When Is It Appropriate to Undergo Myopia Surgery?

Reader Question:

“I’m 28 years old with nearly –6 diopters of myopia and 1 diopter of astigmatism. Which surgical methods are suitable, and what should I prepare?”
— Anh Thi, Lâm Đồng

Answer:

Myopia surgery corrects nearsightedness by reshaping the curvature of the cornea, enabling clear vision without glasses.

1. Age and Stability Requirements

• Ideal candidates are at least 18 years old.

• Your prescription must be stable, changing by no more than ±0.5 diopter within the past year.

2. Corneal Thickness and Health

• Higher myopia requires more corneal tissue removal.

• The cornea must be at least 450 micrometers thick to ensure surgical safety.

• You must be free from acute or chronic eye diseases—such as keratitis, corneal dystrophy, keratoconus, or retinal hemorrhage.

• Pregnant or breastfeeding women should wait at least 6 months after childbirth to allow stable hormone levels and refractive error.

3. Surgery Methods

✔️ Corneal Procedures

• SMILE Pro (Small Incision Lenticule Extraction Pro):

  • The most advanced, creating no flap, which avoids associated risks like flap dislocation or wrinkles.

  • Laser time is only 10 seconds per eye, with a small incision and minimal scarring.

  • Offers reduced dry eye and a more comfortable recovery.

✔️ Other Corneal Lasers – FLEx, LASIK, Trans-PRK

• These involve flap creation or stromal reshaping.

• Useful for patients with less severe myopia but involve more postoperative discomfort and transient dryness.

✔️ Phakic ICL (Implantable Collamer Lens) – Intraocular Method

• Instead of reshaping the cornea, a thin, customized lens is inserted behind the iris, in front of the natural lens—through a 2–3 mm incision.

• Safe for high myopia or thin corneas, preserving corneal strength and avoiding dry eye issues.

• The lens is long-lasting and can be replaced or adjusted over time.

4. Diagnosis & Preoperative Testing

To qualify, you’ll undergo:

• Refractive measurement (sphere and cylinder).

• Corneal topography (e.g., Pentacam), assessing thickness and structure.

• Biomechanical evaluation (e.g., Corvis ST) to test corneal strength.

• Retinal exam (Optos) to check for thinning or degeneration—especially with high myopia.

• Blood tests, ultrasound, and anesthesia evaluation.

After clearance, the process from pre-op to discharge can be completed within an hour at top eye centers.

5. What to Expect After Surgery

• Temporary discomfort like watering or grittiness is common just after the procedure.

• You’ll need a protective eye shield for 24 hours, even during sleep.

• By 24 hours post-op, most patients can drive or fly—but avoid dusty places and strong light for the following weeks.

• Vision generally stabilizes rapidly, often within a day with SMILE Pro.

✔️ Summary of Candidacy and Procedures

🏥 Best Candidates & Methods

• SMILE Pro is favored for its fast laser time (~10 seconds) and quick recovery.

• Phakic ICL is best for severe myopia or thin corneas, preserving corneal integrity.

• Other laser methods (LASIK, Trans-PRK) remain applicable for certain prescriptions.

Expert**

Dr. Đinh Trung Nghĩa, Deputy Director, High-Tech Eye Center, Tam Anh General Hospital, Ho Chi Minh City.