Page 1261 - Problem-Based Feline Medicine

60 – THE CAT WITH ABNORMALITIES CONFINED TO THE CORNEA 1253

There will be a history of herpes keratitis with The cornea develops a ground-glass appearance that
chronic ulceration and scarring of the cornea. is seen as a corneal opacity. This is caused by vacuole
formation in keratocytes and endothelial cells.
This is a rare condition in the cat.
Affected cats usually have neurological signs, which
include ataxia, muscular and head tremors, paralysis
Diagnosis
and hypermetria.
A tentative diagnosis is based on signs of a focal
The retinal ganglion cells and cells in the inner
shiny, gritty lesion on the cornea associated with a
nuclear layer can be affected with vacuole formation.
chronic herpetic keratitis.
Diagnosis
LYSOSOMAL STORAGE DISEASES WITH
OPHTHALMIC MANIFESTATIONS A tentative diagnosis is based on the clinical presen-
tation in a young cat with neurological signs and ocu-
Classical signs lar signs such as corneal opacity.
● A very rare condition in the cat. A definitive diagnosis is made based on histopatho-
● Young cats that develop progressive logical examination of neural tissue using specific
corneal opacity with a “ground glass” staining techniques usually from tissues obtained at
appearance. post mortem. A specialist pathologist will be needed to
● Usually neurological signs such as ataxia, make the diagnosis.
muscular tremor and paralysis.
Lysosomal storage diseases with ophthalmic mani-
festations include:
See the main reference on page 935 for details (The Cat
● GM 1 gangliosidosis.
With Ataxia Without Weakness).
● GM 2 gangliosidosis.
● Alpha mannosidosis.
Clinical signs
● Mucopolysaccharidosis 1 (MPS1).
Signs begin in young cats around 3–6 months of age. ● Mucopolysaccharidosis 2 (MPS2).

RECOMMENDED READING
Barnett KC. A Color Atlas of Veterinary Ophthalmology. Wolfe Publishing Ltd, London, 1990.
Gelatt Kirk N (ed). Veterinary Ophthalmology, 2nd edn. Lea & Febiger, Philadelphia, 1991.
Gelatt Kirk N. Veterinary Ophthalmology, 3rd edn. Lippincott, Williams and Wilkins, Philadelphia, 1998.
Gelatt Kirk N. Essentials of Veterinary Ophthalmology. Lippincott Williams and Wilkins, Philadelphia, 2000.
Gelatt Kirk N. Color Atlas of Veterinary Ophthalmology. Lippincott Williams and Wilkins, Philadelphia, 2001.
Gelatt Kirk N, Gelatt J P. Handbook of Small Animal Ophthalmic Surgery, Vol. 1. Extraocular Procedures. Permagon
Veterinary Handbook Series, Florida, 1994.
Gelatt Kirk N, Gelatt JP. Handbook of Small Animal Ophthalmic Surgery, Vol. 2. Intra-ocular Procedures. Permagon
Veterinary Handbook Series, Florida, 1995.
Ketring KL, Glaze MB. Atlas of Feline Ophthalmology. Trenton, NJ, Veterinary Learning Systems, 1994.
Peiffer RL, Petersen-Jones S. Small Animal Ophthalmology, A Problem Oriented Approach, 3rd edn. Saunders,
Philadelphia, 2001.