When I was in veterinary school, my two-week clinical ophthalmology rotation involved 18 students crammed into the corner of a surgical suite watching phacoemulsification surgeries and getting a few opportunities to stain the eye of a horse. The minimal clinical experience meant that my comfort level with ophthalmic disease in general practice started low, and my confidence with diagnostics and interpretation was even lower. As a result, I know I’ve missed active ocular disease, didn’t focus on the helpful color changes and wasn’t as proactive as I could have been in educating pet owners about the early screening of at-risk breeds.
While I’ve taken wonderful continuing education courses since then, the examination and diagnostics of the eye become nearly impossible when a fearful or anxious patient reacts as you near its face. Learning strategies to reduce stress and allow efficient and accurate diagnostics is essential, and so is teaching clients to apply medications. The eye truly is the window into the body.
Here are commonly missed ophthalmic diseases we can spot easier if we eliminate anxious and fearful behavior.
Extra Eyelashes
Have you experienced a corneal abrasion firsthand? It’s one of the most painful conditions, and many brachycephalic breeds suffer from it off and on throughout life. The possible causes are many, but two we should not miss are ectopic cilia and distichiasis. For clarity, ectopic cilia describes single or multiple hairs growing through the inside of the eyelid, while distichiasis is an eyelash growing on the eyelid from an odd spot. These conditions are common in pugs, Boston terriers, English bulldogs, Shih Tzus, golden retrievers, collies and Cavalier King Charles spaniels.
If a client reports that your patient rubs an eye excessively at home, blinks frequently, keeps the eye closed or tears up excessively, we must do more than give a cursory glance using an ophthalmoscope from several feet away. Let’s not limit the quality of our medicine and our ability to charge appropriately for an ophthalmic workup.
We set ourselves up for failure if we’re not prepared to efficiently examine those pets. They are often in pain and photophobic, which needs to be at the forefront of our mind when planning the exam. I recommend saving the painful part of the body — in this case, the eyes —for last. When it’s time for the ocular exam, I make sure my diagnostic tools, including fluorescein stain strips, topical anesthetics, sterile saline eye wash, eye loupes and high-reward treats, are within arm’s reach. I dim the lights and kneel so that I am at eye level. As I place a soft, inner-tube collar around the neck, I distract the patient with peanut butter smeared on the wall or a lick mat. That approach often relaxes anxious patients, as I can touch the collar instead of the face.
Depending on the patient, I try to lift only the upper eyelid for the application of medications. With patients on an exam table, I find that gently pulling down the lower eyelid for eye drops might be easier. With smaller dogs and cats, I might use a compression garment or towel wrap for added anxiety reduction.
If significant fear or stress is present after all this, I recommend pausing and administering a light, reversible sedative. I also make sure to send home situational anti-anxiety medications for use before the recheck exam.
Dry Eyes
We often see patients present with painful, red, irritated eyes. However, compared with extra eyelashes, the condition has a few distinct and colorful observations more suggestive of keratoconjunctivitis sicca, otherwise known as KCS or dry eye. One we often gloss over is hyperpigmentation, which is especially true in reactive patients who avoid eye contact, cower, hide or distance themselves from our team members. Another common change we see is a thick, yellow mucoid discharge that occurs when the watery part of the tear film decreases.
When we identify such changes, most of us are good at recommending and performing a Schirmer tear test. While evaluating the number of tears produced is simple, the test can be challenging with anxious patients who might be in pain and unwilling to remain stationary for 15 to 30 seconds. Here is where the stress-reduction strategies mentioned above are needed.
It’s not enough to know whether your patient has dry eye. In many cases, it’s also necessary to rule out underlying diseases such as canine distemper, hypothyroidism and inner ear infections. The additional workup requires drawing blood and performing a thorough ear exam.
Don’t forget that dogs with dry eye can display both decreased tear production and a reduction in the quality of the tears. The latter can be difficult to confirm and might require a consult with a boarded veterinary ophthalmologist, especially if the patient isn’t responding positively to daily treatments.
Red Eyes
We sometimes skim over ophthalmic exams due to time constraints, patient unwillingness or our lack of aptitude. However, we can miss a significant amount of systemic disease if we ignore what the inside of the eye tells us. Here, I’m referring to uveitis, or inflammation of the eye’s anterior chamber.
Unlike a lot of primary ocular diseases that stay at or around the eye, uveitis can clue us into viral diseases like rabies and distemper, tick diseases like Lyme, bacterial diseases like leptospirosis, parasitic diseases like toxoplasmosis and fungal diseases like blastomycosis. Those diseases can damage other organ systems. By identifying uveitis sooner, we get a faster start to successful systemic treatments.
Like many ocular conditions, uveitis is quite colorful. Most of the visible parts of the eye will be red, but the cornea is possibly bluish and cloudy. The pupil can be constricted and small, and the patient might be photophobic. A patient’s avoidance of bright lights can make an effective evaluation challenging, especially when factoring in anxiety and fear.
The diagnosis is achieved by measuring intraocular pressure and finding a lower-than-normal repeatable reading. But, for accurate tonometry, we need a patient tolerant of gentle restraint. Unfortunately, applying tension to the neck can falsely increase intraocular pressure. It also can happen when the eyelids are forcibly held open on a struggling patient.
That is why the strategic placement of a yummy treat can keep the neck in the proper position, as can a soft inner-tube collar. Once uveitis is accurately confirmed, titer and PCR testing for infectious diseases become the next step, along with topical and systemic therapy.
Anxious and fearful behavior is a limiting factor in our ability to observe and accurately diagnose ophthalmic disease in dogs and cats. As our hospital teams become more proactive and habitual in stress-reduction strategies, we can do better medicine for our patients and clients and more thorough workups, bettering the financial health of our hospitals.
BEYOND THE EXAM
A thorough ophthalmic exam is essential to a complete physical exam. We often fail to realize how much information we can obtain from a gross exam and the incremental revenue generated by the following best practices:
- Fluorescein stain
- Schirmer tear test
- Tonometry
- Doppler blood pressure reading
- CBC/chemistry panel
- Urinalysis
- Leptospirosis PCR testing
- Toxoplasmosis PCR testing
- Viral PCR testing
- Tick titer or PCR testing
- Fungal titer or PCR testing