Ocular (Eye) Trauma in Small Mammals

Ocular trauma is the result of blunt or sharp forces inflicted directly to the eye. Blunt injuries to the eye are sustained when flat or blunt objects strike the surface of the eye and are more often associated with major eye damage than sharp trauma. These concussive forces can result in proptosis of the eye, which is forward displacement or bulging of the eye from the bony eye socket (orbit), lens luxation (displacement), hyphema (bleeding within the front chamber of the eye), retinal detachment, and rupture with collapse of the eyeball (globe).

Sharp injuries occur when piercing, pointed or jagged objects forcefully connect with the eye. Common examples include cat claw injuries, thorns, branches, umbrella points, writing instruments, or small airborne objects. Potential injuries include laceration of the eyelids, surface abrasion, laceration or perforation (rupture) of the cornea, hyphema, lens displacement or lens capsule tear with cataract formation. Sharp ocular injuries are less often associated with explosive globe rupture and loss of intraocular contents.

Ocular trauma can affect pets of any age. Younger animals are more likely to act without caution around cats capable of inflicting claw injuries. They are also more likely to stray from their owners and become injured by other animals or be involved in road accidents. Outdoor cats are more prone to ocular trauma and are also more likely to encounter other unrestrained or wild animals and vehicles. Non-neutered male cats are more prone to roaming and are at a higher risk for traumatic injuries.

What to Watch For

• Increased blinking, squinting and tearing
• Eye redness
• Corneal surface cloudiness
• Minor bleeding from the eye or eyelids
• Evidence of reduced vision.
• Signs of extreme pain
• Closed and squinted eyelids
• Increased eye discharge (tearing, mucous strands or bleeding)
• Significant color changes of the eye such as cornea cloudiness and increased redness on the surface or within the eye.
• Significant bleeding within the eye may obstruct the pupil entirely, resulting in blindness.

Diagnosis

Veterinary care should include diagnostic tests to determine the severity and extent of the injuries that were sustained by the eye and to determine subsequent treatment.

There are several potential diagnostic tests. Recommendations depend upon the likelihood of the potential diagnosis, the species and cost concerns. These tests may include:

• Physical examination and history. This should include examination for evidence of head injuries, swellings and fractures of the skull, bony orbit, nose (nasal sinuses), and jaw. Animals with evidence of major ocular trauma must be evaluated for concurrent injuries that may be life threatening or that require immediate stabilization, such as the respiratory or cardiovascular systems. Historically, it is important to determine whether the trauma was blunt or sharp in nature and if the injuries presented are recent (acute) or chronic. This information often helps to determine prognosis.
• Complete ophthalmic examination. This should include slit-lamp biomicroscopy, which is a magnified view of the front chamber of the eye, and direct and indirect ophthalmoscopy, which is a magnified view of the posterior cavity of the eye and retina.
• Cytology and culture of cell samples collected from corneal injuries
• Fluorescein stain testing to evaluate for the presence of corneal abrasions or ulcers and lacerations
• Neurologic examination to assess for the presence of neurologic injury in animals with head trauma
• Skull radiographs (x-rays) to determine the presence of bony orbital, nasal or jaw fractures
• Ultrasound examination of the eye to evaluate for the presence of lens displacement, retinal detachment and globe rupture

Treatment

Treatment depends on the extent and severity of the ocular injuries. There is no "general" treatment for this symptom. Treatment may involve either medical, or medical and surgical intervention to stabilize the ocular injuries.

Home Care

Seeking immediate veterinary medical attention is critical as many forms of ocular trauma are vision threatening and most are associated with significant discomfort or pain.

Keep your pet quiet and confined to a safe area in order to minimize further injury if vision appears to be impaired. Do not allow him to rub excessively or traumatize the injured eyes. A protective collar called an Elizabethan collar may be necessary to ensure this and may be obtained from your veterinarian.

Proptosed globes are eyes traumatically displaced from their sockets and should be lubricated with a moist clean cloth or K-Y jelly during transport to the hospital to prevent the eye from becoming dry or injured further.

Do not administer human over-the-counter medicines such as Visine® or other ophthalmic products designed to 'reduce eye redness' or irritation as the extent of the injury must be identified and appropriately treated.

Preventive Care

Gently clean away any eye discharge with a warm moist cloth as needed until the cause of the problem is identified. Do not allow your pet to rub or traumatize the eyes.

Do not delay in bringing your pet to the hospital for examination as some causes of excessive ocular discharge are potentially vision threatening and require immediate medical attention.