When speaking of glaucoma, eye doctors are hearing a new term, Corneal Hysteresis.
Corneal Hysteresis is a value that tells us the “shock-absorbing ability” of the eye and it is measured by an Ocular Response Analyzer. A CH below 10 is said to be low, that is bad thing. A CH of above 10 is said to be high, that is a good thing. “Essentially, eyes that are good shock absorbers (high CH) are less likely to develop glaucoma and less likely to experience glaucomatous progression. Conversely, eyes that are poor shock absorbers (low CH) are more likely to develop glaucoma and [have] disease progression. CH reflects how an eye responds to stress (elevated IOP) and whether the eye experiences the brunt of that stress (low CH) or is able to dissipate the energy and protect the optic nerve (high CH).”
After 70 years of using the Goldmann Applanation Tonometry tests for eye pressure measurement, technology advances is bringing CH to the forefront. Most patients recognize GAT as “the blue light” test that doctors do after putting those “sticky, stingy yellow drops” in their eyes. Any medical advances that provide new information will ultimately lead to better diagnosis and treatment. Is the GAT at the end of its useful cycle? Doubtful. More likely the CH will be used against the GAT to arm eye doctors with the best information to manage patient’s glaucoma.
Whatever tests eye care professionals deem as the best to use to help them screen for and manage glaucoma, one thing is for certain: in order for them to do that test, they first have to get patients in to see them. It is imperative for patients not to skip their annual eye exam.
According to the CDC, “about 3 million Americans have glaucoma. It is the second leading cause of blindness worldwide. Open-angle glaucoma, the most common form, results in increased eye pressure. There are often no early symptoms, which is why 50% of people with glaucoma don’t know they have the disease.”