The Latest in LASIK: iLASIK
In May, 2005, Advanced Medical Optics, Inc. (AMO) finalized its acquisition of VISX, Inc. Both of these companies had been leaders in the field of medical devices, especially ophthalmic technology.
- VISX was pre-eminent in LASIK technology with its CustomVue™ WaveFront system
- AMO was offering the IntraLase™ FS Laser, blink® eyedrops, ReZoom™ multifocal IOL (intraocular lens), and many other products
The merging of these two companies has lead to the merging of their various technologies and medical devices, and this has given us iLASIK: a combination of IntraLase and CustomVue.
What is IntraLase™?
Since it was first developed and then approved by the FDA, LASIK has never been a good option for everybody. A qualified and experienced LASIK surgeon will always screen his or her patients very carefully, so as to avoid performing an inappropriate procedure. At first this meant that many people could not have refractive surgery because their eyes did not have parameters acceptable for safety.
In the ten or so years since FDA approval, ophthalmologists have devised various ways of delivering LASIK such that it is safe and effective for a larger pool of candidates. IntraLase is one of those alternatives.
What’s the Flap About?
After LASIK, the most frequent complications (although they’re rare these days) arise from the corneal flap which is created at the beginning of the procedure. Refractive surgery is not done on the corneal surface. That would not be sensible or practical, because the corneal epithelium (top surface) is continually discarding and replacing cells. Any change made to it would not necessarily be permanent.
That’s why a LASIK procedure first creates a thin corneal flap and folds it back out of the way. This gives access to the next layer down, the stroma, which is stable and will stay changed after your procedure.
So the thickness and contour of your cornea is particularly important in determining your candidacy for LASIK. If you have corneas which are too thin, or if you are too severely myopic, LASIK would not be safe. The cornea needs:
- Enough thickness to allow for the flap plus the ablation (removal of tissue for recontouring), and still have enough thickness left to hold strong against the eye’s internal pressure without bulging forward;
- Enough flatness to allow the microkeratome to safely create the flap without cutting too deeply. A severely myopic eye has a steep curvature.
This is one of the names for IntraLase because it does not use the microkeratome to create the flap. Instead it uses a second laser. Why does this help? Well, the laser is pulsed super-fast. It can be set to penetrate the cornea at a specific depth, not too deep for the eyes of someone who doesn’t qualify for standard LASIK. Super-fast pulses are directed at the planned treatment area and each pulse makes a microscopically tiny bubble at the pre-set depth. Each bubble is a loosening of the molecular bonds holding corneal tissue together.
In a few seconds this laser covers the entire treatment area, back and forth, making bubbles until an entire flap is loosened and can be easily lifted. The treatment plan has allowed for enough corneal thickness to remain after treatment, and the flap can be replaced after treatment to heal up as in a traditional LASIK surgery.
So IntraLase is the first component of iLASIK. Please see the next page for the second component, CustomVue