How Eye Doctors Test for Glaucoma

Regular and comprehensive eye exams are essential for protecting eye health. Early detection will help protect your vision from damage due to glaucoma. Eye exams include several tests to detect signs of glaucoma. Having your eyes examined regularly will allow the doctors to screen for glaucoma. 

Every person should have a baseline eye screening for glaucoma when they turn 40. This is usually the age at which changes in vision and other signs of eye disease start to occur. It is necessary to understand how eye doctors test for glaucoma. 

Tonometry Test

A comprehensive glaucoma exam will include a tonometry test. The test checks the inner eye pressure. During the test, the doctor will numb the eye using eye drops. The doctor will then use a device known as a tonometer to measure the pressure on the inner eye. 

A tiny device or warm air applies some pressure to the eye. A diagnosis for glaucoma occurs when the pressure exceeds the normal range. The normal range is between 12 to 22 millimeters of mercury.

Ophthalmoscopy Test

Doctors conduct ophthalmoscopy or dilated eye exams during glaucoma screening. The test helps examine the color and shape of the optic nerve. The diagnostic procedure allows the eye doctor to examine the optic nerve for signs of glaucoma damage. The doctor applies eye drops to dilate the pupil. 

Using a small device that lights and magnifies the optic nerve, the doctor can see through the eye. If the optic nerve appears unusual or if the intraocular pressure is not within normal range, additional testing may be done.

Perimetry Test

A perimetry or visual field test confirms a suspected glaucoma diagnosis. The test helps examine the patient’s field of vision. If the patient’s pressure is high and the optic nerve looks unusual, a field test will be conducted. The test produces a map of the patient’s complete visual field. 

The test will help determine if the vision is affected by glaucoma. During the test, the patient should look at a light spot straight ahead. The spot is moved to different parts of the patient’s peripheral vision, helping draw a map of the vision. 

Gonioscopy Test

The gonioscopy test helps examine the part of the eye where the iris and the cornea meet. The diagnostic test helps determine if the angle is wide and open or narrow and closed. During testing, eye drops will numb the eyes. 

The doctor places a hand-held contact lens gently on the eye. The lens has a mirror, allowing the doctor to see the angle and determine if it is blocked or closed (angle-closure glaucoma). If the angle is wide and open, it is a possible sign of open-angle glaucoma. 

Pachymetry Test 

A pachymetry test helps examine the thickness of the eye cornea. The cornea is the clear part of the eye. The doctor places a pachymeter probe in front of the eye to measure the cornea thickness. Corneal thickness can affect eye pressure readings. The measurement will allow the doctor to understand the IOP reading and develop a treatment plan. 

To find out more on how eye doctors test for glaucoma, visit Perceptions Eye Health & Wellness at our office in Southport, North Carolina. You can call (910) 400-1215 today to schedule an appointment.