Clinical Symptoms of Canine “Cherry Eye”

Canine “cherry eye,” a common ailment particularly affecting small, long-haired breeds, is characterized by the protrusion or eversion of the nictitating membrane gland from the inner corner of the eye. This results in a noticeable, reddish mass resembling a cherry, hence the name. This article will detail the clinical symptoms of this condition, offering a comprehensive understanding for owners and veterinary professionals alike.

Early Stage Symptoms:

The initial stages of cherry eye are often subtle. Many affected dogs will only present with mild conjunctival hyperemia (redness) and epiphora (excessive tearing) in the affected eye. Some dogs may exhibit signs of discomfort, such as rubbing or scratching the eye with their paws. The third eyelid may appear slightly swollen or inflamed. Careful observation is crucial during this phase, as early intervention can often simplify treatment.

Progressive Symptoms:

As the condition progresses, a more distinct, reddish-pink mass becomes visible at the inner corner of the eye. Initially, this mass, which is the enlarged nictitating membrane gland, may be small, resembling a pea or a small bean. However, it typically grows rapidly over a period of 3-7 days, potentially reaching the size of a large bean or even a grape. The color may transition from a light pink to a deeper, purplish-red hue as the condition worsens. In the early stages, the mass might temporarily retract into the eyelid, but as it enlarges, it becomes permanently prolapsed and visibly protruding.

Associated Symptoms and Complications:

Beyond the characteristic mass, cherry eye can lead to several secondary complications. The constant irritation from the exposed gland frequently results in increased tearing, often soaking the fur below the eye. Conjunctivitis (inflammation of the conjunctiva) is common, accompanied by a thickened, mucopurulent discharge. Chronic rubbing can further exacerbate the problem, potentially causing corneal abrasions or ulcers. The increased inflammation and discomfort often lead to discomfort and irritation, causing the dog to frequently scratch its eyes with its paws. This constant irritation can further damage the cornea and compromise vision. In severe, neglected cases, the protruding gland might ulcerate or become infected, requiring immediate veterinary attention.

Differentiating Cherry Eye from Other Conditions:

It is essential to distinguish cherry eye from other eye conditions that might present with similar symptoms. For example, a conjunctival tumor or a foreign body lodged in the eye could mimic the appearance of cherry eye. A thorough examination by a veterinarian is necessary to accurately diagnose the condition and rule out other possibilities. The key distinguishing features of cherry eye include the location of the mass (at the inner corner of the eye) and its characteristic pink or reddish color.

Underlying Causes and Risk Factors:

The precise etiology of cherry eye remains somewhat elusive, likely resulting from a multifactorial interplay of genetic predisposition and environmental factors. Proposed causes include:

Genetic predisposition: Certain breeds, such as Pekingese, Shih Tzu, Bulldogs, Cocker Spaniels, and others, show a higher incidence of cherry eye, strongly suggesting a genetic component. This implies that the underlying anatomical structure of the nictitating membrane gland and its supporting tissues might be inherently weaker or more prone to prolapse in these breeds.

Developmental abnormalities: Anatomic defects involving the connective tissues supporting the nictitating membrane gland could also contribute to prolapse. These defects might be congenital or acquired later in life.

Irritation and inflammation: Chronic irritation from allergens, foreign bodies, or infections might lead to inflammation and subsequent swelling of the nictitating membrane gland, eventually causing prolapse.

Overproduction of glandular secretions: Excessive secretion from the gland itself might place increased strain on the supporting tissues, increasing susceptibility to prolapse.

Trauma: Direct trauma to the eye area, although less common, could also potentially contribute to cherry eye.

Treatment Options:

Unfortunately, medical management is largely ineffective for cherry eye. The primary treatment is surgical intervention. The most common surgical approach involves repositioning or removal of the prolapsed nictitating membrane gland. While complete removal is simpler and faster, it can result in dry eye due to the loss of some tear production. Therefore, the choice of surgical technique should be carefully evaluated by the veterinarian, considering the size, extent of inflammation, and general health of the dog.

Post-operative Care:

Post-operative care is critical for successful treatment. The veterinarian will typically prescribe ophthalmic antibiotics to prevent infection and may recommend the use of an Elizabethan collar to prevent the dog from scratching or rubbing the eye. Regular monitoring by the veterinary professional is essential to detect any potential complications.

Conclusion:

Canine cherry eye, while not usually life-threatening, can cause significant discomfort and potentially lead to more severe eye problems if left untreated. Early diagnosis and prompt surgical intervention are crucial to minimize complications and ensure the dog’s eye health and comfort. Owners should always consult with a veterinarian for accurate diagnosis and treatment recommendations.