision loss in patients suffering from diabetes. With the use of visible-light optical coherence tomography (vis-OCT) we can generate a high-resolution 3D image to visualize detailed retinal structure changes, which will aid in the early detection of this disease.




Materials and Methods:

In this study, we used a home-built balance detection vis-OCT system to image mice with X-box binding protein 1 (XBP1) knock out. It has been shown that the loss of XBP1 leads to accelerated retinal neuron degeneration and retinal function decline in mouse models of Type I diabetes.

The images were acquired following the temporal speckle averaging protocols, where each image volume consists of 512 A-lines and 512 B-scans, with each B-scan repeated twice and each volume repeated five times. The images were reconstructed following the methods in and vis-OCT fibergraphy and angiography were then generated. Next, we used MATLAB to analyze their retinal nerve fiber layer (RNFL) by measuring fiber bundle sizes and retinal blood vessel density (VD). The results were then compared with those from the wildtype mice retina images.




Results, Conclusions, and Discussions:

Comparing with those from wildtype mice, we found a decrease in the retinal nerve fiber bundle size and a decrease in retinal vessel density. In wildtype mice we found an average area size of the retinal nerve fiber bundle of 280.93µm, compared to the XBP1 knockout mice which averaged 206.59 µm. We also found on average that retinal vessel density averaged 27.05% where the XBP-1 mice averaged 24.57%.

Vis-OCT was able to detect early signs of diabetic retinopathy by observing both the retinal vessel density and size of the retinal nerve fiber bundle. Moving forward, larger testing groups should be researched to assure the data found is replicable. Testing on model organisms with similar ocular structure to humans should follow.




Acknowledgements (Optional):



References (Optional):
McLaughlin T, Siddiqi M, Wang JJ, Zhang SX. Loss of XBP1 Leads to Early-Onset Retinal Neurodegeneration in a Mouse Model of Type I Diabetes. J Clin Med. 2019;8(6):906. Published 2019 Jun 25. doi:10.3390/jcm8060906

David Miller, Marta Grannonico, Mingna Liu, Elise Savier, Kara McHaney, Alev Erisir, Peter Netland, Xiaorong Liu, and Hao F. Zhang, "Visible-light optical coherence tomography fibergraphy of the tree shrew retinal ganglion cell axon bundles," bioRxiv (2023)

https://tvst.arvojournals.org/article.aspx?articleid=2770901