Sick dog
First, cataracts
Cataract refers to an eye disease in which the lens capsule or lens is turbid and the vision is impaired. It can happen to dogs and cats.
Cataract occurred in the left eye of the dog, and the appearance of the eye was cloudy.
Sick dog
Second, the reason
1 congenital cause
Congenital cataract is caused by congenital hypoplasia of lens and its capsule, which is related to heredity and non-heredity. Most canine cataracts are hereditary. Common genetic diseases include retinal hypoplasia and progressive retinal atrophy. Non-genetic factors are related to maternal infection, malnutrition, metabolic disorder and the use of certain drugs. Common in Du Binquan, Song Shi Dog, German Shepherd (details), Beagle Dog, Boston Terrier, Golden Retriever, etc. Congenital cataracts in cats are rare.
2 acquired reasons
Acquired cataract is often secondary to anterior uveitis, retinitis, glaucoma, corneal perforation, anterior lens capsule rupture, long-term X-ray, long-term use of corticosteroids, diabetes and so on. Older animals are prone to cataract due to lens degeneration (especially dogs over 5 years old).
Third, symptoms
Congenital cataract occurs at birth or shortly after birth, mostly bilateral. Adolescent cataract usually occurs in youth, and it often occurs in both eyes.
Eye diagram of sick dog
The lens and its capsule are turbid, and the pupil is discolored.
Ophthalmoscope photograph
Obvious turbidity and white eyes.
Fourth, the pathological process.
There are many reasons for cataract, but whatever the reason, it will increase the permeability of the lens at the onset, make the lens lose its barrier function and lead to lens opacity. There are many ways to classify cataracts, but there are two commonly used methods, that is, according to their different stages, they can be divided into initial stage, immature stage, mature stage and over-mature stage, and according to their pathogenesis, they can be divided into congenital, adolescent, senile, traumatic and complex cataracts.
1 primary cataract
The lens and capsule are partially turbid, which reflects the eyes and has no effect on vision. It accounts for 10%- 15% of the crystal.
2 Infantile cataract
The turbid area of the lens is diffused, but part of the cortex is transparent, and the lens cortex expands, reflecting light, which has certain influence on vision.
Infantile cataract with large lens opacity. Image source (image source (dog's cat's eye scientific color atlas, translated by China Agricultural Science and Technology Publishing House Han Bo)
3 Mature cataract
Cataract infancy chart
The lens is all cloudy and the lens cortex is swollen. Blurred light reflection has obvious influence on vision.
Cataract maturity map
Mature cataract, red eye and corneal edema. Exposure of crystalline protein in cataract lens causes uveitis, and crystalline protein is regarded as a foreign body. Image source (image source (dog's cat's eye scientific color atlas, translated by China Agricultural Science and Technology Publishing House Han Bo)
4. Overmature cataract
Lens atrophy, capsular contraction, cortical liquefaction and decomposition, lens nucleus sinking, blurred light reflection, no vision.
Transitional mature cataract
Over-mature cataract, most of the lens is absorbed, the cortex is completely liquefied, the dense lens sinks into the capsule due to gravity, the lens volume shrinks, the capsule membrane shrinks due to tension, and the capsule bag shrinks. Image source (dog cat's eye scientific color atlas, translated by China Agricultural Science and Technology Publishing House, Han Bo)
Verb (abbreviation of verb) diagnosis
According to the medical history and clinical symptoms, such as whether there is milky white in the depth of the pupil, whether it reflects light, whether the ophthalmoscope can observe the fundus, etc.
Sixth, treatment.
1 drug therapy
At present, there is no ideal drug to treat cataract. It is suggested that selenium, vitamin E, superoxide dismutase, carnosine and zinc citrate should be used locally or systemically to treat cataract. For congenital, infantile or cortical liquefied overdue cataract, mydriatic agents can be used to improve vision. For diabetic cataract, it is helpful to control blood sugar during the rapid water absorption period and before the change of crystallin.
2 surgical treatment
Once the lens cannot be absorbed, surgery should be performed as soon as possible to improve vision without uveitis and normal retina. Surgery includes extracapsular extraction, intracapsular extraction and lens aspiration.
The application of cataract surgery is analyzed according to the specific situation. This article only serves as an understanding of cataract diseases. Please correct me if you understand the deviation. Please follow the doctor's advice for details.