|Smart contact lens--Courtesy of Sensimed|
Increased intraocular pressure is part of the progression of glaucoma, which is a common cause of blindness. But it can be difficult for physicians to accurately track and measure intraocular pressure to chart the course of the disease and to help determine necessary treatment. Now, the FDA signed off on a smart contact lens system from Swiss startup Sensimed that can help doctors determine the best time of day to measure intraocular pressure.
The marketing allowance is via the regulator's de novo premarket review pathway, which is reserved for some low to moderate risk medical devices that do not have a substantial equivalent marketed device.
The Triggerfish system from Sensimed includes a one-time-use contact lens that is worn for 24 hours by a glaucoma patient. It's intended to help providers identify the best time of day to measure a particular patient's intraocular pressure (IOP), the increase of which is associated with escalating damage to the optic nerve. A recent study using the device suggested that time of day for pressure changes is associated with disease progression.
|The Sensimed Triggerfish sensor (1), its antenna (2), the cable (3) through which data is transmitted to the portable recorder (4)--Courtesy of Sensimed|
In addition to the lens itself, Triggerfish includes an adhesive antenna, which is worn around the eye during that period and transmits the data through a cable from the antenna to a portable recorder that's worn around the patient's neck. Data is transferred via Bluetooth from the recorder to software installed on a healthcare provider's computer. Triggerfish already has a CE mark in Europe.
"The Triggerfish gives the clinician 24-hour continuous monitoring of changes in IOP patterns that otherwise could not be obtained," said Dr. William Maisel, acting director of the Office of Device Evaluation in the FDA's Center for Devices and Radiological Health, in a statement. "This information can help determine the most critical time of day for the clinician to measure the patient's IOP."
In a recent study, Columbia researchers tested the lenses on 40 patients aged 40 to 89 being treated for open-angle glaucoma, the most common form of the disease. Over a period of two years, the scientists performed at least 8 standard visual field tests on them. Half were classified as having slow disease progression with the other half having fast disease progression.
They found that those patients classified as having faster glaucoma progression tended to have steeper pressure spikes overnight and a greater number of peaks in pressure. So, the lenses could prove useful not only for more quickly distinguishing between patients with faster and slower glaucoma progression, as well as for the individual evaluation of the efficacy of a given treatment.
In its statement, the FDA stressed that the system is only useful to determine the range of time during the day that eye pressure may be increasing. It noted that it does not actually measure intraocular pressure and that it is not intended for diagnostics or treatment. The agency found it effective in "showing an association between the Triggerfish device output and IOP fluctuation" and signed off on its use in adults who are age 22 or older under the direction and supervision of a healthcare provider.
Ultimately, Triggerfish could offer more effective monitoring of glaucoma patients and help influence treatment decisions for individual patients.
- here is the FDA announcement