Porcine model to compare real-time intraocular pressure during LASIK with a mechanical microkeratome and femtosecond laser.
OBJECTIVE
To compare real-time intraocular pressure (IOP) during laser in situ keratomileusis (LASIK) in porcine eyes using two types of microkeratomes.


METHODS
An interventional, prospective study of two microkeratomes: a Moria 2 (Moria group) and an IntraLase femtosecond laser (IntraLase Corp., Irvine, CA; IntraLase group). These devices were used to create lamellar corneal flaps in freshly enucleated porcine eyes. The IOP changes induced by the procedures were recorded with a reusable blood pressure transducer connected to the anterior chamber by direct cannulation.


RESULTS
Seven porcine eyes were studied in each group. The IOP increased during the suctioning phase, reaching a mean of 122.52 +/- 30.40 and 160.52 +/- 22.73 mm Hg during the cutting phase in the Moria group (the total time in this group was 36.42 +/- 7.48 seconds; suctioning required 21.42 +/- 7.48 seconds and the cutting phase, 15 +/- 2.88 seconds). In the IntraLase group, the IOP reached 89.24 +/- 24.26 mm Hg during the suctioning phase and 119.33 +/- 15.88 mm Hg during the intrastromal laser application (the total time was 92.85 +/- 13.49 seconds; suctioning required 40.00 +/- 9.57 seconds and the cutting phase 52.85 +/- 5.66 seconds). Both IOPs during both phases differed significantly between the two groups (P = 0.01 for all comparisons).


CONCLUSIONS
Real-time IOP can be measured during LASIK using a transducer connected to the anterior chamber. The results showed a significant increase in IOP during the procedure in both groups, although with the IntraLase the IOP seemed to increase to a lesser extent than with the conventional mechanical microkeratome.
Hernández-Verdejo
José L
JL
Vissum Hospital Oftalmológico, Madrid, Spain.
Teus
Miguel A
MA
Román
José M
JM
Bolívar
Gema
G
D000818:Animals; D003199:Computer Systems; D003319:Corneal Stroma / Q000601:surgery; D007429:Intraocular Pressure / Q000502:physiology*; D020731:Keratomileusis, Laser In Situ; D007834:Lasers; D023421:Models, Animal; D011446:Prospective Studies; D013396:Suction / Q000295:instrumentation; D013524:Surgical Flaps; D013552:Swine; D014065:Tonometry, Ocular / Q000295:instrumentation