Turning to Rust?

How many times have we been told a specific tissue is composed of 99.8% water or this structure is 98.8% water? Okay, we're carrying lots of water around, but what about that other 1.2%? Our cells are loaded with proteins, chemicals and minerals. This applies to the eye as well.

Were you aware that the tears contain iron? We're not sure what role iron plays in the tear film, but we do know that nothing in nature happens by accident. Any clinical significance? Plenty!

The healthy ocular surface is smooth, uniform and evenly contoured. Anything that disrupts that healthy surface (bumps or divots) will cause the tears to become unevenly distributed along the ocular surface. Anybody driving on a rainy day with chewed-up wiper blades knows what I'm talking about. Small puddles of stagnant tears can collect and iron molecules in the tears can become deposited on the corneal surface. Elemental iron is attracted to epithelial cells and these are the exact cells that coat the outer cornea. The result is an iron deposition line.

Iron lines can be seen with the eye doctor's slit lamp biomicroscope. They have a brown or rust color. Here are some common iron lines seen on the cornea:

• Hudson-Stahli line: where lower lid (tear film strip) rests on the corneal surface


• Fleischer line: circular ring in folks with irregular astigmatism (keratoconus)


• Stocker's line: adjacent to encroaching pterygium


• Ferry's line: adjacent to the bump caused by a glaucoma filtering bleb


• Waring line: healed RK incisions

Don't freak if your doctor tells you that you have an iron line. None of these iron lines represent eye disease, merely a clinical finding caused by local iron deposition. No treatment is necessary.

Are there other minerals associated with the eye? Sure! There's copper, calcium, silver and many more! Visit us often to learn more.

Related Topics:

• WebMD Video: Contact Lenses Help Patients with Corneal Disease
• WebMD Video: Tips for Better Vision

Technorati Tags: vision, iron lines, cornea