CONTACT LENSES (CLs) have emerged as powerful tools capable of addressing challenges beyond vision correction.1 Advances in biomaterials, sensor technology, and nanotechnology are driving the development of CLs for diagnosing systemic and ocular diseases, delivering topical drugs, and enabling novel imaging applications.2,3 This article explores the key advancements shaping the future of CLs, focusing on their roles in diagnosing disease, delivering drugs, and providing cutting-edge imaging and augmented reality (AR) solutions, providing insight into a future in which CLs transcend their original purpose.
Much of the technology behind the development of these so-called “smart” CL platforms is driven by the rapid developments in the wearable biosensor market.4,5 The global market for wearable health devices, predicted to reach $30 billion by 2026, underscores the demand for such innovations. However, challenges remain in miniaturizing electronics, ensuring biocompatibility, and maintaining power efficiency.
Conventional batteries cannot be integrated with a smart CL, as those batteries are large and inflexible, produce heat, have a limited lifespan, and use toxic electrolytes.6,7 One intriguing powering option is a technology in which a glucose-based coating reacts with the Na+ and Cl- ions in the tear film surrounding it to generate electricity and power a circuit.8
CLs for Systemic Disease Diagnosis
Advances in biosensing technology have enabled the integration of diagnostic capabilities into CLs.1 They are emerging as a promising platform for noninvasive biosensing of tear fluid biomarkers, including glucose, lactate, matrix metalloproteinases, and cancer.9,10
The detection of glucose in the tear film to diagnose diabetes has been a focus for several research groups, and previous studies have shown that there is a strong correlation between tear and blood glucose levels (R² > 0.8),11 offering a noninvasive alternative to traditional blood-based measurements. Another promising biomarker is Substance P, which correlates with diabetic peripheral neuropathy. By analyzing its concentration in tears, these lenses may help identify the early-stage complications of diabetes.12
Ocular Disease Diagnosis and Monitoring
Smart CLs equipped with continuous monitoring systems are transforming the management of ocular diseases. Diagnosis of glaucoma is a primary focus. A commercially available CL, embedded with a strain gauge, provides 24-hour intraocular pressure (IOP) monitoring by measuring corneal curvature changes (Figure 1).13-15 Such data enable early detection and personalized treatment.
Smart CLs are also being developed to monitor dry eye disease (DED) using biomarkers, including tear osmolarity and inflammatory cytokines (eg, TNF-α, IL-6).16 Additional capabilities, such as corneal temperature measurement and integrated pulse oximetry, promise to enhance the detection and management of a wide variety of ocular conditions.1,17,18
Drug Delivery via CLs
Topical eye drops dominate ocular drug delivery but suffer from poor bioavailability, with less than 5% of the drug instilled reaching the target tissue.19 CLs soaked or embedded with drugs offer a sustained-release mechanism, improving therapeutic efficacy.1,20,21
While commercially available CL materials can uptake and release topical pharmaceutical agents, their release rate is too rapid to make them a viable option for extended drug delivery.1,22,23 Methods such as molecular imprinting, nanoparticles, impregnated polymer films, vitamin E diffusion barriers, and surface printing have been developed to control drug release from lenses.1,24-26 Potential applications include short-term therapies for microbial keratitis and corneal abrasions and longer-term treatments for glaucoma and ocular allergies.1,27-29 Scleral lenses with posterior drug reservoirs to deliver various drugs, including bevacizumab and cyclosporine, further expand their therapeutic potential in diseased eyes that have irregular corneas.30-32
Despite promising results, commercialization faces hurdles, including ensuring consistent drug release profiles and overcoming various regulatory challenges.1,33,34
3D Printing and CLs
3D printing is transforming the development of unique CLs by enabling precise customization, rapid prototyping, and advanced material applications.35,36 Researchers are utilizing biocompatible materials and high-resolution printing techniques to fabricate lenses tailored to individual eye shapes and to incorporate drugs.36-41
Additionally, 3D printing allows for the integration of smart features, such as biosensors that monitor IOP or detect biomarkers for ocular diseases, offering potential breakthroughs in personalized eye care.37,42 As research advances, 3D-printed CLs could revolutionize ophthalmology by providing customized solutions that improve vision correction and diagnostic capabilities.
CLs for Imaging and Optical Enhancements
Smart CLs are poised to revolutionize AR and virtual reality technologies.1,43-45 Various companies are developing AR-enabled lenses that provide a seamless digital overlay within the wearer’s field of view. Review of the patent literature describes applications ranging from navigation aids to enhanced training environments. CLs also hold potential for low-vision rehab through magnifying optics, facial recognition, and zooming capabilities.1 By integrating mini cameras and motion sensors, these lenses could support visually impaired individuals in performing daily activities independently.
AR CLs are being further explored for military and surgical applications, in which heads-up displays provide real-time data without obstructing the wearer’s vision. However, challenges include ensuring lightweight power sources, heat dissipation, and user comfort.
Artificial Intelligence and CLs
Artificial intelligence (AI) enhances the functionality of CLs by analyzing collected data in real time. AI-driven platforms can evaluate meibography images for DED, assess tear film stability, analyze biomarkers, and predict corneal disease severity.46-52 This synergy between smart lenses and AI algorithms allows for personalized treatment and disease management. Furthermore, AI integration enables advanced fitting methods for keratoconus and orthokeratology lenses, predicting lens decentration and its impact on higher-order aberrations.53,54
As AI continues to evolve, it will play a pivotal role in automating diagnostic processes, improving patient outcomes, and advancing lens design.
Challenges and Future Directions
Potential applications of CLs are vast, but several challenges must be addressed to realize their full potential.3,43,55Biocompatibility and comfort remain critical to ensuring widespread adoption. Integrating complex electronics into soft materials poses additional technical hurdles, including power supply and data transmission. Regulatory approval processes are another bottleneck, requiring robust clinical trials to validate safety and efficacy. Collaboration between engineers, clinicians, material scientists, and regulatory agencies are essential to overcoming barriers. Novel applications need to be prescribed or they will be commercial failures.
In 2024, two highly innovative CLs—a photochromic lens and the first drug-delivering lens that delivered a topical antihistamine—were discontinued due to manufacturing challenges, regulatory hurdles in certain countries, and low adoption, despite years of development and significant investment.29,56
From diagnosing systemic and ocular diseases to delivering drugs and enhancing vision through AR, the possibilities are numerous and transformative. Advances in biomaterials, sensor technology, and AI are driving this evolution. By embracing innovations, clinicians can unlock the full potential of CLs.
References
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