What anatomical event produces cherry eye in dogs?

Prolapse of the gland of the third eyelid Cherry eye, or nictitans gland prolapse, occurs when the gland of the third eyelid protrudes from its normal position as a reddish, cherry-like mass.

Eversion of the lower eyelid margin

Herniation of orbital fat into the conjunctiva

Protrusion of the lacrimal sac through the medial canthus

What is the normal function of the nictitans gland that prolapses in cherry eye?

Producing tears and maintaining ocular lubrication The gland of the third eyelid plays a vital role in producing tears and keeping the ocular surface lubricated.

Draining aqueous humour from the anterior chamber

Secreting the meibomian lipid layer

Housing immune cells that clear corneal debris

What is the usual laterality of cherry eye?

Typically unilateral, though both eyes can be affected Cherry eye usually occurs in one eye, but in some cases both eyes are involved.

Always bilateral at presentation

Always confined to the left eye

Bilateral in every brachycephalic dog

Which breeds are described as more commonly affected by cherry eye?

Bulldogs, Cocker Spaniels and Beagles Breed predisposition is a recognised contributor, with Bulldogs, Cocker Spaniels and Beagles among the breeds most commonly affected.

Greyhounds, Whippets and Salukis

German Shepherds and Belgian Malinois

Which structural weakness is thought to allow the nictitans gland to prolapse in cherry eye?

Laxity of the connective tissue supporting the gland Weakness or laxity of the connective tissue that normally anchors the nictitans gland is among the proposed contributing factors.

Thinning of the overlying corneal epithelium

Shortening of the extraocular muscle insertions

Dehiscence of the orbital septum

Why is fluorescein dye applied during the assessment of a dog with cherry eye?

To assess for corneal ulceration or surface abnormality Fluorescein staining checks the ocular surface for corneal ulceration and other abnormalities that may accompany the prolapse.

To measure intraocular pressure indirectly

To visualise the nasolacrimal duct anatomy

To stain the prolapsed gland for surgical planning

What is the purpose of the Schirmer tear test in a dog with cherry eye?

To evaluate for dry eye, or keratoconjunctivitis sicca The Schirmer tear test measures tear production to look for keratoconjunctivitis sicca, which can follow cherry eye in some cases.

To grade the degree of conjunctival inflammation

To confirm the gland has prolapsed

To detect bacterial overgrowth of the tear film

What is the mainstay of treatment for cherry eye in animals?

Surgery to reposition or replace the prolapsed gland Treatment typically means surgical intervention to reposition or replace the gland and restore normal anatomy and function.

A course of topical antibiotic drops alone

Manual digital reduction repeated by the owner

Systemic anti-inflammatory therapy until it regresses

In which circumstances is surgical excision of the prolapsed gland considered in cherry eye?

In severe or recurrent cases Complete or partial removal of the gland may be considered where cherry eye is severe or recurrent, rather than as the routine first choice.

As the routine first procedure in every case

Only in animals under six months of age

Only when the opposite eye is already blind

After surgery for cherry eye, which outcomes should be monitored?

Recurrence of the prolapse and development of dry eye The prognosis after surgery is generally favourable, but recurrence and keratoconjunctivitis sicca should be watched for postoperatively.

Progressive cataract formation and lens luxation

Retinal detachment and vitreous haemorrhage

Secondary glaucoma from angle closure

Cherry Eye: Understanding a Common Ocular Disorder

Overview

Cherry eye, scientifically known as nictitans gland prolapse or prolapsed nictitating membrane, is a frequently encountered ocular disorder affecting dogs and occasionally other animals.

It occurs when the gland of the third eyelid (nictitating membrane) protrudes or prolapses from its normal position, resulting in the appearance of a reddish or pinkish mass resembling a cherry, hence the name.

This article aims to provide a comprehensive overview of cherry eye in animals, covering its disease entity, causes, clinical signs, diagnosis, treatment options, prognosis, and relevant references.

Cherry Eye Disease Entity

Cherry eye is characterized by the prolapse or protrusion of the gland of the third eyelid, also known as the nictitans gland or the gland of the third eyelid.

This gland plays a vital role in producing tears and maintaining ocular lubrication. When the gland prolapses, it becomes exposed and visible in the corner of the affected eye, presenting as a reddish or pinkish mass resembling a cherry.

While cherry eye typically occurs unilaterally, it can affect both eyes in some cases.

Test your knowledge 10 questions from this article

Causes

The precise cause of cherry eye in animals is not fully understood, but several factors may contribute to its development.

These factors include:

Weakness or laxity of the connective tissue that supports the nictitans gland.
Breed predisposition, with certain breeds such as Bulldogs, Cocker Spaniels, and Beagles being more commonly affected.
Trauma or injury to the eye or surrounding structures.
Congenital predisposition or genetic factors.

While the underlying cause may vary among individual cases, cherry eye is generally considered a multifactorial condition with a genetic predisposition in certain breeds.

Cherry Eye Clinical Signs

The most prominent clinical sign of cherry eye in animals is the presence of a reddish or pinkish mass protruding from the corner of the affected eye, resembling a cherry. Other clinical signs may include:

Ocular irritation or discomfort leads to rubbing or pawing at the affected eye.
Increased tear production (epiphora) due to ocular irritation.
Conjunctivitis or inflammation of the conjunctiva surrounding the prolapsed gland.
Secondary ocular complications such as corneal ulceration or keratoconjunctivitis sicca (dry eye) if left untreated.

Diagnosis

Diagnosing cherry eye in animals is usually straightforward based on the characteristic appearance of the prolapsed gland.

Cherry Eye

However, additional diagnostic tests may be performed to assess ocular health and rule out underlying conditions.

Diagnostic steps may include:

Ophthalmic examination: A thorough examination of the affected eye by a veterinarian or veterinary ophthalmologist to confirm the presence of cherry eye and evaluate ocular health.
Fluorescein staining: Application of fluorescein dye to the eye to assess for corneal ulceration or other ocular surface abnormalities.
Schirmer tear test: Measurement of tear production to evaluate for the presence of dry eye (keratoconjunctivitis sicca), which may occur secondary to cherry eye in some cases.

Cherry eye Treatment

The treatment of cherry eye in animals typically involves surgical intervention to reposition or replace the prolapsed gland and restore normal anatomy and function. Common treatment options include:

Surgical replacement (tuck) technique: Surgical repositioning of the prolapsed gland using sutures or tissue adhesives to secure it in its normal anatomical position.
Surgical removal (excision) technique: Complete or partial removal of the prolapsed gland, which may be considered in cases of severe or recurrent cherry eye.

Prognosis

The prognosis for animals with cherry eye is generally favorable following appropriate surgical treatment.

However, the risk of recurrence or development of complications such as dry eye (keratoconjunctivitis sicca) should be monitored postoperatively.

With prompt diagnosis and timely surgical intervention, most animals can achieve a successful outcome and return to normal ocular function.

References

Davidson, H. J., & Kuonen, V. J. (2005). Disorders of the canine third eyelid gland. Veterinary Clinics of North America: Small Animal Practice, 35(1), 213-232.
Giuliano, E. A., Giuliano, A. M., & Moore, C. P. (2006). Treatment of cherry eye in dogs: a new minimally invasive technique. Veterinary Ophthalmology, 9(5), 291-296.
Park, S. A., Ahn, H. J., Lee, S. H., & Yang, J. W. (2019). Clinical characteristics and surgical outcomes of cherry eye in 35 dogs (39 eyes). Veterinary Ophthalmology, 22(3), 354-360.
Ramsey, D. T., & Plummer, C. E. (2013). Cherry eye. Clinical Techniques in Small Animal Practice, 28(2), 104-107.

Test yourself

A few questions straight from this article.

1 / 10 0 correct

What anatomical event produces cherry eye in dogs?
Cherry eye, or nictitans gland prolapse, occurs when the gland of the third eyelid protrudes from its normal position as a reddish, cherry-like mass.
What is the normal function of the nictitans gland that prolapses in cherry eye?
The gland of the third eyelid plays a vital role in producing tears and keeping the ocular surface lubricated.
What is the usual laterality of cherry eye?
Cherry eye usually occurs in one eye, but in some cases both eyes are involved.
Which breeds are described as more commonly affected by cherry eye?
Breed predisposition is a recognised contributor, with Bulldogs, Cocker Spaniels and Beagles among the breeds most commonly affected.
Which structural weakness is thought to allow the nictitans gland to prolapse in cherry eye?
Weakness or laxity of the connective tissue that normally anchors the nictitans gland is among the proposed contributing factors.
Why is fluorescein dye applied during the assessment of a dog with cherry eye?
Fluorescein staining checks the ocular surface for corneal ulceration and other abnormalities that may accompany the prolapse.
What is the purpose of the Schirmer tear test in a dog with cherry eye?
The Schirmer tear test measures tear production to look for keratoconjunctivitis sicca, which can follow cherry eye in some cases.
What is the mainstay of treatment for cherry eye in animals?
Treatment typically means surgical intervention to reposition or replace the gland and restore normal anatomy and function.
In which circumstances is surgical excision of the prolapsed gland considered in cherry eye?
Complete or partial removal of the gland may be considered where cherry eye is severe or recurrent, rather than as the routine first choice.
After surgery for cherry eye, which outcomes should be monitored?
The prognosis after surgery is generally favourable, but recurrence and keratoconjunctivitis sicca should be watched for postoperatively.