Glaucoma is a serious eye condition that can cause irreversible vision loss if not detected and treated early. An eye doctor, also known as an optometrist, can diagnose glaucoma through a comprehensive eye exam. This exam includes a variety of tests to detect any signs of glaucoma, such as visual field testing, optical coherence tomography (OCT), and pachymetry. Visual field testing, also known as perimetry, is used to measure the full field of view.
This test can help identify any loss of peripheral vision, which is a common sign of glaucoma progression. OCT is arguably the most accurate test for diagnosing glaucoma. It uses light to create a detailed image of the optic nerve and retina. Pachymetry is a painless test that measures the thickness of the cornea with a small probe after numbing the eye with eye drops.
Knowing the thickness of the cornea helps the optometrist understand the pressure inside the eyes. The optometrist may also use a specialized contact lens to check if the drainage angle is open and wide or narrow and closed. If it's narrow and closed, watery fluid can block it and cause pressure to build up on the optic nerve. Normal-tension glaucoma can damage the optic nerve even when the eye's intraocular pressure (IOP) is considered normal. To diagnose this type of glaucoma, the optometrist will dilate the pupils with eye drops and then photograph the optic nerve with a digital camera or use other technologies such as OCT to map it.
Early detection is key to effectively controlling glaucoma, so it's important to have your eyes examined by an eye doctor if you have any risk factors for this condition, such as a family history of glaucoma. With careful examination of the optic nerve, an optometrist can help protect your eyes from vision loss.