Table 1:

High-priority research topics towards the better understanding of canine glaucoma disease mechanisms.

Canine ocular anatomy and physiology

Characterization of:

Anterior chamber anatomy and dimensions. Aqueous humor dynamics, including estimation of conventional and unconventional outflow, by measurement of episcleral venous pressure, tonography and fluorophotometry. Aqueous humor outflow pathway structure and function. Effect of gender, breed, and age on anatomy and physiology of the anterior segment, including aqueous humor outflow pathways.

Pathogenesis of elevated IOP in canine breed-specific, primary glaucoma

Description of (including potential age-effect):

Genetic risk factors. Role of anterior chamber depth. Location of increased outflow resistance, including segmental variations. Role of pectinate ligament and pectinate ligament dysplasia and its relationship with ciliary cleft width. Width of ciliary cleft at different disease stages and forms of disease, including segmental variations. Role of iris volume, shape (‘plateau iris’), and pupillary block in iridocorneal angle closure. Effect of lens, including size and position, and lens zonules on aqueous humor outflow pathways, especially ciliary cleft. Role of episcleral venous pressure. Role of uveoscleral outflow. Role of inflammation. Role of pigment dispersion. Altered scleral biomechanics (stiffness) on aqueous humor outflow, including width of ciliary cleft and posterior uveoscleral outflow. Role of angular aqueous plexus. Role of choroidal thickness changes, including pulsatile component.

Pathogenesis of canine optic nerve head and retinal degeneration

Investigation of:

Pathogenesis of tapetal sparing (less retinal atrophy superior vs. inferior). Role of abnormal ocular perfusion.

Pathogenesis of post-phacoemulsification glaucoma

Improve our understanding of:

Risk factors and differences to other species, including human. Role of inflammation and use of anti-inflammatory drugs Effect of globe size. Effect of pectinate ligament dysplasia. Changes in ciliary cleft and lens zonule tension following cataract surgery. Role of surgeon experience. Possible correlation with post-operative hypertension. Effect of intraocular lens and capsular tension ring on ciliary cleft width and glaucoma development. Factors contributing to pre-iridal fibrovascular membrane (PIFVM) formation and its role in secondary glaucoma development.