Introduction
When patients begin researching LASIK, they quickly encounter a landscape of overlapping terminology: bladeless LASIK, wavefront-guided LASIK, custom LASIK, topography-guided LASIK, iLASIK, Z-LASIK — and then related procedures like PRK, LASEK, and SMILE. The proliferation of branded names and technical terms can make it genuinely difficult to understand how procedures differ and which type might be most appropriate for a given patient.
Clarity on this topic matters for two reasons. First, the specific procedure type and treatment profile has real implications for outcomes — particularly for quality-of-vision outcomes such as contrast sensitivity and nighttime glare performance. Second, understanding the terminology allows patients to have more substantive conversations with their surgeon during the consultation rather than simply accepting a recommendation without context.
The LASIK Surgery Awards program evaluates the range of procedure types offered at recognized practices, because practices limited to a single procedure type cannot always provide the most appropriate care for every patient they evaluate. This page explains each major procedure category in plain terms: what distinguishes it from the alternatives, what clinical evidence supports it, and who it is best suited for.
Section 1: The LASIK Procedure Family — What All Types Have in Common
The Shared Foundation Before the Distinctions
All LASIK procedures share a fundamental architecture: a flap is created in the anterior cornea, the underlying stromal tissue is reshaped using an excimer laser to correct the refractive error, and the flap is repositioned over the treated surface to heal. This basic structure distinguishes LASIK from flap-free procedures (PRK, LASEK, SMILE), which are related but technically distinct.
Understanding this shared architecture is important because it means that all LASIK variants share certain properties: the relatively rapid visual recovery compared to surface ablation procedures, the absence of surface epithelial disruption, and the presence of a permanent stromal pocket (the flap interface) that never fully reseals to original strength.
The variations among LASIK types occur in two dimensions: how the flap is created, and what kind of treatment profile is delivered by the excimer laser. These two dimensions are independent — any flap creation method can be combined with any excimer treatment profile.
Section 2: Flap Creation Methods — Blade vs. Bladeless
Microkeratome LASIK and Femtosecond LASIK
Traditional LASIK With a Microkeratome
The original LASIK flap creation method uses a microkeratome — a precision surgical instrument with an oscillating blade that passes across the corneal surface under controlled suction, creating a thin circular flap. Microkeratome technology has been refined over 30 years of clinical use and produces excellent results in skilled hands.
The advantages of the microkeratome approach include speed of flap creation (typically under 10 seconds), a well-established body of outcomes data, and cost efficiency that can make the procedure more accessible at price-conscious practices. Limitations include somewhat less precision in flap thickness consistency compared to femtosecond lasers, greater vulnerability to unexpected anatomy variations (particularly flat or steep corneal curvatures), and the occasional complication of incomplete or free caps.
Microkeratome LASIK is still widely performed and appropriate in many clinical contexts, particularly at practices with surgeons who have extensive experience with specific instruments.
Bladeless (Femtosecond) LASIK
Femtosecond LASIK — marketed under brand names including IntraLase, iLASIK, Z-LASIK, VisuMax, and FS200 — uses an ultrashort-pulse laser instead of a mechanical blade to create the corneal flap. The femtosecond laser delivers thousands of precise pulses at a programmed depth within the corneal stroma, creating microbubbles that coalesce into a separation plane. The result is a flap with exceptional thickness consistency, customizable architecture, and a smoother stromal bed than most microkeratome-created flaps.
Published comparative studies demonstrate that femtosecond flap creation is associated with lower rates of flap thickness variability, lower incidence of free caps, and superior flap architecture compared to microkeratomes in most studies. Visual outcomes in large clinical series are excellent, and the approach is now the standard at most leading refractive practices.
The primary limitation of femtosecond flap creation is a phenomenon called transient light sensitivity syndrome (TLSS) — a specific post-operative sensitivity to bright light that occurs in a small percentage of patients in the first week after surgery and is believed to be related to the photochemical effect of the femtosecond pulses. It is typically self-limited and responds to corticosteroid treatment.
The “bladeless LASIK” marketing category encompasses any procedure using femtosecond flap creation, regardless of which excimer treatment profile is used. When a practice advertises bladeless LASIK, clarify which femtosecond platform is used and which excimer treatment is planned.
Section 3: Excimer Treatment Profiles — Standard, Wavefront-Guided, and Topography-Guided
What the Laser Actually Does to the Cornea
The excimer laser treatment profile determines what shape is programmed into the cornea during the ablation phase. This is where the most clinically meaningful distinctions between LASIK types occur.
Standard (Conventional) LASIK
Standard LASIK corrects the sphere and cylinder components of the patient’s refractive error — the information captured in a standard glasses prescription. It uses a population-averaged ablation algorithm that has been validated across large patient populations and produces excellent outcomes for straightforward prescriptions.
The limitation of conventional treatment is that it does not account for the patient’s individual higher-order aberrations — the complex optical irregularities beyond sphere and cylinder that affect visual quality. For patients with significant higher-order aberrations, conventional treatment may not achieve the same quality-of-vision result as aberration-specific treatments.
Wavefront-Guided LASIK (Custom LASIK)
Wavefront-guided LASIK — marketed under names including CustomVue, VISX STAR S4, and WaveLight Allegretto treatments — uses aberrometry data from a wavefront sensor to generate a highly individualized treatment profile that corrects both the standard prescription components and the patient’s unique higher-order aberrations.
FDA clinical trials comparing wavefront-guided to conventional LASIK demonstrated statistically significant improvements in uncorrected visual acuity and a reduction in quality-of-vision complaints (halos, glare, contrast sensitivity loss) with the wavefront-guided approach. Wavefront-guided treatments are now considered the standard of care at leading practices for patients with measurable higher-order aberrations.
The practical benefit of wavefront-guided treatment is most pronounced in patients who had significant pre-operative higher-order aberrations, those with large treatment zones, and those in professions requiring excellent low-contrast or night vision performance.
Topography-Guided LASIK
Topography-guided LASIK uses detailed corneal topography data — rather than wavefront data — to plan an ablation that normalizes the corneal surface shape while correcting the refractive error. This approach is particularly valuable for patients with irregular corneal topography that would compromise the result of a conventional or wavefront-guided treatment.
The Contoura Vision system (WaveLight/Alcon) received FDA approval for topography-guided LASIK in 2015. Published clinical trials demonstrated that topography-guided LASIK produced outcomes superior to wavefront-guided LASIK in the specific outcomes of proportion of patients achieving 20/20 or better and reduction of higher-order aberrations. For patients with normal corneas, the advantage of topography-guided over wavefront-guided treatment may be modest; for those with pre-existing surface irregularities, the benefit can be more significant.
See LASIK Technology and Innovation in Top Practices for a detailed examination of the platform technology that delivers these treatment profiles.
Section 4: Related Refractive Procedures — Beyond the LASIK Family
PRK, LASEK, SMILE, and ICL Explained
The LASIK family of procedures represents the most common approach to laser vision correction, but several alternative procedures are frequently discussed — and in certain patient populations, are superior to LASIK.
PRK (Photorefractive Keratectomy)
PRK was the original laser vision correction procedure, predating LASIK by several years. In PRK, the surface epithelium is removed (by gentle scraping, alcohol application, or a laser), the excimer laser is applied directly to the anterior corneal surface, and the epithelium is allowed to regenerate over the following days under a bandage soft contact lens.
PRK eliminates all flap-related complications because no flap is created. It preserves more corneal strength because the anterior stroma — the biomechanically strongest zone — is not disrupted by flap creation. And it allows treatment of patients with corneas too thin for LASIK (because no flap tissue needs to be accounted for in the residual bed calculation).
The trade-off is recovery: PRK patients experience a more prolonged and uncomfortable healing period than LASIK patients. Surface healing takes four to seven days, during which vision is blurred and significant discomfort is common. Full visual recovery to the final outcome takes three to six months rather than the days to weeks seen with LASIK.
PRK is the preferred procedure for patients in contact sports, military service (particularly aviation), and active duty law enforcement; for patients with thinner corneas; and for many patients with dry eye concerns. For detailed guidance on which patients are better served by PRK than LASIK, see LASIK Candidacy: Who Qualifies for the Procedure.
LASEK and Epi-LASIK
LASEK (Laser Epithelial Keratomileusis) is a surface ablation technique that attempts to preserve the epithelial sheet during its removal and replace it after laser application. Epi-LASIK uses a specialized epithelial separator to create an epithelial flap. Both are variations of PRK with comparable outcomes but slightly different surgical mechanics that may offer advantages for specific patient presentations.
SMILE (Small Incision Lenticule Extraction)
SMILE represents a fundamentally different technology platform from LASIK or PRK. A femtosecond laser is used to create two planes of cuts within the corneal stroma, carving out a lens-shaped disc of tissue called a lenticule. The lenticule is then removed through a small peripheral incision (typically 2 to 3mm), eliminating both the LASIK flap and the surface ablation of PRK.
SMILE offers several potential advantages: no flap-related complications, better preservation of anterior corneal biomechanical strength than LASIK, lower rates of post-operative dry eye compared to LASIK (due to preservation of more anterior corneal nerve density), and no suction loss risk during the treatment delivery phase.
SMILE is FDA-approved for myopia and myopic astigmatism in the United States. Current limitations include the inability to treat hyperopia, somewhat less ability to incorporate higher-order aberration correction into the treatment profile compared to wavefront-guided LASIK, and a learning curve that means outcomes in less experienced hands may not yet match those reported in high-volume published series.
SMILE is offered at an increasing number of leading refractive practices, and award-worthy surgeons who offer both LASIK and SMILE demonstrate the procedural breadth to select the most appropriate option for each individual patient.
Implantable Collamer Lens (ICL)
ICL is not a laser procedure at all — it is an intraocular lens implantation. A thin, foldable lens made of collagen-polymer material is inserted through a small incision and positioned in the space between the iris and the natural crystalline lens. ICL corrects myopia from approximately minus 3.00 to minus 20.00 diopters and myopic astigmatism.
ICL is appropriate for patients whose prescriptions are too high for safe laser correction, whose corneas are too thin for adequate ablation depth, or who cannot tolerate contact lens wear and are not laser candidates for other reasons. Unlike laser procedures, ICL does not remove corneal tissue, making it theoretically reversible — though it is intended as a permanent implant.
ICL results in large published series are excellent, with outcomes comparable to or exceeding those of LASIK for appropriate candidates. Practices that offer ICL alongside their laser procedure options are providing a more complete refractive surgery service and demonstrating the diagnostic sophistication to match patients to their optimal procedure.
Frequently Asked Questions
Q: What is the difference between LASIK and bladeless LASIK? Traditional LASIK uses a mechanical blade (microkeratome) to create the corneal flap; bladeless LASIK uses a femtosecond laser. The excimer laser treatment of the corneal tissue is similar in both cases. Bladeless LASIK is currently the standard at leading practices due to improved flap precision and customizability. See Patient Safety Standards in Award-Winning LASIK Practices for more on how flap creation method affects safety.
Q: Is wavefront-guided LASIK worth the additional cost? For patients with measurable higher-order aberrations — particularly those in professions requiring excellent night vision — wavefront-guided treatments have demonstrated superior outcomes in quality-of-vision measures. The additional cost is justified by the evidence in these patient populations.
Q: How do I know which type of LASIK is right for me? Your corneal topography, wavefront measurements, prescription range, and lifestyle factors all inform which procedure and treatment profile is most appropriate. This determination should be made during a thorough consultation with an experienced refractive surgeon. See LASIK Consultation: What to Expect and What to Ask for preparation guidance.
Q: Is SMILE better than LASIK for everyone? SMILE has specific advantages — particularly for dry eye risk and biomechanical preservation — but does not yet offer the same degree of higher-order aberration correction integration available with wavefront-guided LASIK, and cannot treat hyperopia. For most patients, the outcomes of current-generation SMILE and wavefront-guided LASIK are comparable. The optimal choice depends on individual anatomy and priorities.
Next Steps
Understanding the distinctions between procedure types gives you a more informed foundation for your consultation and helps ensure that the procedure recommended for your eyes is actually the most appropriate option for your anatomy and lifestyle.
The LASIK Surgery Awards program recognizes practices that offer procedural breadth and match patients to appropriate procedures based on clinical evidence. Visit the program directory to find evaluated providers in your area.
*Procedure descriptions on this page reflect current clinical availability and FDA approval status as of publication date. Technology availability varies by practice.*