Jj. Peresantonja et al., CORNEAL ENDOTHELIAL CHANGES AFTER LASER IN-SITU KERATOMILEUSIS, Journal of cataract and refractive surgery, 23(2), 1997, pp. 177-183
Purpose: To ascertain whether 193 nm excimer laser in situ keratomileu
sis (LASIK) to correct high myopia causes in vivo changes in the human
corneal endothelium 3 and 6 months after surgery. Setting: Alicante I
nstitute of Ophthalmology, University of Alicante, Spain. Methods: Pre
operative and serial postoperative specular microscopy of the central
corneal endothelium was done in 33 eyes of 19 patients (Group I)with a
mean age of 34.3 years +/- 10.6 (SD) (range 20 to 60 years) who had L
ASIK to correct myopia of between 8.25 and 18.50 diopters (D) (mean 11
.90 +/- 2.20 D). Twelve patients (20 eyes) were contact lens wearers (
Group 2), and 7 (13 eyes) had never worn contact lenses (Group 3). The
central endothelium was analyzed for several parameters including cel
l density, coefficient of variation in cell size, and hexagonality. Th
e data obtained before surgery were compared with those obtained after
surgery in all groups. Results: There was no significant difference i
n age, sex, and preoperative myopia between Groups 2 and 3. In Group 1
, mean cell density was significantly higher (3.5%) 6 months after sur
gery (P = .017) and the coefficient of variation decreased 3 and 6 mon
ths after surgery (P < .001); no significant changes were noted in the
percentage of hexagonal cells. In Group 2, there was a significant in
crease in cell density (4.8%) 6 months after surgery (P = .010) and th
e coefficient of variation decreased at 3 and 6 months after surgery (
P < .001); the hexagonality did not change postoperatively. In Group 3
, there were no significant differences between preoperative and posto
perative mean cell density, coefficient of variation, or hexagonality.
Conclusion: Laser in situ keratomileusis caused no damage to the cent
ral corneal endothelium. Postoperative improvements in the endothelial
cell density and the coefficient of variation in cell size values wer
e related to the discontinuance of contact lens use after surgery.