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AIM:To evaluate corrective effect and stability of corneal morphology in patients with moderate to high myopia after 2a treatment of femtosecond laser assisted laser in situ keratomileusis(FS-LASIK)Xtra.METHODS:Retrospective case-control study. A total of 30 cases(58 eyes)Patients with moderate to high myopia combined with astigmatism who planned to undergo refractive surgery in our hospital from August 2019 to August 2020 were included, and different types of surgery were performed respectively based on the relevant index of keratoconus screening in the preoperative corneal topography. They were divided into FS-LASIK group and Xtra group, with 15 cases(29 eyes)in each group. Uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), spherical equivalent(SE)and the corneal curvature of the anterior and posterior surfaces of different diameters(3, 5 and 7 mm)measured by Sirius three-dimensional corneal topography were observed preoperatively and 3 mo, 1 and 2 a postoperatively.RESULTS: The UCVA of the two groups of patients at different time points after surgery was significantly increased compared with preoperatively(both P<0.01), and there was no difference in UCVA and SE between the two groups(P>0.05). After 2 a postoperatively, residual astigmatism was -0.25-0 D in 25 eyes(86%)of the FS-LASIK Xtra group and 24 eyes(83%)of the FS-LASIK group. The actual corrected SE and expected corrected SE of both groups were positively correlated(both P<0.05). There were differences in corneal curvature on the surface of different diameter areas(3, 5, and 7 mm)between the two groups at 3 mo, 1, and 2 a postoperatively compared with preoperatively. After 1 and 2 a postoperatively, the corneal posterior surface curvature of the FS-LASIK Xtra group with corneal diameter of 3 and 5 mm was higher than that of the FS-LASIK group(P<0.05).CONCLUSIONS:FS-LASIK Xtra has good safety, efficacy and predictability in correcting patients with moderate to high myopia.
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AIM: To investigate the efficacy of epithelial-off accelerated corneal cross-linking(CXL)in the treatment of advanced keratoconus.METHODS: A retrospective study was performed on data collected from 32 patients(43 eyes)with advanced keratoconus who underwent epithelial-off accelerated CXL at Ningxia Eye Hospital from April 2020 to December 2021. Slit-lamp, intraocular pressure, uncorrected visual acuity(UCVA), corrected visual acuity, specular microscope, Pentacam and Corvis ST were tested before and at 1, 3 and 6mo after surgery. Preoperative and postoperative corneal condition, UCVA, best corrected visual acuity(BCVA)and the values of corneal endothelial, maximum keratometry(Kmax), thinnest corneal thickness(TCT), anterior and posterior surfaces of the cornea K1, K2, biomechanically corrected intraocular pressure(bIOP), applanation time 1(A1T), applanation length 1(A1L), applanation velocity 1(A1V), applanation time 2(A2T), applanation length 2(A2L), applanation velocity 2(A2V), highest concavity deformation amplitude(HCDA), radius at highest curvature(HCR), highest concavity peak distance(HCPD)and stiffness parameter at first applanation(SP-A1)were recorded.RESULTS: There were differences between UCVA(LogMAR; 1.06±0.49, 0.78±0.39)and BCVA(LogMAR; 0.48±0.34, 0.38±0.29)before and at 6mo after surgery(P<0.05), but there were no differences in corneal endothelial cells(2917.39±288.38 vs. 2959.19±336.27 cells/mm2, P=0.477). There were differences among Kmax, TCT, anterior surface K1 and K2 and posterior surface K1 before and after surgery(P<0.05), and all increased at 1mo after surgery then returned to preoperative level at 3mo after surgery, while there was no difference in the posterior K2. Furthermore, there were statistical significance in A1T, HCPD and SP-A1 before and after surgery(P<0.05), while there were no statistical significance in A1L, A1V,A2T, A2L, A2V, HCDA, HCR and bIOP(P>0.05).CONCLUSION: Epithelial-off accelerated CXL can prevent the progression of keratoconus within half year after surgery, and it has certain safety.
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Objective:To investigate the efficacy and safety of accelerated epithelium-off corneal collagen cross-linking (CXL) in the treatment of corneal ectasia after keratorefractive surgery.Methods:An observational case series study was performed.Twelve patients (22 eyes) diagnosed with corneal ectasia after keratorefractive surgery in the First Affiliated Hospital of Army Medical University were enrolled from January 2016 to December 2018.All the patients received accelerated epithelium-off CXL and were followed up for 12 months.Before and 1 week, 1, 3, 6, and 12 months after the operation, the uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) converted to the logarithm of the minimum angle of resolution (LogMAR) unit were measured.The sphericity, cylindricity, and spherical equivalent were examined by Topcon auto refractor.The maximum keratometry (Kmax) of the front surface, mean keratometry (Km) of the front surface, Km of the back surface, symmetry index of front surface (SIf), symmetry index of back surface (SIb), thinnest corneal thickness (TCT), total aberrations, total high-order aberrations, coma aberration, trefoil aberration and spherical aberration were detected by the Sirius analyzer.The depth of corneal demarcation lines was determined by optical coherence tomography.The intraocular pressure was measured by the non-contact tonometry.The corneal endothelial cell density was assayed by the endothelial cell densitometry.The inflammatory reaction and haze were observed with a slit lamp at different time points after surgery.This study adhered to the Declaration of Helsinki.The study protocol was approved by the First Affiliated Hospital of Army Medical University (No.KY2020063). Written informed consent was obtained from each patient before entering the cohort.Results:Among the 22 eyes of 12 cases, 3 eyes of 2 cases (13.64%) underwent small incision lenticule extraction, and 19 eyes of 10 cases (86.36%) underwent excimer laser in situ keratomileusis.The UCVA (LogMAR), BCVA (LogMAR), cylindricity and spherical equivalent before the operation were 0.61±0.42, 0.24±0.23, (-2.83±2.39)D, (-3.60±2.66)D, which were significantly worse than 0.45±0.31, 0.12±0.15, (-2.11±1.67)D, (-3.12±2.31)D at 12 months after the operation ( t=4.054, 4.956, -3.728, -2.742; all at P<0.05). The front surface Kmax, front surface Km and SIf at 12 months after the operation were (48.37±5.80), (41.49±3.04), (5.36±4.07)D, which were significantly lower than (49.61±5.97), (41.66±2.97), (5.85±4.18)D before the operation ( t=5.949, 2.278, 2.719; all at P<0.05). There was no significant difference in sphericity, Km of the back surface, SIb, TCT, total aberrations, total high-order aberrations, coma aberration, trefoil aberration, spherical aberration, intraocular pressure and endothelial cell density between before and 12 months after the operation (all at P>0.05). Grade 0.5-2 haze occurred in 8 eyes of 4 patients one month postoperatively.After administration of prednisolone acetate eye drops, haze decreased or disappeared 3 months postoperatively, with UCVA and BCVA unchanged.A corneal demarcation line with a depth of (285.40±51.61)μm was found in 11 eyes of 6 cases at 1 month after operation. Conclusions:Accelerated epithelium-off CXL can significantly improve visual acuity, reduce corneal astigmatism and corneal curvature, as well as effectively prevent the progress of corneal ectasia.
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Purpose: To monitor the changes in the ABCD grading system during a one?year follow?up after a corneal cross?linking (CXL) procedure. Methods: This prospective study included 30 eyes of 25 patients with keratoconus, who received the CXL treatment. The patients with a history of ocular trauma or surgery and other corneal pathology were excluded from the study. The patients were examined at the baseline visit and followed up at 3, 6, and 12 months after the CXL. All the patients underwent a standard CXL procedure with visual acuity and Scheimpflug tomography testing at each visit. The corneal parameters and ABCD grading were monitored throughout the follow?up period. Results: There were no significant changes of parameter A and anterior radius curvature (ARC) in the ABCD grading system. Parameters B and D showed progression postoperatively, with an improvement of parameter D on the final visit. Parameter C showed a statistically significant increase at all three post?CXL visits, but a constant gradual decrease in the value over time. Conclusion: The ABCD grading system can be very useful in monitoring the progression of keratoconus (KC), but it can also help in monitoring the efficacy of corneal cross?linking. The anterior surface parameters in the ABCD grading system did not show progression in the post?CXL period, and parameters C and D showed improvement and stability a year after the procedure.
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@#AIM:To evaluate the repeatability and comparison of corneal visualization scheimpflug technology(Corvis ST)parameters in keratoconus eyes before and after accelerated transepithelial corneal cross-linking(ATE-CXL).<p>METHODS: Thirty eyes of 30 progressive keratoconus patients were included in the prospective study. Three repeated corneal biomechanical measurements were performed preoperatively and one month postoperatively by Corvis ST. The interclass correlation coefficient(ICC)and 95% confidence interval(<i>CI</i>), Cronbach'α, repeatability coefficient(RC), and coefficient of variation(CV)were used to evaluate the repeatability of Corvis ST parameters. Paired <i>t</i>-test or Wilcoxon rank test was used to evaluate the differences between preoperative and postoperative data.<p>RESULTS: At preoperative, 26 of 39(66.67%)parameters showed good to excellent repeatability, 6(15.38%)showed moderate, and 7(17.95%)showed poor repeatability. Similarly, 34(87.18%)parameters showed good to excellent repeatability, 3(7.69%)showed moderate, and 2(5.13%)showed poor repeatability after ATE-CXL. After ATE-CXL 1mo, the intraocular pressure(IOP), biomechanical corrected IOP(bIOP), first applanation time(A1T), Radius, deformation amplitude at the first applanation(A1DA), deflection length at the maximum deformation(HCDLL)and stiffness parameter at first applanation(SP A1)parameters increased, while the steep keratometry(Ks), flat keratometry(Kf), mean keratometry(Kmean), second applanation time(A2T), DA Ratio Max(2 mm)and integrated radius parameters decreased(all <i>P</i><0.05). <p>CONCLUSION:The repeatability of the Corvis ST parameters before and 1mo ATE-CXL follow up were both acceptable, and the corneal stiffness was improved after 1mo ATE-CXL.
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@#AIM: To investigate the clinical effect of transepithelial rapid cross-linking combined with wearing rigid gas permeable contact lens(RGPCL)in keratoconus patients.<p>METHODS: This was a retrospective study of patients with progressive keratoconus diagnosed in the Second Affiliated Hospital of Fujian University of Traditional Chinese Medicine in October 2014, and underwent transepithelial rapid keratoplasty. After surgery 16 patients(25 eyes)used RGPCL. Average age was 25.31±5.92 years old, maximum preoperative corneal curvature was 58.96±6.76D, thinnest corneal thickness was 439.52±53.24μm. Rapid cross-linking was performed using riboflavin and 45mW/cm<sup>2</sup> ultraviolet light(UV)irradiation with a total energy of 7.2J/cm<sup>2</sup>. RGPCL was used after surgery. Follow up of 3-6a, average follow-up time was 52.44±11.39mo. The best corrected visual acuity \〖(BCVA), in RGPCL\〗, corneal curvature of flat meridian(K<sub>1</sub>), corneal curvature of steep meridian(K<sub>2</sub>), maximum corneal curvature(Kmax), corneal refractive power(MPP), Baiocchi Calossi Versaci index of anterior and posterior surface(BCVf and BCVb)asymmetry index of anterior surface curvature(SIf), asymmetry index of posterior surface curvature(SIb), the highest point of anterior cone cornea(KVf), the highest point of posterior cone cornea(KVb), the change of corneal thickness(ThkMin), lens opacity, and corneal endothelial cell count were observed.<p>RESULTS: All patients had a successful operation, and no intraoperative complications. On the first day after surgery, all cases felt slight tingling and slight photophobia tears. After 1d of operation, the corneal epithelium was removed in two eyes. While 3d after re-wearing the bandage, the epithelium healed. None of lens in the patients was opacified during follow-up, and there was no significant difference in corneal endothelial cell count compared with preoperative(<i>P</i>>0.05). The BCVA(wearing RGPCL)after operation is obviously improved compared with preoperative. All postoperative Kmax, SIf, KVf, BCVf, BCVb were lower than preoperative(<i>P</i><0.05). <p>CONCLUSION: Transepithelial rapid corneal cross-linking combined with RGPCL is safe and effective in controlling the progress of keratoconus. And the long-term effect is stable.
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ABSTRACT Purpose: To evaluate the effect of accelerated corneal crosslinking on corneal biomechanics with an ocular response analyzer in patients with progressive keratoconus. Methods: In this retrospective study, 50 eyes of 45 patients with progressive keratoconus who underwent accelerated corneal crosslinking were evaluated with ocular response analyzer waveform parameters before and one year after corneal crosslinking. Paired two-tailed Student's t-test was performed to compare the parameters before vs. after corneal crosslinking. Results: Mean patient age was 17.6 ± 3.6 (range 9-25) years. A significant increase was observed in p1 area, p2 area, h2, and dive2 values. No significant difference in corneal hysteresis, corneal resistance factor, or other waveform-derived parameters was observed at one year postoperatively. Conclusion: For estimating the effect of accelerated corneal crosslinking on corneal biomechanics, parameters such as p1 area, p2 area, h2, and dive2 are more sensitive than corneal hysteresis and corneal resistance factor. These results may help us to find out which corneal crosslinking method is most effective for stiffening the cornea.
RESUMO Objetivo: Avaliar o efeito do cross-linking corneano acelerado na biomecânica corneana com analisador de resposta ocular em pacientes com ceratocone progressivo. Métodos: Neste estudo retrospectivo, 50 olhos de 45 pacientes com ceratocone progressivo submetidos à cross-linking corneano acelerado foram avaliados com os parâmetros da forma de onda do analisador de resposta ocular antes e um ano após o tratamento com cross-linking corneano. O teste t de Student pareado bicaudal foi realizado para comparar os parâmetros antes e depois do cross-linking corneano. Resultados: A média de idade dos pacientes foi de 17,6 ± 3,6 (variação de 9 a 25) anos. Um aumento significativo foi observado nos valores de p1area, p2area, h2 e dive2. Nenhuma diferença significativa foi encontrada na histerese da córnea, fator de resistência da córnea ou outros parâmetros derivados da forma de onda foi observada em um ano de pós-operatório. Conclusão: Para estimar o efeito do cross-linking corneano acelerado na biomecânica corneana, parâmentros como p1area, p2area, h2 e dive2 são mais sensíveis que histerese da córnea e fator de resistência corneana. Esses resultados podem nos ajudar a descobrir qual método cross-linking corneano é mais eficaz no enrijecimento da córnea.
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Humans , Male , Female , Child , Adolescent , Adult , Young Adult , Keratoconus/surgery , Keratoconus/pathology , Reference Values , Riboflavin/therapeutic use , Vitamin B Complex/therapeutic use , Biomechanical Phenomena , Visual Acuity , Linear Models , Reproducibility of Results , Retrospective Studies , Treatment Outcome , Cornea/surgery , Cornea/pathology , Corneal Topography/instrumentation , Cross-Linking Reagents/therapeutic use , Corneal Pachymetry/methods , Keratoconus/physiopathologyABSTRACT
PURPOSE: To investigate the long-term results (at least 5 years of follow-up) of the mini asymmetric radial keratotomy (MARK) and corneal cross-linking (CXL) combined intervention, also known as the ‘Rome protocol,’ for patients with progressive stage I and II keratoconus and contact lens intolerance. METHODS: This was a retrospective observational case series. Fifteen eyes of 12 patients were evaluated, with a mean follow-up of 6.9 years. To assess the efficacy and stability of the MARK + CXL combined protocol, best spectacle-corrected visual acuity, mean pachymetry, and mean keratometry were recorded preoperatively and at least 1, 3, and 5 years postoperatively. Statistical analysis was performed using the R platform and involved the Wilcoxon signed-rank and Kruskal-Wallis non-parametric tests. RESULTS: Best spectacle-corrected visual acuity improved for all patients, from 0.46 ± 0.69 logarithm of the minimum angle of resolution (20 / 60) to 0.15 ± 0.69 logarithm of the minimum angle of resolution (20 / 30, p = 0.0006), while mean pachymetry increased in 93% of patients, from 442.80 ± 61.02 to 464.50 ± 62.72 µm (p = 0.003). Lastly, mean keratometry improved in 87% of patients after 6.9 years of observation from 48.82 ± 5.00 to 43.25 ± 3.58 diopters (p = 0.008). No intraoperative or postoperative complications were observed. CONCLUSIONS: The MARK + CXL combined protocol was effective in treating keratoconus by halting corneal thinning and bulging. In addition, this procedure significantly improved visual acuity based on long-term follow-up data. Analysis of data from a larger cohort of patients would be useful to support these findings.
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Humans , Cohort Studies , Follow-Up Studies , Keratoconus , Keratotomy, Radial , Postoperative Complications , Retrospective Studies , Visual AcuityABSTRACT
@#AIM: To investigate the efficacy of lamellar keratoplasty(LKP)combined with accelerated(45mW/cm2)corneal cross-linking(A-CXL)on refractory fungal corneal ulcer.<p>METHODS: Eighteen eyes of 18 patients with refractory fungal corneal ulcer were enrolled in the Department of Ophthalmology, First Affiliated Hospital of Jiangxi Medical College from January 2017 to November 2018. The postoperative visual acuity, corneal graft transparency, the incidence and prognosis of complications such as fungal recurrence, graft rejection, secondary glaucoma and complicated cataract were all recorded.<p>RESULTS: All the patients succeeded in avoiding enucleation or evisceration. Postoperatively, 16 eyes(89%)gained one or more lines in uncorrected distance visual acuity 2 eyes(11%)had unchanged in uncorrected distance visual acuity. Three eyes(17%)had a graft rejection. Secondary glaucoma were detected in 2 eyes(11%), and concomitant cataract were found in 3 eyes(17%). Thirteen eyes(72%)had transparent grafts, 4 eyes(22%)had translucent transects, and the remaining one eye(6%)had a turbid graft.<p>CONCLUSION: LK combined with A-CXL may be feasible for refractory fungal corneal ulcer treatment by improving the cure rate.
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@#AIM: To evaluate the visual, refractive and clinical outcomes of non-topography-guided photorefractive keratectomy(PRK)and corneal collagen cross linking(CXL)in eyes with keratoconus.<p>METHODS: Totally 34 cases were evaluated for uncorrected distance visual acuities(UDVA)and corrected distance visual acuities(CDVA), flat and steep keratometry readings, and complications were evaluated at 1mo, 3mo, 6mo and 12mo postoperatively.<p>RESULTS: Thirty-four patients with mean age of 23.3±4.0 years. Statistically significant improvement was shown in UCVA and CDVA, with steadiness of refection for 1y postoperative. <i>T</i>-test showed a significant difference(<i>P</i><0.05)in all means between the preoperative and postoperative values(visual acuity, spherical and cylinder changes), with stability over a 1y follow up. Fourier analysis of postoperative images showed an axis shift perpendicular to the preoperative axis.<p>CONCLUSION: Simultaneous non-topography-guided PRK and CXL is safe and effective surgical alternative for keratoconus, yielding improvement in the UDVA, CDVA, and refractive status. Stabilization was achieved as early as 3mo after surgery, the only advantage of topography-guided over non-topography-guided PRK might be the minimal over correction of sphere and the cylindrical axis shift in some patients as detected by Fourier analysis of postoperative pentacam.
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AIM: To report the long- term clinical outcomes of accelerated trans-epithelial corneal cross-linking ( CXL ) protocols using KXL System ( Avedro, USA ) in the treatment of progressive keratoconus. · METHODS: Totally 52 patients ( 102 eyes ) with progressive keratoconus between December 2014 and February 2017 [ maximum keratometry values ( Kmax) ≤60.0D, minimum corneal thickness(Thk) ≥400m] were treated with an accelerate trans-epithelial CXL protocol (UV-A irradiation intensity 45mW/cm2 with a total fluence of 7. 2J/cm2 ) using KXL system ( Avedro, USA ) in Southwest Hospital. The average follow-up time was 11. 65mo (range: 9-26mo). Uncorrected distance visual acuity ( UDVA) , corrected distance visual acuity ( CDVA) , intra- ocular pressure ( IOP ) , slit-lamp microscope examination, Kmax and average keratometry values ( AveK ) , corneal stromal demarcation line depth and endothelial cell density ( ECD) were evaluated. ·RESULTS:The 52 patients (102 eyes) were included in this research, male 36 (70 eyes) and female 16 (32 eyes), average age was 19. 5±4. 6 years. Preoperative CDVA was 0. 84±0. 89 (LogMAR), postoperative CDVA was 0. 69±0. 72 ( P = 0. 398 ). Preoperative UDVA was 1. 02 ± 0. 62 (LogMAR), postoperative UDVA was 0. 85 ± 0. 59 ( P =0. 154 ). Preoperative IOP was 12. 95 ± 4. 40mmHg, postoperative IOP was 11.92±3. 66mmHg (P=0. 272). No statistical difference (P=0. 552) has been found between preoperative and postoperative ECD. Nevertheless, on the Sirius anterior system ( Sirius, CSO, Itlay) , significant statistical difference (P=0. 017) was confirmed between preoperative Kmax ( 50. 83 ± 3. 48D ) and postoperative Kmax (52. 05±3. 63D). Meanwhile, the postoperative Avek (47.74±2. 51D) was significantly lower (P=0. 041) than the preoperative Avek ( 48. 73 ± 4. 33D ). The average corneal stromal demarcation line depth ( 192 ± 23. 6μm ) was detected by the anterior segment OCT. No statistical difference ( P = 0. 816 ) has been found between preoperative and postoperative Thk. No severe complication was observed in all cases. ·CONCLUSION: Accelerated trans-epithelial CXL was effective in decreasing keratometry values for progressive keratoconus in this research, and the outcomes remained stable during the follow-up time. No endothelium damage or other severe complications were observed in this clinical research. The accelerated trans-epithelial CXL is as effective as the standard CXL.
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Corneal cross-linking with riboflavin is a technique to stabilize or reduce corneal ectasia, in diseases such as keratoconus and post-laser-assisted in situ keratomileusis (LASIK) ectasia. There is an interest by patient as well as clinicians to reduce the overall treatment time. Especially, the introduction of corneal cross-linking in combination with corneal laser surgery demands a shorter treatment time to assure a sufficient patient flow. The principles and techniques of accelerated corneal cross-linking is discussed.
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Corneal Cross-Linking (CXL) is an established surgical procedure for the treatment of corneal disorders such as corneal ectasia and keratoconus. This method of treatment stabilises the corneal structure and increases rigidity, reducing the requirement for corneal transplantation. Since its development, many scientific studies have been conducted to investigate ways of improving the procedure. Biomechanical stability of the cornea after exposure to UV-A light, and the effect of shortening procedure time has been some of the many topics explored.
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Before the discovery of corneal cross-linking (CXL), patients with keratoconus would have had to undergo corneal transplantation, or wear rigid gas permeable lenses (RGPs) that would temporarily flatten the cone, thereby improving the vision. The RGP contact lens (CL) would not however alter the corneal stability and if the keratoconus was progressive, the continued steepening of the cone would occur under the RGP CL. To date, the Siena Eye has been the largest study to investigate long term effects of standard CXL. Three hundred and sixty-three eyes were treated and monitored over 4 years, producing reliable long-term results proving long-term stability of the cornea by halting the progression of keratoconus, and proving the safety of the procedure. Traditionally, CXL requires epithelial removal prior to corneal soakage of a dextran-based 0.1% riboflavin solution, followed by exposure of ultraviolet-A (UV-A) light for 30 min with an intensity of 3 mW/cm2. A series of in vitro investigations on human and porcine corneas examined the best treatment parameters for standard CXL, such as riboflavin concentration, intensity, wavelength of UV-A light, and duration of treatment. Photochemically, CXL is achieved by the generation of chemical bonds within the corneal stroma through localized photopolymerization, strengthening the cornea whilst minimizing exposure to the surrounding structures of the eye. In vitro studies have shown that CXL has an effect on the biomechanical properties of the cornea, with an increased corneal rigidity of approximately 70%. This is a result of the creation of new chemical bonds within the stroma.
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PURPOSE: To report the clinical results of 10 progressive keratoconic eyes in Korean patients treated by corneal cross-linking and compare the progression of keratoconus in the fellow eyes. METHODS: This present retrospective case series was comprised of 10 progressive keratoconic eyes (10 patients) that had corneal cross-linking. Patients were examined before corneal cross-linking as well as 1, 3, 6, 9, and 12 months postoperatively. The main outcome measures were best corrected visual acuity, maximum keratometry, mean keratometry, corneal thickness, corneal astigmatism and endothelial cell count. RESULTS: The best corrected visual acuity (logMAR) improved from 0.60 +/- 0.39 to 0.52 +/- 0.38 at 12 months postoperatively. The maximum keratometry decreased from 62.39 +/- 8.82 D preoperatively to 60.21 +/- 9.21 D at 12 months postoperatively and the mean keratometry decreased from 51.59 +/- 5.86 D to 50.04 +/- 6.21 D at 12 months. In addition, the corneal thickness (at the thinnest area) decreased from 433.60 +/- 44.31 microm to 403.40 +/- 38.95 microm at 12 months. There was no statistically significant difference between the preoperative and 12 months postoperative endothelial cell count (p = 0.731). CONCLUSIONS: This present 1-year follow-up study of Korean keratoconus patients showed corneal cross-linking appeared to be effective in the stabilizing progression of keratoconus and improving best corrective visual acuity and keratometry.