Which Part of the Eye Has No Blood Supply?
The cornea is the only part of the eye, and indeed the only part of the human body, that has no blood supply. It receives oxygen directly from the air.
The cornea, the transparent front part of the eye, is incredibly unique in its lack of blood vessels. This avascular nature is crucial for its transparency, allowing light to pass through unimpeded to reach the retina. Without a blood supply, the cornea relies on diffusion of oxygen and nutrients from the surrounding tissues and the air for its sustenance. This efficient oxygen uptake is facilitated by its thinness and proximity to the atmosphere.
Why is the lack of blood vessels important?
- Transparency: Blood vessels would scatter light, reducing the clarity of vision.
- Immune privilege: The lack of blood vessels helps to protect the cornea from immune system reactions that could damage its delicate structure.
Several sources corroborate this information: Shoreline Vision (https://www.shorelinevision.com/cornea/) states that "The cornea is the only part of a human body that has no blood supply; it gets oxygen directly through the air." This is further supported by Baptist Health (https://www.baptist-health.com/blog/amazing-facts-about-the-human-body), which reinforces the fact that the cornea is the only part of the body without a blood supply. Exeter Eye (https://www.exetereye.co.uk/the-eye/eye-anatomy/) also notes that the cornea "contains no blood vessels".
