The cat cataract is an ophthalmic condition less common than in dogs, but one that can significantly affect the quality of life of your senior feline. Contrary to what many owners believe, lens opacity in elderly cats is not always a cataract: it is often nuclear sclerosis, a normal ageing process of the eye that requires no treatment. According to international veterinary studies, only 5–10% of cats develop true cataracts during their lifetime, with a higher incidence after the age of 10.
What is a cataract in cats and how to recognise it
Feline cataract involves the clouding of the lens, the eye's natural focusing element. This opacity prevents light from reaching the retina correctly, causing progressive visual impairment. Unlike in dogs, where cataracts are often hereditary and bilateral, in cats the causes are predominantly acquired and linked to systemic conditions.
The difference between cataracts and nuclear sclerosis
Nuclear sclerosis is the main "false alarm" for owners of elderly cats. It is a physiological hardening of the lens nucleus that gives the eye a bluish-grey appearance, visible from as early as 6–7 years of age. This process does not significantly impair vision and requires no intervention. True cat cataract, on the other hand, appears as a white or milky opacity, often asymmetrical, and progresses causing blindness. A veterinary ophthalmologist can distinguish between the two conditions using a slit-lamp examination and ophthalmoscopy.
Stages of feline cataract development
Cataracts in cats are classified into four progressive stages:
- Incipient: minimal opacity, less than 10% of the lens affected, vision preserved
- Immature: partial opacity (10–99%), onset of visual impairment, pupillary reflex still present
- Mature: complete opacity, functional blindness, lens still intact
- Hypermature: degradation of lens proteins, possible phacoclastic uveitis (severe inflammation)
According to ACVO (American College of Veterinary Ophthalmologists) guidelines, surgical intervention is ideally scheduled at the immature or early mature stage, before inflammatory complications arise.
Symptoms to watch for in your cat
Cats compensate remarkably well for visual impairment thanks to their other senses, making early diagnosis difficult. Pay attention to these signs:
- Hesitation when jumping or misjudging distances
- Increased vocalisation, especially in unfamiliar environments
- Dilated pupils even in good lighting conditions
- Visible opacity in the eye, often more noticeable with side lighting
- More cautious behaviour or reluctance to move in the dark
Main causes of cataracts in cats
Unlike genetically predisposed dog breeds, cat cataract almost always has a secondary origin related to systemic conditions or ocular trauma. Identifying the underlying cause is essential for the prognosis and treatment plan.
Feline diabetes mellitus
Diabetes is the most common cause of acquired cataract in cats, present in 15–20% of diabetic patients according to retrospective studies. Chronic hyperglycaemia causes sorbitol to accumulate in the lens, drawing in water by osmosis and causing swelling and clouding of the lens fibres. Diabetic cataracts in cats progress more slowly than in dogs (weeks to months vs. days to weeks), but can still reach the mature stage within 6–12 months without adequate glycaemic control. The average monthly cost of managing feline diabetes in Italy ranges from €80 to €150, including insulin, syringes and monitoring.
Systemic hypertension
Arterial hypertension, often secondary to chronic kidney disease or hyperthyroidism, can cause retinal detachment, intraocular haemorrhages and secondary cataract. Approximately 60% of cats with chronic kidney disease develop hypertension, and of these 5–8% may present with ocular complications including cataract. Regular blood pressure monitoring (every 3–6 months) in senior cats is recommended by ISFM (International Society of Feline Medicine) guidelines.
Other causes of feline cataract
Additional aetiological factors include:
- Ocular trauma: perforations, severe contusions, penetrating foreign bodies
- Chronic uveitis: persistent inflammation caused by FIV, FeLV, toxoplasmosis, FIP
- Nutritional deficiencies: extremely rare with balanced commercial diets, but possible with inadequate home-prepared diets
- Toxicity: exposure to radiation, medications (prolonged corticosteroids)
- Congenital: extremely rare, documented in Persians, Burmese and Himalayans
Diagnosing cataracts in cats
A definitive diagnosis of cat cataract requires a full specialist ophthalmic examination. Never rely solely on observation at home: many eye conditions can mimic the appearance of a cataract.
Complete ophthalmic examination
The veterinary ophthalmologist performs a structured assessment that includes:
- Schirmer tear test: evaluates tear production (normal 15–25 mm/min in cats)
- Fluorescein staining: highlights corneal ulcers that could complicate surgery
- Tonometry: measures intraocular pressure (normal 10–25 mmHg)
- Biomicroscopy: detailed examination with a slit lamp to pinpoint the exact location of the opacity
- Indirect ophthalmoscopy: assesses the retina and optic nerve (essential for post-surgical visual prognosis)
The cost of a specialist ophthalmic consultation in Italy ranges from €80 to €150, with an additional €50–100 for advanced diagnostic procedures such as ocular ultrasound.
Necessary supporting tests
Before any surgical procedure, systemic tests are essential to identify underlying conditions and assess anaesthetic risk:
- Full biochemical profile (kidney and liver function, blood glucose)
- Complete blood count
- Thyroid profile (total T4) in cats over 7 years of age
- Blood pressure measurement
- Complete urinalysis
- FIV/FeLV serology
The complete pre-surgical package costs an average of €150–250 at Italian veterinary clinics.
Surgical treatment: phacoemulsification
The only definitive treatment for cataracts in cats is surgical removal of the clouded lens by phacoemulsification, followed where appropriate by implantation of an artificial intraocular lens (IOL). There are no eye drops or medical therapies capable of dissolving or reversing a cataract.
How the procedure works
Phacoemulsification uses ultrasound to break up and emulsify the clouded lens, which is then aspirated through a 2–3 mm corneal micro-incision. The procedure involves:
- General anaesthesia (higher risk in cats than in dogs due to sensitivity to anaesthetic agents)
- Minimal corneal incision
- Anterior capsulotomy (opening the capsule containing the lens)
- Phacoemulsification of the nucleus and aspiration of the cortex
- Optional IOL implantation (less common in cats than in dogs)
- Corneal suturing with absorbable material
The average duration is 45–90 minutes per eye. The success rate in cats is 80–90% according to veterinary literature, slightly lower than in dogs due to the greater postoperative inflammatory reactivity of the feline species.
Cost of cataract surgery
The cost of phacoemulsification in cats in Italy varies considerably:
- Unilateral procedure: €1,200–2,000
- Bilateral procedure: €2,000–3,500
- IOL implantation: +€300–500 per eye
- Hospitalisation and follow-up: €200–400
University ophthalmology centres may offer slightly lower fees (€900–1,500 per eye). Bear in mind that the cost includes pre-operative tests, anaesthesia, surgery, materials, hospitalisation and at least 2–3 post-operative check-ups.
Post-operative care and prognosis
The post-surgical period is critical and requires:
- Antibiotic and anti-inflammatory eye drops 3–4 times a day for 4–6 weeks
- An Elizabethan collar for 10–14 days (essential: cats scratch easily)
- Restricted physical activity for 2 weeks
- Ophthalmic check-ups at 1, 7, 14 and 30 days, then every 3–6 months
Possible complications include postoperative uveitis (20–30% of cases, manageable with medication), secondary glaucoma (5–10%) and retinal detachment (rare, 2–3%). Without IOL implantation, the cat becomes hyperopic (+12–15 dioptres) but regains functional vision for daily life thanks to depth of field and the other senses.
Preventing cataracts in cats
Although not all forms of cat cataract are preventable, you can significantly reduce the risk with strategies focused on your feline's systemic and ocular health.
Managing predisposing conditions
Optimal management of diabetes, hypertension and kidney disease is the most effective form of prevention:
- Diabetes: keeping blood glucose below 200 mg/dl reduces the risk of cataract by 60–70% according to prospective studies
- Hypertension: target systolic blood pressure below 160 mmHg, monitored every 3–6 months in at-risk cats
- Kidney disease: specific renal diet, phosphorus control, adequate hydration
Regular veterinary check-ups (every 6 months after the age of 7, every 3–4 months after the age of 10) allow early diagnosis and timely management of these conditions. You can find more information on managing feline diabetes in our dedicated article on diabetes in cats.
Nutrition and antioxidant support
A balanced diet meeting AAFCO or FEDIAF standards provides all the nutrients necessary for ocular health. Certain nutrients have shown protective potential:
- Vitamin E: an antioxidant that protects the cell membranes of the lens
- Lutein and zeaxanthin: carotenoids with a protective effect on the retina and lens
- Omega-3s (EPA/DHA): systemic and ocular anti-inflammatory properties
- Taurine: an essential amino acid for cats, fundamental for the retina and lens
Choose premium commercial foods that explicitly declare the inclusion of these nutrients. The average cost of high-quality dry food for senior cats is €4–8/kg. For further guidance on food choices, see our guide on cat dry food.
Protection from trauma and toxins
Reduce environmental risks:
- Supervise outdoor access or consider keeping senior cats indoors
- Remove toxic plants and accessible chemical products
- Avoid prolonged use of corticosteroids without veterinary supervision
- Protect your cat from stressful situations that could trigger self-harming behaviour
Managing a cat with inoperable cataracts
Not all cats are ideal surgical candidates due to advanced age, serious concurrent conditions or high anaesthetic risk. In these cases, you can significantly improve quality of life with environmental adaptations.
Adapting the home environment
Cats adapt exceptionally well to partial or total blindness thanks to their hearing, sense of smell and whiskers:
- Keep the arrangement of furniture, litter tray and bowls consistent
- Use rugs with different textures to mark specific areas (litter tray entrance, feeding area)
- Install low-intensity night lights in corridors
- Block access to stairs, balconies and pools with physical barriers
- Enrich the environment with olfactory and auditory stimuli (catnip, sound-making toys)
Monitoring for complications
Hypermature cataracts can cause phacoclastic uveitis, secondary glaucoma and eye pain. Check regularly for:
- Persistent eye redness
- Excessive tearing or discharge
- Squinting or an eye that appears larger
- Signs of pain: keeping the eye half-closed, rubbing with the paw, reduced activity
If you notice any of these symptoms, contact your vet immediately. Palliative medical therapy with anti-inflammatory eye drops can control inflammation and preserve comfort, even without visual recovery.
Frequently asked questions
Are cataracts painful for cats?
Cataracts themselves do not cause pain, but their complications can. At the hypermature stage, degraded lens proteins can leak out and trigger phacoclastic uveitis, a severe inflammation that causes intense pain, redness and potential secondary glaucoma. This condition requires urgent treatment with topical and systemic anti-inflammatory medications. If you notice your cat keeping its eye half-closed, rubbing it frequently or showing redness, contact your vet straight away.
How quickly do cataracts progress in cats?
Progression varies enormously depending on the cause. Diabetic cataracts can advance from incipient to mature in 6–12 months without adequate glycaemic control. Traumatic cataracts may stabilise after several months or progress slowly. Idiopathic senile forms tend to progress very slowly, sometimes over years. Only regular ophthalmic monitoring (every 3–6 months) makes it possible to assess the specific rate of progression in your cat and plan any intervention at the optimal time.
Can my cat live well without surgery?
Absolutely. Cats compensate for vision loss far better than dogs, thanks to their highly developed senses and excellent spatial memory. Many owners do not even realise their cat has gone blind until they rearrange the furniture. With minimal environmental adaptations (keeping the position of objects, litter tray and bowls consistent), cats with mature bilateral cataracts live fully satisfying lives. Surgery is mainly recommended when the cataract is unilateral or at an early stage, to preserve remaining vision, or when painful complications arise.
Are there eye drops or supplements that treat cataracts?
No, there are no scientifically validated medical therapies capable of dissolving, reducing or reversing cataracts in cats. "Anti-cataract" eye drops available on the market (often containing N-acetylcarnosine) have not demonstrated efficacy in controlled animal studies and are considered to have no therapeutic value by the leading international veterinary ophthalmological societies. Antioxidant supplements may theoretically play a preventive role by slowing oxidative processes, but they do not reverse opacities that have already formed. The only definitive treatment remains surgical removal of the clouded lens by phacoemulsification.
Cat cataract requires a personalised approach based on age, general health, stage of the condition and the owner's expectations. Early diagnosis through regular ophthalmic check-ups in senior cats, and optimal management of predisposing systemic conditions, are the most effective strategies for preserving your feline's visual health. Whether you choose surgery or conservative management, your cat can continue to enjoy an excellent quality of life with the right care and attention.
