Contact lenses will detect illness and deliver drugs, review paper predicts

The newly published paper, called ‘Contact Lens Technologies of the Future’, represents one of the most comprehensive reviews of advances to come in contact lenses, the paper’s authors said, adding that such developments will catapult the commonly used medical device to applications well beyond refractive error correction.

“There are a range of diverse technologies that are shaping the future of contact lenses, in some cases already showing their potential in late-stage development initiatives and even commercially available products,” said Lyndon Jones, director of the Centre for Ocular Research & Education (CORE) at the University of Waterloo in Canada.

He added: “Novel biomaterials, nanotechnology progress, unique optical designs, biosensing discoveries, antibacterial agents and even battery miniaturisation and power transfer are coalescing like never before. The next several years will see incredible advancements and growth for an expanded contact lens category.”

The paper explores several areas in which the authors expect innovations to make an impact. For example, biomarkers in the tear film will give rise to diagnostic contact lenses to help detect and monitor systemic and ocular diseases, including diabetes, cancer, and dry eye disease. Meanwhile, integrated circuit progress may give rise to in-lens intraocular pressure monitoring for glaucoma and even retinal vasculature imaging for early detection of diseases such as hypertension, stroke, and diabetes.

Ocular disease treatment and management may likewise benefit from progress in fluid dynamics, materials science, and microelectronics, according to the review, while dehydration-resistant materials combined with electro-osmotic flow and reactive oxygen species-scavenging materials – when integrated into lenses – could offer alternative dry eye disease therapies.

The paper also explained how liquid crystal cells could replicate the functionality of the pupil and iris arrangement, autonomously filtering incoming light to overcome physiological defects. Embedded, tuneable spectral filtering has the potential to mitigate colour vision deficiencies.

Drug-delivering contact lenses may offer more accurate dosing than traditional eye drops, increasing the residence time of a drug on the ocular surface with less exposure to elements such as blinking and non-productive conjunctival absorption, reducing the many known side effects of drugs, the review paper said. 

According to the researchers, these techniques and related advances will also open up opportunities for contact lenses as theranostics, the multi-disciplinary medical field that combines therapeutics and diagnostics. Uniting sensing technology and microfabrication, theranostic lenses would release appropriate therapeutics based on continuous monitoring inputs, replacing more invasive procedures.

While 'smart' lenses have become associated with on-eye head-up displays, the authors write that optical enhancements extend well beyond those manifestations. Meanwhile, customised optics could address aberrated eyes, with the front surface of a lens shaped to reduce measured aberrations based on each person’s unique corneal shape. Embedded microelectronics could also constantly monitor corneal gaze direction, controlling optical elements to address presbyopia in real-time.

Myopia control lenses are slowing axial growth in children, responding to one of the most pressing issues in eye health today. And optical and digital display discoveries hold the potential for assisting people who suffer from low vision – and then extend to the general population to replace or supplement traditional screens.

The paper concluded with an overview of packaging and storage case material and design developments that may offer improved hygiene and reduced wearer-induced contamination.