Stanford Biodesign fellows are testing two tiny devices that stimulate natural tear production. The technologies deliver micro-electrical pulses to the lacrimal gland.

One model is inserted into the mucous membrane in the nasal cavity, and the other is inserted under the skin below the eyebrow. Tear delivery rates can be adjusted manually with a wireless controller.

“Initially, we envisioned a large implanted device with a wire coming up inside the neck, similar to a pacemaker,” said Michael Ackermann, PhD, and a former Stanford Biodesign fellow. “We took it to eye specialists, who said, ‘That is never going to happen.’”

So they went back to the drawing board and built several versions of a much smaller model out of plastic and clay. They took these prototypes back to the eye specialists, who thought the devices, when actually made, could be injected under the eyebrow with a large-gauge needle in a doctor’s office.