title: One-year outcomes of conventional and accelerated collagen crosslinking in progressive keratoconus.
abstract: We compared one-year outcomes of conventional (3 mW/cm(2), 365-nm ultraviolet-A light, 30 minutes) and accelerated (18 mW/cm(2), 365-nm ultraviolet-A light, 5 minutes) collagen crosslinking (CXL) in patients with progressive keratoconus. Main outcome measures were change in keratometry, uncorrected visual acuity (UCVA), and best-corrected visual acuity (BCVA). Nineteen patients in each group completed 1-year follow-up. Preoperatively, there were no inter-group differences for age, keratometry, corneal thickness, and spherical equivalent (p > 0.127). One year postoperatively, maximum and minimum keratometry were flattened by 1.6 diopters (p < 0.023) and 2 diopters (p < 0.047) respectively after conventional CXL, and, 0.47 diopters (p = 0.471) and 0.19 diopters (p = 0.120) respectively after accelerated CXL. Association analysis showed significant negative association between baseline maximum keratometry and change in maximum keratometry after accelerated CXL (p = 0.002) but not after conventional CXL (p = 0.110). Corneal thickness was reduced significantly in both groups (p = 0.017). An improvement in UCVA (p < 0.001) and BCVA (p < 0.022) was noted in both groups along with a reduction in spherical equivalent postoperatively (p < 0.026). There were no inter-group differences for any of the parameters postoperatively (p > 0.184). Although no statistically significant differences were observed between both treatment modalities, a more effective topographic flattening was observed with conventional CXL as compared to accelerated CXL in this study.
authors.affiliation: Hong Kong Eye Hospital, Hong Kong SAR, China.|Department of Ophthalmology &Visual Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Vanissa W S
authors.initials: VW
authors.lastname: Chow
authors.affiliation: Hong Kong Eye Hospital, Hong Kong SAR, China.|Department of Ophthalmology &Visual Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Tommy C Y
authors.initials: TC
authors.lastname: Chan
authors.affiliation: Department of Mathematics and Statistics, Hang Seng Management College, Hong Kong.
authors.forename: Marco
authors.initials: M
authors.lastname: Yu
authors.affiliation: Hong Kong Eye Hospital, Hong Kong SAR, China.|Department of Ophthalmology &Visual Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Victoria W Y
authors.initials: VW
authors.lastname: Wong
authors.affiliation: Hong Kong Eye Hospital, Hong Kong SAR, China.|Department of Ophthalmology &Visual Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Vishal
authors.initials: V
authors.lastname: Jhanji
mesh_terms: D000293:Adolescent; D000328:Adult; D003094:Collagen / Q000378:metabolism*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D063868:Patient Outcome Assessment; D013997:Time Factors; D055815:Young Adult
chemical_list: D003094:Collagen