The Laser
The number of lasers used in LASIK have grown in numbers over the past decade and there are specialized lasers used for many different types of vision correction. Lasers have been developed to address the needs of patients that have thinning corneas and other issues that previously made certain people unable to quality for laser eye surgery.
Excimer lasers, designed for laser-assisted in situ keratomileusis (LASIK), are the laser of choice for most basic laser surgeries.
There are also more specialized lasers - here is a brief overview.
Although all approved lasers meet safety and effectiveness criteria established by the FDA, certain people may be better off with one type of laser over another, an experienced doctor of LASIK will be able to advise the best type of laser for your own vision correction needs.
Types of Modern Excimer Lasers Used for LASIK
Slit scanning lasers - Slit scanning lasers use small beams linked to a rotational device with slit holes that enlarge. The laser beams scan across these holes during surgery, producing a gradually enlarging zone. The approach provides a uniform beam and potentially a smoother surface. The only drawback is overcorrection (too much roundness of the cornea) can be achieved.
Spot scanning lasers - Spot scanning (or "flying-spot") lasers, which are the most common in use presently, use small-diameter laser beams and are scanned across the cornea. The type of approach during the laser eye surgery produces some of the smoothest surfaces and is often the laser of choice to treat irregular astigmatism (where the eyes have different correction needs).
Wavefront-guided lasers - Many excimer lasers are connected to a device that detects and maps the eye's optical system and shows how lightwaves travel through the eye. Wavefront devices show a great picture of how a cornea should be reshaped during the laser eye surgery.
Approval Number for a particular laser will connect you to another FDA page with links to the Approval Order, Indications for Use, the Summary of Safety and Effectiveness (SSE) and the Labeling for Physician and Patient (labeling is often combined into one document with the patient labeling following the physician labeling).
| Company and model | Approval number and date | Approved indications (D = diopters) |
| AutonomousTechnology - LADARVision | P970043/S5 5/9/00 | Myopia less than -9.0D with or without astigmatism from -0.5 to -3.0D |
| Bausch& Lomb Surgical - Technolas 217a | P990027 2/23/00 | Myopia from -1.0 to -7.0D with or without astigmatism less than – ;3.0D |
| Bausch & Lomb Surgical - Technolas 217a | P990027/S2 5/15/02 | Myopia less than -11D with or without astigmatism less than – 3.0D |
| Dishler | P970049 12/16/99 | Myopia from -0.5 to -13.0D with or without astigmatism between -0.5 to -4.0D |
| Kremer | P970005 7/30/98 | Myopia from -1.0 to -15.0D with or without astigmatism up to -5.0D |
| LaserSight - LaserScan LSX | P980008/S5 9/28/01 | Myopia from -0.5 to -6.0D with or without astigmatism up to 4.5D |
| Nidek - EC5000 | P970053/S2 4/14/00 | Myopia from -1.0 to -14.0D with or without astigmatism less than 4.0D |
| Summit - Apex Plus | P930034/S13 10/21/99 | Myopia less than -14.0D with or without astigmatism from 0.5 to 5.0D |
| Summit Autonomous - LADARVision | P970043/S7 9/22/00 | Hyperopia less than 6.0D with or without astigmatism less than -6.0D |
| VISX - Star S2 & S3 | P930016/S12 4/27/01 | Hyperopia between +0.5 and +5.0D with or without astigmatism up to +3.0D |
| VISX - Star S2 & S3 | P930016/S14 11/16/01 | Mixed astigmatism up to 6.0D ; cylinder is greater than sphere and of opposite sign |
| VISX - Star S2 | P990010 11/19/99 | Myopia less than -14.0D with or without astigmatism between -0.5 and -5.0D |
| VISX - Star S3 (EyeTracker) | P990010/S1 4/20/00 | Same as S2, except with eye tracker |
| Autonomous Technology - LADARVision | P970043 11/2/98 | PRK ; Myopia from -1.0 to -10.0D with or without astigmatism less than -4.0D |
| Bausch & Lomb Surgical - KERACOR 116 | P970056 9/28/99 | PRK ; Myopia from -1.5 to -7.0D with or without astigmatism less than -4.5D |
| LaserSight - LaserScan LSX | P980008 11/12/99 | PRK ; Myopia from -1.0 to -6.0D with or without astigmatism less than 1.0D |
| Nidek - EC5000 | P970053 12/17/98 | PRK ; Myopia from -0.75 to -13.0D |
| Nidek - EC5000 | P970053/S1 9/29/99 | PRK ; Myopia from -1.0 to -8.0D with or without astigmatism from -0.5 to -4.0D |
| Summit - Apex & Apex Plus | P930034 10/25/95 | PRK ; Myopia from -1.5 to -7.0D |
| Summit - Apex Plus | P930034/S9 3/11/98 | PRK ; Myopia from -1.0 to -6.0D with or without astigmatism from -1.0 to -4.0D |
| Summit - Apex Plus | P930034/S12 10/21/99 | PRK ; Hyperopia from +1.5 to +4.0D with or without astigmatism less than -1.0D |
| Summit Autonomous - LADARVision | P970043/S8 7/11/00 | Name Change Only |
| Sunrise - Hyperion | P930016 3/27/96 | Laser Thermokeratoplasty (LTK) ; Hyperopia from +0.75 to +2.5D with or without astigmatism less than 0.75D |
| VISX - Model B & C (Star & Star S2) | P930016/S3 4/24/97 | PRK ; Myopia from 0 to -6.0D |
| VISX - Model B & C (Star & Star S2) | P930016/S5 1/29/98 | PRK ;Myopia from 0 to -6.0D with or without astigmatism from -0.75 to -4.0D |
| VISX - Model B & C (Star & Star S2) | P930016/S7 11/2/98 | PRK ; Myopia from 0 to -12.0D with or without astigmatism from 0 to -4.0D |
| VISX - Star S2 | P930016/S10 10/18/00 | PRK ;Hyperopia from +1.0 to +6.0D |
| VISX - Star S2 & S3 | P930016/S13 3/19/01 | PRK ; Hyperopia from +0.5 to +5.0D with or without astigmatism +0.5 to +4.0D |
U.S. Food and Drug Administration, Center for Devices and Radiological Health
