The phrase “minimally invasive” can make laser vision correction sound almost effortless. In reality, every refractive procedure changes corneal tissue, produces a healing response, and carries possible side effects. The key difference is how the surgeon reaches the tissue being reshaped.

For readers looking forward to SMILE eye surgery: a femtosecond laser forms a small, disc-shaped layer of tissue called a lenticule inside the cornea. The surgeon removes it through a small opening, changing the corneal shape without creating a LASIK-style flap [1].

That approach may appeal to patients interested in a small corneal access opening and a relatively quick return to routine. It does not make SMILE suitable for every prescription or every eye. LASIK and PRK may be preferable in other situations.

How minimally invasive procedures are defined in eye surgery

“Minimally invasive” is a relative description rather than a guarantee of an easier outcome. In corneal refractive surgery, it may refer to the amount of surface tissue disturbed, the size of the access opening, whether a flap is created, and how much tissue must heal before vision becomes functional.

SMILE uses a small corneal opening to provide access to a lenticule created beneath the surface. LASIK preserves most of the surface epithelium but requires a hinged flap. PRK avoids a flap, yet the surface epithelium must regrow after treatment.

Each procedure changes a different part of the cornea and follows a different healing pathway. The smallest opening is not automatically the safest or most suitable choice. The recommendation depends on the prescription, findings from the eye examination, previous surgery, daily activities, and the patient’s recovery priorities.

For myopia, a network meta-analysis of 48 randomized trials found no statistically significant pairwise differences in uncorrected visual acuity, safety, higher-order aberrations, or contrast sensitivity among the procedures studied. Predictability differed in some comparisons, supporting individualized selection rather than a universal ranking [4].

What happens during SMILE, LASIK, and PRK

Preparation varies by procedure and laser platform. The cited SMILE information describes topical anesthetic drops, while FDA LASIK guidance describes numbing drops, a lid speculum, fixation instructions, pressure, and temporary visual changes [1,2]. Patients considering PRK should ask their surgeon what positioning and sensations to expect.

During SMILE, a femtosecond laser creates the lenticule and a small access opening while the eye is positioned beneath a curved contact surface. The surgeon separates and removes the lenticule through that opening. Removing the tissue changes the cornea’s curvature and focusing power [1].

The laser portion is brief, but manual separation and removal of the lenticule remain important parts of the operation. SMILE is flapless, yet it is still surgery within the corneal stroma.

LASIK uses a femtosecond laser or, less commonly, a mechanical instrument to create a corneal flap. The surgeon lifts the flap, uses an excimer laser to remove a programmed amount of stromal tissue, and returns the flap to position without stitches [2].

This flap provides rapid access to the treatment area and often supports quick early visual recovery. It also creates flap-specific considerations, including the need to avoid rubbing the eyes and to follow early activity restrictions.

PRK takes a surface-based approach. The surgeon removes the epithelium, the cornea’s outer cellular layer, before an excimer laser reshapes the exposed stromal tissue [3]. A bandage contact lens is then commonly used to protect the surface and reduce discomfort while the epithelium regenerates [5].

These differences shape the first week of healing. A LASIK flap must settle, the SMILE access opening and internal interface must recover, and the PRK epithelium must regrow.

How discomfort and vision may change during the first week

Immediately after corneal laser surgery, vision may be cloudy or unstable. Burning, watering, light sensitivity, a gritty sensation, glare, halos, and difficulty focusing can occur. Patients should arrange transportation home and should not drive until their surgeon confirms that their vision meets the necessary standard.

After LASIK, irritation is often most noticeable during the first several hours. Vision may improve substantially by the next day, although haziness, dryness, glare, and fluctuation can continue. FDA guidance notes that early symptoms commonly improve during the first few days, while complete visual stabilization may take longer [2].

SMILE can also produce blurred or fluctuating vision during the early postoperative period. Some patients resume ordinary activities quickly, but early visual quality does not always recover faster than after LASIK.

In one prospective comparison, standard visual-acuity outcomes were similar after SMILE and LASIK, but contrast sensitivity was better in the LASIK group on the first day and at one week. Patient-reported quality of vision was also worse in the SMILE group at seven days, although the difference was no longer significant at one month [6].

A small access opening therefore does not guarantee immediately sharper vision. Early recovery can also be influenced by the prescription treated, postoperative dryness, inflammation, laser settings, and individual healing.

Because PRK removes the epithelium, early postoperative pain can be significant. A bandage contact lens is used to reduce discomfort while the treated area re-epithelializes [5]. Recovery instructions and the timing of bandage-lens removal should come from the treating surgeon.

Dryness also deserves attention. A meta-analysis found significant average reductions in tear-film breakup time and tear production after LASIK. Pooled changes after SMILE and PRK did not reach statistical significance, although the limited number and quality of available studies reduced certainty about the comparison [7].

Research on corneal nerves has found less early nerve disruption after SMILE than after femtosecond LASIK, with the differences narrowing over time [8]. This may help explain different patterns of dryness or sensitivity, but it does not mean SMILE prevents dry eye.

During the first week, patients should follow their surgeon’s instructions about eye drops, shields, bathing, screen use, makeup, exercise, work, and driving. The FDA advises LASIK patients to contact their eye doctor immediately for severe pain or symptoms that worsen rather than improve [2]. Patients undergoing SMILE or PRK should follow the urgent-contact instructions provided by their own surgical team.

Questions to ask before deciding on a procedure

A consultation should do more than identify the procedure with the shortest advertised recovery. It should explain why one approach fits the patient’s eyes, prescription, health, and priorities better than the alternatives.

Useful questions include:

• Which procedures can treat my prescription, and is it stable enough for surgery?
• Do my corneal thickness and scans make any option unsuitable?
• Is my tear film healthy enough for surgery?
• How could dry eye or contact lens intolerance affect recovery?
• What should I expect during the first day and first week?
• When can I safely drive, work, exercise, swim, or wear eye makeup?
• Which complications are specific to the recommended procedure?
• How often are enhancements or additional treatment needed?
• Who will manage postoperative visits and urgent concerns?
• How could presbyopia or future cataracts affect my long-term vision?

Patients should also ask which laser platform will be used, whether it is approved for the intended treatment, and how much experience the surgeon has with that device and procedure. FDA guidance advises patients not to choose refractive surgery on price alone and warns that no medical procedure can guarantee a particular visual result [9].

The recovery discussion should be specific. “Back to normal tomorrow” may mean that a patient can use a computer or return to desk work, not that the cornea has fully healed or that night vision has stabilized.

As a patient-education resource, smileandsee.com can help readers understand how small-incision lenticule extraction differs from flap-based and surface-based procedures. The final choice still requires a comprehensive examination and a balanced discussion of risks, alternatives, recovery, and long-term expectations.

Minimally invasive laser vision correction can offer a relatively short interruption to daily life for carefully selected patients. The most appropriate procedure, however, is not simply the one with the smallest opening or the fastest promotional recovery claim. It is the one that fits the anatomy of the eye and provides an acceptable balance of visual goals, healing demands, and clinical risk.

References

[1] Carl Zeiss Meditec. (n.d.). What to expect with ZEISS SMILE. Retrieved July 16, 2026.

[2] U.S. Food and Drug Administration. (2018, July 11). What should I expect before, during, and after surgery?

[3] U.S. Food and Drug Administration. (2021, January 15). What is LASIK?

[4] Wen, D., McAlinden, C., Flitcroft, I., Tu, R., Wang, Q., Alió, J., Marshall, J., Huang, Y., Song, B., Hu, L., Zhao, Y., Zhu, S., Gao, R., Bao, F., Yu, A., Yu, Y., Lian, H., & Huang, J. (2017). Postoperative efficacy, predictability, safety, and visual quality of laser corneal refractive surgery: A network meta-analysis. American Journal of Ophthalmology, 178, 65–78. https://doi.org/10.1016/j.ajo.2017.03.013

[5] Sánchez-González, J.-M., López-Izquierdo, I., Gargallo-Martínez, B., De-Hita-Cantalejo, C., & Bautista-Llamas, M.-J. (2019). Bandage contact lens use after photorefractive keratectomy. Journal of Cataract & Refractive Surgery, 45(8), 1183–1190. https://doi.org/10.1016/j.jcrs.2019.02.045

[6] Chiche, A., Trinh, L., Saada, O., Faure, J.-F., Auclin, F., Baudouin, C., & Denoyer, A. (2018). Early recovery of quality of vision and optical performance after refractive surgery: Small-incision lenticule extraction versus laser in situ keratomileusis. Journal of Cataract & Refractive Surgery, 44(9), 1073–1079. https://doi.org/10.1016/j.jcrs.2018.06.044

[7] Sambhi, R. D. S., Sambhi, G. D. S., Mather, R., & Malvankar-Mehta, M. S. (2020). Dry eye after refractive surgery: A meta-analysis. Canadian Journal of Ophthalmology, 55(2), 99–106. https://doi.org/10.1016/j.jcjo.2019.07.005

[8] Jiang, X., Wang, Y., Yuan, H., Li, Y., Wang, H., An, Z., & Li, X. (2022). Influences of SMILE and FS-LASIK on corneal sub-basal nerves: A systematic review and network meta-analysis. Journal of Refractive Surgery, 38(4), 277–284. https://doi.org/10.3928/1081597X-20220127-01

[9] U.S. Food and Drug Administration. (2018, August 8). What are the risks and how can I find the right doctor for me?

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