Wie erkenne ich Katarakt beim Hund?

Milchig-weiße oder grau-weiße Linsentrübung im direkten Licht. Sehverschlechterung: Orientierungsprobleme, Stolpern, Zögern. Nukleäre Sklerose sieht ähnlich aus, beeinträchtigt das Sehen aber kaum. Differenzierung durch Tierarzt.

Kann Katarakt beim Hund behandelt werden?

Ja — durch Phakoemulsifikation (Ultraschallzertrümmerung der Linse + Kunstlinse). Erfolgsrate über 90% bei früh-operierten Patienten mit gesunder Netzhaut. Voraussetzung: Elektroretinogramm vor der OP.

Muss ein Hund mit Katarakt immer operiert werden?

Nicht zwingend. Einseitiger Katarakt mit gutem Sehen am anderen Auge kann beobachtet werden. OP-Indikation: beidseitiger Katarakt, signifikante Sehverschlechterung, junger Hund, diabetischer Katarakt. Entscheidung individuell mit Ophthalmologen.

Health & Diseases

Cataracts in Dogs: Symptoms, Causes & Treatment

A cataract is an opacification of the eye's lens that impairs a dog's vision or, in cases of complete opacification, leads to blindness. The lens, which is normally transparent, loses its clarity due to altered protein structures. Cataracts are the most common treatable cause of blindness in dogs.

Auf einen Blick

A cataract is an opacification of the eye's lens that impairs a dog's vision or, in cases of complete opacification, leads to blindness. The lens, which is normally transparent, loses its clarity due to altered protein structures. Cataracts are the most common treatable cause of blindness in dogs.
Risiko-Hinweis: low-moderate: Consider context and individual differences
Wissenschaftliche Einordnung: Davidson and Nelms (2013, Veterinary Ophthalmology, Wiley-Blackwell) describe canine cataract forms by cause: Hereditary cataract is the most common form in dogs and documented in numerous breeds. Diabetic cataract develops in dogs with diabetes mellitus in 80% of cases within 6 months of diagnosis due to osmotic lens swelling. Traumatic cataract occurs after eye injuries. Age-related (senile) cataract is less common in dogs than in humans but does occur in older dogs.Gelatt et al. (2003, Veterinary Ophthalmology, PubMed 14738502) analyzed the prevalence of breed-specific cataracts: Boston Terriers, Siberian Huskies, American Cocker Spaniels, Welsh Springer Spaniels, Miniature and Toy Poodles, Labrador Retrievers, and Bichon Frisés are particularly commonly affected. Genetic tests for cataract predispositions are recommended for breeding animals of these breeds. Breeding screening by the respective breed associations reduces the incidence of hereditary cataracts.Sigle and Nasisse (2006, JAVMA, PubMed 16426193) analyzed long-term complications after phacoemulsification (cataract surgery) in 172 dogs: The surgical success rate (functional vision postoperatively) was over 90% in early-operated cases. Complications (lens capsule opacification, retinal detachment, glaucoma) occurred in some cases; pre-operative screening (electroretinogram to rule out retinal disease) is crucial for patient selection.

Cataracts in dogs: symptoms, causes & treatment

What is a cataract in dogs?

A cataract is a clouding of the eye’s lens that impairs a dog’s vision or — if the clouding is complete — leads to blindness. The lens, which is normally transparent, loses its transparency due to altered protein structures. Cataract is the most common treatable cause of blindness in dogs.

Important: Cloudy eyes in an older dog are not automatically cataracts. Nuclear sclerosis — an age-related, blue-gray clouding of the lens — barely affects vision and is not a cataract. Differentiation requires an ophthalmological examination.

Background + scientific context

Davidson and Nelms (2013, Veterinary Ophthalmology, Wiley-Blackwell) describe forms of cataract in dogs according to cause: Hereditary cataract is the most common form in dogs and is documented in numerous breeds. Diabetic cataract develops in dogs with diabetes mellitus in 80% of cases within 6 months after diagnosis — due to osmotic swelling of the lens. Traumatic cataract occurs after eye injuries. Age-related (senile) cataract is less common in dogs than in humans, but it does occur in older dogs.

Gelatt et al. (2003, Veterinary Ophthalmology, PubMed 14738502) analyzed the prevalence of breed-specific cataracts: Boston Terriers, Siberian Huskies, American Cocker Spaniels, Welsh Springer Spaniels, Miniature and Toy Poodles, Labrador Retrievers, and Bichon Frisés are particularly commonly affected. Genetic testing for cataract predisposition is recommended for breeding animals of these breeds. Rearing-stage screening by the relevant breed associations reduces the incidence of hereditary cataracts.

Sigle and Nasisse (2006, JAVMA, PubMed 16426193) analyzed long-term complications after phacoemulsification (cataract surgery) in 172 dogs: The surgical success rate (functional vision postoperatively) was over 90% in cases operated on early. Complications (lens capsule opacification, retinal detachment, glaucoma) occurred in some cases; preoperative screening (electroretinogram to rule out retinal disease) is essential for patient selection.

Vitomalia position

Cataracts in dogs are treatable — and deciding for or against surgery is not trivial. Early diagnosis and ophthalmologic assessment increase the chances of a good surgical outcome. Waiting until complete blindness worsens the prognosis: hypermature cataract lenses increase the risk of inflammation and the complexity of surgery.

When does cataract become relevant?

With milky-white or blue clouding of the lens: veterinary examination to distinguish cataract from nuclear sclerosis
With known diabetes mellitus: regular eye checks (80% develop cataracts)
For breeds with genetic predisposition: ophthalmologic screening by the breeder
When visible deterioration in vision occurs (orientation problems, stumbling, hesitation in the dark)
For breeding dogs: DNA tests for cataract mutations before breeding

Practical application

Cataract types and consequences:

Type	Cause	Treatment approach
Hereditary	Genetic, breed-specific	Surgery for clinically significant clouding
Diabetic	Diabetes mellitus	First regulate diabetes, then surgical evaluation
Traumatic	Eye injury	Individual assessment
Nuclear sclerosis (not a cataract!)	Age-related, harmless	No treatment needed
Secondary (uveitis, glaucoma)	Other eye disease	Treat the underlying disease

Diagnostic steps: 1. Ophthalmologic examination (biomicroscopy, fundus) 2. Electroretinogram (ERG): assess retinal function before surgery 3. Intraocular pressure measurement: rule out glaucoma 4. Blood count, glucose: diabetes screening

Common mistakes & myths

“My old dog’s cloudy eyes are cataracts.” Nuclear sclerosis is an age-related, harmless clouding of the lens without significant visual impairment — and it is not a cataract. Differentiation should be made by a veterinarian.
“I’ll wait with surgery until my dog is truly blind.” Hypermature cataract lenses can release lytic material and cause inflammation (phacogenic uveitis). Early surgery has a better prognosis.
“Eye surgery in dogs is too risky.” With appropriate patient selection and in specialized centers, phacoemulsification is an established procedure with a functional success rate of over 90%.

Scientific status 2026

Phacoemulsification is the gold standard in cataract surgery for dogs — an equivalent technique to that used in human ophthalmology. Genetic markers for hereditary cataract variants are being identified in more and more breeds; DNA tests are available for many breeds. Diabetic cataracts remain a particular challenge because their rapid progression makes timely surgical planning more difficult.

Frequently asked questions

How can I recognize cataracts in dogs?

Milky-white or gray-white clouding of the eye lens, visible in direct light. Changed vision: orientation problems, stumbling, hesitation on steps or in the dark. Note: nuclear sclerosis looks similar but hardly affects vision. Differentiation by a veterinarian using an ophthalmoscope.

Can cataracts in dogs be treated?

Yes — through phacoemulsification (ultrasonic fragmentation of the clouded lens and implantation of an artificial lens). Success rate over 90% in patients operated on early with a healthy retina. Requirement: electroretinogram before surgery to rule out retinal disease.

Does a dog with cataracts always need surgery?

Not necessarily. A unilateral cataract with good vision in the other eye can be monitored. Indications for surgery: bilateral cataract, significant deterioration in vision, young dog, diabetic cataract (rapid progression). The decision should be discussed individually with an ophthalmologist.

Related terms

Sources & further reading

Davidson, M. G., & Nelms, S. R. (2013). Diseases of the lens and cataract formation. In K. N. Gelatt, B. C. Gilger, & T. J. Kern (Eds.), Veterinary Ophthalmology (5th ed., pp. 1199–1233). Wiley-Blackwell. ISBN 9780813812250.
Gelatt, K. N., & MacKay, E. O. (2003). Prevalence of primary breed-related cataracts in the dog. Veterinary Ophthalmology, 8(2), 101–111. https://pubmed.ncbi.nlm.nih.gov/14738502/
Sigle, K. J., & Nasisse, M. P. (2006). Long-term complications after phacoemulsification for cataract removal in dogs: 172 cases (1995–2002). Journal of the American Veterinary Medical Association, 228(1), 74–79. https://pubmed.ncbi.nlm.nih.gov/16426193/

Wissenschaftliche Einordnung

Davidson and Nelms (2013, Veterinary Ophthalmology, Wiley-Blackwell) describe canine cataract forms by cause: Hereditary cataract is the most common form in dogs and documented in numerous breeds. Diabetic cataract develops in dogs with diabetes mellitus in 80% of cases within 6 months of diagnosis due to osmotic lens swelling. Traumatic cataract occurs after eye injuries. Age-related (senile) cataract is less common in dogs than in humans but does occur in older dogs.

Gelatt et al. (2003, Veterinary Ophthalmology, PubMed 14738502) analyzed the prevalence of breed-specific cataracts: Boston Terriers, Siberian Huskies, American Cocker Spaniels, Welsh Springer Spaniels, Miniature and Toy Poodles, Labrador Retrievers, and Bichon Frisés are particularly commonly affected. Genetic tests for cataract predispositions are recommended for breeding animals of these breeds. Breeding screening by the respective breed associations reduces the incidence of hereditary cataracts.

Sigle and Nasisse (2006, JAVMA, PubMed 16426193) analyzed long-term complications after phacoemulsification (cataract surgery) in 172 dogs: The surgical success rate (functional vision postoperatively) was over 90% in early-operated cases. Complications (lens capsule opacification, retinal detachment, glaucoma) occurred in some cases; pre-operative screening (electroretinogram to rule out retinal disease) is crucial for patient selection.