Equine Recurrent Uveitis (ERU), historically termed Moon Blindness or Periodic Ophthalmia due to its recurrent nature, is a not uncommon eye condition in horses. It is characterized by repeated episodes of inflammation in the uveal tract (from where the condition gets its name) which is the blood vessel rich layer that plays a vital role in the health and function of an eye. Because inflammation is ultimately damaging to the delicate structures within the eye, ERU can lead to vision loss as well as discomfort. If you suspect your horse may be suffering from ERU, it's essential to seek professional advice and support. At Equine Eye Consultants, we're here to help you manage this condition and ensure the best possible care for your horse.
ERU is an immune-mediated condition, meaning it occurs when the horse's immune system attacks its own tissues. The exact cause is not well understood, but certain factors like genetics, infection, or trauma may contribute to its development.
- Eyelid swelling
- Sensitivity to light
- Excessive tearing or eye discharge
- Squinting or keeping the eye closed
- Colour changes to the eye including clouding of the eyes surface
- Vision loss in advanced cases
It's crucial to consult a veterinary surgeon for accurate diagnosis and appropriate treatment as different eye conditions can present with similar symptoms which may require distinctly different treatments. Management of ERU involves reducing inflammation when flare ups occur and minimising the risks of further episodes. Treatment options may include:
- Anti-inflammatory medications at the correct dose, for the appropriate length of time which often means treatment beyond the resolution of clinical signs and ideally until the microscopic markers of inflammation have disappeared . Anti-inflammatory medications are provided by a variety of routes but typically invlove the applciaiton of eyedrops, medications by mouth and injections
- Suprachoroidal Cyclosporine Implants: These implants are surgically placed in the eye to deliver a slow, steady release of the immunosuppressive drug cyclosporine. In correctly chosen cases, they can reduce the frequency and severity of ERU 'attacks'
- Long-Acting Steroid Injections: Using the new SuproJect needle, veterinarians can administer long-acting corticosteroids to reduce inflammation in the eye. These injections typically provide relief for extended periods and can offset the need to apply eye drops.
- Low Dose Intravitreal Gentamicin Injections: This treatment option involves injecting a medication directly into the vitreous chamber of the eye in selected cases. The science behind why this treatment may be of benefit to certain horses is not well understood and there is a potential. albeit low for side effects, but anecdotal reports form veterinary ophthalmologists in many countries make it worthy of consideration in selected cases of ERU.
- Supportive Care: In addition to the above treatments, your veterinary surgeon may recommend other supportive measures like pupil dilating medication, management considerations to minimise the risk of eye trauma, general eye protection and optimising wider health.
- Eye removal (enucleation): although the primary aim of all treatment efforts is to maintain a functional and visual eye, there can come a point where removal of the affected eye can be in the best interests of the individual patient and their support team. Such surgery can typically be performed 'standing' and many patients for whom this treatment decision is required are noticably happier once the burden of a chronic eye complaint is lifted.
Equine Recurrent Uveitis is an often times challenging condition, but with the right management and care, many horses can maintain a good quality of eye health and function. If you're facing difficulties in managing ERU in your horse, don't hesitate to contact us. We are dedicated to providing comprehensive support and guidance to help you and your horse navigate this condition successfully in partnership with your primary veterinary surgeon.