At the LaseRx clinic in Mumbai (Bombay), India, we offer conventional LASIK with a microkeratome, along with blade free LASIK with a femtosecond laser and ReLEx Smile.
Read on to find out more about conventional LASIK with a microkeratome:
In LASIK, the refractive error is corrected by appropriately reshaping the cornea to change its curvature, and hence, it’s focusing power. The Excimer Laser is used to perform this reshaping, by appropriately removing microscopic amounts of tissue. The excimer laser was originally developed to etch microchips. Soon, its ability to precisely sculpt human tissue, particularly corneal tissue, was uncovered. The Excimer laser is a cool laser, which does not heat corneal tissue. It breaks inter-molecular bonds within 0.5 microns of corneal tissue, leading to that tissue getting removed from the cornea. It leaves behind extremely smooth surfaces.
The 193 nm Excimer Laser light, controlled with computer precision, gently pulses to remove a microscopic amount of tissue from specific areas of the cornea. This changes the curvature of the cornea, allowing images to be more sharply focused on the retina.
The beam of light vaporizes microscopic amounts of tissue as it breaks inter bonds. Each pulse of the laser removes .25 microns of tissue or 1/39 millionths of an inch. This allows the cornea to be re-sculpted into a more desirable shape, gently and precisely.
The excimer laser is used for a variety of corneal surgical purposes, of which the most common is corneal reshaping for the correction of refractive errors. It is also successfully used to treat corneal diseases and has helped the partially blind and blind recover their sight. The excimer laser thus has the potential to change the landscape of ophthalmology, especially in terms of refractive corrections.
Utilizing the accuracy and precision of the excimer laser, LASIK changes the shape of the cornea to improve the way light is focused or “refracted” by the eye. By adjusting the pattern of the laser beam through its computer, it is possible to treat high levels of nearsightedness, farsightedness and astigmatism.
LASIK surgery is performed as an outpatient procedure in the comfort and convenience of the excimer laser surgical suite. The entire vision correction procedure takes less than 30 minutes and both eyes are done the same day. The procedure is performed using topical anesthesia (eye drops). Some patients report a slight, post-operative discomfort that can usually be alleviated with medications. Patients see a dramatic improvement in their vision within the first day. Most patients return to their normal activities within a day or two.
Step by Step
The LASIK procedure takes a few minutes to complete, and the procedure is relatively painless. Patients are always amazed at the ease of this procedure because of speed and comfort. Only topical anesthetic drops are used to numb the eye for the procedure. An eyelid holder is inserted to prevent blinking while the drops eliminate the reflex to blink.
With LASIK, the surface epithelial layer is left intact, allowing for not only faster visual recovery but improved comfort and safety.
| Step 1 A suction ring is placed on the eye to secure the eye and maintain pressure within the eye while the corneal flap is created. A microkeratome, an automated microsurgical instrument similar in design to a carpenter’s plane, is used to create a thin corneal flap which remains hinged beneath the upper eyelid. The corneal flap is 160 to 180 microns thick, about 30% the corneal thickness which is typically about 550 microns. Patients do not feel or see the cutting of the corneal flap, which takes only a few seconds. Corneal “flap making” has been researched and developed for 40 years, providing us with a long history of safety and stability. |
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| Step 2 The corneal flap is then laid back and the inner stromal layers of the cornea lasered with the patient’s prescription. An ultraviolet light from the excimer laser reshapes the internal cornea with an accuracy of 1/2000th of a millimeter. For reshaping the cornea, the corneal surface is polished with the help of a pre-programmed excimer laser. This changes the refractive power of the cornea thus eliminating the refractive error of the eye. |
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| Step 3 The corneal flap is then repositioned and the flap and interface rinsed. Once the procedure is completed, the surgeon will wait 2 to 3 minutes to ensure the corneal flap has fully re-adhered. At this point, patients can blink normally and the corneal flap remains secured in position by the natural adherence within the cornea. While it is possible to dislodge the corneal flap during the first day or two by physically rubbing the eye, this event is actually quite rare. After the first week, LASIK patients can resume their full exercise activities.Since the protective layer remains intact with LASIK, no bandage or contact lens is required. However, a protective eye shield is normally recommended for a day. LASIK patients are placed on an antibiotic and anti-inflammatory drop regimen for about 1 week. They also need to instill artificial tears for a few months. Patients are able to travel by air immediately and exercise after 1 week.LASIK is generally considered the method of choice for using the Excimer Laser for correcting refractive errors. Another popular technique is Photo Refractive Keratectomy or PRK. Other variants of PRK include LASEK or Epi-LASIK. All of these procedures are offered at LaseRx. LASIK is generally the method of choice because it allows faster post-operative recovery of vision, requires less follow-up, and allows the patient to be more comfortable faster. However, there are circumstances under which it is more appropriate to use PRK in some patients. Your LaseRx eye surgeon will advise you appropriately. |