As summer vacation and the holiday season begin, many people are looking to shed their glasses with advanced laser vision correction procedures such as SMILE LASIK and SMILE Pro.
However, preoperative examinations can sometimes reveal an unexpected obstacle: severe astigmatism. Common enough to affect about 90% of myopia patients, astigmatism is a refractive error in which the cornea is distorted like a rugby ball, blurring focus and making objects appear doubled.
The problem is that correcting severe astigmatism with laser surgery alone, such as LASIK, LASEK or SMILE, requires removing 20% to 30% more corneal tissue than in cases of myopia alone. If the cornea becomes too thin, the risk of side effects rises, including dry eye syndrome and corneal ectasia, or keratoconus. Another option, phakic intraocular lens implantation, also has limitations: it requires an expensive toric ICL lens, takes more than a month to order, and can lose corrective effect if the lens rotates slightly inside the eye.
The safest way to overcome severe astigmatism is corneal incision astigmatism correction. This procedure does not remove tissue from the central cornea. Instead, it uses a fine ophthalmic knife to make a small incision in the peripheral cornea, adjusting the tension of the distorted cornea and restoring its round shape. Because the central cornea is left untouched, there is little risk of irregular astigmatism and fewer side effects.
Its value becomes even greater when combined with other vision correction procedures.
A representative example is the Super Save SMILE (SSVC) procedure, which our medical team published in the international journal Cornea. Even patients who cannot undergo SMILE because of severe astigmatism can first reduce their astigmatism with this correction procedure and then proceed with SMILE LASIK or SMILE Pro, cutting corneal ablation by as much as 52% compared with laser surgery alone.
Astigmatism correction is also an excellent alternative for patients undergoing phakic intraocular lens implantation (ICL). Instead of using an expensive toric lens, patients can first correct astigmatism with this procedure and then undergo standard ICL surgery. This simplifies the operation and lowers the financial burden. It also eliminates the risk of the lens rotating inside the eye and blurring vision again, making long-term vision much more stable. In addition, this procedure is useful for addressing residual astigmatism that can reduce visual quality before and after cataract surgery in older adults.
That said, although the principle of the procedure appears straightforward, the exact incision location and length must be determined before surgery to prevent undercorrection or overcorrection. Using advanced astigmatism-tracking equipment such as Callisto Eye is important, but so is the surgeon’s ability to feel and adjust corneal tension by hand. It is a highly specialized technique that requires extensive clinical experience and precise data accumulation.
The most absolute value in vision correction is safety. Rather than rushing to solve everything at once and damaging precious corneal tissue, the right approach is to preserve as much of the cornea as possible, even if it takes a little more time. That is the surest way to protect your eyes and enjoy the clearest summer possible.
Help from Jung Young-taek, hospital director at Jeonju Onnuri Eye Hospital
This article has been translated by GripLabs Mingo AI.
