Glaucoma suspect

A primary open angle glaucoma suspect is someone who has abnormal findings in a few of the examinations or tests but has normal findings in the rest of the examinations. For example, a person may have suspicious-looking optic discs but have a normal visual field test, open anterior chamber angles and an intraocular pressure within the normal range. This person would be labeled a glaucoma suspect. POAG suspects fall within a spectrum ranging from low risk suspects to high risk suspects depending on the examination and test results and the presence of risk factors in the patient’s medical and family history. Sometimes, the ophthalmologist may decide to begin treatment for a high risk suspect if conversion to actual glaucoma is considered highly likely.

A primary angle closure suspect is someone whose iris is in a position where it could easily occlude the anterior chamber angle. This person has no symptoms of angle closure and the risky iris position is usually found on routine check-up or when the person consults an ophthalmologist for an unrelated complaint. The level of risk of angle occlusion varies. The ophthalmologist may decide to simply observe the low risk suspect or may decide to perform prophylactic laser treatment (laser iridotomy and/or iridoplasty) on a high risk suspect.

Ocular Hypertension

Ocular hypertension refers to the condition where the intraocular pressure (IOP) is above the normal range but there are no other signs of glaucoma. This condition is usually found on routine check-up or when the person consults an ophthalmologist for an unrelated complaint. An ocular hypertensive can be considered an open angle glaucoma suspect. A recent large, randomized, controlled, treatment trial of ocular hypertensives found that approximately 10% of them went on to develop open angle glaucoma if left untreated.

Ocular hypertensive individuals can be grouped into two categories: 1) those who simply have IOPs that are greater than the average for the population but which IOPs are normal for their eyes, and 2) those who have open angle glaucoma but have not yet developed any detectable optic disc or visual field changes. Because it is sometimes difficult to tell which category an ocular hypertensive belongs in, the ophthalmologist will need to monitor that person regularly. Some ocular hypertensives may have a higher risk of actually having glaucoma than other ocular hypertensives. Because high risk ocular hypertensives may benefit from IOP-lowering treatment, the ophthalmologist may decide to begin treatment even before any signs of glaucoma are detected. Moderate and low risk ocular hypertensives can just be observed.

References:

1. Kass et al. The Ocular Hypertension Treatment Study: A randomized trial determines that topical ocular hypotensive medication delays or prevents the onset of primary open-angle glaucoma. Archives of Ophthalmology 2002; 120:701-713.
2. Ritch R, Shields MB, Krupin T (Eds). The Glaucomas, 2^nd Edition. St. Louis, Missouri, USA, 1996, Mosby-Year Book, Inc.
3. Epstein DL, Allingham RR, Schuman JS (Eds). Chandler and Grant’s Glaucoma, 4^th Edition. Baltimore, Maryland, USA, 1997, Williams & Wilkins.
4. South East Asian Glaucoma Interest Group. Asia-Pacific Glaucoma Guidelines. Sydney, Australia, 2003-2004, SEAGIG.
5. European Glaucoma Society. Terminology and Guidelines for Glaucoma 2^nd Ed. Savona, Italy, 2003, EGS.