AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this study.First,complete ocul...AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this study.First,complete ocular examinations were performed for all patients,including visual acuity measurement,refraction,and slit-lamp biomicroscopy.Then,all participants underwent corneal imaging by the Oculus Pentacam HR.RESULTS:The mean age of the participants was 32.40±8.52y(15-60y)and 69.5%of them were male.The mean ACA was 38.47°±5.75°(range:14.40°to 56.50°)in the whole sample,38.24°±6.00°in males,and 38.98°±5.11°in females(P=0.447).The mean ACA was significantly different among different groups of cone morphology,as patients with nipple cones showed the lowest mean ACA.Moreover,there were statistically significant differences in the mean ACA among different groups of cone locations,with patients having central cones exhibiting the lowest mean ACA(P<0.001).Anterior and posterior Q values were significantly,directly correlated with ACA(anterior Q:r=0.122,P=0.014,posterior Q:r=0.192,P<0.001).CONCLUSION:This study provides critical insights into the risk factors for ACA narrowing in KCN patients,which is essential for planning intraocular surgeries.Patients with nipple and central cones exhibited the most significant ACA narrowing.Additionally,more negative Q-values are associated with increased ACA narrowing,highlighting the need for targeted diagnostic and therapeutic strategies.展开更多
Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study...Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study aims to identify potential pathogenetic gene mutations in patients with sporadic KC in the Han Chinese population.Methods:Twenty-five patients with primary KC as well as 50 unrelated population matched healthy controls,were included in this study to identify potential pathogenic gene mutations among sporadic KC patients in the Han Chinese population.Sanger sequencing and whole-exome sequencing(WES)were used to analyze mutations in the zinc finger protein 469(ZNF469)gene.Bioinformatics analysis was conducted to explore the potential role of ZNF469 in KC pathogenesis.Results:Five novel heterozygous missense variants were identified in KC patients.Among them,2 compound heterozygous variants,c.8986G>C(p.E2996Q)with c.11765A>C(p.D3922A),and c.4423C>G(p.L1475V)with c.10633G>A(p.G3545R),were determined to be possible pathogenic factors for KC.Conclusion:Mutations in the ZNF469 gene may contribute to the development of KC in the Han Chinese population.These mutation sites may provide valuable information for future genetic screening of KC patients and their families.展开更多
AIM:To investigate the response of the anterior and posterior corneal surface in femtosecond laser-assisted convex stromal lenticule addition keratoplasty(SLAK)combined with cross-linking(CXL)for treating keratoconus ...AIM:To investigate the response of the anterior and posterior corneal surface in femtosecond laser-assisted convex stromal lenticule addition keratoplasty(SLAK)combined with cross-linking(CXL)for treating keratoconus at the first 3mo of follow-up.METHODS:In this prospective observational study,20 eyes of 20 keratoconus patients who underwent SLAK combined with CXL were included.The morphological indices in keratometry and elevation data were recorded from the Sirius at baseline and 1 and 3mo postoperatively.The mean values of maximum keratometry(K_(max)),flat keratometry(K_(1)),and steep keratometry(K_(2))at the central,3-mm,5-mm,and 7-mm areas were measured from the curvature map.The changes in anterior and posterior corneal elevation under the best-fit sphere(BFS)radius at seven points horizontally of the center,3-mm,5-mm,and 7-mm area from the center at both nasal(N)and temporal(T)side were measured from elevation map.RESULTS:For the front corneal curvature,K_(1),and K_(2) at 3-mm,5-mm,and 7-mm of the anterior corneal surface increased significantly 1mo postoperatively(all P<0.05)and remained unchanged until 3mo(P>0.05).For the back corneal curvature,K_(1) and K_(2) along the 3-mm back meridian significantly decreased after month 1(P=0.002,0.077,respectively).Posterior K_(2)-readings along the 5-mm and 7-mm did not change after surgery(P>0.05).Anterior BFS decreased 1mo(P<0.001)postoperatively but remained unchanged until 3mo after SLAK(P>0.05).There was no change in posterior BFS before and after the surgery(P>0.05).Anterior elevation at N5,N3,central,and T5 points and posterior elevation at central and T7 points shifted backward 1mo postoperatively(all P<0.05)and remained stable until 3mo(P>0.05).CONCLUSION:The myopic SLAK combined with CXL is an economical alternative for stabilizing the corneal surface in severe keraoconus.“Pseudoprogression”occurs in the early phase postoperatively,but it is not an indicator of keratoconus progression.展开更多
AIM:To compare simultaneous corneal collagen cross-linking(CXL)with intracorneal ring segment(ICRS)implantation versus successive ICRS followed by CXL and detect the impact of the timing of CXL after ICRS implantation...AIM:To compare simultaneous corneal collagen cross-linking(CXL)with intracorneal ring segment(ICRS)implantation versus successive ICRS followed by CXL and detect the impact of the timing of CXL after ICRS implantation in the successive method.METHODS:This is a retrospective study of the records of three groups of patients.Group 1 of 28 patients were operated on with simultaneous ICRS implantation and CXL,group 2 of 32 patients had ICRS implantation followed by CXL after 1mo,and group 3 of 38 patients had ICRS implantation followed by CXL after 3mo.The three groups had follow-up visits after 6,12,and 24mo.RESULTS:The preoperative data,age,and gender differences among 3 groups revealed no significant differences.The postoperative spherical equivalent and best-corrected visual acuity were improved significantly in all groups compared to the baseline,which were more evident in groups 1 and 2.The differences between preoperative and postoperative mean values of mean of K readings(Km)and maximum K reading(Kmax)at 6mo were 4.66 and 4.1 D in group 1,4.43 and 4.64 D in group 2,but 3.2 and 3.4 D in group 3,respectively.The spherical aberrations and the vertical coma showed significant postoperative changes in all groups,and trefoil showed nonsignificant changes.CONCLUSION:Simultaneous and sequential ICRS implantation and CXL at 1mo has similar Km and Kmax better postoperative changes than when both surgeries were done at three-month intervals.展开更多
AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients ...AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients diagnosed with mild KCN.Objective dry retinoscopy using autorefractometer and subjective refraction measurements were performed.Sphere,cylinder,J0,J45,and spherical equivalent values were compared between the two techniques.RESULTS:The mean age of 68 patients with mild KCN was 21.32±5.03y(12–35y).There were 37(54.4%)males.Objective refraction yielded significantly more myopic sphere(-1.44 D vs-0.57 D),higher cylinder magnitude(-2.24 D vs-1.48 D),and more myopic spherical equivalent(-2.56 D vs-1.31 D)compared to subjective refraction(all P<0.05).The mean differences were-0.87 D for sphere,-0.76 D for cylinder,and-1.25 D for spherical equivalent.No significant differences were found for J0 and J45 values,indicating agreement in astigmatism axis(P>0.05).CONCLUSION:In patients with mild KCN,objective dry retinoscopy overestimates the degree of myopia and astigmatism compared to subjective refraction.The irregular cornea in KCN likely impacts objective measurements.Subjective refraction allows compensation for irregularity,providing a more accurate correction.When determining refractive targets,the tendency of objective methods to overcorrect should be considered.展开更多
AIM:To evaluate the diagnostic ability of topographic and tomographic indices with Pentacam and Sirius as well as biomechanical parameters with Corvis ST for the detection of clinical and subclinical forms of keratoco...AIM:To evaluate the diagnostic ability of topographic and tomographic indices with Pentacam and Sirius as well as biomechanical parameters with Corvis ST for the detection of clinical and subclinical forms of keratoconus(KCN).METHODS:In this prospective diagnostic test study,70 patients with clinical KCN,79 patients with abnormal findings in topography and tomography maps with no evidence on clinical examination(subclinical KCN),and 68 normal control subjects were enrolled.The accuracy of topographic,tomographic,and biomechanical parameters was evaluated using the area under the receiver operating characteristic curve(AUC)and cross-validation analysis.The Delong method was used for comparing AUCs.RESULTS:In distinguishing KCN from normal,all parameters showed statistically significant differences between the two groups(P<0.001).Indices with the perfect diagnostic ability(AUC≥0.999)were Sirius KCN vertex of back(KVb),Pentacam random forest index(PRFI),Pentacam index of height decentration(IHD),and Corvis integrated tomographic/biomechanical index(TBI).In distinguishing subclinical KCN from normal,Sirius symmetry index of back(SIb;AUC=0.908),Pentacam inferior-superior difference(IS)value(AUC=0.862),PRFI(AUC=0.847),and Corvis TBI(AUC=0.820)performed best.There were no significant differences between the highest AUCs within keratoconic groups(De Long,P>0.05).CONCLUSION:In clinical KCN,all topographic,tomographic,and biomechanical indices have acceptable outcomes in terms of sensitivity and specificity.However,in differentiating subclinical forms of KCN from normal corneas,curvature-based parameters(SIb and IS value)followed by integrated indices(PRFI and TBI)are the most powerful tools for early detection of KCN.展开更多
AIMTo evaluate and compare corneal biomechanical findings measured by ocular response analyzer, topographic and pachymetric findings in patients with unilateral keratoconus patients and healthy controls.METHODSThis is...AIMTo evaluate and compare corneal biomechanical findings measured by ocular response analyzer, topographic and pachymetric findings in patients with unilateral keratoconus patients and healthy controls.METHODSThis is an observational, case-control study. Patients with keratoconus in one eye and forme fruste keratoconus in the fellow eye were compared with sex and age matched with controls healthy subjects. All subjects were evaluated with rotating scheimpflug imaging system. The receiver-operating-characteristic curves were analyzed to evaluate the sensitivity and specificity of the parameters.RESULTSTwenty-seven patients with keratoconus in one eye and forme fruste keratoconus in the fellow eye were compared with 40 eyes of 40 normal subjects. Corneal hysteresis (CH) was 8.0±1.7 mm Hg in keratoconus group, 8.3±1.6 mm Hg in forme fruste keratoconus group, and 9.8±1.6 mm Hg in control groups (P=0.54 between keratoconus and forme fruste keratoconus groups, P<0.01 between control group and other groups). Corneal resistance factor (CRF) was 7.1±2.2 mm Hg in keratoconus group, 7.8±1.2 mm Hg in forme fruste keratoconus group and 9.9±1.5 mm Hg in control group (P<0.001 between control group and other groups). Using receiver-operating-characteristic analysis, the area under curve values of the parameters to distinguish forme fruste keratoconus from control subjects were: CH (0.768), CRF (0.866). Best cut-off points were 9.3 mm Hg and 8.8 mm Hg for CH and CRF respectively.CONCLUSIONOcular response analyzer parameters (CH and CRF) are found to be significantly lower in forme fruste keratoconus patients compared to normal control subjects.展开更多
AIM:To evaluate the efficacy of custom-made soft keratoconus(KC)lenses on corneal aberrations and photic phenomena in two different optical zones in patients with KC.METHODS:Sixty eyes of 42 patients with KC were exam...AIM:To evaluate the efficacy of custom-made soft keratoconus(KC)lenses on corneal aberrations and photic phenomena in two different optical zones in patients with KC.METHODS:Sixty eyes of 42 patients with KC were examined at baseline and after fitting HydroCone(Toris K)soft silicone hydrogel lenses.Best spectacle-corrected visual acuity(BSCVA)and contact lens-corrected visual acuity(CLCVA)were recorded.Lower-and higher-order corneal aberrations(LOAs and HOAs)were measured with and without Toris K lenses and compared in central 4.5 mm and 7 mm zones.Mesopic pupil diameter and subjective photic phenomena were also assessed.RESULTS:Mean CLCVA was significantly improved compared to BSCVA(P<0.0001).Corneal curvature and refractive measurements were found to be significantly reduced by the use of Toris K lenses,except for posterior corneal curvature values.In the 4.5 mm central optical zone,all wavefront aberrations decreased significantly after lens fitting(P<0.0001).In contrast,in the 7 mm(peripheral)optical zone,values for HOAs,spherical and residual aberrations,and optical path differences were increased,while LOAs,trefoil,and quadrifoil coefficients were decreased.The rate of photic phenomena was significantly higher in participants with a pupil size>6.00 mm(85.7%).CONCLUSION:Toris K lenses provide good visual results and a significant reduction in central corneal aberrations in patients with KC but could cause an increase in peripheral aberrations.This practical and nonsurgical approach appears to be an effective method for the visual management of KC.展开更多
The aim of the study is to evaluate the safety and effi cacy of trans-epithelial accelerated corneal cross-linking（TE-ACXL） in children with progressive keratoconus.Retrospective,case-series of 23 eyes of 14 childre...The aim of the study is to evaluate the safety and effi cacy of trans-epithelial accelerated corneal cross-linking（TE-ACXL） in children with progressive keratoconus.Retrospective,case-series of 23 eyes of 14 children who underwent TE-ACXL.Evaluations were performed at baseline and 1,3,6,12 and 18 mo postoperatively.Mean follow-up time of 23.82±3.15 mo and mean age was 13.7±1.4 y（range 11 to 16 y）.Mean preoperative uncorrected distance visual acuity changed from 0.92±0.45 log MAR（20/160） to 0.71±0.40 log MAR（20/100）（P=0.001）.Mean keratometry（Km） changed from 53.87± 6.03 to 53.00±5.81（P=0.001）.Pachymetry did not have significant changes at last follow-up（P=0.30）.The mean preoperative sphere was-5.58±2.48 and-4.89±4.66 D（P=0.11） at last follow-up;refractive cylinder from-5.58±2.48 to-5.02±2.23（P=0.046）.In conclusion,tomographic and refractive stability are shown in over 91% of eyes with pediatric progressive keratoconus who underwent TE-ACXL.展开更多
· AIM: To identify topographic characteristics of keratoconus in a Jordanian sample.· METHODS: This study characterized 210 corneas affected with keratoconus presenting to Jordan University Hospital. Patient...· AIM: To identify topographic characteristics of keratoconus in a Jordanian sample.· METHODS: This study characterized 210 corneas affected with keratoconus presenting to Jordan University Hospital. Patients were diagnosed based on clinical examinations and Pentacam imaging. Eyes of males(n =101) were of a similar proportion to females(n =109). All of the 111 patients were affected bilaterally.Ages ranged between 13 and 44 y with a mean age of25.2y.· RESULTS: Results revealed significant differences between males and females at the level of the flat curvature power, basement membrane thickness and size of the anterior chamber. Eyes were arranged in three groups based on severity levels: mild, moderate and severe determined by the mean curvature power(Km).Results show that the flat(K1) and steep(K2) curvature powers, corneal asphericity coefficient(QV), thinnest point, pachy apex and basement membrane thickness are significantly different among the three groups, but not the corneal and anterior chamber volumes.Morphological analyses, based on sagittal maps, show no differences in keratometric values between eyes with different sagittal patterns except for the vertical location of the pachy apex relative to the pupil center and the thinnest point. Eyes with the island front elevation map are significantly more affected than eyes with the U shape and the ridge pattern.· CONCLUSION: All keratometric values measured except for corneal and anterior chamber volumes vary significantly with disease severity. The vertical pachy apex location correlates well with severity levels while the horizontal location seems to have no effect. Ourstudy also indicates that front elevation maps may be a better predictor of the severity of keratoconus than sagittal maps.展开更多
Keratoconus is a non-inflammatory disorder which is gradual in development;corneal thinning and ectatic protrusion characterizes it. Keratoconus prevalence varies between different regions depending on several factors...Keratoconus is a non-inflammatory disorder which is gradual in development;corneal thinning and ectatic protrusion characterizes it. Keratoconus prevalence varies between different regions depending on several factors that affecting its prevalence. There are risk factors for developing keratoconus such as demographic and environmental factors. It was suggested that eye rubbing was associated with the development of keratoconus. The main aim of this review was to summarize the literature data about keratoconus and to identify the role of eyerubbing in the aetiology of the disease. A number of 24 articles was reviewed through the Pub Med, Google Scholar and Research Gates. There are many keywords used such as keratoconus, aetiology of keratoconus, eye rubbing, keratoconus prevalence, keratoconus and eye rubbing correlation. We concluded that eye rubbing causes the thinning of keratocyte, and the degree of effect of eye rubbing depends on the period and force of performing eye rubbing. It is recommended to avoid eye rubbing to prevent keratoconus, this can be achieved by avoiding itching and treating dryness of the eye and avoiding wearing eye lenses.展开更多
Objective: To compare postoperative outcomes of full-bed deep anterior lamellar keratoplasty (DALK) with penetrating keratoplasty (PK) in treating keratoconus. Methods: Seventy-five eyes of 64 patients who received fu...Objective: To compare postoperative outcomes of full-bed deep anterior lamellar keratoplasty (DALK) with penetrating keratoplasty (PK) in treating keratoconus. Methods: Seventy-five eyes of 64 patients who received full-bed DALK and 52 eyes of 51 patients who received PK between June 2000 and August 2010 were included in this retrospective study. Full-bed DALK was performed using Yao's hooking-detaching technique. PK was performed using a standard technique. Intraoperative and postoperative complications, visual acuity, rejection, graft survival, endothelial cell density, corneal sensation recovery, and re-innervation were compared between the two groups. Results: A best correct visual acuity of 0.5 or better was achieved in 90.7% of eyes after full-bed DALK and in 92.3% of eyes after PK (P=0.75). By the fifth postoperative year, graft endothelial cell loss reached 34.6% in the PK group vs. 13.9% in the full-bed DALK group (P<0.001). There were no statistical differences in corneal sensitivity recovery or corneal re-innervation between the groups (P>0.05). Intraoperative microperforation occurred in seven out of 75 (9.3%) eyes with a temporally postoperative double anterior chamber in two eyes in the full-bed DALK group. Postoperative complications in the PK vs. the full-bed DALK groups respectively were: rejection (7.7% vs. 0%, P=0.015), high intraocular pressure (IOP) (46.2% vs. 1.3%, P<0.001), secondary glaucoma (9.6% vs. 0%, P=0.006), complicated cataract (19.2% vs. 0%, P<0.001), and wound dehiscence (9.6% vs. 0%, P=0.006). Conclusions: Both full-bed DALK and PK can offer long-term satisfactory visual outcomes for keratoconus. Graft rejection, secondary glaucoma, complicated cataracts, and constant endothelial cell loss were observed in eyes only after PK.展开更多
Keratoconus is a condition characterized by biomechanical instability of the cornea, presenting in a progressive, asymmetric and bilateral way. Corneal collagen crosslinking(CXL) with riboflavin and Ultraviolet-A(UVA)...Keratoconus is a condition characterized by biomechanical instability of the cornea, presenting in a progressive, asymmetric and bilateral way. Corneal collagen crosslinking(CXL) with riboflavin and Ultraviolet-A(UVA) is a new technique of corneal tissue strengthening that combines the use of riboflavin as a photo sensitizer and UVA irradiation. Studies showed that CXL was effective in halting the progression of keratoconus over a period of up to four years. The published studies also revealed a reduction of max K readings by more than 2 D, while the postoperative spherical equivalent(SEQ) was reduced by an average of more than 1 D and refractive cylinder decreased by about1 D. The major indication for the use of CXL is to inhibit the progression of corneal ecstasies, such as keratoconus and pellucid marginal degeneration. CXL may also be effective in the treatment and prophylaxis of iatrogenic keratectasia, resulting from excessively aggressive photo ablation. This treatment has been used to treat infectious corneal ulcers with apparent favorable results. Most recent studies demonstrate the beneficial impact of CXL for iatrogenic ecstasies, pellucid marginal degeneration, infectious keratitis, bullous keratopathy and ulcerative keratitis. Several long-term and short-term complications of CXL have been studied and documented. The possibility of a secondary infection after the procedure exists because the patient is subject to epithelial debridement and the application of a soft contact lens. Formation of temporary corneal haze,permanent scars, endothelial damage, treatment failure,sterile infiltrates, bullous keratopathy and herpes reactivation are the other reported complications of this procedure.展开更多
AIM: To quantify corneal ultrastructure using laser scanning in vivo confocal microscopy(IVCM) in patients with keratoconus and control subjects. METHODS: Unscarred corneas of 78 keratoconic subjects without a history...AIM: To quantify corneal ultrastructure using laser scanning in vivo confocal microscopy(IVCM) in patients with keratoconus and control subjects. METHODS: Unscarred corneas of 78 keratoconic subjects without a history of contact lens use and 36age-matched control subjects were evaluated with slit-lamp examination(SLE), corneal topography and laser scanning IVCM. One eye was randomly chosen for analysis. Anterior and posterior stromal keratocyte,endothelial cell and basal epithelial cell densities and sub-basal nerve structure were evaluated.RESULTS: IVCM qualitatively demonstrated enlarged basal epithelial cells, structural changes in sub-basal and stromal nerve fibers, abnormal stromal keratocytes and keratocyte nuclei, and pleomorphism and enlargement of endothelial cells. Compared with control subjects, significant reductions in basal epithelial cell density( 5817 ± 306 cells / mm2 vs 4802 ±508 cells/mm2,P 【 0. 001), anterior stromal keratocyte density(800 ±111 cells/mm2 vs 555 ±115 cells/mm2, P 【0.001),posterior stromal keratocyte density(333±34 cells/mm2vs270 ±47 cells/mm2, P 【0.001), endothelial cell density(2875 ±223 cells/mm2 vs 2686 ±265 cells/mm2, P 【0.001),sub-basal nerve fiber density(31.2 ±8.4 nerves/mm2vs18.1 ±9.2 nerves/mm2, P 【0.001), sub-basal nerve fiber length(21.4±3.4 mm/mm2 vs 16.1±5.1 mm/mm2, P 【0.001),and sub-basal nerve branch density(median 50.0(first quartile 31.2- third quartile 68.7) nerve branches/mm2 vs median 25.0(first quartile 6.2- third quartile 45.3) nerve branches/mm2, P 【0.001) were observed in patients with keratoconus.CONCLUSION: Significant microstructural abnormalities were identified in all corneal layers in the eyes of subjects with keratoconus using IVCM. This non-invasive in vivo technique provides an important means to define and follow progress of microstructural changes in patients with keratoconus.展开更多
·AIM: To describe the initial outcomes and safety of femtosecond laser-assisted deep anterior lamellar keratoplasty(DALK) for keratoconus and post-LASIK keratectasia.·METHODS: In this non-comparative case se...·AIM: To describe the initial outcomes and safety of femtosecond laser-assisted deep anterior lamellar keratoplasty(DALK) for keratoconus and post-LASIK keratectasia.·METHODS: In this non-comparative case series, 10 eyes of 9 patients underwent DALK procedures with a femtosecond laser(Carl Zeiss Meditec AG, Jena,Germany). Of the 9 patients, 7 had keratoconus and 2had post-LASIK keratectasia. A 500 kHz VisuMax femtosecond laser was used to perform corneal cuts on both donor and recipient corneas. The outcome measures were the uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA), corneal thickness,astigmatism, endothelial density count(EDC), and corneal power.·RESULTS: All eyes were successfully treated. Early postoperative evaluation showed a clear graft in all cases. Intraoperative complications included one case of a small Descemet’s membrane perforation.Postoperatively, there was one case of stromal rejection,one of loosened sutures, and one of wound dehiscence.A normal corneal pattern topography and transparency were restored, UCVA and BCVA improved significantly,and astigmatism improved slightly. There was no statistically significant decrease in EDC.· CONCLUSION: Our early results indicate that femtosecond laser-assisted deep anterior lamellar keratoplasty could improve UCVA and BCVA in patients with anterior corneal pathology. This approach shows promise as a safe and effective surgical choice in the treatment of keratoconus and post-LASIK keratectasia.展开更多
AIMTo determine the impact of rigid gas permeable (RGP) and silicone-hydrogel keratoconus lenses on the quality of life (QoL) in keratoconus (KCN) patients using the self-reported results from the Contact Lens Impact ...AIMTo determine the impact of rigid gas permeable (RGP) and silicone-hydrogel keratoconus lenses on the quality of life (QoL) in keratoconus (KCN) patients using the self-reported results from the Contact Lens Impact on Quality of Life (CLIQ) Questionnaire.METHODSFrom January 2013 to April 2013, 27 consecutive KCN patients who wore RGP contact lenses (conflexair100 UV KE Zeiss-Wöhlk) or soft silicone-hydrogel contact lenses (SHCLs) for KCN (KeraSoft IC- Bausch&Lomb or Hydrocone Toris K-Swiss lens) completed the CLIQ questionnaire.RESULTSThe mean age of 27 patients was 29.6±8.0y. Fifteen patients were RGP user. The groups were comparable with respect to the mean patient age, sex, and mean K values (P=0.1, P=0.8 and P=0.1, respectively). The mean CLIQperson measure was 42.8±5.5 in RGP group and 39.6±5.5 in SHCLs for KCN group (P=0.06). CLIQperson measure was positively correlated with steep K value (r=0.301, P=0.04). When eyes were stratified by visual acuity with contact lenses, the mean CLIQperson measure was 42.01±5.6 in eyes with a visual acuity of 20/20-20/25 (n=44) and 38.4±5.26 in eyes with a visual acuity of 20/32 or less (n=10; P=0.097).CONCLUSIONRGP lenses and SHCLs for KCN have similar impact on QoL.展开更多
AIM： To evaluate the corneal cell morphology of new keratoconus patients wearing two different types of rigid gas-permeable（RGP） contact lenses for 1y.METHODS： Thirty nine eyes of 39 new keratoconus patients were ...AIM： To evaluate the corneal cell morphology of new keratoconus patients wearing two different types of rigid gas-permeable（RGP） contact lenses for 1y.METHODS： Thirty nine eyes of 39 new keratoconus patients were selected and randomly fitted with two types of RGP contact lenses.Group 1 had 21 eyes with regular rigid gas-permeable（RRGP） contact lens and rest 18 eyes were in group 2 with specially designed rigid gas-permeable（SRGP） contact lens.Corneal cell morphology was evaluated using a slit scanning confocal microscope at no-lens wear and after 1y of contact lens wearing.RESULTS： After 1y of contact lens wearing in group 1,the mean anterior and posterior stromal keratocyte density were significantly less（P=0.006 and P=0.001,respectively） compared to no-lens wear.The mean cell area of anterior and posterior stromal keratocyte were also significantly different（P=0.005 and P=0.001） from no-lens wear.The anterior and posterior stromal haze increased by 18.74% and 23.81%,respectively after 1y of contact lens wearing.Whereas in group 2,statistically significant changes were observed only in cell density ＆ area of anterior stroma（P=0.001 and P=0.001,respectively） after 1y.While,level of anterior and posterior stromal haze increased by 16.67% and 11.11% after 1y of contact lens wearing.Polymegathism and pleomorphism also increased after 1y of contact lens wearing in both the contact lens groups.CONCLUSION： Confocal microscopy observation shows the significant alterations in corneal cell morphology of keratoconic corneas wearing contact lenses especially in group 1.The type of contact lens must be carefully selected to minimize changes in corneal cell morphology.展开更多
AIM: To demonstrate the effects of two different types of allergic conjunctivitis on severity of keratoconus (KC). ·METHODS: We retrospectively reviewed the medical records of 171 KC patients referred between Jun...AIM: To demonstrate the effects of two different types of allergic conjunctivitis on severity of keratoconus (KC). ·METHODS: We retrospectively reviewed the medical records of 171 KC patients referred between June 2010 and June 2011. The KC patients were divided into 3 groups as KC (group A), KC with vernal keratoconjunctivitis (VKC) (group B) and KC with allergic conjunctivitis (AC) (group C). Main outcome measures were demographic and ocular clinical features including age at presentation, gender, spherical equivalent (SE), best spectacle corrected visual acuity (BCVA), mean keratometric measurement (Km), central corneal thickness (CCT), and intraocular pressure (IOP). Groups were compared in term of study variables. · RESULTS: The median age at presentation was significantly lower in group B (P 【0.001). According to the median SE (P =0.003), BCVA(P =0.022), Km(P 【0.001), CCT (P =0.015) and Amsler-Krumeich classification (P 【 0.001), KC was more severe in group B. There was no significant difference in terms of IOP and corrected IOP among the groups (P =0.44), however there were 4 patients who had increased corrected IOP developed after topical corticosteroid use in group B. The differences among the groups persisted even after controlling for age and gender. · CONCLUSION: Our findings demonstrated a more severe KC in VKC patients despite their younger age which suggests evaluation of VKC patients as a separate group in keratoconus disease.展开更多
The prevalence of keratoconus is 1/2000 in the general population and is high in adolescents.Keratoconus is a progressive disease,which has a great impact on patients’quality of life and mental health.It can be manag...The prevalence of keratoconus is 1/2000 in the general population and is high in adolescents.Keratoconus is a progressive disease,which has a great impact on patients’quality of life and mental health.It can be managed by surgical and non-surgical means,rigid gas permeable(RGP)contact lens as its main non-surgical method is widely used in clinic.The efficacy of wearing RGP contact lens has been confirmed to some extent,but some studies have found that wearing RGP contact lens has adverse effects,which may promote disease progression.In this paper,the advantages and disadvantages of RGP contact lens in controlling keratoconus were reviewed to provide more suggestions and references for the clinical application of RGP contact lens.展开更多
AIM:To investigate the expression of visual system homeobox 1(VSX1)and myofibroblast marker alpha smooth muscle actin(α-SMA)in keratoconus(KC).METHODS:Thirty corneal tissue were collected from KC patients after corne...AIM:To investigate the expression of visual system homeobox 1(VSX1)and myofibroblast marker alpha smooth muscle actin(α-SMA)in keratoconus(KC).METHODS:Thirty corneal tissue were collected from KC patients after corneal transplantation and 15 normal donor corneas were obtained.All corneal tissues divided into 4 parts for different detections.Scanning electron microscopy was used to observe the ultrastructure of the specimens.VSX1 andα-SMA localization in cornea tissues was detected using immunofluorescence histochemistry.Reverse transcription-quantitative polymerase chain reaction(RT-qPCR)and Western blot were performed to analyze the expression level of VSX1 andα-SMA.RESULTS:Compared to normal cornea tissue,the collagen fibers in KC stroma were distortional and attenuated and keratocytes were abnormally changed.VSX1 andα-SMA located in the corneal stroma.The mRNA and protein expression level of VSX1 in KC were about 3 times as high as that of normal tissue(P<0.001).α-SMA was hardly expressed in the normal corneas,however,its expression in the KC was about 1.5 times higher than that of the normal corneas(P<0.0001).CONCLUSION:Compared with normal corneal the expression of VSX1 andα-SMA in KC both increased.VSX1 is related to the activation of keratocytes and involved in the pathogenesis of keratoconus.展开更多
基金Supported by Iranian University of Medical Sciences(code:IR.IUMS.REC.1401.371).
文摘AIM:To identify topographic determinants of the anterior chamber angle(ACA)in patients with keratoconus(KCN).METHODS:Four hundred and ten eyes of 294 patients with KCN were recruited for this study.First,complete ocular examinations were performed for all patients,including visual acuity measurement,refraction,and slit-lamp biomicroscopy.Then,all participants underwent corneal imaging by the Oculus Pentacam HR.RESULTS:The mean age of the participants was 32.40±8.52y(15-60y)and 69.5%of them were male.The mean ACA was 38.47°±5.75°(range:14.40°to 56.50°)in the whole sample,38.24°±6.00°in males,and 38.98°±5.11°in females(P=0.447).The mean ACA was significantly different among different groups of cone morphology,as patients with nipple cones showed the lowest mean ACA.Moreover,there were statistically significant differences in the mean ACA among different groups of cone locations,with patients having central cones exhibiting the lowest mean ACA(P<0.001).Anterior and posterior Q values were significantly,directly correlated with ACA(anterior Q:r=0.122,P=0.014,posterior Q:r=0.192,P<0.001).CONCLUSION:This study provides critical insights into the risk factors for ACA narrowing in KCN patients,which is essential for planning intraocular surgeries.Patients with nipple and central cones exhibited the most significant ACA narrowing.Additionally,more negative Q-values are associated with increased ACA narrowing,highlighting the need for targeted diagnostic and therapeutic strategies.
基金supported by the National Natural Science Foundation(82271057)the Natural Science Foundation of Hunan Province(2023JJ30818),China。
文摘Objective:Keratoconus(KC)is a progressive corneal ectasia disorder,arising from a myriad of causes including genetic predispositions,environmental factors,biomechanical influences,and inflammatory reactions.This study aims to identify potential pathogenetic gene mutations in patients with sporadic KC in the Han Chinese population.Methods:Twenty-five patients with primary KC as well as 50 unrelated population matched healthy controls,were included in this study to identify potential pathogenic gene mutations among sporadic KC patients in the Han Chinese population.Sanger sequencing and whole-exome sequencing(WES)were used to analyze mutations in the zinc finger protein 469(ZNF469)gene.Bioinformatics analysis was conducted to explore the potential role of ZNF469 in KC pathogenesis.Results:Five novel heterozygous missense variants were identified in KC patients.Among them,2 compound heterozygous variants,c.8986G>C(p.E2996Q)with c.11765A>C(p.D3922A),and c.4423C>G(p.L1475V)with c.10633G>A(p.G3545R),were determined to be possible pathogenic factors for KC.Conclusion:Mutations in the ZNF469 gene may contribute to the development of KC in the Han Chinese population.These mutation sites may provide valuable information for future genetic screening of KC patients and their families.
基金Supported by the Social Development Grant of Shaanxi Province(No.2022SF-404)the Science and Technology Program of Xi’an,China(No.23YXYJ0010,No.23YXYJ0037)+1 种基金the Research Project of Xi’an Health Commission(No.2024ms05)the Technology Innovation Supporting Program of Shaanxi(No.2024RS-CXTD-11).
文摘AIM:To investigate the response of the anterior and posterior corneal surface in femtosecond laser-assisted convex stromal lenticule addition keratoplasty(SLAK)combined with cross-linking(CXL)for treating keratoconus at the first 3mo of follow-up.METHODS:In this prospective observational study,20 eyes of 20 keratoconus patients who underwent SLAK combined with CXL were included.The morphological indices in keratometry and elevation data were recorded from the Sirius at baseline and 1 and 3mo postoperatively.The mean values of maximum keratometry(K_(max)),flat keratometry(K_(1)),and steep keratometry(K_(2))at the central,3-mm,5-mm,and 7-mm areas were measured from the curvature map.The changes in anterior and posterior corneal elevation under the best-fit sphere(BFS)radius at seven points horizontally of the center,3-mm,5-mm,and 7-mm area from the center at both nasal(N)and temporal(T)side were measured from elevation map.RESULTS:For the front corneal curvature,K_(1),and K_(2) at 3-mm,5-mm,and 7-mm of the anterior corneal surface increased significantly 1mo postoperatively(all P<0.05)and remained unchanged until 3mo(P>0.05).For the back corneal curvature,K_(1) and K_(2) along the 3-mm back meridian significantly decreased after month 1(P=0.002,0.077,respectively).Posterior K_(2)-readings along the 5-mm and 7-mm did not change after surgery(P>0.05).Anterior BFS decreased 1mo(P<0.001)postoperatively but remained unchanged until 3mo after SLAK(P>0.05).There was no change in posterior BFS before and after the surgery(P>0.05).Anterior elevation at N5,N3,central,and T5 points and posterior elevation at central and T7 points shifted backward 1mo postoperatively(all P<0.05)and remained stable until 3mo(P>0.05).CONCLUSION:The myopic SLAK combined with CXL is an economical alternative for stabilizing the corneal surface in severe keraoconus.“Pseudoprogression”occurs in the early phase postoperatively,but it is not an indicator of keratoconus progression.
文摘AIM:To compare simultaneous corneal collagen cross-linking(CXL)with intracorneal ring segment(ICRS)implantation versus successive ICRS followed by CXL and detect the impact of the timing of CXL after ICRS implantation in the successive method.METHODS:This is a retrospective study of the records of three groups of patients.Group 1 of 28 patients were operated on with simultaneous ICRS implantation and CXL,group 2 of 32 patients had ICRS implantation followed by CXL after 1mo,and group 3 of 38 patients had ICRS implantation followed by CXL after 3mo.The three groups had follow-up visits after 6,12,and 24mo.RESULTS:The preoperative data,age,and gender differences among 3 groups revealed no significant differences.The postoperative spherical equivalent and best-corrected visual acuity were improved significantly in all groups compared to the baseline,which were more evident in groups 1 and 2.The differences between preoperative and postoperative mean values of mean of K readings(Km)and maximum K reading(Kmax)at 6mo were 4.66 and 4.1 D in group 1,4.43 and 4.64 D in group 2,but 3.2 and 3.4 D in group 3,respectively.The spherical aberrations and the vertical coma showed significant postoperative changes in all groups,and trefoil showed nonsignificant changes.CONCLUSION:Simultaneous and sequential ICRS implantation and CXL at 1mo has similar Km and Kmax better postoperative changes than when both surgeries were done at three-month intervals.
文摘AIM:To compare objective dry retinoscopy and subjective refraction measurements in patients with mild keratoconus(KCN)and quantify any differences.METHODS:This cross-sectional study was done on 68 eyes of 68 patients diagnosed with mild KCN.Objective dry retinoscopy using autorefractometer and subjective refraction measurements were performed.Sphere,cylinder,J0,J45,and spherical equivalent values were compared between the two techniques.RESULTS:The mean age of 68 patients with mild KCN was 21.32±5.03y(12–35y).There were 37(54.4%)males.Objective refraction yielded significantly more myopic sphere(-1.44 D vs-0.57 D),higher cylinder magnitude(-2.24 D vs-1.48 D),and more myopic spherical equivalent(-2.56 D vs-1.31 D)compared to subjective refraction(all P<0.05).The mean differences were-0.87 D for sphere,-0.76 D for cylinder,and-1.25 D for spherical equivalent.No significant differences were found for J0 and J45 values,indicating agreement in astigmatism axis(P>0.05).CONCLUSION:In patients with mild KCN,objective dry retinoscopy overestimates the degree of myopia and astigmatism compared to subjective refraction.The irregular cornea in KCN likely impacts objective measurements.Subjective refraction allows compensation for irregularity,providing a more accurate correction.When determining refractive targets,the tendency of objective methods to overcorrect should be considered.
文摘AIM:To evaluate the diagnostic ability of topographic and tomographic indices with Pentacam and Sirius as well as biomechanical parameters with Corvis ST for the detection of clinical and subclinical forms of keratoconus(KCN).METHODS:In this prospective diagnostic test study,70 patients with clinical KCN,79 patients with abnormal findings in topography and tomography maps with no evidence on clinical examination(subclinical KCN),and 68 normal control subjects were enrolled.The accuracy of topographic,tomographic,and biomechanical parameters was evaluated using the area under the receiver operating characteristic curve(AUC)and cross-validation analysis.The Delong method was used for comparing AUCs.RESULTS:In distinguishing KCN from normal,all parameters showed statistically significant differences between the two groups(P<0.001).Indices with the perfect diagnostic ability(AUC≥0.999)were Sirius KCN vertex of back(KVb),Pentacam random forest index(PRFI),Pentacam index of height decentration(IHD),and Corvis integrated tomographic/biomechanical index(TBI).In distinguishing subclinical KCN from normal,Sirius symmetry index of back(SIb;AUC=0.908),Pentacam inferior-superior difference(IS)value(AUC=0.862),PRFI(AUC=0.847),and Corvis TBI(AUC=0.820)performed best.There were no significant differences between the highest AUCs within keratoconic groups(De Long,P>0.05).CONCLUSION:In clinical KCN,all topographic,tomographic,and biomechanical indices have acceptable outcomes in terms of sensitivity and specificity.However,in differentiating subclinical forms of KCN from normal corneas,curvature-based parameters(SIb and IS value)followed by integrated indices(PRFI and TBI)are the most powerful tools for early detection of KCN.
文摘AIMTo evaluate and compare corneal biomechanical findings measured by ocular response analyzer, topographic and pachymetric findings in patients with unilateral keratoconus patients and healthy controls.METHODSThis is an observational, case-control study. Patients with keratoconus in one eye and forme fruste keratoconus in the fellow eye were compared with sex and age matched with controls healthy subjects. All subjects were evaluated with rotating scheimpflug imaging system. The receiver-operating-characteristic curves were analyzed to evaluate the sensitivity and specificity of the parameters.RESULTSTwenty-seven patients with keratoconus in one eye and forme fruste keratoconus in the fellow eye were compared with 40 eyes of 40 normal subjects. Corneal hysteresis (CH) was 8.0±1.7 mm Hg in keratoconus group, 8.3±1.6 mm Hg in forme fruste keratoconus group, and 9.8±1.6 mm Hg in control groups (P=0.54 between keratoconus and forme fruste keratoconus groups, P<0.01 between control group and other groups). Corneal resistance factor (CRF) was 7.1±2.2 mm Hg in keratoconus group, 7.8±1.2 mm Hg in forme fruste keratoconus group and 9.9±1.5 mm Hg in control group (P<0.001 between control group and other groups). Using receiver-operating-characteristic analysis, the area under curve values of the parameters to distinguish forme fruste keratoconus from control subjects were: CH (0.768), CRF (0.866). Best cut-off points were 9.3 mm Hg and 8.8 mm Hg for CH and CRF respectively.CONCLUSIONOcular response analyzer parameters (CH and CRF) are found to be significantly lower in forme fruste keratoconus patients compared to normal control subjects.
文摘AIM:To evaluate the efficacy of custom-made soft keratoconus(KC)lenses on corneal aberrations and photic phenomena in two different optical zones in patients with KC.METHODS:Sixty eyes of 42 patients with KC were examined at baseline and after fitting HydroCone(Toris K)soft silicone hydrogel lenses.Best spectacle-corrected visual acuity(BSCVA)and contact lens-corrected visual acuity(CLCVA)were recorded.Lower-and higher-order corneal aberrations(LOAs and HOAs)were measured with and without Toris K lenses and compared in central 4.5 mm and 7 mm zones.Mesopic pupil diameter and subjective photic phenomena were also assessed.RESULTS:Mean CLCVA was significantly improved compared to BSCVA(P<0.0001).Corneal curvature and refractive measurements were found to be significantly reduced by the use of Toris K lenses,except for posterior corneal curvature values.In the 4.5 mm central optical zone,all wavefront aberrations decreased significantly after lens fitting(P<0.0001).In contrast,in the 7 mm(peripheral)optical zone,values for HOAs,spherical and residual aberrations,and optical path differences were increased,while LOAs,trefoil,and quadrifoil coefficients were decreased.The rate of photic phenomena was significantly higher in participants with a pupil size>6.00 mm(85.7%).CONCLUSION:Toris K lenses provide good visual results and a significant reduction in central corneal aberrations in patients with KC but could cause an increase in peripheral aberrations.This practical and nonsurgical approach appears to be an effective method for the visual management of KC.
文摘The aim of the study is to evaluate the safety and effi cacy of trans-epithelial accelerated corneal cross-linking（TE-ACXL） in children with progressive keratoconus.Retrospective,case-series of 23 eyes of 14 children who underwent TE-ACXL.Evaluations were performed at baseline and 1,3,6,12 and 18 mo postoperatively.Mean follow-up time of 23.82±3.15 mo and mean age was 13.7±1.4 y（range 11 to 16 y）.Mean preoperative uncorrected distance visual acuity changed from 0.92±0.45 log MAR（20/160） to 0.71±0.40 log MAR（20/100）（P=0.001）.Mean keratometry（Km） changed from 53.87± 6.03 to 53.00±5.81（P=0.001）.Pachymetry did not have significant changes at last follow-up（P=0.30）.The mean preoperative sphere was-5.58±2.48 and-4.89±4.66 D（P=0.11） at last follow-up;refractive cylinder from-5.58±2.48 to-5.02±2.23（P=0.046）.In conclusion,tomographic and refractive stability are shown in over 91% of eyes with pediatric progressive keratoconus who underwent TE-ACXL.
文摘· AIM: To identify topographic characteristics of keratoconus in a Jordanian sample.· METHODS: This study characterized 210 corneas affected with keratoconus presenting to Jordan University Hospital. Patients were diagnosed based on clinical examinations and Pentacam imaging. Eyes of males(n =101) were of a similar proportion to females(n =109). All of the 111 patients were affected bilaterally.Ages ranged between 13 and 44 y with a mean age of25.2y.· RESULTS: Results revealed significant differences between males and females at the level of the flat curvature power, basement membrane thickness and size of the anterior chamber. Eyes were arranged in three groups based on severity levels: mild, moderate and severe determined by the mean curvature power(Km).Results show that the flat(K1) and steep(K2) curvature powers, corneal asphericity coefficient(QV), thinnest point, pachy apex and basement membrane thickness are significantly different among the three groups, but not the corneal and anterior chamber volumes.Morphological analyses, based on sagittal maps, show no differences in keratometric values between eyes with different sagittal patterns except for the vertical location of the pachy apex relative to the pupil center and the thinnest point. Eyes with the island front elevation map are significantly more affected than eyes with the U shape and the ridge pattern.· CONCLUSION: All keratometric values measured except for corneal and anterior chamber volumes vary significantly with disease severity. The vertical pachy apex location correlates well with severity levels while the horizontal location seems to have no effect. Ourstudy also indicates that front elevation maps may be a better predictor of the severity of keratoconus than sagittal maps.
文摘Keratoconus is a non-inflammatory disorder which is gradual in development;corneal thinning and ectatic protrusion characterizes it. Keratoconus prevalence varies between different regions depending on several factors that affecting its prevalence. There are risk factors for developing keratoconus such as demographic and environmental factors. It was suggested that eye rubbing was associated with the development of keratoconus. The main aim of this review was to summarize the literature data about keratoconus and to identify the role of eyerubbing in the aetiology of the disease. A number of 24 articles was reviewed through the Pub Med, Google Scholar and Research Gates. There are many keywords used such as keratoconus, aetiology of keratoconus, eye rubbing, keratoconus prevalence, keratoconus and eye rubbing correlation. We concluded that eye rubbing causes the thinning of keratocyte, and the degree of effect of eye rubbing depends on the period and force of performing eye rubbing. It is recommended to avoid eye rubbing to prevent keratoconus, this can be achieved by avoiding itching and treating dryness of the eye and avoiding wearing eye lenses.
基金Project (No. 2011C13029-2) supported by the Major Program for Science and Technology Research of Zhejiang Province, China
文摘Objective: To compare postoperative outcomes of full-bed deep anterior lamellar keratoplasty (DALK) with penetrating keratoplasty (PK) in treating keratoconus. Methods: Seventy-five eyes of 64 patients who received full-bed DALK and 52 eyes of 51 patients who received PK between June 2000 and August 2010 were included in this retrospective study. Full-bed DALK was performed using Yao's hooking-detaching technique. PK was performed using a standard technique. Intraoperative and postoperative complications, visual acuity, rejection, graft survival, endothelial cell density, corneal sensation recovery, and re-innervation were compared between the two groups. Results: A best correct visual acuity of 0.5 or better was achieved in 90.7% of eyes after full-bed DALK and in 92.3% of eyes after PK (P=0.75). By the fifth postoperative year, graft endothelial cell loss reached 34.6% in the PK group vs. 13.9% in the full-bed DALK group (P<0.001). There were no statistical differences in corneal sensitivity recovery or corneal re-innervation between the groups (P>0.05). Intraoperative microperforation occurred in seven out of 75 (9.3%) eyes with a temporally postoperative double anterior chamber in two eyes in the full-bed DALK group. Postoperative complications in the PK vs. the full-bed DALK groups respectively were: rejection (7.7% vs. 0%, P=0.015), high intraocular pressure (IOP) (46.2% vs. 1.3%, P<0.001), secondary glaucoma (9.6% vs. 0%, P=0.006), complicated cataract (19.2% vs. 0%, P<0.001), and wound dehiscence (9.6% vs. 0%, P=0.006). Conclusions: Both full-bed DALK and PK can offer long-term satisfactory visual outcomes for keratoconus. Graft rejection, secondary glaucoma, complicated cataracts, and constant endothelial cell loss were observed in eyes only after PK.
基金Supported by Jiangsu Province's Key Provincial Talents Program(RC2011104)
文摘Keratoconus is a condition characterized by biomechanical instability of the cornea, presenting in a progressive, asymmetric and bilateral way. Corneal collagen crosslinking(CXL) with riboflavin and Ultraviolet-A(UVA) is a new technique of corneal tissue strengthening that combines the use of riboflavin as a photo sensitizer and UVA irradiation. Studies showed that CXL was effective in halting the progression of keratoconus over a period of up to four years. The published studies also revealed a reduction of max K readings by more than 2 D, while the postoperative spherical equivalent(SEQ) was reduced by an average of more than 1 D and refractive cylinder decreased by about1 D. The major indication for the use of CXL is to inhibit the progression of corneal ecstasies, such as keratoconus and pellucid marginal degeneration. CXL may also be effective in the treatment and prophylaxis of iatrogenic keratectasia, resulting from excessively aggressive photo ablation. This treatment has been used to treat infectious corneal ulcers with apparent favorable results. Most recent studies demonstrate the beneficial impact of CXL for iatrogenic ecstasies, pellucid marginal degeneration, infectious keratitis, bullous keratopathy and ulcerative keratitis. Several long-term and short-term complications of CXL have been studied and documented. The possibility of a secondary infection after the procedure exists because the patient is subject to epithelial debridement and the application of a soft contact lens. Formation of temporary corneal haze,permanent scars, endothelial damage, treatment failure,sterile infiltrates, bullous keratopathy and herpes reactivation are the other reported complications of this procedure.
文摘AIM: To quantify corneal ultrastructure using laser scanning in vivo confocal microscopy(IVCM) in patients with keratoconus and control subjects. METHODS: Unscarred corneas of 78 keratoconic subjects without a history of contact lens use and 36age-matched control subjects were evaluated with slit-lamp examination(SLE), corneal topography and laser scanning IVCM. One eye was randomly chosen for analysis. Anterior and posterior stromal keratocyte,endothelial cell and basal epithelial cell densities and sub-basal nerve structure were evaluated.RESULTS: IVCM qualitatively demonstrated enlarged basal epithelial cells, structural changes in sub-basal and stromal nerve fibers, abnormal stromal keratocytes and keratocyte nuclei, and pleomorphism and enlargement of endothelial cells. Compared with control subjects, significant reductions in basal epithelial cell density( 5817 ± 306 cells / mm2 vs 4802 ±508 cells/mm2,P 【 0. 001), anterior stromal keratocyte density(800 ±111 cells/mm2 vs 555 ±115 cells/mm2, P 【0.001),posterior stromal keratocyte density(333±34 cells/mm2vs270 ±47 cells/mm2, P 【0.001), endothelial cell density(2875 ±223 cells/mm2 vs 2686 ±265 cells/mm2, P 【0.001),sub-basal nerve fiber density(31.2 ±8.4 nerves/mm2vs18.1 ±9.2 nerves/mm2, P 【0.001), sub-basal nerve fiber length(21.4±3.4 mm/mm2 vs 16.1±5.1 mm/mm2, P 【0.001),and sub-basal nerve branch density(median 50.0(first quartile 31.2- third quartile 68.7) nerve branches/mm2 vs median 25.0(first quartile 6.2- third quartile 45.3) nerve branches/mm2, P 【0.001) were observed in patients with keratoconus.CONCLUSION: Significant microstructural abnormalities were identified in all corneal layers in the eyes of subjects with keratoconus using IVCM. This non-invasive in vivo technique provides an important means to define and follow progress of microstructural changes in patients with keratoconus.
基金National Natural Science Foundation of China (No. 81270979)Natural Science Foundation of Jiangsu Province, China (No.BK2012777)
文摘·AIM: To describe the initial outcomes and safety of femtosecond laser-assisted deep anterior lamellar keratoplasty(DALK) for keratoconus and post-LASIK keratectasia.·METHODS: In this non-comparative case series, 10 eyes of 9 patients underwent DALK procedures with a femtosecond laser(Carl Zeiss Meditec AG, Jena,Germany). Of the 9 patients, 7 had keratoconus and 2had post-LASIK keratectasia. A 500 kHz VisuMax femtosecond laser was used to perform corneal cuts on both donor and recipient corneas. The outcome measures were the uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA), corneal thickness,astigmatism, endothelial density count(EDC), and corneal power.·RESULTS: All eyes were successfully treated. Early postoperative evaluation showed a clear graft in all cases. Intraoperative complications included one case of a small Descemet’s membrane perforation.Postoperatively, there was one case of stromal rejection,one of loosened sutures, and one of wound dehiscence.A normal corneal pattern topography and transparency were restored, UCVA and BCVA improved significantly,and astigmatism improved slightly. There was no statistically significant decrease in EDC.· CONCLUSION: Our early results indicate that femtosecond laser-assisted deep anterior lamellar keratoplasty could improve UCVA and BCVA in patients with anterior corneal pathology. This approach shows promise as a safe and effective surgical choice in the treatment of keratoconus and post-LASIK keratectasia.
文摘AIMTo determine the impact of rigid gas permeable (RGP) and silicone-hydrogel keratoconus lenses on the quality of life (QoL) in keratoconus (KCN) patients using the self-reported results from the Contact Lens Impact on Quality of Life (CLIQ) Questionnaire.METHODSFrom January 2013 to April 2013, 27 consecutive KCN patients who wore RGP contact lenses (conflexair100 UV KE Zeiss-Wöhlk) or soft silicone-hydrogel contact lenses (SHCLs) for KCN (KeraSoft IC- Bausch&Lomb or Hydrocone Toris K-Swiss lens) completed the CLIQ questionnaire.RESULTSThe mean age of 27 patients was 29.6±8.0y. Fifteen patients were RGP user. The groups were comparable with respect to the mean patient age, sex, and mean K values (P=0.1, P=0.8 and P=0.1, respectively). The mean CLIQperson measure was 42.8±5.5 in RGP group and 39.6±5.5 in SHCLs for KCN group (P=0.06). CLIQperson measure was positively correlated with steep K value (r=0.301, P=0.04). When eyes were stratified by visual acuity with contact lenses, the mean CLIQperson measure was 42.01±5.6 in eyes with a visual acuity of 20/20-20/25 (n=44) and 38.4±5.26 in eyes with a visual acuity of 20/32 or less (n=10; P=0.097).CONCLUSIONRGP lenses and SHCLs for KCN have similar impact on QoL.
文摘AIM： To evaluate the corneal cell morphology of new keratoconus patients wearing two different types of rigid gas-permeable（RGP） contact lenses for 1y.METHODS： Thirty nine eyes of 39 new keratoconus patients were selected and randomly fitted with two types of RGP contact lenses.Group 1 had 21 eyes with regular rigid gas-permeable（RRGP） contact lens and rest 18 eyes were in group 2 with specially designed rigid gas-permeable（SRGP） contact lens.Corneal cell morphology was evaluated using a slit scanning confocal microscope at no-lens wear and after 1y of contact lens wearing.RESULTS： After 1y of contact lens wearing in group 1,the mean anterior and posterior stromal keratocyte density were significantly less（P=0.006 and P=0.001,respectively） compared to no-lens wear.The mean cell area of anterior and posterior stromal keratocyte were also significantly different（P=0.005 and P=0.001） from no-lens wear.The anterior and posterior stromal haze increased by 18.74% and 23.81%,respectively after 1y of contact lens wearing.Whereas in group 2,statistically significant changes were observed only in cell density ＆ area of anterior stroma（P=0.001 and P=0.001,respectively） after 1y.While,level of anterior and posterior stromal haze increased by 16.67% and 11.11% after 1y of contact lens wearing.Polymegathism and pleomorphism also increased after 1y of contact lens wearing in both the contact lens groups.CONCLUSION： Confocal microscopy observation shows the significant alterations in corneal cell morphology of keratoconic corneas wearing contact lenses especially in group 1.The type of contact lens must be carefully selected to minimize changes in corneal cell morphology.
文摘AIM: To demonstrate the effects of two different types of allergic conjunctivitis on severity of keratoconus (KC). ·METHODS: We retrospectively reviewed the medical records of 171 KC patients referred between June 2010 and June 2011. The KC patients were divided into 3 groups as KC (group A), KC with vernal keratoconjunctivitis (VKC) (group B) and KC with allergic conjunctivitis (AC) (group C). Main outcome measures were demographic and ocular clinical features including age at presentation, gender, spherical equivalent (SE), best spectacle corrected visual acuity (BCVA), mean keratometric measurement (Km), central corneal thickness (CCT), and intraocular pressure (IOP). Groups were compared in term of study variables. · RESULTS: The median age at presentation was significantly lower in group B (P 【0.001). According to the median SE (P =0.003), BCVA(P =0.022), Km(P 【0.001), CCT (P =0.015) and Amsler-Krumeich classification (P 【 0.001), KC was more severe in group B. There was no significant difference in terms of IOP and corrected IOP among the groups (P =0.44), however there were 4 patients who had increased corrected IOP developed after topical corticosteroid use in group B. The differences among the groups persisted even after controlling for age and gender. · CONCLUSION: Our findings demonstrated a more severe KC in VKC patients despite their younger age which suggests evaluation of VKC patients as a separate group in keratoconus disease.
基金Supported by the National Natural Science Foundation of China(No.81670837,No.81170828)the Tianjin Science&Technology Foundation(No.15JCZDJC35300)the Tianjin Health and Family Planning Communication Foundation(No.14KG133)。
文摘The prevalence of keratoconus is 1/2000 in the general population and is high in adolescents.Keratoconus is a progressive disease,which has a great impact on patients’quality of life and mental health.It can be managed by surgical and non-surgical means,rigid gas permeable(RGP)contact lens as its main non-surgical method is widely used in clinic.The efficacy of wearing RGP contact lens has been confirmed to some extent,but some studies have found that wearing RGP contact lens has adverse effects,which may promote disease progression.In this paper,the advantages and disadvantages of RGP contact lens in controlling keratoconus were reviewed to provide more suggestions and references for the clinical application of RGP contact lens.
基金Supported by Natural Science Foundation of Shaanxi Province(No.2017JM8040)Xi’an Science and Technology Project[No.2017116SF/YX010(7)]
文摘AIM:To investigate the expression of visual system homeobox 1(VSX1)and myofibroblast marker alpha smooth muscle actin(α-SMA)in keratoconus(KC).METHODS:Thirty corneal tissue were collected from KC patients after corneal transplantation and 15 normal donor corneas were obtained.All corneal tissues divided into 4 parts for different detections.Scanning electron microscopy was used to observe the ultrastructure of the specimens.VSX1 andα-SMA localization in cornea tissues was detected using immunofluorescence histochemistry.Reverse transcription-quantitative polymerase chain reaction(RT-qPCR)and Western blot were performed to analyze the expression level of VSX1 andα-SMA.RESULTS:Compared to normal cornea tissue,the collagen fibers in KC stroma were distortional and attenuated and keratocytes were abnormally changed.VSX1 andα-SMA located in the corneal stroma.The mRNA and protein expression level of VSX1 in KC were about 3 times as high as that of normal tissue(P<0.001).α-SMA was hardly expressed in the normal corneas,however,its expression in the KC was about 1.5 times higher than that of the normal corneas(P<0.0001).CONCLUSION:Compared with normal corneal the expression of VSX1 andα-SMA in KC both increased.VSX1 is related to the activation of keratocytes and involved in the pathogenesis of keratoconus.
