Purpose: To prospectively evaluate inflammatory response by measuring aqueous flare in the anterior chamber after photorefractive keratectomy (PRK), laser in situ keratomileusis (LASIK), and intracorneal ring segments (ICRS) implantation.
Methods: Aqueous flare was measured pre- and postoperatively at days 1, 7, and 21 with a laser flare meter (Kowa FM 500). Thirty-one patients (58 eyes) were randomized, only for low myopia, in three groups treated with PRK (myopia <-4.50 D), LASIK (myopia range between -4.00 and -12.00 D), and ICRS (myopia <-4.50 D).
Results: Mean preoperative flare intensities were similar in the three groups (p< or =0.05; mean, 4.6 photons/ms). In the PRK group, flare increased significantly (mean day 2, 9.5 photons/ms), as it did in the LASIK group (mean day 1, 23.8 photons/ms). In the ICRS group, there was no significant difference between pre- and postoperative levels of flare at any time (mean day 1, 4.9 photons/ms). In all three groups, flare intensity returned to baseline at day 7, except in the LASIK group, which remained at a significantly higher level (mean day 7, 7.7 photons/ms) than the preoperative one.
Conclusions: According to this method, the blood-aqueous barrier seems to be altered in laser procedures, particularly in LASIK, probably in correlation with the depth of photoablation. ICRS implantation did not increase the postoperative flare significantly.