Vision Archives - Jack Russell Terrier Research Foundation

Corneal Endothelial Dystrophy/Degeneration

Jan

24

2020

Endothelial Dystrophy – The cornea is normally the transparent “windshield” of the eye, serving to protect the internal structures of the eye while allowing light to enter for vision. The endothelium is a single layer of cells that lines the inside of the cornea. Though only a single cell layer thick, this layer is vital ...

Persistent Pupillary Membranes (PPM)

Jan

24

2020

The pupillary membrane is a fetal structure that covers the pupil prior to birth. It is supposed to resolve (go away) shortly after birth. Sometimes part or all of it will persist. This is known as Persistent Pupillary Membranes (PPM). Most PPMs do not cause significant visual deficit, however some, particularly those that attach to ...

Distichiasis

Jan

24

2020

Distichiasis is a condition where eyelashes emerge from a structure in the eyelid (meibornian gland) which does not normally produce hairs. These “extra eyelashes” emerge so close to the eye that they can contact the ocular surfaces and can cause discomfort and corneal damage. Distichiasis is considered an inherited problem as it is much more ...

Glaucoma

Jan

24

2020

What is Glaucoma and How Does it Develop Glaucoma is a group of neurodegenerative diseases with the most consistent clinical finding being increased intraocular pressure (IOP). Increased IOP is painful and causes damage to the retina and optic nerve, which can rapidly lead to irreversible blindness. Glaucoma is a leading cause of blindness in animals ...

Nutritional Cataracts

Jul

23

2015

By Dr. Lisa Meek, Member ACVO A nutritional cataract is caused by either a deficiency or excess of a nutrient resulting in a loss of transparency of the lens. Nutritional cataracts have been identified in various species, including rats, pigs, wolves, fish and guinea pigs as well as dogs and cats. In dogs and cats ...

Canine Cataracts

Jul

23

2015

Definition of Cataracts The word cataract literally means ‘to break down’. This breakdown refers to the disruption of the normal arrangement of the lens fibers or its capsule, which results in the loss of the transparency of the lens and a reduction in vision. Cataracts often appear to have a white or crushed ice appearance ...

What is Glaucoma?

Jul

16

2015

There are 2 classifications of glaucoma – Primary and Secondary. Primary glaucoma occurs without previous trauma or ocular disease, and will eventually affect both eyes. Secondary glaucoma is a consequence of some other disease, such as ocular inflammation, lens dislocation, intraocular tumors, or trauma. My first reaction was this can’t be primary as the numbers ...

What is Primary Lens Luxation (PLL)?

Jul

16

2015

The canine eye has the same general design as the human eye. Light travels through the cornea, through the watery aqueous chamber, enters the pupil, traverses through the lens, then the vitreous chamber, and finally is absorbed by retinal receptors. The lens is held in place by a network of tiny fibers, called zonules, that ...

Myokymia: Continuous Muscle Fibre Activity

Jul

15

2015

Continuous muscle fibre activity was observed in a crossbred dog, a Yorkshire terrier, a border collie and three Jack Russell terriers. The clinical signs consisted of episodes of generalised myokymia which developed into muscle stiffness and delayed muscle relaxation and generally led to the dogs collapsing into lateral recumbency. These episodes were preceded by intense ...