http://www.nomi.med.navy.mil/NAMI/Wa...rch 2007.pdf
Secion 12.15:
Definitions:
Corneal Refractive Surgery (CRS): A laser is used to reshape the anterior corneal surface reducing refractive error and reliance on spectacles or contact lenses. A “wavefront-guided” (WFG) or “custom” procedure uses wavefront analysis technology to perform the procedure.
Photorefractive Keratectomy (PRK) or Surface Ablation or Advanced Surface Ablation (ASA): Laser energy is applied to the anterior corneal surface after the epithelium is temporarily displaced or removed. No corneal flap is created.
PRK variants include LASEK (epithelium is preserved), and Epi-LASIK (epithelial flap is created).
Laser in-situ keratomileusis (LASIK): A corneal flap is created with a surgical blade or laser after which additional laser energy is applied to the exposed corneal tissue underneath the flap. The flap is then repositioned.
CAUTION:
Brand names, marketing strategies and technological advances often cause confusion regarding CRS terminology.