An innovative contact lens for glaucoma

August 13, 2014
An innovative contact lens for glaucoma
Credit: © 2014 Reto Duriet

EPFL researchers have participated in the development of a contact lens for the early detection of glaucoma. Clinical trials are being conducted at the CHUV.

Glaucoma, which results from excessive pressure in the eye, is the second leading cause of blindness worldwide, after cataracts. Painless and invisible, this insidious disease is often detected too late by doctors, once the optic nerve has already been damaged.

In Neuchâtel, the startup Tissot Medical Research (TMR) commissioned researchers from EPFL and Haute Ecole Arc to develop a single-use contact lens capable of measuring continuously for 24 hours. This could track day and night-a minor revolution for specialists.

Most ophthalmologists use a technique called Goldmann Applanation Tonometry, which consists of applying a kind of cone with the tip flat against the cornea to measure intraocular pressure. While very accurate, this measure can only be done on an ad hoc basis, using an expensive camera in a doctor's office. However, peaks in pressure often occur at night or in the early morning, outside normal consultation hours. Under these conditions, it is difficult to spot abnormal rates of pressure.

A blink, a measure

Composed of silicone, these smart lenses from Tissot Medical Research perform measurements at each blink of the eye, using the same principle as the traditional method. Each lens is equipped with a protuberance that presses against the cornea with each blink. In this bump within the lens, a rigid ring contains a capacitive sensor formed by electrodes. "When the eyelid closes, the bump puts pressure on the cornea, causing the electrodes to come closer together," explains Luc Tissot, founder of TMR. The distance between the electrodes therefore indicates the rate of intraocular pressure. "It's a bit like when you press a balloon to estimate the amount of air inside," illustrates Alexis Boegli, of the Electronics and Signal Processing Laboratory at EPFL (ESPLAB).

Small antennas attached to the patient's glasses regularly capture information collected by the lens. "At night, it might be possible to wear an eye mask, for comfort," says Alexis Boegli. The glasses are connected by a wire to a small portable box that is the size of a wallet. Patients can thereby go about their business while wearing the device.

"After 24 hours, ophthalmologists plug a USB key into the housing and analyze the results on a computer. It is quite possible to send data directly to a smartphone, but experts adhere strictly to the confidentiality of medical information," says Pierre-André Farine, Director of ESPLAB. The results are in turn provided in the nearest millimeter of mercury (mm Hg), allowing to identifying the precise moments of the pressure peaks.

Improving the treatment of glaucoma

Not content to merely detect glaucoma, the new smart lens should also make it possible to measure the biomechanical properties of the cornea, and to adapt the treatment of this disease. "Clinical trials are being conducted at the Ophthalmic Hospital of CHUV. These to gauge the comfort of the device, and also test the measurement system", explains Dr Katia Tissot, the medical manager for the society.

It is worth noting that the lens from Tissot Medical Research is not the only one on the market. Another Swiss company, Sensimed, an EPFL start-up, also has developed a for the detection of glaucoma. However, it uses a different technology which analyzes changes in circumference of the cornea.

The lens from Tissot Medical Research should be commercially available by the end of 2015.

Explore further: Researcher taking the pressure off glaucoma diagnosis

Related Stories

Researcher taking the pressure off glaucoma diagnosis

June 9, 2014
(Medical Xpress)—Glaucoma represents the second-leading cause of irreversible blindness in the world's aging population, with 400,000 Canadians and 67 million people worldwide suffering from the condition.

Innovative drug-dispensing contact lens delivers glaucoma medication continuously for a month

December 9, 2013
For nearly half a century, contact lenses have been proposed as a means of ocular drug delivery that may someday replace eye drops, but achieving controlled drug release has been a significant challenge. Researchers at Massachusetts ...

Novartis to use Google technology for eye care

July 15, 2014
Swiss drug developer Novartis will team with technology giant Google to develop a "smart" contact lens that could improve some eye conditions or help diabetics manage their disease.

Contact lens sensor measures 24-hour intraocular pressure

August 15, 2012
(HealthDay) -- A contact lens sensor (CLS) provides safe and tolerable 24-hour monitoring of intraocular pressure (IOP) patterns in patients with or suspected of having glaucoma, according to research published online Aug. ...

Recommended for you

Scientists regenerate retinal cells in mice

July 26, 2017
Scientists have successfully regenerated cells in the retina of adult mice at the University of Washington School of Medicine in Seattle.

Genome editing with CRISPR-Cas9 prevents angiogenesis of the retina

July 24, 2017
A research team from the Schepens Eye Research Institute of Massachusetts Eye and Ear has successfully prevented mice from developing angiogenesis of the retina—the sensory tissue at the back of the eye—using gene-editing ...

Too little vitamin D may hinder recovery of injured corneas

July 24, 2017
Injury or disease in combination with too little vitamin D can be bad for the window to your eyes.

Combination of type 2 diabetes and sleep apnoea indicates eyesight loss within four years

July 4, 2017
Research led by the University of Birmingham has discovered that patients who suffer from both Type 2 diabetes and obstructive sleep apnoea are at greater risk of developing a condition that leads to blindness within an average ...

Nearly 60% of pinkeye patients receive antibiotic eye drops, but they're seldom necessary

June 28, 2017
A new study suggests that most people with acute conjunctivitis, or pinkeye, are getting the wrong treatment.

Magnetic implants used to treat 'dancing eyes'

June 26, 2017
A research team has successfully used magnets implanted behind a person's eyes to treat nystagmus, a condition characterised by involuntary eye movements.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.