What are the Risks to Lasik Eye Surgery?

Lasik eye surgery is a surgical procedure which corrects deteriorating vision by reshaping the surface of the eye, more precisely the corneal layer in such a manner that light enters the eye at the angle appropriate for correct vision. Nearsightedness (myopia), farsightedness (hyperopia) and astigmatism or blurry vision can be superficially corrected using spectacles or contact lenses, but Lasik surgery digs deeper and removes the underlying refraction errors permanently thereby dispensing the need to use any eye-wear. Even if the benefits of Lasik surgery are tangible and long lasting, patients considering the surgical route need to weigh the risks associated with Lasik surgery.

The eternal dilemma: whether to retain eye-wear or opt for risky eye surgery

Surgery is an invasive procedure and when a sensitive organ such as the human eye is under the surgeon’s scalpel, even the slightest surgical error can spell disaster for the eye and the precious gift of vision. If you are considering Lasik surgery, it becomes important to weigh the risks against the perceived rewards and determine whether the surgery is justified in your case. The ophthalmologist will be more conscious of this dilemma and will do his best to discuss your fears, allay your doubts and educate you clearly regarding the options that are at your disposal. If your overall health is not up to the mark, you may be better off considering glasses and contact lenses as external aids to rectify refraction errors without messing with the eye. 

The major risks involved in a Lasik surgery

1.     Imperfect removal of corneal tissue

The mid-section stroma is the thickest layer of the cornea which is reshaped by the excimer laser. This layer is studied and mapped by computerized imaging prior to the Lasik surgery. Only the right amount of tissue at specified locations are removed using the excimer laser and rapid advancements in technology have reduced the margin of error substantially. But mistakes do occur.

When under correction, too little stroma may be removed and this would interfere with proper vision particularly in people affected by shortsightedness – inability to view distant objects clearly.  Only a repeat surgery can correct the error. In over-correction, more stroma is removed than what was originally planned. The only way to fix this error is through glasses and contact lenses with suitably adjusted refractive errors. This means you get saddled with eye-wear even after surgery, nullifying the original intention of the Lasik surgery.

2.     Refractive errors that resurface after presbyopia

Even after successful restoration of disoriented vision after Lasik surgery, people approaching their 50s tend to develop a weakening in the elasticity of their lens – an eye condition called presbyopia. Such people have no option but to opt for new eye-wear which is needed to correct nearsightedness and farsightedness. What this implies is that the eye-wear cannot be totally dispensed through Lasik surgery. One alternative is the monovision treatment in which one eye is corrected for nearsightedness and another is corrected for farsightedness. But people may struggle to get used to the vision challenges, especially when driving at night.

3.     Disturbed vision after Lasik surgery

Lasik surgery may present a new set of challenges in few patients. These include driving in low light at dusk or dawn resulting in halos around bright objects, exceptional glare and shadows that trail objects and create double-vision. The doctor may prescribe new eye-wear to correct vision distortion or reschedule failed surgery two to three months following Lasik surgery. Repeat surgery following Lasik (and increased cost of treatment) cannot be ruled out.

4.     Dysfunctional tear sacs and eye dryness

Lasik surgery often causes the tear glands to slow down its tear production resulting in dry eyes and attendant discomfort. This is more pronounced in the initial months following Lasik surgery. To combat the discomfort, doctors recommend constant use of eye drops to moisturize the eyes. If the discomfort is severe, special plugs may be inserted into the tear duct to prevent excessive drainage of tears and redirect moisture to the eye surface.

5.     Imperfect healing of the epithelial corneal flap

In Lasik surgery, the thin outer epithelial layer of the cornea is sliced and shifted to one side as a flap which is re-positioned after laser bombardment of the stroma. In rare instances the flap does not heal properly, leading to infection and inflammation of the cornea and vision blurriness. This condition usually calls for prolonged treatment using anti-inflammatories and antibiotics under close medical supervision.

6.     Development of corneal ectasia

The cornea is the three-layered dome shaped structure on the outer surface of the eye which is surgically manipulated in Lasik surgery using an excimer laser. In rare cases, the surgical reshaping of the corneal tissue may not produce the desired results. Instead of a dome shape, the patient could be saddled with a distantly conical cornea – a condition called corneal ectasia which occurs due to changes in the surface pressure and which progressively distorts vision. This can be corrected using specialized contact lenses or through a repeat laser surgery.   

Risk factors proportionately increase in Lasik candidates with pre-existing conditions

• Autoimmune disorders like diabetes, rheumatoid arthritis, scleroderma and immune deficiency diseases like HIV interfere with the healing of the eye. Such candidates are at a high risk of developing complications if they opt for Lasik surgery. Also, corrective medicines create vision disturbances. 
• Pregnant and lactating (breastfeeding) moms undergo frequent hormonal changes that prevent speedy eye healing. Such candidates are usually discouraged from undergoing Lasik surgery.

People who should be avoiding Lasik eye surgery considering the risks involved

• Candidates younger than 21 years are at a high risk of developing Lasik complications. In youngsters, the attraction of fast and simple cosmetic eye improvement may be too strong to resist. But Lasik cannot be treated as a routine procedure at younger ages because the eyes are still considered to be in their growing stages, and growth needs to be stabilized before risking surgery.
• People with thinner corneas and larger pupils are at a risk of developing Lasik complications. For Lasik to be successful, the cornea has to be of sufficient thickness to enable adequate laser guided tissue removal. A larger pupil admits more light than the required amount and is best corrected using suitable eye-wear.  
• People who pursue active careers in sports, engineering and designing professions which demand high visual acuity or those who are involved in acting and fashion modeling need to weigh the risks alongside the rewards of Lasik surgery. There is always the danger that the risks associated with Lasik surgery may compromise their ability to work efficiently and pursue their vocations without downtime.  

The last word

Lasik surgery is undoubtedly successful as a procedure that seeks to permanently cure the underlying refractive errors that cause nearsightedness, farsightedness and astigmatism. But if your overall vision is considered healthy by doctors and refractive errors are within a manageable spectrum, eye-wear is still the cheapest and the most easily accessible solution. Ultimately, vision improvement through Lasik surgery may remain cosmetic till presbyopia sets in during the 50s and requires correctional eye-wear. The moot question is, would you risk your eyes and vision through a surgical procedure with an uncertain outcome when there are cheaper and safer alternatives available?