Corneal Microlens Removal & Trifocal IOL: Reversible Presbyopia Treatment

A corneal microlens, designed to correct presbyopia, proved easily removable during cataract surgery in a recent case study, offering a potentially reversible vision correction option. The procedure, presented at the European Society of Cataract and Refractive Surgeons winter meeting, involved successful explantation of the lens followed by implantation of a trifocal intraocular lens (IOL) in a patient who had developed cataracts. This suggests the microlens doesn’t damage the cornea and provides a pathway for future vision correction should a patient’s needs change.

Microlens Removal and Trifocal IOL Implantation

Pavel Stodulka, MD, PhD, detailed the case, explaining that the patient had enjoyed five years of spectacle independence with the CorVision corneal microlens (LinkoCare) in one eye before developing bilateral cataracts. Dr. Stodulka opted for a surgical plan that involved removing the microlens and replacing it with a trifocal IOL to restore the patient’s previous visual acuity. He initially expressed some concern about the procedure, given the lens’s extremely thin profile – just 20 µm – and the potential difficulty of accessing the original femtosecond laser-created corneal pocket.

“I was afraid I would not be able to open this old laser incision and safely enter the pocket with my instruments,” Dr. Stodulka told Healio. “And then, would I be able to take out this extremely thin piece of biosynthetic collagen? If I managed all that, what would be the corneal quality and the vision quality with that cornea and trifocal IOL?”

However, the explantation proved surprisingly straightforward. Dr. Stodulka was able to easily open the incision, access the pocket, and extract the lens after dividing it in half with micro-forceps. A video of the procedure demonstrated the lens drying and folding upon contact with air. The extracted lens was then sent to a laboratory in Sweden for analysis.

Corneal Integrity and IOL Compatibility

Post-explantation, the patient’s cornea remained clear, with only a visible, but unscarrred, pocket. Dr. Stodulka proceeded with cataract surgery and trifocal IOL implantation, utilizing the CAPSULaser (Excel-Lens) technology. He also implanted a capsular tension ring, a standard practice with trifocal IOLs. The patient achieved complete spectacle independence just nine days after the surgery.

“We were happy to see that this micro-implant is removable and reversible. You can take it out after 5 years … And a trifocal lens fits in without any modifications in IOL power calculation. We hit the target,” Dr. Stodulka stated. He anticipates the corneal pocket will become virtually invisible on slit lamp examination within weeks or months due to the absence of scarring.

Laboratory testing confirmed the integrity of the explanted lens, showing no changes in clarity, thickness, or shape. Previous research has indicated that the material used in the CorVision microlens bio-integrates well with the cornea, even allowing for corneal nerve growth. The implantation process, which involves creating a minor pocket without a flap, minimizes the risk of dry eye, according to Dr. Stodulka.

Understanding Corneal Microlenses and Presbyopia

Presbyopia, the age-related loss of near vision, affects nearly all adults over the age of 40. It occurs as the natural lens of the eye loses its flexibility, making it difficult to focus on close objects. The National Eye Institute provides comprehensive information on presbyopia, its causes, and available treatment options.

Corneal microlenses, like the CorVision lens, represent a relatively new approach to correcting presbyopia. These small lenses are implanted into a pocket created within the cornea, altering its shape to improve near vision. Unlike some earlier corneal inlay technologies, the CorVision lens doesn’t require the creation of a corneal flap, potentially reducing the risk of complications.

Implications for Future Vision Correction

This case study highlights the potential benefits of corneal microlenses as a reversible option for presbyopia correction. The ease of explantation and compatibility with subsequent IOL implantation suggest that this technology could offer patients greater flexibility in managing their vision over time. However, it’s important to note that this is a single case report, and further research is needed to confirm these findings in larger patient populations.

The success of this procedure also underscores the advancements in femtosecond laser technology and IOL implantation techniques. Premium IOLs, such as trifocal lenses, offer patients the potential for spectacle independence at all distances, but require careful planning and execution to achieve optimal outcomes.

What’s Next for Corneal Microlenses?

Further clinical trials are planned to evaluate the long-term safety and efficacy of the CorVision corneal microlens. Researchers will also investigate the potential for using this technology in combination with other vision correction procedures. The explanted lenses will continue to be analyzed to better understand their biocompatibility and long-term effects on the cornea. Ongoing surveillance and data collection will be crucial to refining surgical techniques and optimizing patient selection for this innovative approach to presbyopia correction.

Disclosures: Stodulka reports being a shareholder in Excel-Lens and LinkoCare.