Types of Lasik Surgery

Introduction

LASIK (Laser-Assisted in Situ Keratomileusis) surgery has transformed the lives of millions suffering from refractive errors like myopia (nearsightedness), hyperopia (farsightedness), and astigmatism. It is a type of refractive eye surgery that reshapes the cornea to allow light entering the eye to be properly focused onto the retina, resulting in clearer vision. Over the past two decades, advancements in LASIK techniques have given rise to several types of procedures, each designed to cater to different corneal conditions and patient profiles. Understanding the types of LASIK Surgery can help patients and ophthalmologists determine the most suitable technique for effective results.

Types of LASIK Surgery

1. Traditional LASIK
   This is the most commonly performed LASIK procedure and involves creating a thin flap on the cornea using a mechanical microkeratome blade. Once the flap is lifted, an excimer laser is used to reshape the cornea. After reshaping, the flap is repositioned without the need for stitches. Traditional LASIK is often suitable for patients with common refractive errors and healthy corneas. However, it may not be ideal for those with thin corneas or other abnormalities, as it involves mechanical blade usage.
2. Femtosecond LASIK (All-Laser LASIK or Blade-Free LASIK)
   Femtosecond LASIK replaces the mechanical blade with a femtosecond laser to create the corneal flap. This technique provides greater precision in flap creation, minimizing complications and improving safety. The use of two lasers one for flap creation and another for reshaping gives surgeons more control over the procedure. This type of LASIK is especially beneficial for patients with thin or irregular corneas where precision is critical.
3. Custom LASIK (Wavefront-Guided LASIK)
   Custom LASIK uses advanced wavefront technology to map the eye’s unique imperfections before surgery. This detailed map guides the eye laser to correct not only common vision problems but also higher-order aberrations that traditional LASIK cannot address. Custom LASIK improves the quality of vision, particularly in low-light conditions, and reduces the risk of side effects like glare or halos. It is best suited for patients who desire a more personalized and refined correction of their vision.
4. Topography-Guided LASIK
   This newer technique utilizes corneal topography data to correct irregularities on the surface of the cornea. Unlike wavefront-guided LASIK, which focuses on the entire optical system, topography-guided LASIK specifically targets surface imperfections. It’s ideal for patients with highly irregular corneas due to conditions like keratoconus, corneal scarring, or previous unsuccessful eye surgeries. This method enhances visual outcomes in complex cases where standard techniques may not yield optimal results.
5. Contoura Vision LASIK
   Contoura Vision is an advanced version of topography-guided LASIK, approved by the FDA, and is one of the most precise LASIK treatments available today. It not only corrects refractive errors but also addresses corneal asymmetry to improve visual sharpness beyond 20/20 in some cases. Contoura Vision provides personalized treatment plans based on over 20,000 data points from the cornea, making it highly sophisticated. This technique is ideal for patients who want high-definition vision with minimal risk of side effects.
6. SMILE (Small Incision Lenticule Extraction)
   Though not technically LASIK, SMILE is often included under the broader category of laser vision correction surgeries. Instead of creating a flap, the surgeon uses a femtosecond laser to create a small lens-shaped disc (lenticule) within the cornea, which is then removed through a small incision. SMILE reduces the chances of dry eyes and flap-related complications, making it ideal for patients with active lifestyles or dry eye tendencies. However, SMILE currently treats only myopia and astigmatism, not hyperopia.
7. Epi-LASIK
   Epi-LASIK is a surface ablation technique that lies somewhere between PRK and LASIK. Instead of creating a corneal flap, a special device gently lifts the thin outer layer of the cornea (epithelium), and then the excimer laser reshapes the underlying corneal tissue. The epithelium is either replaced or allowed to regenerate naturally. Epi-LASIK is suitable for patients with thin corneas, high refractive errors, or those involved in contact sports where flap dislocation is a concern. Recovery is longer than traditional LASIK but provides comparable results.
8. LASEK (Laser-Assisted Subepithelial Keratectomy)
   Similar to Epi-LASIK, LASEK involves preserving and repositioning the epithelium after the laser reshapes the cornea. The difference lies in how the epithelial layer is treated. In LASEK, alcohol is used to loosen the epithelium, making it easier to lift. This technique is useful for patients with flat or thin corneas and those at high risk of trauma. It offers similar visual outcomes to LASIK but with slower healing and more postoperative discomfort.
9. PRK (Photorefractive Keratectomy)
   PRK is the predecessor of LASIK and is still widely used today, especially for patients who are not ideal LASIK candidates. In PRK, the epithelium is completely removed and discarded, and the laser reshapes the cornea. The epithelium then regrows naturally over a few days. PRK avoids the creation of a flap, making it ideal for patients with very thin or irregular corneas. Recovery takes longer and involves more discomfort, but the long-term results are similar to LASIK surgery.

Conclusion

The landscape of LASIK surgery and laser eye surgeries has evolved significantly, offering patients a wide range of options tailored to their specific eye conditions and lifestyles. From traditional flap-based LASIK to blade-free precision with femtosecond lasers and customized procedures like wave front and topography-guided LASIK, the choices are more refined and patient-centric than ever before. Techniques like SMILE and surface ablation methods such as PRK and LASEK provide alternatives for those not suitable for traditional LASIK due to anatomical or occupational reasons.

Choosing the right type of LASIK surgery involves a detailed eye examination and consultation with an experienced ophthalmologist. Factors such as corneal thickness, shape, degree of refractive error, and personal vision goals all influence the decision-making process. With proper evaluation and the right surgical technique, LASIK can offer excellent, long-lasting visual outcomes, reducing or even eliminating the need for glasses or contact lenses. Understanding these types not only empowers patients to make informed choices but also helps set realistic expectations for their vision correction journey.