Real-Time Imaging of Rabbit Retina with Retinal Degeneration by Using Spectral-Domain Optical Coherence Tomography

Abstract

BackgroundRecently, a transgenic rabbit with rhodopsin Pro 347 Leu mutation was generated as a model of retinitis pigmentosa (RP), which is characterized by a gradual loss of vision due to photoreceptor degeneration. The purpose of the current study is to noninvasively visualize and assess time-dependent changes in the retinal structures of a rabbit model of retinal degeneration by using speckle noise-reduced spectral-domain optical coherence tomography (SD-OCT).Methodology/Principal FindingsWild type (WT) and RP rabbits (aged 4–20 weeks) were investigated using SD-OCT. The total retinal thickness in RP rabbits decreased with age. The thickness of the outer nuclear layer (ONL) and between the external limiting membrane and Bruch's membrane (ELM–BM) were reduced in RP rabbits around the visual streak, compared to WT rabbits even at 4 weeks of age, and the differences increased with age. However, inner nuclear layer (INL) thickness in RP rabbits did not differ from that of WT during the observation period. The ganglion cell complex (GCC) thickness in RP rabbits increased near the optic nerve head but not around the visual streak in the later stages of the observation period. Hyper-reflective change was widely observed in the inner segments (IS) and outer segments (OS) of the photoreceptors in the OCT images of RP rabbits. Ultrastructural findings in RP retinas included the appearance of small rhodopsin-containing vesicles scattered in the extracellular space around the photoreceptors.Conclusions/SignificanceIn the current study, SD-OCT provided the pattern of photoreceptor degeneration in RP rabbits and the longitudinal changes in each retinal layer through the evaluation of identical areas over time. The time-dependent changes in the retinal structure of RP rabbits showed regional and time-stage variations. In vivo imaging of RP rabbit retinas by using SD-OCT is a powerful method for characterizing disease dynamics and for assessing the therapeutic effects of experimental interventions.

Novel VCP modulators mitigate major pathologies of rd10, a mouse model of retinitis pigmentosa

“…Total retinal thickness (from inner limiting membrane to Bruch membrane) in rd10 mice was measured using volume scan images33 within a circle 0.366 mm in diameter, the center of which was adjusted to the center of the optic nerve head. The mean value of the upper and lower quadrant was averaged.…”

Cell-based therapeutic strategies for replacement and preservation in retinal degenerative diseases

“…Ophthalmic examinations such as optical coherence tomography (OCT), electroretinography (ERG), and visual acuity testing are able to detect visual function and inner and outer nuclear layer thickness (Berson et al, 1996; Lim et al, 2008). Advances in in vivo imaging systems, such as adaptive optics scanning laser ophthalmoscopy (AOSLO) and spectral domain OCT (SD-OCT), allows for the monitoring of retinal lamination, oxygenation in blood vessels, cellular changes, progression of disease, and response to treatments (Bizheva et al, 2006; Freeman et al, 2010; Holmgren, 1865; Huang et al, 1991; Huber et al, 2009; Kagemann et al., 2007; Muraoka et al, 2012; Novais et al, 2016; Pron, 2014; Srinivasan et al, 2007; Toth et al., 1997; Zayit-Soudry et al, 2013). …”

Novel Endogenous Glycan Therapy for Retinal Diseases: Safety, In Vitro Stability, Ocular Pharmacokinetic Modeling, and Biodistribution

“…An SD-OCT system (Bioptigen Spectral Domain Ophthalmic Imaging System; Bioptigen, Inc., Durham, NC, USA) was used to assess the retinal health post-intravitreal injection in each rabbit at the specified time periods. OCT evaluation allows for noninvasive detection of retinal architecture, including quantitative measurements of retinal thickness and longitudinal observation of the retinal architecture (27). OCT examination demonstrated that the structure of retina was intact and there was no difference in the retina after intravitreal injection.…”