Glaucoma, the leading cause of blindness, affects some 70 million people, including four million Americans. As Americans age, the problem is expected to worsen in the U.S. There's stronger hope of progress in the fight against glaucoma, thanks to funding from the Caltech Innovation Initiative, a philanthropically funded internal grant program designed to provide research funds to high-risk but potentially high-reward projects that could produce disruptive technologies with practical applications in the marketplace. With Caltech Innovation Initiative seed funds, Caltech electrical engineer Hyuck Choo is developing a device that could accelerate progress on glaucoma research in addition to helping patients monitor their own optical health.
The key research and clinical tool for glaucoma is intraocular pressure (IOP) monitoring. But presently available IOP monitoring technologies are so cumbersome and limited that researchers studying animal models have to use anesthesia and extreme care to achieve acceptable accuracies, and patients can only get periodic snapshots of their pressure at their doctor's office. So far, most approaches to this problem have focused on development of microelectronic implantable sensors, but the sensors are too big for more than 90 percent of the animal species used in glaucoma research. Glaucoma patients themselves may object to such large sensors (1–3 mm in diameter) because of their visibility and interference with eye function.
Choo has pioneered a new approach, using precise nanophotonic engineering to create an implantable IOP monitoring system 10 to 30 times smaller than previously used sensors. In the first year of Caltech Innovation Initiative support, his group has completed the first device simulations and designs, developed a fabrication process, and begun fabrication. They have also built a measurement setup and obtained initial measurements that correspond with their expectations.