Fighting like cats and dogs! Eye scratch injuries are most common in young puppies
Puppies are particularly susceptible to traumatic eye injuries from cat scratches as it takes some time, usually 3 months, for puppies to learn to blink rapidly in response to a threatening (or menacing) movement such as a cat claw. Eye scratch injuries in puppies are often seen in the ophthalmology referral hospital. It is young puppies that are most commonly affected, usually not long after arriving in their new homes and meeting the cat of the house.
What damage can be caused by a cat scratch to a dog or puppy’s eye?
Eye scratch injuries in puppies and dogs can vary from a simple skin wound to a perforating injury to the eye. Dog owners should always examine their dog if there are any signs of a possible argument with a cat (if they have heard hissing of the cat, screaming of the puppy/dog etc). In cases of eye trauma the affected eye is often painful, closed and watering a lot. Most of the time your dog will not allow you to examine the eye as it is so painful.
Forcing an examination or trying to flush an acutely traumatised eye is not recommended as the eye may be leaking or a very fragile eye may rupture in the process of this, making the damage even worse.
If the dog keeps the eye shut, they should always be examined by a veterinary surgeon to assess the severity of the trauma and the possible need for further treatment. As with most conditions, rapid recognition of the problem and early treatment of eye scratch injuries increases the chance of recovery.
What can my vet do for an eye scratch injury in my puppy?
Fig 1: This swollen, sore eye was the result of a cat scratch. The loose flap of tissue on the surface of the eye moves with every lid movement and prevents healing of the eye scratch injury.
Your vet will be able to use painkillers and/or use a sedative or even an anaesthetic to allow the safe examination of the eye. They may use local anaesthetic eye drops to numb the surface of the eye so that a closer examination is possible without distressing the patient further.
The initial examination usually reveals whether or not the surface of the eye has been damaged and if a referral to an ophthalmologist is needed. This will be the case whenever surgical repair of a wound may be required, as this has to be done under an ‘operating microscope’ to allow sufficient magnification of the very delicate tissue.
Fig 2: This puppy has an eye scratch injury. There is damage to the surface of the eye and blood in the front chamber.
Cat scratch injuries may damage the clear window of the eye, called the cornea. Even in case of a non-perforating injury, a tissue flap may be created by the trauma (Fig 1). A corneal flap will be manipulated by every eyelid movement, which is very painful for the patient and will also inhibit healing of the wound. In case of a perforating injury – when the cat claw injury has actually opened up the cavity of the eye – the consequences for the eye may be even more serious. Inner structures of the eye such as the iris and the lens may be traumatised. The iris may protrude out of the eye and there may be bleeding inside the eye (Fig 2). If the lens has been damaged, the patients will also develop a cataract (an opacity of the lens) and with it usually severe inflammation inside they eye (uveitis).
What are the treatment options for eye scratch injuries in puppies and dogs?
Fig 3: This is the same dog with an eye scratch injury as in Fig 1. The loose tissue flap has been removed and the healing of the wound is progressing well (the green area is actually a dye which has been put into the eye during the examination).
Treatment options will depend on the extent of the injury. In case of a simple skin wound a painkiller with or without a systemic antibiotic may be sufficient. Corneal flaps either have to be removed (Fig 3) or sutured back in place. Either way, simple corneal wounds tend to heal well.
Fig 4: This is the same puppy with an eye scratch injury as in Fig 2. The wound has been stitched and the blood removed from the inside of the eye. He is also wearing a contact lens to reduce the irritation of the stitches. The contact lens can be identified by the black dot on its surface.
The placement of a bandage like contact lens may improve the comfort of the patient further (Fig 4). More complex surgical techniques are required if the inner structures of the eye have been damaged. Iris tissue may have to be pushed back into the eye or parts of it may have to be removed. In case of a lens injury the lens may have to be removed. Sometimes the eye can be so severely damaged that it will remain blind and removal of the eye may be the kindest option for the patient.
Painkillers are used to keep the patients comfortable and antibiotics will help to treat a likely infection. Patients should also wear a buster collar to prevent any self-induced trauma due to discomfort or itchiness of the healing eye.
What is the outlook for the damaged eye following a scratch injury?
Depending on the severity of the trauma, patients may just be left with a scar in the cornea. However, if structures inside the eye have been damaged, then vision is likely to remain impaired, and blinding complications may occur even years after the initial injury.
Eye scratch injuries from cats are best avoided. Dog owners should keep young puppies and cats separated from each other for at least the first 3-4 months, as this is the time when the puppies do not yet have a normal blink response to a threatening movement. Cat scratch injuries can of course occur in older dogs and may also affect cats, but the risk is very much increased and the damage is often more severe in young puppies.
About Claudia Busse
Claudia graduated from the School of Veterinary Medicine, Hanover, in 2004. She initially worked in general practice in Germany, while completing her doctoral thesis on hereditary eye disease at the School of Veterinary Medicine in Hanover. She moved to England in 2005 to undertake an internship at the Animal Health Trust, followed by a Residency training programme, becoming a Diplomate of the European College of Veterinary Ophthalmologists in 2010. She has worked as a clinician in veterinary ophthalmology since then.