The ‘air puff test’, or non contact tonometer, measures the pressure of fluid in the anterior segment of your eye. Eye pressure can be measured with several different instruments. The standard for measuring eye pressure is the Goldmann applanation tonometer which requires drops and uses a probe to touch the front of the eye. These tests are important as elevated eye pressure is the main cause of glaucoma, a degenerative disease of the optic nerve that may lead to blindness. Eye pressure testing will not reveal cataracts or many other eye diseases. It is still an important measure in evaluating eye health.
Using drops to dilate your pupils, then examining your lens with a slit lamp and ophthalmascope will show the doctor if you have any cataracts or retinal disease. By avoiding a real eye exam with either air or applanation tonometry and a careful slit lamp evaluation of your cornea and retina, you are missing the most important elements of a complete eye health evaluation.
These exams reveal many eye conditions that are sight threatening and many other ocular changes that may be life threatening. A virtual eye exam will tell you nothing about this and unfortunately gives the patient a false sense of security that everything is fine when it may not be. These tools have been developed over the last 150 years and have been indispensable in protecting the vision and saving the lives of millions of people.