LASIK and Laser Vision Correction Technologies: An Evidence-Based Guide

“LASIK” is often used as a blanket term, but laser vision correction today spans several distinct technologies — each with its own method, evidence base, and ideal candidate. This guide explains every major option factually, with reference to published clinical studies, so you can understand what genuinely separates them. It is written for information only; the right procedure for any individual can be determined only by a qualified ophthalmologist after a full eye evaluation.

Across the literature, modern laser vision correction is consistently safe and effective: a widely cited review of global LASIK outcomes (Solomon et al., Ophthalmology, 2009) reported patient satisfaction of around 95%. The technologies below represent the evolution of that field.

The Four Families of Refractive Surgery

Before the individual technologies, it helps to know the categories:

1. Flap-based laser (LASIK): a thin corneal flap is created, the laser reshapes the tissue beneath, and the flap is replaced.
2. Surface laser (PRK, LASEK, TransPRK): no flap; the cornea is reshaped at the surface.
3. Lenticule extraction (SMILE, SMILE Pro, SILK): a small disc of tissue is removed through a tiny incision, without a full flap.
4. Lens-based (ICL, IPCL): no corneal tissue is removed; a lens is implanted inside the eye.

1. Standard (Conventional) LASIK

What it is: The original LASIK technique, in which the corneal flap is created with a mechanical blade (microkeratome) before an excimer laser reshapes the cornea.

Evidence & status: Standard LASIK has decades of data behind it and remains effective, but in most modern practices the mechanical flap has been replaced by a laser-created flap (see Femto LASIK), which studies associate with more consistent flap thickness and fewer flap-related complications.

Best suited to: Largely of historical importance today; most centres now default to bladeless flap creation.

2. Femtosecond (Bladeless) LASIK

What it is: LASIK in which the flap is created by a femtosecond laser rather than a blade — hence “bladeless.” The excimer laser then performs the corneal reshaping.

How it works: Two lasers are used — a femtosecond laser for the flap and an excimer laser for the ablation. Recovery is fast, with most patients seeing well within 24–48 hours.

Evidence: Femtosecond flap creation is associated with greater precision and predictability of flap dimensions compared with mechanical microkeratomes, and it is the contemporary standard for flap-based LASIK.

Best suited to: Most standard candidates with adequate corneal thickness and a stable prescription.

3. Wavefront-Optimized and Wavefront-Guided (Customized) LASIK

What it is: “Customized” LASIK that goes beyond your glasses prescription to address the eye’s finer optical imperfections (higher-order aberrations, or HOAs).

• Wavefront-optimized: uses an aspheric profile to preserve corneal shape and limit new aberrations.
• Wavefront-guided: uses a detailed map of the eye’s existing aberrations to target them specifically.

Evidence: Wavefront-guided treatments are well documented to reduce higher-order aberrations and improve quality-of-vision measures in suitable eyes, particularly those with significant pre-existing HOAs.

A note on brand names: Customized LASIK is marketed by various clinics under proprietary names — for example, “Custom Eyes.” These are brand names for customized/wavefront-guided treatment, not separate technologies. (See the section on Foresight below for the related planning software.)

Best suited to: Patients wanting the best achievable quality of vision, especially for night driving and detailed work.

4. Topography-Guided LASIK (Contoura Vision)

What it is: A customized LASIK that bases treatment on a highly detailed map of the corneal surface — Contoura Vision (Alcon) measures roughly 22,000 points across the cornea.

Evidence: In the US FDA pivotal trial (Stulting et al.; T-CAT Study Group, Journal of Cataract & Refractive Surgery, 2016), about 92.6% of treated eyes achieved 20/20 vision or better and around 64.8% achieved 20/16 or better at 12 months, with more than 30% of eyes seeing better unaided after surgery than they had with glasses beforehand. Patients also reported reduced glare and halos.

Best suited to: Eyes with corneal surface irregularities or those seeking premium visual quality. Platform note: runs on the Alcon WaveLight system.

5. Ray-Tracing-Guided LASIK (WaveLight InnovEyes)

What it is: One of the newest personalized LASIK approaches. The InnovEyes Sightmap (Alcon) captures wavefront, tomography, and biometry in a single device and builds an individualized 3D “digital eye model,” from which a ray-tracing algorithm calculates the ablation — performed on the WaveLight EX500.

Evidence: A real-world series of 400 myopic eyes (ray-tracing-guided LASIK, Journal of Cataract & Refractive Surgery, 2023) reported uncorrected distance vision of 20/20 or better in all eyes at three months, 20/16 or better in about 89%, and roughly 96% of eyes within ±0.50 D of the refractive target, with no eyes losing two or more lines. A separate prospective study (Clinical Ophthalmology, 2026) reported 20/20-or-better vision in about 98% of eyes and patient satisfaction near 98%.

Best suited to: Myopia and myopic astigmatism in candidates seeking a fully personalized treatment. Platform note: Alcon WaveLight system.

6. SMILE (Small Incision Lenticule Extraction)

What it is: A flapless procedure. A femtosecond laser (Zeiss VisuMax) forms a lens-shaped disc of tissue (a lenticule) inside the cornea, which is removed through a small 2–4 mm incision. SMILE is approved for myopia (with astigmatism on many platforms).

Evidence: Meta-analyses generally find SMILE and femtosecond LASIK deliver comparable corrected visual acuity, with no significant difference in final clarity (systematic reviews in PLOS One, 2016, and Cornea/PubMed meta-analyses). SMILE tends to show advantages in dry-eye-related measures — for example, better tear-film break-up time and lower (better) Ocular Surface Disease Index scores at six months — likely because the small incision disturbs fewer corneal nerves. Some studies also report modestly lower induced higher-order aberrations with SMILE.

Best suited to: Myopic patients, particularly those prone to dry eye or with active lifestyles. Platform note: requires a Zeiss VisuMax (or equivalent lenticule-capable laser).

7. SMILE Pro

What it is: The next-generation SMILE, performed on the upgraded Zeiss VisuMax 800. It creates the lenticule in roughly 10 seconds and adds features such as automated centration and cyclotorsion (rotational) compensation.

Evidence: As a newer iteration, SMILE Pro shares SMILE’s core evidence base; its specific advantages center on shorter laser time and refined alignment. Long-term comparative data continue to accumulate.

Best suited to: The same candidates as SMILE, where the platform is available.

8. SILK (Smooth Incision Lenticule Keratomileusis)

What it is: A newer flapless lenticule procedure performed on Johnson & Johnson’s ELITA femtosecond laser, using a biconvex lenticule design intended to produce a smooth treatment surface.

Evidence: SILK is among the most recently introduced techniques (US FDA clearance in 2024), so its published evidence base is still early and limited compared with LASIK and SMILE. Initial reports describe good visual recovery, but long-term, large-scale data are not yet mature.

Best suited to: Selected candidates at centres with the platform; appropriate caution applies given the limited long-term data. Platform note: Johnson & Johnson ELITA.

9. PRK and LASEK (Surface Ablation)

What it is: The original laser vision correction approach. No flap is created; the cornea’s surface layer (epithelium) is removed and the excimer laser reshapes the surface directly. LASEK is a variant that preserves and repositions the epithelial layer.

Evidence: PRK has a long track record with visual outcomes comparable to LASIK for suitable prescriptions. The main trade-off is a slower visual recovery — several days to weeks — and more initial discomfort, because the surface must regenerate.

Best suited to: Thin corneas, certain corneal surface conditions, and patients in high-impact roles where a flap is undesirable.

10. TransPRK / “Touchless LASIK” (e.g., SmartSurf / SmartSurfACE)

What it is: An advanced, touch-free surface procedure — transepithelial PRK in which the laser removes the epithelium and reshapes the cornea in a single step, with no blade, no suction, and no instrument contacting the eye. On the SCHWIND Amaris platform this is branded SmartSurf (SmartSurfACE). (Note: although marketed as “touchless LASIK,” it is technically a surface procedure, not flap-based LASIK.)

Evidence: TransPRK shares surface ablation’s structural advantages (no flap, more preserved corneal tissue). Schwind’s SmartPulse Technology is designed to produce a smoother stromal surface, which is associated with faster epithelial healing and good early visual quality relative to older surface techniques.

Best suited to: Thin corneas, dry-eye tendency, and contact-sport or physically demanding lifestyles.

11. EVO ICL (Implantable Collamer Lens)

What it is: A lens-based, non-laser option. A soft, biocompatible lens is implanted inside the eye, in front of the natural lens. It is additive (no corneal tissue is removed) and removable.

Evidence: ICL is well documented for high myopia and reports high patient satisfaction, and it is a primary option where the cornea is too thin or the prescription too high for safe laser reshaping.

Best suited to: Very high prescriptions, thin corneas, or chronic dry eye where laser correction is not advisable.

12. IPCL (Implantable Phakic Contact Lens)

What it is: Another lens-based, non-laser option, and a close relative of the ICL. The IPCL (Implantable Phakic Contact Lens) is a posterior-chamber phakic lens implanted in front of the eye’s natural lens, manufactured by Care Group (India). The main material difference is that the IPCL is made of a hydrophilic acrylic, whereas the ICL uses a collamer material; like modern ICLs, current IPCL versions include a central port to allow natural fluid flow.

Evidence: Comparative studies — including randomized trials and a 2024 systematic review — report that IPCL and ICL deliver comparable visual outcomes, refractive predictability, and safety for moderate-to-high myopia, with or without astigmatism (e.g., Rateb et al., Journal of Ophthalmology, 2022; comparative case series and randomized trials, 2022–2024). The IPCL offers a wider range of sizing and power options and is implanted through a small incision; for presbyopia, a diffractive multifocal IPCL is currently the only multifocal posterior-chamber phakic lens available. It is often more affordable than the ICL, which has made it a widely used option in India and other markets. As with any phakic lens, long-term considerations include the small risks of cataract formation, raised eye pressure, and endothelial cell loss, and longer-term comparative data continue to accumulate.

Best suited to: High prescriptions, thin corneas, or others unsuitable for laser correction who want a lens-based option; corrects myopia, hyperopia, astigmatism (toric versions), and presbyopia (multifocal versions).

13. PresbyMAX / PresbyLASIK (Presbyopia Correction)

What it is: A laser approach for presbyopia (age-related loss of near focus). It reshapes the cornea into a multifocal (bi-aspheric) surface so that one zone serves near vision and another distance. SCHWIND’s module is PresbyMAX, available in monocular, micro-monovision, and hybrid modes.

Evidence: Studies of PresbyMAX (e.g., Luger et al., American Journal of Ophthalmology, 2015; Fu et al., International Journal of Ophthalmology, 2020) report that many patients achieve good binocular distance and near vision and reduced dependence on reading glasses, while noting a neural adaptation period and some quality-of-vision trade-offs.

Best suited to: Presbyopic patients (typically over 40) with a clear natural lens; those with developing cataract are often better served by lens-based options.

Summary Comparison

Technology	Family	Flap?	Notable evidence/feature	Platform
Standard LASIK	Flap laser	Blade	Long history; largely superseded	Various
Femto / Bladeless LASIK	Flap laser	Laser flap	Precise flaps; fast recovery	Various
Wavefront-guided LASIK	Flap laser	Yes	Reduces higher-order aberrations	Various
Contoura Vision	Flap laser	Yes	~93% 20/20+ in FDA trial; 22,000 points	Alcon WaveLight
WaveLight InnovEyes	Flap laser	Yes	Ray-tracing 3D model; ~96% within ±0.5 D	Alcon WaveLight
SMILE	Lenticule	No	Comparable acuity to LASIK; better dry-eye metrics	Zeiss VisuMax
SMILE Pro	Lenticule	No	~10-sec lenticule; refined alignment	Zeiss VisuMax 800
SILK	Lenticule	No	Newest; limited long-term data	J&J ELITA
PRK / LASEK	Surface	No	Long track record; slower recovery	Various
TransPRK / SmartSurf	Surface	No	Touch-free, single-step; tissue-sparing	SCHWIND Amaris
EVO ICL	Lens-based	No	Additive, removable; for high power/thin cornea	STAAR
IPCL	Lens-based	No	Comparable to ICL; wider sizing; often lower cost	Care Group
PresbyMAX	Flap/surface	Varies	Multifocal cornea for presbyopia	SCHWIND Amaris

Newer is not automatically better. Each technology has ideal candidates, and suitability depends on individual corneal and ocular measurements.

What Is SCHWIND Foresight®?

Because it is often mentioned alongside “customized” branding, it is worth clarifying: Foresight is a treatment-planning and simulation software module within the SCHWIND CAM suite for the Amaris laser. It builds a virtual replica (a digital model) of the patient’s cornea, allowing the surgeon to simulate the planned treatment and its expected outcome before surgery. It is a planning tool, not a stand-alone surgical technology.

How the Right Technology Is Chosen

A responsible recommendation depends on objective measurements and lifestyle, not marketing. Key factors include corneal thickness, prescription strength, dry-eye status, corneal regularity, age (for presbyopia), and occupation. The essential first step is a comprehensive evaluation — corneal topography, pachymetry, refraction, and wavefront analysis.

About Netram Eye Foundation

Netram Eye Foundation is a super-speciality eye hospital in Greater Kailash II, South Delhi, with a dedicated refractive team led by Dr. Anchal Gupta. Our laser vision correction is performed on the German-engineered SCHWIND Amaris, supporting Femto LASIK, customized/wavefront-guided treatment, the touch-free SmartSurf (TransPRK), PRK/LASEK, and PresbyMAX. We assess each eye individually and recommend the most appropriate option — including referral pathways when a different approach would serve you better.

Book a refractive evaluation at our Greater Kailash centre.

Frequently Asked Questions

What are the different LASIK technologies? They fall into four families: flap-based LASIK (standard, bladeless/Femto, wavefront-guided, topography-guided Contoura, and ray-tracing InnovEyes); surface ablation (PRK, LASEK, TransPRK/SmartSurf); lenticule extraction (SMILE, SMILE Pro, SILK); and lens-based correction (ICL and IPCL).

Which LASIK technology is the best? No single technology is best for everyone. Studies show modern methods are broadly safe and effective; the right one depends on your corneal thickness, prescription, dry-eye status, and lifestyle, determined by an eye examination.

Is SMILE better than LASIK? Meta-analyses show comparable visual clarity between SMILE and femtosecond LASIK, with SMILE often showing better dry-eye-related measures. LASIK can treat a wider prescription range. The better option is individual.

Is “Custom Eyes” a type of LASIK machine? No. “Custom Eyes” is a clinic marketing brand name for customized/wavefront-guided LASIK, not a distinct machine or technology.

What is touchless LASIK? “Touchless LASIK” usually refers to TransPRK (such as SmartSurf), a surface procedure in which the laser removes the epithelium and reshapes the cornea in one step, with no blade or instrument touching the eye. Technically it is surface ablation rather than flap-based LASIK.

Is newer LASIK technology always better? Not necessarily. Established procedures have larger long-term evidence bases, while the newest ones (such as SILK) have promising but limited long-term data. Suitability for your eyes matters more than novelty.

What is IPCL and how is it different from ICL? IPCL (Implantable Phakic Contact Lens, by Care Group) and ICL (Implantable Collamer Lens, by STAAR) are both lens-based implants placed inside the eye in front of the natural lens. Studies show comparable visual outcomes and safety. The IPCL uses a hydrophilic acrylic material, offers a wider range of sizing and power options, has a multifocal version for presbyopia, and is often more affordable, while the ICL has a longer global track record.

References (verify and hyperlink before publishing)

1. Solomon KD, et al. LASIK world literature review: quality of life and patient satisfaction. Ophthalmology. 2009.
2. Stulting RD, Fant BS; T-CAT Study Group. Results of topography-guided LASIK custom ablation treatment with a refractive excimer laser. J Cataract Refract Surg. 2016;42(1):11–18.
3. Ray-tracing-guided myopic LASIK: real-world clinical outcomes. J Cataract Refract Surg. 2023. (PubMed 37595291)
4. Ray-Tracing-Guided Femtosecond LASIK: Refractive Outcomes, Visual Quality and Patient Satisfaction. Clin Ophthalmol (OPTH). 2026.
5. Dry Eye after SMILE versus Femtosecond LASIK for Myopia: A Meta-Analysis. PLOS One. 2016.
6. Dry Eye after SMILE and Femtosecond LASIK: Meta-Analysis. Cornea. (PubMed 27560032)
7. Luger MHA, et al. Presbyopic LASIK using hybrid bi-aspheric micro-monovision ablation profile. Am J Ophthalmol. 2015.
8. Fu D, et al. Objective optical quality and visual outcomes after the PresbyMAX monocular ablation profile. Int J Ophthalmol. 2020.
9. Arbelaez MC, Arba Mosquera S. The SCHWIND AMARIS Total-Tech Laser as an all-rounder in refractive surgery. Middle East Afr J Ophthalmol. 2009.
10. Rateb M, et al. A Prospective Comparative Study between Implantable Phakic Intraocular Contact Lens (IPCL) and Implantable Collamer Lens (ICL) in Treatment of Myopia in Adults. J Ophthalmol. 2022.
11. Safety and efficacy of implantable phakic contact lens versus implantable collamer lens in myopia correction (randomized clinical trial, IPCL V2 vs ICL V4c). 2024.
12. Implantable phakic contact lens (IPCL): a systematic review. 2024.

Medically reviewed by Dr Anchal Gupta, Senior Eye Surgeon, Netram Eye Foundation. This article is for general information and is not a substitute for a personalised consultation with a qualified ophthalmologist. Clinical figures cited describe published study results for each technology and do not represent outcomes at any specific clinic.