None of us like getting something in our eyes. Now imagine having an eyelash that permanently rubs against them. OUCH! This problem is called distichiasis, and it can cause serious eye damage. In this week’s blog, I share some eye-opening information about distichiasis – happy reading!
Distichiasis – What is it?
The eyelids contain many special structures. Eyelashes (also called cilia) in dogs are normally produced in the glands of Zeis found within the eyelid margins. Cats normally don’t have cilia. The eyelids also have tarsal glands (also called meibomian glands) whose openings are normally visible on the eyelid margin. A grayish-white secretion can be expressed from them with gentle finger pressure. This secretion forms part of the eye’s normal tears and coats the eyelids to prevent overflow of tears. Under normal circumstances, tarsal/meibomian glands do not contain any eyelashes. Distichiasis a condition in which cilia are abnormally found in the tarsal glands.
Illustration courtesy of Eye Care for Animals
Distichiasis – What does it look like?
Cilia found abnormally in tarsal/meibomian glands may come into contact with the cornea (the clear part of the eyes) to cause irritation. Interestingly, distichiae don’t always cause problems for dogs. However, for some dogs, these abnormal eyelashes can cause meaningful discomfort, and can damage the cornea. The common clinical signs of distichiasis are:
- Epiphora – excessive tearing and staining of facial hairs
- Blepharospasm – involuntary closing of the eyelids due to discomfort; affected pets look like they are winking
- Chronic conjunctival erythema – the conjunctiva is a membrane that coats the outer surface of the eyeball and the inner surface of the eyelids; when present, distichiae irritate the conjunctiva to cause reddening/erythema
- Corneal ulcers – distichiae can directly damage the cornea
Any dog can develop distichiasis, but some breeds are over-represented. These include:
- Parson Russell terriers
- Welsh springer spaniels
- Cocker spaniels (American and English)
- Cavalier King Charles Spaniels
- Flat-coated retrievers
- Shih Tzus
- Dachshunds
- English bulldogs
Distichiasis – How is it diagnosed?
Distichiae can be readily observed during a routine examination of the eyelids, but some are small and/or fine enough to require magnification to visualize.
A single distichia in dog
If your family veterinarian suspects your pet is living with distichiasis, you will likely be referred to a board-certified veterinary ophthalmologist who has specialized equipment to accurately diagnose this problem.
A board-certified veterinary ophthalmologist examines a dog’s eyes
Distichiasis – How is it treated?
Remember not all patients with distichiasis require treatment. Indeed, many pets with distichiae are quite comfortable and don’t need any intervention. However, if a patient is uncomfortable due to distichiasis, intervention is indicated. Some primary care veterinarians may be comfortable performing the required therapies. However, pet parents should know treatment can result in irreversible eyelid damage if not performed appropriately. For that reason, partnering with a board-certified veterinary ophthalmologist can be instrumental in maximizing the likelihood of pain-free outcome.
Potential treatments for distichiasis are:
- Manual epilation – plucking by hand the distichiae using special instruments every 4-6 weeks
- Electroepilation – destruction of the tarsal/meibomian gland with electrolysis, the application of a direct low electrical current to the affected gland
- Microcryoepilation – the application of nitrous oxide or liquid nitrogen probe over the affected tarsal/meibomian gland to freeze the follicle; the distichiae are then manually plucked
- Surgery – occasionally an ophthalmologist may recommend surgical removal of the affected tarsal/meibomian gland
An ophthalmologist performs microcryoepilation to remove distichia in a dog
The take-away message about distichiasis in dogs…
Distichiae are abnormal eyelashes found within specific glands of the eyelids. Many times these abnormal hairs cause absolutely no discomfort to pets. However, they can occasionally cause discomfort and subsequently damage the corneas of some dogs. With an accurate diagnosis, distichiasis can be effectively treated without permanent damage. Consultation with a board-certified veterinary ophthalmologist will help ensure your pet receives the most appropriate treatment.
To find a board-certified veterinary ophthalmologist, please visit the American College of Veterinary Ophthalmologists.
Wishing you wet-nosed kisses,
cgb