Our patients have numerous choices regarding advanced technology and eye care. Advances range from how patients check in for an appointment to what tools a surgeon uses to dissect tissue. They all have their benefits, and all come at a cost.
One of the most disruptive, new technologies—both figuratively and literally—is the femtosecond laser (FSL). It is more advanced than robotic surgery in which a computer program tells the laser where to make the cut without a surgeon having to touch an eye.
FSL is one millionth of a billionth of a second, and the laser operates in the infrared wavelengths ranging from 1,030 nm to 1,053 nm. The laser uses the principle of photoionization vaporizing a small volume of tissue.1
Previously from Dr. Owen: How to manage vision changes over time post-LASIK
By lining up these tiny explosions, the laser can create a cleavage plane to separate tissue. The byproduct of this process is mostly carbon-dioxide and water vapor. FSL has the ability to “arrange” the cavitation bubbles in the exact location to separate tissue.2
The first FSL was approved to create a corneal flap for LASIK in 2001. In 2017, the FSL expanded its utility and use to cataract surgery for making incisions, capsulrhexis, liquefying the crystalline lens, and treating astigmatism.
FSL’s role in the cornea has also expanded to removing lenticules for correcting myopia, creating channels for intrastromal rings, making cuts in both the donor and host tissue for penetrating keratoplasty, and lamellar keratoplasty. A mechanical microkeratome may raise the intraocular pressure to as high as 100 mm Hg and advances a diamond blade across the cornea.
While complications are relatively rare, they can have a dramatic impact on a patient’s clinical outcome. Incomplete flaps, free caps, irregular flaps, and decentered flaps can decrease significantly with the use of FSL.3
FSL creates a planar flap at a more precise depth. Thinner flaps with less deviation from the intended thickness allow the surgeon to comfortably treat higher refractive errors with fewer biomechanical changes.4
The precision of FSL allows for variable flap diameters, increased side-angle cuts, and fewer epithelial defects. These improvements have resulted in few flap displacements, less epithelial in growth, improved corneal sensitivity, and less dry eye.5,6