Cherry Eye: Surgery Options and Recurrence
A red lump in the corner of a young dog's eye is usually cherry eye. Why vets put the gland back rather than remove it, and what's known about recurrence.
Written by thecanineledger
A 2018 review of the published studies on cherry eye surgery reached a blunt conclusion: “there is currently insufficient evidence to ascribe superior surgical success rates and lacrimal outcomes to any particular technique” (White and Brennan, Veterinary Sciences 2018). Lacrimal outcomes are effects on tear production.
While there is no proven best operation, there is broad agreement on one point. The gland should be put back, not cut out. This page explains what cherry eye is, which dogs get it, and what the evidence says about surgery.
1. What cherry eye is
Dogs have a third eyelid in the inner corner of each eye, with a tear gland attached. The Merck Veterinary Manual’s owner page explains that in cherry eye, “the gland of the nictitating membrane thickens, slips out of its proper place, and sticks out over the edge of the membrane.” The result is a “red, swollen mass next to the lower eyelid” (Merck, Disorders of the Nasal Cavity and Tear Ducts in Dogs).
It rarely fixes itself. Merck: “Although the swelling may go down for short periods, the nictitating membrane gland often remains dislocated.”
Why the gland matters. “Because this gland is important in the production of tears, your veterinarian will want to preserve it, if possible.”
Our note: We haven’t read a source on how soon to book, or on whether the gland gets harder to replace over time. Ask your vet.
2. Which dogs get it
A 2022 VetCompass study of 905,543 dogs at UK primary-care practices found cherry eye in 0.20% of dogs in a year (O’Neill et al., PLoS One 2022).
Young dogs. “The median age at first diagnosis was 0.63 years”, about 7 months. Dogs under 1 year had nearly 11 times the odds of dogs aged 2 to 4.
Breeds. Compared with crossbreds, the highest odds were in the Neapolitan Mastiff (about 34 times), English Bulldog (about 24 times), Cane Corso (about 15 times), Lhasa Apso (about 12 times) and American Cocker Spaniel (about 12 times). Nearly 5% of English Bulldogs in the study had cherry eye in a single year.
Face shape. Flat-faced breeds had about 6.7 times the odds of breeds with medium-length faces.
Probably inherited. The authors say the results “suggest a hereditary involvement in PNMG development.” PNMG is the formal name: prolapsed nictitating membrane gland.
→ Choosing a Breed or a Mix: The Health Data Breeders Don’t Lead With
3. Replace, don’t remove
Removal used to be standard. The 2018 review notes that “gland excision was formerly the mainstay of treatment”, but that “removal is now discouraged due to concerns for subsequent development of dry eye”.
The link to dry eye. Merck says dogs with cherry eye “appear to be more likely to develop dry eye (see below) later in life, especially if the gland is removed.” The VetCompass authors say that “surgical reposition of the gland is considered the gold standard therapy”.
A caution about certainty. The 2018 review says removal “may predispose to development of KCS, but further studies are needed to confirm this association”. KCS is dry eye.
→ Dry Eye (KCS): Why Treatment Is Usually Lifelong
4. The surgical options, and recurrence
Many techniques. The 2018 review found “Seven different replacement techniques”, plus removal, across 15 publications. Merck describes the two main approaches. The gland is “stitched to the connective tissue around the edge of the eye or covered with nearby mucous membrane using an envelope or pocket technique.”
Recurrence. One pocket technique “is favored by a number of veterinarians”, the review says. For it, the review’s pooled analysis “yielded an overall failure rate of 3% (95% CI 1–7%)”. Failure here means the gland slipping out again.
Why that number is uncertain. The review found that “Outcomes reporting was heterogeneous and provided limited detail on lacrimal outcomes or on breed propensity for recurrence.” Most included studies were case series. It concluded that “Insufficient data precluded comparison of techniques”.
The cartilage. The VetCompass authors note that deformities of the third eyelid’s cartilage have been linked both to cherry eye and “predisposing to re-prolapse after surgical correction”.
Our note: We based “Most included studies were case series” on the review’s study table. The review couldn’t compare recurrence for other techniques, so we don’t give those figures.
Our note: The VetCompass paper says cherry eye “can be unilateral or bilateral”, but gives no rate in the sections we read.
→ How Risky Is Anaesthesia for My Dog?
5. What we could not verify
| Commonly said | What we found |
|---|---|
| “Just have the gland removed” | No longer advised. Removal is discouraged because of the risk of dry eye. |
| “It will pop back in on its own” | Usually not for long. Merck says the gland often stays dislocated. |
| “One surgery is clearly the best” | Not proven. A 2018 review found insufficient evidence to rank the techniques. |
| “Surgery always works first time” | Mostly, but not always. The pooled failure rate for the pocket technique was about 3%, from limited data. |
| “Cherry eye is caused by injury” | The evidence points to inheritance. Young age and breed predisposition suggest a hereditary cause. |
Sources
- White C, Brennan ML. An Evidence-Based Rapid Review of Surgical Techniques for Correction of Prolapsed Nictitans Glands in Dogs. Vet Sci 2018: rapid review, 15 publications
- O’Neill DG, Yin Y, Tetas Pont R, et al. Breed and conformational predispositions for prolapsed nictitating membrane gland (PNMG) in dogs in the UK: A VetCompass study. PLoS One 2022: VetCompass, 905,543 dogs
- Merck Veterinary Manual: Disorders of the Nasal Cavity and Tear Ducts in Dogs (pet owner version; Gelatt, DACVO; last updated Sept 2024)
Always confirm with your vet before acting on anything on this page.