The body is largely run by blood vessels. While the brain is the control room the heart is the engine. The blood vessels carry the blood being pumped by the heart around the body. It, therefore, presents an intriguing question, is there any part of the body that is not reached by blood vessels?
Hair, nails and tooth enamel are all considered dead cells so they are not reached by blood vessels. If there were blood vessels in your hair that would be pretty scary and would make an average haircut an ugly operation. Aside from these dead cells, there is only one part of the body that is not served by blood vessels, the cornea.
The cornea is a transparent, protective layer near the front of the eye. It is the only living part of the body that is not reached by a blood vessel. How then does it stay alive? Oxygen and nutrients are actually able to look after the Cornea by diffusing directly from tear fluid on the outside of the eye as well as from the large, moist liquid between the lens and the cornea, called the aqueous humour.
This is why some people have issues, caused by contact lenses. Contact lenses reduce the oxygen supply from the outside of the eye that can lead to medical conditions for the cornea, the most notable being neovascularization. Neovascularisation is a condition where there is the growth of blood vessels into the cornea. It can appear like you are extremely bloodshot or that there are large veins of blood along the outside of your eye spreading into your cornea. It can cause you to lose to your eyesight and is why it is incredibly important to avoid wearing contact lenses for extended periods of time. Be careful if you are a contact lens wearer as although the risks are not as high thanks to improved, newer lenses, it is still something to be wary of.