Retinal Vascular Plexuses Are Unequally Affected in Canine Inherited Retinal Degenerations.

Purpose: To characterize the progression of vascular changes that occur in each retinal plexus, in three canine models of inherited retinal degeneration.

Methods: In this retrospective cohort study, we examined the retinal imaging records of 44 dogs from a research colony that had undergone optical coherence tomography angiography (OCTA) imaging. Animals enrolled included crd2/NPHP5 and xlpra2/RPGR mutant dogs imaged at different stages of photoreceptor loss, as well as RHOT4R/+ dogs after acute light-induced rod degeneration.

Targeting ON-bipolar cells by AAV gene therapy stably reverses -congenital stationary night blindness.

SignificanceCanine models of inherited retinal diseases have helped advance adeno-associated virus (AAV)-based gene therapies targeting specific cells in the outer retina for treating blinding diseases in patients. However, therapeutic targeting of diseases such as congenital stationary night blindness (CSNB) that exhibit defects in ON-bipolar cells (ON-BCs) of the midretina remains underdeveloped. Using a leucine-rich repeat, immunoglobulin-like and transmembrane domain 3 () mutant canine model of CSNB exhibiting ON-BC dysfunction, we tested the ability of cell-specific AAV capsids and promotors to specifically target ON-BCs for gene delivery.

Novel insights into chorioretinal and juxtapapillary colobomas by optical coherence tomography.

Purpose: The purpose was to describe the in vivo microanatomy of typical and atypical chorioretinal and juxtapapillary colobomas in the dog.

Methods: Three cross-breed dogs were found to be affected with colobomas. Two of the cases were NEHJ1 homozygous and Collie Eye Anomaly (CEA) affected and had the typical optic nerve head colobomas seen with the disease.

Monocular retinopathy of prematurity-like retinal vasculopathy in a dog.

Purpose: To describe a case of monocular retinopathy of prematurity (ROP)-like vasculopathy without oxygen supplementation in the dog.

Methods: Fundus photographs (RetCam), spectral-domain optical coherence tomography (sdOCT), confocal scanning laser ophthalmoscopy (cSLO), and fluorescein angiography (FA), as well as postmortem histology and immunohistochemistry (Collagen IV and anti-vWF antibodies), were carried out to characterize the vascular abnormalities.

Results: Ophthalmic examination showed peripheral and mid-temporal avascular areas in the tapetal region, neovascularization and abnormally dilated and tortuous retinal vessels in the left eye.