It seems to surprise people when I tell them that their vision problem is a result of their blood pressure. As an eye doctor, I don’t think many patients expect me to comment on their blood pressure, but it most certainly can affect your eyes.

I’ve used this analogy before, so forgive me for being repetitive, but our eyes are basically like little balls of jelly. The front of the eye is used mostly to focus light on the back of the eye. The back of our eye is full of nerves and blood vessels. That’s right – blood vessels. Hundreds of very little, tiny blood vessels. And these blood vessels inside of our eyes are affected by your blood pressure just like the blood vessels in the rest of your body are.

In our eyes, the little arteries and veins in the back of our eye criss-cross like a mesh or web. These blood vessels are supposed to be very smooth and flexible, but as the blood pressure increases, it causes the little arteries to become harder and stiff. As the arteries stiffen they begin to choke-off the blood vessels that they cross. The vessel underneath gets choked, which restricts the flow of blood, and can actually cause the vessel underneath to ‘pop’. Think of this like a hose running from inside of your garage, down your driveway, and out to the street. If you back your car over the hose, the hose will compress a little when your tires are on top of it. If the rubber on your tires is very soft and flexible, it will not compress the hose as much. If the tires are over-inflated and very stiff rubber, they could choke-off the hose and restrict the flow of water. You can imagine that if this gets bad enough – the hose could pop. Okay, so I realize this isn’t the best analogy…but hopefully it makes sense.

So how does this affect your eyes? As you may figure, the eye needs a good supply of blood so it can function properly. If the blood vessels become choked-off and the eye doesn’t get enough blood, this can affect the function of your retina. But worse, if one of these blood vessels becomes choked-off enough, it will pop and bleed inside your eye. This usually happens rather suddenly, and can be devastating to vision. There are treatments for this, but they are far from perfect. And as usual, the best treatment is prevention. Get your eyes checked often and regularly. Your eye doctor will be able to look at the blood vessels in the back of your eye, and tell you whether or not your blood pressure is affecting your eyes.