Differentiating Refractive Surgery Methods
The advancement of medical technology offers those with myopia numerous options to “say goodbye to glasses,” yet many are confused by a plethora of names such as Femto LASIK, SmartSight, ReLEx SMILE, or Phakic ICL. So, how do these methods differ, and who is suitable for each technique?
Refractive eye surgery is a surgical intervention aimed at correcting refractive errors like myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia.
During the online seminar “Choosing Safe Myopia Surgery Methods” organized by Dan tri newspaper, experts provided in-depth analysis and consultation on this matter.
According to Assoc. Prof. Dr. Nguyen Duc Anh, former Head of the Refractive Department (National Eye Hospital), refractive error correction surgeries are currently divided into two main groups.
Group 1: Surgery with corneal flap creation (LASIK, Femto LASIK, or SmartFemto)
The doctor creates a thin flap on the cornea using a mechanical blade or a femtosecond laser, then uses an excimer laser to correct the refractive error, and finally repositions the corneal flap.
“The advantage of this method is quick operation, with significant vision improvement within a few days, but patients need to avoid rubbing their eyes or participating in activities prone to impact for about one month initially,” said Assoc. Prof. Duc Anh.
Group 2: Flapless corneal surgery (ReLEx SMILE, SmartSight, CLEAR, SILK…).
Instead of creating a flap, the doctor makes a small incision of a few millimeters to separate and remove a thin layer of tissue inside the cornea to correct the refractive error.
Flapless methods help reduce dry eyes, are less invasive, and allow patients to return to normal activities sooner. However, the cost is often higher and requires modern equipment and experienced doctors.
Assoc. Prof. Duc Anh emphasized: “The names may vary depending on the machine manufacturer, but essentially, they are all based on the same principle of modern refractive surgery, differing only in how the corneal tissue is created and removed.”
Hong Ngoc General Hospital is one of the few facilities in the country capable of simultaneously performing three new-generation refractive surgery technologies: SmartFemto, SmartSight, and Phakic ICL.
This allows doctors to choose the optimal option based on each individual’s eye characteristics.
SmartFemto is often applied as a safe choice for individuals with thick corneas and not excessively high myopia and astigmatism.
According to Dr. Dinh Thi Hoang Anh, Head of Ophthalmology (Hong Ngoc General Hospital), “many people can return to work three days after SmartFemto surgery, with eyes fully stable after about two to three weeks, depending on individual constitution.”
Meanwhile, SmartSight uses a new generation femtosecond laser with extremely high precision, allowing for quick operations, reduced dry eyes, and suitability for people with active lifestyles. “Because no flap is created, patients can return to sports activities, especially contact or ball sports, sooner than with SmartFemto,” Dr. Hoang Anh shared.
SmartSight is considered a more modern version of ReLEx SMILE, inheriting the principle of surgery through a small incision but with improvements in speed and laser energy control.
In addition to the two laser-based surgery groups, Phakic ICL (implantable collamer lens surgery) is an option for individuals with high myopia or thin corneas who are not suitable for laser surgery.
According to Dr. Hoang Anh, Phakic ICL is particularly suitable for those with myopia ranging from -8 to -18 diopters, or corneas too thin for laser surgery.
The biggest difference with Phakic ICL is that it does not alter the cornea, thus fully preserving the natural structure of the eye.
“The lens is placed in the anterior chamber, acting like a ‘miniature contact lens’ inside the eye, correcting refractive errors without ablating the cornea.
However, patients must undergo thorough examination to assess the anterior chamber depth and endothelial cell count before indication,” Dr. Hoang Anh shared.
Thus, despite different names, all refractive surgery techniques aim for a common goal: helping patients see clearly without glasses, with varying degrees of intervention and recovery times. The choice of suitable method should be based on eye characteristics and the specialist doctor’s recommendation, rather than subjective feelings or advertisements for the “latest” technology.
Do Eyes Weaken or Myopia Return After Surgery?
Although refractive surgery is increasingly popular, many people still wonder: “Is surgery safe?”, “Will myopia return?”, “How long until vision is clear?”, or “Are there any special restrictions?”. These questions were also specifically answered by experts during the seminar.
Is refractive surgery safe?
According to Assoc. Prof. Dr. Nguyen Duc Anh, current refractive surgery technologies such as SmartFemto and SmartSight achieve high precision and are approved by the U.S. Food and Drug Administration (FDA).
“If previously the biggest risks of complications were corneal flap displacement or prolonged dry eyes, with new generation laser technology, these risks have significantly reduced,” he affirmed.
At facilities with adequate equipment and strict sterile procedures like Hong Ngoc General Hospital, all surgeries are performed in positive-pressure operating rooms, minimizing bacterial contamination. Each surgery lasts only 10-15 minutes, and patients can go home the same day.
“Refractive surgery is currently considered one of the safest interventions in ophthalmology, provided that patients are thoroughly screened and adhere to post-operative care,” Assoc. Prof. Duc Anh emphasized.
Is dry eyes or blurred vision after surgery a concern?
According to Dr. Dinh Thi Hoang Anh, the sensation of dry or slightly gritty eyes is a normal post-operative reaction due to temporary cutting of corneal nerve endings during laser application.
“This sensation will rapidly decrease within a few days and almost completely disappear after two to three weeks. At Hong Ngoc, we always instruct patients to apply artificial tears correctly and maintain adequate blinking habits to prevent prolonged dryness,” Dr. Hoang Anh shared.
Assoc. Prof. Duc Anh also added that slight blurriness in the first few days is due to the eyes adapting: “Vision typically reaches 8-9/10 immediately after surgery and fully stabilizes after about two weeks, depending on individual constitution and the chosen method.”
Will myopia return after surgery?
This is the most common question. According to Assoc. Prof. Duc Anh, refractive surgery does not change genetic predispositions, so the possibility of myopia returning can still occur if patients work with screens for extended periods, lack sleep, or overuse their eyes.
“Recurrence of myopia is not due to surgical failure, but because the eyes continue to be under pressure after surgery. This is similar to recovering from an illness but relapsing due to not maintaining proper care,” he explained.
Hong Ngoc Hospital currently applies a schedule of 5 follow-up appointments (1 day, 1 week, 1 month, 3 months, and 6 months) to monitor vision and remind patients to adjust their habits regarding screen time, lighting, and sleep.
When can normal activities and work resume?
According to Dr. Hoang Anh, patients who undergo SmartFemto typically can return to work after 3-5 days, while SmartSight allows for faster recovery due to not creating a corneal flap.
“We advise patients to wear protective glasses when outdoors, avoid smoke and dust, refrain from eye makeup for the first two weeks, and get enough sleep for optimal eye recovery,” this expert instructed.
Assoc. Prof. Duc Anh also noted that the most crucial factor is not the surgical technology but post-operative care.
“If patients adhere to follow-up appointments and care instructions, the complication rate is almost zero. Surgery accounts for only 10% of success; the remaining 90% depends on patient cooperation,” he emphasized.
Does refractive surgery affect long-term health?
According to experts, refractive surgery only affects the corneal layer and does not impact deeper structures such as the lens or retina. However, a comprehensive eye examination before surgery is mandatory to rule out potential underlying conditions like retinal degeneration or glaucoma.
At Hong Ngoc General Hospital, the pre-operative examination process takes about 2 hours with over 10 measurement steps: corneal mapping, thickness, dry eye assessment, fundus examination, contrast sensitivity, objective and subjective refraction… helping doctors accurately determine the condition of each eye before making an indication.
Thanks to this strict screening process, the rates of myopia recurrence or prolonged dry eyes after surgery at centers applying SmartFemto and SmartSight technologies are recorded at less than 1%.
Important Notes Before and After Myopia Surgery for Best Results
According to Assoc. Prof. Dr. Nguyen Duc Anh, patients should only undergo surgery if they meet three criteria: stable vision, sufficient corneal thickness, and no underlying fundus diseases. “Do not undergo surgery due to trends or advertisements for the latest technology. Healthy eyes are more important than getting rid of glasses a few months early,” he advised.
Dr. Dinh Thi Hoang Anh also emphasized the importance of adhering to follow-up appointments and post-operative care.
According to Dr. Hoang Anh, after surgery, patients should maintain good habits such as:
- Wearing protective glasses when outside to avoid smoke and dust.
- Sleeping 7-8 hours daily for eye cell regeneration.
- Avoiding prolonged use of phones and computers in the initial stages.
- Regularly applying artificial tears, specifically the type prescribed by the doctor.
- Not rubbing eyes, even if there’s a slight gritty sensation.
“Maintaining healthy eyes is not just about a few weeks after surgery but a long-term journey. Treat eye care as a lifestyle habit, not a temporary task,” Dr. Hoang Anh shared.
Both experts believe that patients need to remain level-headed before making a decision. Thorough examination and consultation at a reputable facility with complete diagnostic equipment, such as corneal mapping, dry eye measurement, and fundus examination, will help accurately determine the appropriate method.
“Refractive surgery is a modern option, but it is truly meaningful only when patients understand their eyes well and know how to care for them after surgery,” Assoc. Prof. Duc Anh concluded.
Photos: Thanh Dong
Source link: https://dantri.com.vn/suc-khoe/nhung-diep-quan-trong-can-biet-truoc-khi-quyet-dinh-mo-can-20251104144346277.htm
