According to the World Health Organization, cataracts are the leading cause of blindness worldwide, affecting around 65.2 million people. Cataracts are responsible for approximately 51% of blindness cases and are a major contributor to poor vision in both developed and developing countries. While cataracts cause 5% of blindness in developed nations, this number surges to over 50% in less privileged regions. Nearly 18 million people globally suffer from bilateral blindness due to cataracts, and they cause moderate to severe vision loss in 52.6 million individuals. The prevalence of cataracts in people aged 40 and older ranges from 11.8% to 18.8%.

Currently, there are no effective methods for cataract prevention or drug treatment. However, surgical removal of the opaque lens and the implantation of an intraocular lens (IOL) can restore vision in cataract patients. Cataract Laser surgery is the most common ophthalmic procedure performed worldwide, with more than 26 million surgeries conducted annually. As demographics change and medical services become more accessible, the volume of cataract surgeries is steadily increasing at a compound annual rate of 3.1%.

Evolution of Cataract Surgery

Cataract surgery has evolved significantly over the years, with standards continuously improving. From early intracapsular cataract extraction (ICCE) to extracapsular cataract extraction (ECCE) and the current phacoemulsification (PCS), the techniques and equipment have evolved. In developed countries, PCS is the mainstream method of cataract removal procedure. However, challenges persist in promoting PCS in developing countries, primarily due to the high cost of the procedure, a shortage of well-trained surgeons, and difficulties in maintaining advanced equipment. Therefore, small incision cataract surgery (SICS), an improved ECCE method, is emerging as a cost-effective alternative to PCS in less developed regions.

Premium Intraocular Lenses (IOLs)

Cataract surgery has witnessed continuous improvement in surgical equipment and techniques, making it one of the safest and most successful medical procedures globally. With advancements in living standards, new technologies such as microincision cataract surgery and premium IOLs have emerged. Cataract Laser surgery is transitioning from vision rehabilitation to vision improvement, with an emphasis on refractive surgery. This evolution has given rise to refractive cataract surgery (RCS) and the increased use of premium IOLs to meet the personalized needs of patients.

Multifocal IOLs have demonstrated superiority over monofocal IOLs in uncorrected distance visual acuity, with more than 90% of patients gaining independence from distant spectacles following multifocal IOL implantation. However, some patients report postoperative dissatisfaction, often due to residual refractive errors that account for nearly 64% of poor vision post-surgery. Among the various IOL types, multifocal IOLs comprise 6-31%, with optical aberrations, including glare and halos, being the primary source of issues.

A new category of IOLs, the extended depth-of-focus (EDOF) IOLs, aims to bridge the gap between monofocal and multifocal IOLs. EDOF IOLs enhance intermediate distance visual acuity and provide improved contrast sensitivity.

Surgery Technology Innovation

Beyond advancements in intraocular lens calculation and design, improvements in surgical techniques play a critical role in enhancing postoperative visual outcomes. Phacoemulsification has become the dominant cataract surgical technique due to its ability to provide better visual acuity and reduce complications. It has effectively reduced surgical incision size, astigmatism, postoperative inflammation, and posterior capsule opacification. Studies have shown that the reduction in incision size from 3.0 to 2.0 to 1.8 mm does not compromise surgical efficiency or safety, making SICS and MICS (Micro-Incision Cataract Surgery) equally viable options.

Femtosecond Laser-Assisted Cataract Surgery

While modern cataract removal procedure have made significant progress, postoperative complications such as corneal edema, macular edema, and inflammation still affect many patients. The demand for safer and more precise surgical procedures has led to the development of femtosecond laser-assisted cataract surgery (FLACS). This technology offers advantages in lens fragmentation, anterior capsulotomy, self-sealing corneal incisions, and astigmatism correction.

Femtosecond laser assistance ensures precise execution of each step, optimizing IOL positioning and refractive outcomes. Several meta-analyses and randomized clinical trials have shown that FLACS outperforms traditional PCS in terms of visual and refractive outcomes, endothelial cell preservation, and reduced corneal edema. It is considered a safer and more precise alternative to traditional cataract removal procedure.

Artificial Intelligence in Cataract Surgery

In recent years, artificial intelligence (AI) research in ophthalmology, particularly in machine learning and deep learning, has progressed rapidly. While AI has been used in glaucoma and retinal disorders, its application in cataract diagnosis is also gaining momentum. Deep learning has shown superiority in grading cataracts from slit lamp images compared to professional graders. However, AI's role in cataract laser surgery applications remains a topic of exploration, with the potential to improve patient care and outcomes.

The Future of Cataract Medication

Although cataract surgery remains the most effective treatment for cataracts, there is ongoing research into medications to prevent and treat cataracts. Oxidative stress plays a crucial role in cataract development, and antioxidants such as GSH, vitamin E/C, zeaxanthin, lutein, and carotenoids have shown promise in slowing down cataract progression. Some commercially available antioxidative drops have been applied to cataracts.

Recently, groundbreaking studies have identified potential compounds that can reverse cataract formation. Lanosterol, for instance, has shown the ability to delay and reverse lentic protein aggregation, opening new possibilities for cataract treatment. High-throughput techniques have facilitated the identification of synthetic lanosterol analogs with improved potency and efficacy in reversing lentic protein aggregation. While drug research for cataracts is ongoing, these anti-aggregation compounds offer hope for future cataract medication.

Conclusion

The field of cataract laser surgery is continuously evolving with advanced technologies, premium IOLs, innovative surgical techniques, and the introduction of AI. These developments promise to enhance patient outcomes and expand the scope of cataract treatment. Additionally, the potential for cataract medication is an exciting prospect that could reduce the need for surgical interventions in the future. The future of cataract treatment holds promise for improved patient care and a brighter outlook for those affected by this common vision impairment.