Accurately measuring eye pressure is key to assessing the risk of glaucoma, a condition that can lead to vision loss if not properly managed. The thickness of the cornea—the clear, outer layer of the eye—can significantly impact these measurements. Learn about the role of corneal thickness in diagnosing glaucoma, the potential risks of incorrect eye pressure readings, and the simple test used for corneal measurement.*

How Corneal Thickness Affects Eye Pressure Readings

The thickness of your cornea, also known as central corneal thickness (CCT), can affect the accuracy of your eye pressure readings. If your cornea is thicker than average, it might make your eye pressure seem higher than it actually is, possibly leading to an incorrect diagnosis of glaucoma and unnecessary treatment. 

On the other hand, if your cornea is thinner than average (less than 555 micrometers), your eye pressure could appear lower than it really is, which might cause a true risk of glaucoma to be missed. 

For example, an accurate CCT measurement could mean that a person initially diagnosed with normal tension glaucoma (NTG) may be more accurately treated for open-angle glaucoma (OAG), or an ocular hypertension (OH) diagnosis may be more appropriated assessed as normal.

Pachymetry: A Simple Test to Measure Corneal Thickness

Pachymetry is a quick, painless test that measures the thickness of your cornea. This procedure only takes about a minute for both eyes and provides crucial information that helps your eye doctor better interpret your eye pressure readings. 

Regular eye exams, including corneal thickness measurements, are especially important for those at higher risk of glaucoma, such as:

• Individuals over 60, 
• People of African descent over 40, and 
• Those with a family history of the disease.

By knowing your corneal thickness, your doctor can create a more accurate and personalized treatment plan if you’re at risk for glaucoma.

*Drake, M. (2022, March 23). The Importance of Corneal Thickness. The Glaucoma Research Foundation. https://glaucoma.org/articles/the-importance-of-corneal-thickness 

Responsum Health closely vets all sources to ensure that we always provide you with high-quality, reliable information. We do not, however, endorse or recommend any specific providers, treatments, or products, and the use of a given source does not imply an endorsement of any provider, treatment, medication, or procedure discussed within.