1. Vision is so important to humans that almost half of your brain’s capacity is dedicated to visual perception.

2. The most active muscles in your body are the muscles that move your eyes.

3. The surface tissue of your cornea (the epithelium) is one of the quickest-healing tissues in your body. The entire corneal surface can turn over every 7 days.

4. Your eyes can get sunburned. It is called photokeratitis and it can make the corneal epithelium slough off just like your skin peels after a sunburn.

5. Ommatophobia is the fear of eyes.

6. You blink on average about 15 to 20 times per minute. That blink rate may decrease by 50% when you are doing a visually demanding task like reading or working on a computer – and that’s one reason those tasks can lead to more dry-eye symptoms.

7. Your retinas see the world upside down, but your brain flips the image around for you.

8. If you are farsighted (hyperopia) your eye is short, and if you are shortsighted (myopia) your eye is long.

9. An eyelash has a lifespan of about 5 months. If an eyelash falls out it takes about 6 weeks to fully grow back.

10. All blue-eyed people are related. The first person with blue eyes was thought to have lived 6,000 to 10,000 years ago. All people before that had brown eyes.

11. One in every 12 males has some degree of “color blindness.”

Sunglasses are a great fashion accessory, but their most important job is to protect your eyes from the sun's ultraviolet rays

There are certain eye conditions where an injection into your eye might be recommended.

Injections into the eye, specifically into the vitreous or gel-filled cavity of the eye, are called intravitreal injections.

In Part 1 of ‘Why Do I Need an Injection in my Eye?’ we talked mostly about anti-vascular endothelial growth factor (anti-VEGF) injections. Anti-VEGF injections are probably the most commonly injected agents and they are used to treat wet age-related macular degeneration (ARMD), diabetic retinopathy, and retinal vein occlusion.  

But there are other injections that may be used as treatment.

Another injected medication used in combination with Anti-VEGF agents to treat wet macular degeneration, diabetic retinopathy and retinal vein occlusion are steroids. Additionally, steroids can be used to treat inflammation, or uveitis, in the eye. There is a steroid implant called Ozurdex, that looks like a white pellet and can last up to 3 months in the eye. The downside of steroids is that they can increase eye pressure and cause progression of cataracts.  

Antibiotics are another type of medication that is injected into the eye. Sometimes an infection called endophthalmitis can develop inside the eye. This can occur after eye surgery or a penetrating injury to the eye. The presenting signs and symptoms of endophthalmitis are loss of vision, eye pain and redness of the eye. Bacteria is usually the cause of the infection, and antibiotics are the treatment. The best way to deliver the antibiotics is to inject them directly into the eye.  

Another relatively new injection is Jetrea, an enzyme that breaks down the vitreous adhesions that may develop on the surface of the retina. As we age, the vitreous contracts away from the retinal surface.  When this occurs over the macula, the region responsible for fine vision, the result is visual distortion. Jetrea is an injection that will dissolve the vitreous adhesions and relieve the traction on the retina.  Prior to the advent of Jetrea, the only treatment would have been surgery to physically remove the vitreous jelly and traction on the retina.   

The next time you visit your eye doctor and are told you need an injection of medication, it will likely be one of the above agents.

Article contributed by Dr. Jane Pan