Online Eye Exams Have Arrived. But Are They Accurate?

When it comes to your vision, can a computer ever substitute for a doctor? (Gif: Tumblr)

Hate schlepping to the doctor to get a prescription for your glasses or contact lenses? There’s a new site for that.

Opternative allows you to take an eye exam using just your computer — at home. The site specifically conducts a refraction test (which measures a prescription for glasses or contacts) in 25 minutes. It’s not covered by insurance, but the price isn’t too steep: It’s $40 for a glasses or contacts prescription, or $60 for both.

According to the Opternative site, the company was co-founded by an entrepreneur and optometrist, who wanted to create a faster way for patients to get a refractive exam.

Here’s how it works: You answer a few questions about yourself, including your age (you have to be between the ages of 18 and 40), and then measure 10 feet away from your computer, where you’ll stand for the exam.

During the exam, you’re walked through visual tests of shapes, patterns, numbers, and letters, and use your phone to answer the questions. Once the test is complete, it’s sent to a licensed ophthalmologist in your state to review and give you a digital prescription within 24 hours.

Opternative is currently available in 32 states and will be available in 46 states by early next year. Co-founder Aaron Dallek tells Yahoo Health that the site has had more than 17,000 people sign up since its launch 70 days ago.

But can a computer evaluate your eyes as well as a real doctor?

It depends, Michelle Akler, MD, a board certified ophthalmologist at Akler Eye Center in Dearborn, Michigan, tells Yahoo Health.

She calls the concept of doing a vision test online “interesting” but says it doesn’t allow for comments from a patient like “it’s clearer but slightly doubled on the right,” which can also help with determining the right prescription. “I find the patient’s speed of answer and additional comments very helpful in arriving at the most optimal prescription,” she says.

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Albert Pang, O.D., a board-certified optometrist at Trinity Eye Care in Texas and a diplomate of the American Board of Optometry, tells Yahoo Health that he wouldn’t advise that people do this.

Pang points out that patients often don’t know what their eye problems are. While they may think they need glasses, the problem could be more complicated than that. “ A majority of [the issues] are caused by improper uses of their work environment or eye strain due to a faulty vision system,” he says. “Looking at an eye chart only involves testing the eye sight, it does not test the patients’ vision which involves how the eyes work together, how the eyes focus, and, above all, how the whole visual system works together.”

But Dallek notes that the test allows patients to provide commentary, which is “taken into consideration by the ophthalmologist when deciding the appropriate prescription or diagnosis.” He also points to a small, independent institutional review board-reviewed clinical trial conducted on 30 people by the company that found the results from using Opternative were statistically equivalent to those obtained by an refraction test done in a doctor’s office.

Renee Bovelle, MD, a board-certified ophthalmologist at Envision Eye & Laser Center tells Yahoo Health that there are certain nuances that can occur during an eye exam that won’t be detected by a computer such as lighting and squinting — both of which can alter your results.

Akler also points out that you can’t just take the test and get contact lenses for the first time, since you’d still need to be fitted by an optometrist or ophthalmologist. “Not doing so could result in contact lenses that do not fit properly and can increase the risk of corneal infection,” she says. “This is not a substitute for a discussion with an eye care professional about the appropriate contact lenses for you.”

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And, of course, a refraction test isn’t the same as an eye health test. Among other things, an eye health test, which is conducted at your doctor’s office, screens for glaucoma, cataracts, dry eyes, and diabetic eye disease.

But Dallek says that his service is designed to give patients an easy way to get a prescription between eye health exams, which they recommend patients do every two years. They also make sure patients follow guidelines from the American Academy of Ophthalmology of getting an eye health exam every five to 10 years by restricting them from taking the online exam more than four times in a five-year period without seeing an eye doctor.

Akler says it’s possible for the results of the test to be “fairly accurate” if the refraction is simple and you have no health or eye issues. There may be a subset of young, healthy patients with a straightforward prescription that this would help, she says, although she still recommends getting your exam with an eye doctor.

Adds Akler, “A computer is simply not a substitute for a doctor.”

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