Thursday, April 11, 2013

The Eye, It's Like a Beach Ball and an Ice Cream Sandwich

Oriole's perfect eye, clear, bright, no discharge, no squinting,  and  reflecting light beautifully.

There are a few more sensitive organs in the body than the eye. Have you ever gotten an eyelash stuck in your eye? Or a bug? Or even a scratch?

Here are some the signs of a painful eye.
1.     Squinting. We call it blepharospasm.
2.     Tearing. We call it epiphora.
3.     Discharge of any abnormal amount, consistency, or color.
4.     Rubbing. Whether that is in the form of your pet rubbing their eye with their paw, or rubbing their face on the ground.

 If you have ever scratched your eye then you know how painful it is. Your eye waters, it stings, and you don’t want to open it, so what do we do? we rub it, (although we should NEVER rub!). This can further damage the cornea, and make it more difficult to heal.

There are a few very important things for you to know about your pets eyes. I’m going to give you the simple eyeball primer, but even if you forget everything else I’m going to tell you, please just remember this one thing:

Many eye problems can be fixed quickly, easily, and inexpensively IF YOU GET HELP EARLY. Eye’s can get bad quickly BUT they can also get better quickly.

This is Dusty the dachshund. Note the grey/blue cloudy look to his eye.

Here is the patient I saw last week. Note that his eye looks "cloudy." A cloudy cornea is a swollen cornea.

Here’s a simplified anatomy lesson of the cornea of the eye.

The cornea is the thin transparent tissue that forms the globe of your eye. Think of the eye like a beach ball. The cornea is the thing that you touch when you hold the ball. If you cut a piece of the beach ball, for instance if you cut a small piece of the ball and looked at it in cross section under a microscope, it looks like an ice cream sandwich. The outside cookie part of the ice cream sandwich is the epithelium, it is made up of cells that are hydrophobic. A hydrophobic cell (think phobia = fear) repels water, that way when your cry the tears roll off of your cornea. We all naturally produce tears to lubricate our eye. It is our own little internal windshield washer and wiper system.

(What would happen if you didn't produce any tears? Think of running your car’s windshield wipers running without windshield wiper fluid or rain. This is called KCS, I will talk about it soon).

If you get a scratch on the top layer of your cookie sandwich it exposes the middle layer (the ice cream) called the stroma. The stroma is hydrophilic, it loves water. When the stroma is exposed to water (think tears) it gets sucked into the stroma causing it to swell. This causes the cornea to get cloudy.

When we see a patient come in with a cloudy cornea we use a special stain, called flourescein. If there is a tear in the outer (epithelium) cookie layer the flourescein will bind to the stroma and glow a bright green under a black light. The fluorescein helps us to identify how deep and how large the damage is. 

Dusty's eye takes up the fluorescein in a smal rectangular area just above the fingertip of his owner. The fluorescein also lines the edges of the eye. Sometimes it will even drip out of the nose.

Most acute (new/recent) corneal traumas are ulcers. An ulcer is classified as either an uncomplicated or indolent (meaning it is chronic and not healing).

An uncomplicated ulcer should be treated immediately. They should heal in about 3-5 days.

The patient that I saw the other day had been squinting for about 5 days. (Yes, I gave a small lecture about getting treatment for eyes ASAP!). Dusty, the dachshund was squinting and there was thick yellow discharge from his eye.

After his stain test was positive we put him on an ophthalmic antibiotic, eye drops for pain, and an e-collar so he couldn't rub the eye anymore. I also had Dusty’s owner bring him back in 3 days for a re-check.

Three days later Dusty’s eye looked great! The e-collar came off, the pain medicine stopped and he was well on his way to healing.

OK, here’s the rest of the important eye information.
1.     If the eye ever looks worse STOP using the medicine and get back to the vet ASAP.
2.     If the eye isn’t better in 3-5 days, get back to the vet ASAP.
3.     If your pet gets other clinical signs like sneezing, coughing, vomiting, not eating, excessive drinking, or any worsening of the eye get to the vet ASAP.

One more note any pet that has had more than two incidents of ulcers should have a thorough ophthalmic examination and be monitored very closely. Many pets are predisposed to recurrent ulcers due to an underlying ocular abnormality. Just like all of the rest of the tissue in our body, every time it is damaged it heals with a scar. Eventually your transparent cornea scars and it is like trying to look at the world through scratched thick eyeglasses that you just can't every get clean or clear again.

No comments:

Post a Comment