How LASIK Surgery Works
LASIK surgery is performed in several stages, using advanced laser technology to reshape the cornea. Here’s a breakdown of the entire process:
1. Preoperative Assessment
Before undergoing LASIK surgery, a thorough evaluation is essential to determine if you’re a suitable candidate. This typically includes:
- Comprehensive Eye Examination: The ophthalmologist will assess the health of your eyes, measure the refractive error (how much nearsightedness, farsightedness, or astigmatism you have), and check your corneal thickness.
- Corneal Mapping: This helps to map the surface of your cornea to ensure it has the correct curvature and to identify any irregularities.
- Pupil Dilation: The pupils may be dilated to assess the health of the retina and optic nerve.
- Review of Medical History: Your doctor will check for any contraindications, such as dry eye, active eye disease, or an unstable refractive prescription.
2. The LASIK Procedure
The LASIK procedure itself is relatively quick, often taking around 15 to 30 minutes for both eyes, and it is typically done on an outpatient basis. Here’s how the surgery is performed:
Anesthesia: LASIK is performed under local anesthesia, typically in the form of numbing eye drops. You will be awake during the surgery but should not feel any pain. Some patients may also receive mild sedation to help them relax.
Flap Creation:
- The first step in LASIK is to create a thin, hinged flap in the cornea. This is done using either a microkeratome (a precise surgical instrument with a blade) or more commonly today, a femtosecond laser.
- The flap is carefully lifted to expose the underlying corneal tissue (the stroma). This flap is essential because it allows the surgeon to reshape the cornea without affecting its surface layer.
Reshaping the Cornea:
- The surgeon uses an excimer laser to reshape the corneal stroma. The excimer laser is a cool ultraviolet light that can precisely remove microscopic amounts of tissue from the cornea.
- For nearsightedness (myopia), the surgeon flattens the central part of the cornea, reducing its focusing power.
- For farsightedness (hyperopia), the surgeon steepens the cornea to increase its focusing power.
- For astigmatism, the surgeon reshapes the cornea to create a more symmetrical shape, correcting the uneven curvature.
Flap Replacement:
- Once the reshaping is complete, the flap is carefully repositioned over the cornea, where it naturally adheres without the need for stitches. The cornea starts healing almost immediately, and the flap stays in place.
3. Postoperative Care
After the surgery, patients typically experience immediate vision improvement, though some blurriness, dryness, or mild discomfort is common for the first few days. Here’s what to expect in the recovery process:
Eye Drops: To promote healing and prevent infection, the surgeon will prescribe antibiotic and anti-inflammatory eye drops. Artificial tears may also be recommended to manage dryness.
Rest: Most patients are encouraged to rest for a few hours after surgery. You can resume normal daily activities like reading, watching TV, or using the computer, but you should avoid strenuous exercise or activities that may expose the eyes to dirt or dust.
Follow-Up Visits: You’ll have follow-up appointments scheduled at one day, one week, and one month post-surgery. These visits help ensure that the eyes are healing well, the flap is properly in place, and the vision is improving as expected.
Recovery Time: Most patients experience significant vision improvement within 24 to 48 hours, with the majority reaching their final vision outcome in several weeks to a few months. The healing time varies depending on the individual, but vision stabilization typically takes a few months.
4. Long-Term Care
Although LASIK offers long-lasting results, some patients may experience changes in vision over time due to natural age-related conditions (such as presbyopia or cataracts). However, LASIK does not prevent the natural aging of the eyes, and it’s important to have regular eye exams to monitor eye health.
