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When Smartphones Do a Doctor’s Job

A simple, cheap way to measure eyesight may face resistance.
September 13, 2013

Vitor Pamplona isn’t a doctor. He’s not even an optician. He can’t write you a prescription for glasses, or sell you a pair. Still, he’s pretty sure he’s going to disrupt the $75 billion global eye-care market.

screen grab of EyeNetra app
Eye app: A smartphone displays a measurement of the refractive error of a person’s eyes.

At EyeNetra, the startup he cofounded, goofy curiosities like plastic eyeballs line the shelves, and a 3-D printing machine whirs in the background. It’s printing out prototypes of a device that will attach to your smartphone and, in a minute or two, tell you what kind of eyeglasses you need.

The device, called the Netra-G, is based on some clever optics and software Pamplona came up with—a way to measure the refractive error of the eye using a smartphone screen and an inexpensive pair of plastic binoculars. The whole setup might cost a few dollars to make. It does the job of a $5,000 instrument called an autorefractor.

More important, just about anyone could use it. That’s where the disruption comes in—and the trouble. Right now, only doctors or optometrists can prescribe glasses or contact lenses. Pamplona, a brash Brazilian programmer who arrived in the U.S. a few years ago, thinks that won’t always be the case. “We’re changing medicine by providing the user the right to measure themselves,” he says. “We see doctors as more of a coach.”

Mobile phones are giving rise to a new class of clip-on diagnostic devices that could challenge doctors’ monopoly on diagnosing disease, not just errors in vision. Since doctors’ fees account for over 20 percent of U.S. health-care spending—and fully 3 percent of the country’s GDP on their own—such devices could potentially slash costs as well.

eye netrax table

EyeNetra has received more than $2 million in financing from the outspoken Silicon Valley investor Vinod Khosla, who last year antagonized doctors by calling what they do “witchcraft” and predicting that 80 percent of their work diagnosing and prescribing could be done by machines.

Khosla’s investment fund is also backing several other similar ventures, including AliveCor (see “Your Heartbeat on an iPhone”), which sells a heart monitor that attaches to an iPhone, and Cellscope, a company developing a phone camera that could let parents diagnose a child’s ear infection (see “Parents Could Skip the Doctor’s Office with This Device”.)

Pamplona invented the Netra while studying in an MIT lab specializing in computational photography. That technology uses computers to bend the limits of traditional photography—it’s led to cameras that that see around corners or that can focus at every distance, all at once (see “Light-Field Photography”).

The prototype device he developed to measure how well your eye focuses light consists of a viewer that a user places against a smartphone screen. Spinning a dial yourself, you align green and red lines. From the difference between what you see and the actual location of the lines, an app calculates the focusing error of your eyes. It’s like a thermometer for vision.

Using the device, a person might figure out his or her prescription and then, from the very same app, order glasses from an online store like Warby Parker. The price of an eye exam and a new prescription can run from $50 to $150. Optometrists also make money selling glasses.

After running into Pamplona at a conference last year, Dominick Maino, an optometrist based in Chicago, wrote a column in his industry’s newsletter telling colleagues it was time to “panic … just a little.”

Maino thinks Netra can “give a good prescription, most of the time.” But an optometrist—there are 40,000 in the U.S.—looks at your eye health overall and can deal with complex cases. “He wants to put much more power into the hands of the individual, which isn’t a bad thing,” Maino says of Pamplona. “But you can’t write the doctor out of the equation. There’s a lot more to a great pair of glasses than an objective measure of refraction.

Euan Thomson, a partner at Khosla Ventures, says of all the challenges mobile-health companies must face, the most difficult “is going to be that act of diagnosis by the doc.” In the U.S., doctors usually don’t get paid unless they see a patient. “Payments are all based on patient visits,” he says. “Yet much of mobile health is around avoiding the need for patients to go in to the doctor.”

Because of such obstacles, Khosla’s firm has been advising its companies not to shoot directly for U.S. consumers, at least at first, and instead to work closely with doctors. EyeNetra, based outside Boston, has been testing its device in India, where it may prove easier to find a market. In India, about 133 million people are blind or can’t see well because they don’t have access to eye exams or glasses. What’s more, optometry isn’t regulated as heavily there as it is in the U.S.

However, Thomson says all Khosla’s mobile diagnostics companies, including EyeNetra and AliveCor, will eventually need to reach consumers directly, because that would give them access to millions or billions of electrocardiograms or glasses prescriptions. That could open new avenues for both medicine and marketing.

“What’s at the center of all this is the information, not the device,” says Thomson. The debate will be over who gets to interpret that information.

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