AIM:To compare the safety and efficacy of conventional versus accelerated(9 mW/cm^2)corneal collagen crosslinking(CXL)in progressive keratoconus at the 2-year follow-up.METHODS:In this prospective study,consecutive pr...AIM:To compare the safety and efficacy of conventional versus accelerated(9 mW/cm^2)corneal collagen crosslinking(CXL)in progressive keratoconus at the 2-year follow-up.METHODS:In this prospective study,consecutive progressive keratoconus patients were randomized to receive either conventional CXL(CCXL)or accelerated CXL(ACXL;using hydroxypropyl methylcellulose-assisted riboflavin imbibition for 10 min at 9 mW/cm^2).Visual,refractive,keratometric,topographic,and aberrometric outcomes and stromal demarcation line depth(DLD)measurements were compared at the end of a 2-year follow-up.RESULTS:Thirty-two eyes from 32 patients in the CCXL and 27 eyes from 27 patients in the ACXL groups completed 2-year follow-up.At 2y post-CXL,both uncorrected and corrected visual acuities improved significantly in both groups.The improvements in keratometric readings,flattening rate(flattening of the maximum keratometry more than 1 D),3 topographic indices,and vertical coma were significantly better in the CCXL group compared to the ACXL group(P<0.05).The DLD as measured by anterior segment optical coherence tomography or in vivo confocal microscopy was better detectable and significantly deeper in the CCXL group compared to the ACXL group.The deeper DLD was found to be significantly correlated with improvements in the mean keratometry measurements.Progression was noted in 11.1%of eyes in the ACXL group,whereas progression was not observed in any patient eye in the CCXL group.CONCLUSION:In this prospective randomized study,ACXL is less effective in halting the progression of keratoconus at a 2-year follow-up compared to CCXL.展开更多
Background:To compare the outcomes of two different protocols of accelerated corneal crosslinking(CXL)on visual,corneal high order aberrations(HOA)and topographic parameters in patients with progressive keratoconus.Me...Background:To compare the outcomes of two different protocols of accelerated corneal crosslinking(CXL)on visual,corneal high order aberrations(HOA)and topographic parameters in patients with progressive keratoconus.Methods:In this prospective comparative study,sixty-six eyes of 66 patients with progressive keratoconus were divided into two groups;37 eyes in Group 1 received 18 mW/cm^(2) for five minutes,and 29 eyes in Group 2 were treated with 9 mW/cm^(2) for 10 min.The uncorrected distant visual acuity(UCVA),best-corrected distant visual acuity(BCVA),corneal HOAs and topography parameters were measured preoperatively and postoperatively at the end of 12 months.The data for the two groups were compared statistically.Results:The mean UCVA and BCVA were significantly improved at the postoperative 12 months compared with the preoperative values in both groups(P<0.05 for all).A significant improvement in corneal HOAs was observed in both groups(P<0.05 for all).The change in corneal coma value was significantly higher in Group 2(P<0.05).The change in keratometric values K1,K2,AvgK and maximum keratometry(AKf)were significantly higher in Group 2(P<0.05 for all).The regression model showed that the most important factor predicting the change in AKf was the type of CXL(β=−0.482,P=0.005).Conclusions:Accelerated CXL using 10 min of UVA irradiance at 9 mW/cm^(2) showed better topographic improvements and coma values than five minutes of UVA irradiance at 18 mW/cm^(2) independent of keratoconus severity.展开更多
文摘AIM:To compare the safety and efficacy of conventional versus accelerated(9 mW/cm^2)corneal collagen crosslinking(CXL)in progressive keratoconus at the 2-year follow-up.METHODS:In this prospective study,consecutive progressive keratoconus patients were randomized to receive either conventional CXL(CCXL)or accelerated CXL(ACXL;using hydroxypropyl methylcellulose-assisted riboflavin imbibition for 10 min at 9 mW/cm^2).Visual,refractive,keratometric,topographic,and aberrometric outcomes and stromal demarcation line depth(DLD)measurements were compared at the end of a 2-year follow-up.RESULTS:Thirty-two eyes from 32 patients in the CCXL and 27 eyes from 27 patients in the ACXL groups completed 2-year follow-up.At 2y post-CXL,both uncorrected and corrected visual acuities improved significantly in both groups.The improvements in keratometric readings,flattening rate(flattening of the maximum keratometry more than 1 D),3 topographic indices,and vertical coma were significantly better in the CCXL group compared to the ACXL group(P<0.05).The DLD as measured by anterior segment optical coherence tomography or in vivo confocal microscopy was better detectable and significantly deeper in the CCXL group compared to the ACXL group.The deeper DLD was found to be significantly correlated with improvements in the mean keratometry measurements.Progression was noted in 11.1%of eyes in the ACXL group,whereas progression was not observed in any patient eye in the CCXL group.CONCLUSION:In this prospective randomized study,ACXL is less effective in halting the progression of keratoconus at a 2-year follow-up compared to CCXL.
文摘Background:To compare the outcomes of two different protocols of accelerated corneal crosslinking(CXL)on visual,corneal high order aberrations(HOA)and topographic parameters in patients with progressive keratoconus.Methods:In this prospective comparative study,sixty-six eyes of 66 patients with progressive keratoconus were divided into two groups;37 eyes in Group 1 received 18 mW/cm^(2) for five minutes,and 29 eyes in Group 2 were treated with 9 mW/cm^(2) for 10 min.The uncorrected distant visual acuity(UCVA),best-corrected distant visual acuity(BCVA),corneal HOAs and topography parameters were measured preoperatively and postoperatively at the end of 12 months.The data for the two groups were compared statistically.Results:The mean UCVA and BCVA were significantly improved at the postoperative 12 months compared with the preoperative values in both groups(P<0.05 for all).A significant improvement in corneal HOAs was observed in both groups(P<0.05 for all).The change in corneal coma value was significantly higher in Group 2(P<0.05).The change in keratometric values K1,K2,AvgK and maximum keratometry(AKf)were significantly higher in Group 2(P<0.05 for all).The regression model showed that the most important factor predicting the change in AKf was the type of CXL(β=−0.482,P=0.005).Conclusions:Accelerated CXL using 10 min of UVA irradiance at 9 mW/cm^(2) showed better topographic improvements and coma values than five minutes of UVA irradiance at 18 mW/cm^(2) independent of keratoconus severity.
