Predict the Onset Of Glaucoma

GLAUCOMA is an irreversible disease affecting the optic nerve and is usually caused by increased fluid pressure inside the eye. Glaucoma can be difficult to detect and diagnose. Measurement of eye pressure, examination of the optic nerve, and visual field testing, in particular, are simple, painless tests that help to determine if a patient has glaucoma. Recently, a new tool has become available to eye care specialists to help predict the development of glaucoma in patients with high eye pressure (ocular hypertension).

Researchers in the U.S. have developed a "glaucoma risk calculator" that estimates the five-year risk of a patient with ocular hypertension progressing to glaucoma.

The risk calculator was developed based on a comparison of data collected from patients with ocular hypertension and compared with the data obtained independently in the national multi-centre Ocular Hypertension Treatment Study (OHTS).

Predictive model

This recent study validated key patient risk factors that predict the progression from ocular hypertension to glaucoma — risk factors such as older age, high intraocular pressure, thin central cornea, larger vertical cup-to-disc ratio, and higher visual field pattern standard deviation index.

The risk calculator provides the eye specialist with a single number that estimates the risk for developing glaucoma within the next five years of an individual patient.

To simplify the predictive model for clinical use an easy-to-use slide rule-type device known as the STAR (Scoring Tool for Assessing Risk) has now become available.

Use of a risk calculator may improve allocation of healthcare resources and provides information that helps an eye care specialist manage a patient with ocular hypertension. As an example, it may be recommended that a patient who is at low risk for developing glaucoma be withdrawn from treatment and examined at less frequent intervals. In contrast, treatment might be recommended to another patient who is at high risk for developing glaucoma.

Help patients

Use of a risk calculator provides information that can help patients understand their condition, but is not meant to replace the experience and clinical judgment of an eye specialist. As new data become available, it is likely that new and improved risk calculators will emerge. These calculators may incorporate new risk factors or eliminate others to improve their predictive abilities.

It is recommended that everyone at risk should have regular comprehensive eye examination and not just a refraction or glass power check up. This is particularly important for those at highest risk, such as those with ocular hypertension or a family member with glaucoma.