TY - JOUR
T1 - Corneal hydration and central islands after excimer laser photorefractive keratectomy
AU - Oshika, T.
AU - Klyce, S. D.
AU - Smolek, M. K.
AU - McDonald, M. B.
PY - 1998
Y1 - 1998
N2 - Purpose: To determine whether uneven corneal surface hydration during excimer laser photorefractie keratectomy (PRK) is related to postoperative occurrence of central islands. Setting: LSU Eye Center, New Orleans, Louisiana, USA. Methods: A retrospective study reviewed intraoperative videotapes and postoperative videokeratography of 49 eyes of 49 patients who had excimer laser PRK for myopia. The uniformity of corneal hydration within the photoablation zone, particularly the frosty appearance of the ablazed zone, was characterized. The presence or absence of a topographic central island (steepening of at least 3.0 diopters and 1.5 mm in diameter) was determined from the 1 month postoperative videokeratographs. Results: Twelve eyes (24.5%) developed central islands postoperatively. A statistically significant association was observed between the uneven surface hydration (central accumulation of fluid) within the ablation zone intraoperatively and the formation of central islands postoperatively (P < .001, Kruskal-Wallis test; Kendall τ rank correlation = 0.534; P < .001). Conclusion: Nonuniform fluid distribution during photoablation was a risk factor for central island formation after PRK. Intraoperatively, the presence of excess fluid in the central cornea appeared as a shiny area. This mirror-like surface layer may reduce the rate of central ablation by reflecting and absorbing a significant amount of the incident excimer laser light.
AB - Purpose: To determine whether uneven corneal surface hydration during excimer laser photorefractie keratectomy (PRK) is related to postoperative occurrence of central islands. Setting: LSU Eye Center, New Orleans, Louisiana, USA. Methods: A retrospective study reviewed intraoperative videotapes and postoperative videokeratography of 49 eyes of 49 patients who had excimer laser PRK for myopia. The uniformity of corneal hydration within the photoablation zone, particularly the frosty appearance of the ablazed zone, was characterized. The presence or absence of a topographic central island (steepening of at least 3.0 diopters and 1.5 mm in diameter) was determined from the 1 month postoperative videokeratographs. Results: Twelve eyes (24.5%) developed central islands postoperatively. A statistically significant association was observed between the uneven surface hydration (central accumulation of fluid) within the ablation zone intraoperatively and the formation of central islands postoperatively (P < .001, Kruskal-Wallis test; Kendall τ rank correlation = 0.534; P < .001). Conclusion: Nonuniform fluid distribution during photoablation was a risk factor for central island formation after PRK. Intraoperatively, the presence of excess fluid in the central cornea appeared as a shiny area. This mirror-like surface layer may reduce the rate of central ablation by reflecting and absorbing a significant amount of the incident excimer laser light.
UR - http://www.scopus.com/inward/record.url?scp=0031730546&partnerID=8YFLogxK
U2 - 10.1016/S0886-3350(98)80345-3
DO - 10.1016/S0886-3350(98)80345-3
M3 - Article
C2 - 9850893
AN - SCOPUS:0031730546
SN - 0886-3350
VL - 24
SP - 1575
EP - 1580
JO - Journal of Cataract and Refractive Surgery
JF - Journal of Cataract and Refractive Surgery
IS - 12
ER -