Posted on

Why these tests?


How many times have you sat in a doctor’s office and thought to yourself, hmmm, I wonder what is going to happen next? Only to be told that you need another test.

I received an email from a patient the other day with the following question:

Doc, the last time I was at your office you said I had to do a Pachymetry test. Could you please explain it to me? I would like to know why I have to have it done and the effects if I don’t.{{more}}

This was my response:

If you are like most patients, you cringe at the thought of another test. All you want to do is get in and get out of the doctor’s office as fast as possible. Of course, that is possible when doing a routine eye examination. However, if you choose to do a comprehensive eye exam, which we recommend if you have not had one in over two years, then there are a battery of tests that help rule out defects and possible diseases.

Pachymetry is a test done in Ophthalmology to help in the diagnosis of Glaucoma and also for patients preparing to have LASIK surgery. An instrument called a Pachymeter measures the thickness of the cornea, using ultrasound. Research shows that people with thin corneas can have falsely low eye pressures, while people with thick corneas can produce falsely high eye pressures. This is very important because there might be people out there who do not have Glaucoma, but may be under treatment and likewise there are persons who have Glaucoma but are not under treatment.

People with the highest risk for Glaucoma are: people of African origin; family members of a Glaucoma patient; people over a certain age group; steroid users; people with injury to the eye; and people with elevated eye pressure. Other risk factors may include but are not limited to, Diabetes; Hypertension; High Myopia (nearsightedness); and a central corneal thickness of less than 0.5mm.

The fact that test was recommended means that you fall into several of these categories. Not only people with high eye pressure have Glaucoma, people with normal or low eye pressure can also develop Glaucoma. Detecting the disease early is crucial for stopping or slowing down its progression.

It should be noted that there is no single test that is 100% effective in determining whether one has Glaucoma or not. The diagnosis of the disease depends on many factors, some of which include the measurement of your Visual Acuity (evaluation of your central vision); Perimetry (visual fields-evaluation of your peripheral vision); Tonometry (measuring eye pressure); Ophthalmoscopy (evaluation of the optic nerve and retina); Gonioscopy (evaluation of the anterior chamber angle); Optic nerve imaging and Pachymetry (which measures the thickness of your cornea).

Regular eye examinations help in the early detection of Glaucoma. People at risk should check their eyes every year. Patients with already established Glaucoma should check their eyes every four months.

So, as you can see, comprehensive eye examinations do make a difference in ruling out early signs of disease. Statistics show that people who have regular comprehensive eye examinations are less likely to lose their vision. Don’t become one of those statistics. Check early, see clearly.

Have a great week.

Dr Kenneth Onu is a resident Consultant Ophthalmologist at the Beachmont Eye Institute/Eyes R Us Send questions to:
Tel: 784 456-1210