Objective To review research progress of corneal tissueengineering.Methods The recent articles on corneal tissue engineering focus on source and selection of corneal cells, the effects of growth factors on culture of corneal cells in vitro. The preparation and selection of three-dimensional biomaterial scaffolds and their b and weak points were discussed. Results The corneal tissue engineering cells come from normal human corneal cells. The embryo corneal cell was excellent. Several kinds of growth factors play important roles in culture, growth and proliferation of corneal cell, and incroporated into matrix.Growth factors including basic fibroblast growth factor, keratinocyte growth factor, transforming growth factor β1 and epidermal growth factor was favor to corneal cell. Collagen, chitosan and glycosaninoglycans were chosen as biomaterial scaffolds. Conclusion Human tissue engineering cornea can be reconstructed and transplanted. It has good tissue compatibility and can be used as human corneal equivalents.
In order to rescue the serious cornea-sclera defect, normal piece of a sclera from the damaged eye was used to serve as a donor material to repair the cornea-sclera defect. Eighteen cases were treated by transplantation of sclera graft with the operation to decompress the intra-ocular tension and to perform an artificial pupil from 1979 to 1994. Because the ocular-store seriously lacks in mostly internal locality, in the 18 cases, laceration of avulsive in 5 cases, severe corneal fistula complicated to other corneal diseases in 8 cases, locolized staphyloma of aornea in 2, laceration of sclera fistula in 1. The resulte were: The repairs were all healed up in an average of 20 days. The tension returned to normal and the vision was improved. The scleral graft was fused with the cornea, and the white area form the graft tended to reduce in size gradually with increase in transparency. There was no sign of iritis and rejection reaction. Follow-up of 3 to 36 months showed that the grafting operation was simple and an easy method, at the same time, once gained effect if would prevent or cure blindness.
Objective To investigate the influence of undercorrected orthokeratology on myopia control, and the correlation between target and central corneal epithelial damage. Methods A retrospective study was conducted on 22 undercorrected orthokeratology lens wearers (37 eyes) from January 2016 to February 2017, and 25 full corrected wearers (47 eyes) during the concurrent period were randomly selected as the control group. The changes of axial length before and after orthokeratology lens wearing and the within-6-month central corneal epithelial damage after orthokeratology lens wearing were analyzed. Results The average annual increase of axial length was (0.13±0.15) mm in the undercorrected group, and (0.14±0.16) mm in the full corrected group, the difference was not statistically significant (P>0.05). Multiple linear regression analysis showed that there was no correlation between the axial growth and the undercorrection of the target (P>0.05), but a negative correlation between the axial growth and the age (P<0.01). After using orthokeratology, the average annual growth of the axial length in children aged 7-10 years was (0.25±0.16) mm, and (0.10±0.14) mm in children aged 11-15 years, the difference was statistically significant (P<0.01). The incidence of central corneal epithelial punctate staining in the (–4.25)-(–5.00) D target group was 27.08%, and that in the (–3.00)-(–4.00) D target group was 16.67%, the difference was not statistically significant (P>0.05). Conclusions The effect of orthokeratology on myopia growth is not affected by the undercorrected target, not related to the undercorrection of target, but negatively correlated with the age. Undercorrected orthokeratology can still be used for myopia control in high myopia patients. No correlation is found between the target and central corneal staining.
Objective To observe the effects on rabbit corneas and retinas after single intravitreal injection of voriconazole at different doses. Methods According to the randomization table, 25 healthy rabbits were randomly divided into control group, and voriconazole 50, 100, 200, and 400 μg groups. Therefore, there were 5 rabbits in each group. The eyes of control group received intravitreal injection of 0.1 ml balanced saline solution, and those treatment groups received 0.1 ml voriconazole injection of corresponding dose. Before the injection and 1, 7, and 14 days after the injection, endothelial cell counts and corneal thicknesses were measured; full-field electroretinogram were performed and b-wave amplitudes in maximal combined reaction (Max-R) were recorded. On 14 days after the injection, histologic structures were observed by light microscope and transmission electron microscope. Results There was no significant difference in endothelial cell counts (F=0.320, 0.291, 0.467, 0.649) and corneal thicknesses (F=0.214, 0.284, 0.360, 0.225) with those of control group at any time points (P > 0.05). Before and 1 day after the injection, b-wave amplitudes of each voriconazole group had no significant difference compared with those of control group (F=0.220, 0.106; P > 0.05). On 7 days after the injection, b-wave amplitudes decreased significantly at doses of 200 μg and 400 μg (P < 0.05). On 14 days after the injection, there was no significant difference between the the amplitude of 200 μg group and that of control group (P > 0.05). However, the amplitude of the 400 μg group decreased continuously and there was still significant difference (P < 0.05). Light microscopy did not reveal any corneal abnormality in both control group and voriconazole groups. The retinas were normal except that of the 400 μg group, which hadathinner and degenerated inner nuclear layer and disordered photoreceptor layer. Under transmission electron microscope, there were no ultrastructure damages of corneas in both control group and voriconazole groups, either. The rabbit retinas of the 50 μg and 200 μg group have normal inner nuclear layer and photoreceptor layer, but degrees of changes in both layers were observed in the eyes of 200 μg and 400 μg group. Conclusions There is no obvious effects on rabbit corneas and retinas after single intravitreal injection of voriconazole at he dose less than or equal 100 μg. There are no obvious effects on rabbit corneas at the dose of 200 μg and 400 μg, while there are damages to the retinas in both functions and histological structures.
Objective To observe the efficacy of photodynamic therapy for vitelliform macular dystrophy(VMD) with choroidal neovascularization(CNV). Methods The clinical data of 7 patients (7 eyes) of VMD with CNV who had undergone photodynamic therapy (PDT) were retrospectively analyzed. The patients were 4 males and 3 females, aged from 20 to 54 years. The patients received the examinations of best corrected visual acuity (BCVA), slitlamp microscopy, fundus photography, fluorescein angiography (FFA), indocyanine green angiography (ICGA), spectral domain OCT(SD-OCT), electrooculogram（EOG）and electroretinogram (ERG)before and after PDT. The BCVA ranged from finger counting to 0.6. Retinal edema and the subretinal fluid were observed. The mean thickness of central retina was (506.00plusmn;30.71) mu;m. PDT was performed according to the standard treatment. The follow-up period ranged from 2 to 11 months with the mean of 6.3 months. The changes of BCVA, CNV and side effects were observed after treatment. Results BCVA improved in all patients ranging from 0.12 to 1.0. The regression of the CNV and resolution of the subretinal fluid were observed by FFA, ICGA and SD-OCT after PDT. The mean thickness of central retina was reduced to (401.00plusmn;52.22) mu;m. There was no PDTassociated ocular or systemic side effect. Conclusions PDT is an effective and safe treatment for VMD with CNV. It may improve or stabilize the visual acuity.
Objective To observe the corneal nerve fibres damage in different stage of diabetic retinopathy (DR) with type 2 diabetes. Methods A cross-sectional study. One hundred and twenty eyes of 120 patients with type 2 diabetes served as diabetes group. According to International Clinical Diabetic Retinopathy Disease Severity Scales (2002), diabetes patients were classified into 4 subgroups: patients without diabetic retinopathy (NDR), patients with mild or moderate non-proliferative diabetic retinopathy (mNPDR), patients with severe non-proliferative diabetic retinopathy (sNPDR) and patients with proliferative diabetic retinopathy (PDR), each subgroup has 30 eyes of 30 patients. Another 30 eyes of 30 healthy participants served as control group. All eyes were scanned with HRT3 in vivo corneal confocal microscopy. Images of sub-basal nerve plexus were quantified including nerve fiber length (NFL), nerve fiber density (NFD), nerve fiber branch density (NFB), and nerve tortuosity (NT). The correlations of corneal nerve fiber with age, duration of diabetes and glycated hemoglobin (HbA1c) were analyzed using Spearman correlation analysis. Results NFL, NFD and NFB were found to be significantly lower in diabetic patients (F=147.315, 142.586, 65.898;P=0.000, 0.000, 0.000), NT was significantly greater in diabetic patients (F=39.431,P=0.000), when compared to control group. In diabetic patients, NFL, NFD and NFB were gradually reduced with DR severity, NT was gradually increased with DR severity. While the difference of NFL, NFD, NFB, NT was not statistically significant between sNPDR and PDR subgroups (P＞0.05), but was statistically significant between other subgroups (P＜0.05). Spearman correlation analysis results showed that age (r=－0.071, －0.080, 0.001, 0.100;P=0.391, 0.328, 0.991, 0.224) and HbA1c (r=－0.109, －0.115, －0.126, 0.025;P=0.238, 0.211, 0.169, 0.781) had no correlation with NFL, NFD, NFB, NT. Duration of diabetes was negatively correlated with the NFL, NFD (r=－0.212, －0.264;P= 0.020, 0.004), positive correlated with NT (r=0.261,P=0.004), and had no correlation with NFB (r=－0.119,P=0.194). Conclusions Corneal nerve fiber loss and nerve tortuosity increased were found in patients with type 2 diabetes, and even without diabetic retinopathy. The progress of corneal neuropathy was correlated with the severity of DR, but it was not change significantly between sNPDR and PDR.
ObjectiveTo investigate the changes in the nerve fiber layer of the cornea in patients with demyelinating optic neuritis (DON) and its correlation with visual acuity. MethodsA cross-sectional study. From March 2021 to July 2022, 27 cases (39 eyes) of DON patients diagnosed in the Department of Neurology and Ophthalmology of Beijing Tongren Hospital Affiliated to Capital Medical University were enrolled in this study. According to the serological test results, the patients were divided into aquaporin 4 antibody associated optic neuritis (AQP4-ON group) and myelin oligodendrocyte glycoprotein antibody associated optic neuritis (MOG-ON group), with 15 cases (19 eyes) and 12 cases (20 eyes) respectively. According to previous history of glucocorticoid treatment, the patients were divided into glucocorticoid treated group and non-glucocorticoid treated group, with 17 cases (27 eyes) and 10 cases (12 eyes) respectively. Twenty healthy volunteers (20 eyes) with age- and gender-matched were selected as the control group. All eyes underwent best corrected visual acuity (BCVA) and in vivo confocal microscopy (IVCM) examinations. BCVA was performed using Snellen's standard logarithmic visual acuity chart, which was converted into logarithmic minimum angle resolution (logMAR) visual acuity during statistics. The corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve fiber branch length (CNBL), corneal nerve fiber branch density (CNBD) and the density of corneal dendritic cells (DC) were detected by IVCM examination. Parameter comparison between groups by t-test and Kruskal-Wallis rank sum test. The correlation between logMAR BCVA and pamameters of corneal nerve fibers were analyzed using Spearman analysis. ResultsThe CNFL, CNFD, and CNBL of the DON group and the control group were (10.67±2.55) mm/mm2, (57.78±12.35) root/mm2, (3.27±1.34) mm/mm2, and (13.74±3.05) mm/mm2, (70.95±13.14) root/mm2, and (4.22±1.03) mm/mm2, respectively; the difference in CNFL, CNFD, and CNBL between the two groups were statistically significant (t=4.089, 3.795, 2.773; P＜0.05). The CNFL, CNBL, and CNBD of the affected eyes in the MOG-ON group and AQP4-ON group were (12.02±2.13) mm/mm2, (3.80±1.19) mm/mm2, (47.97±8.86) fibers/mm2, and (9.25±2.19) mm/mm2, (2.72±1.19) mm/mm2, (39.43±13.86) fibers/mm2, respectively; the differences in CNFL, CNBL, and CNBD between the two groups were statistically significant (t=－4.002, －2.706, －2.306; P＜0.05). The corneal DC density of the patients in the hormone treated group and the non-hormone treated group was (24.43±8.32) and (41.22±9.86) cells/mm2, respectively. The difference in corneal DC density between the two subgroups was statistically significant (P＜0.001). Correlation analysis showed that there was a significant negative correlation between logMAR BCVA and CNBL and CNFL in patients with DON (r=－0.422, －0.456; P＜0.05). ConclusionsThere are different degrees of corneal nerve fiber damage in patients with different types of DON. There was a negative correlation between BCVA and the length of corneal nerve fibers.
Ocular neovascularization is a pathological change in various ocular diseases such as diabetic retinopathy, retinopathy of prematurity, central retinal vein occlusion and age-related macular degeneration, which seriously affects patient's vision. β receptors are expressed in conjunctiva, corneal epithelial cells, corneal endothelial cells, extraocular muscles, trabecular meshwork, ciliary muscle, lens and retina. β adrenergic receptor antagonists bind to β receptors to exert anti-angiogenic effects by inhibiting the expression of vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1, interleukin-6 and other angiogenic cytokines; reducing macrophage-related inflammatory response; increasing the expression of anti-angiogenic factors. In the treatment of corneal neovascularization, choroidal neovascularization, and retinopathy of prematurity, it can significantly reduce the area of neovascularization and delay disease progression. Co-administration of anti-VEGF drugs can reduce the frequency of administration of anti-VEGF drugs. At effective therapeutic concentrations, β-adrenergic receptor antagonists are well tolerated; they have broader targets than anti-VEGF drugs, which offers new treatment strategies for ocular neovascularization such as corneal, choroidal and retinal neovascularization.
Objective To evaluate glaucoma and anterior chamber angle changes after intravitreal silicone oil injection(SOI). Methods The intraocular pressure(IOP) and anterior chamber angles of 34 e yes(33 patients)undergone pars plana vitrectomy and SOI were observed. Results Glaucoma occurred in 9 eyes(26%),in which silicone oil glaucoma(SOG) accounted for 77%(7/9).The changes of the superior part of anterior chamber angle were peripheral anterior synechiae in 11 eye(32%) and SO emulsification droplets in 22 eyes(64%) in 1～4.5 months after surgeries.Glaucoma occurred in 6 eyes of 7 eyes undergone peripheral iridectomy at the inferio r part of the iris after the closure of iridectomy holes (plt;0.05). Conclusion High incidence of glaucoma was found in this series of patients after intravitreal silicone oil injection,and the main causes of SOG were closure of the inferior iridecomy hole and silicone emulsification. (Chin J Ocul Fundus Dis, 2001,17:105-107)
Objective To investigate the feasibility of photochemical tissue bonding (PTB) technique in repairing limbal stem cell (LSC) deficiency and the effect on cornea wound healing. Methods LSCs were isolated from limbus of New Zealand rabbits by tissue block culture method, and then the LSCs of 2nd passage were cultured on de-epithelialized human amniotic membrane (HAM) for 3 weeks to prepare the HAM/LSC grafts. The LSC deficiency models of the left eyes were established by 0.5 mol/L NaOH in 24 New Zealand female rabbits, aged 3-4 months and weighing 1.5-2.0 kg. HAM/LSC grafts were used to repair the cornea wounds by sutures (suture group, n=12) or by PTB technique (PTB group, n=12). The gross was observed including the corneal transparency, erythema, and new blood vessel formation after surgery. At 3 and 28 days, the inflammatory cytokine of interleukin 1β (IL-1β), IL-6, and tumor necrosis factor α (TNF-α) were assayed by ELISA method; and the amount of new blood vessels were quantified by immunohistochemistry staining at 28 days. Results All animals survived to the end of the experiment. At 3 days, there was no obvious difference in the corneal transparency between 2 groups; at 28 days, the corneal transparency of PTB group was higher than that of suture group, and new blood vessels decreased. HE staining showed that mass inflammatory cells infiltrated between graft and cornea basal layer at 3 days, and no new blood vessel formed. inflammatory cells infiltration significantly decreased at 28 days in PTB group; the amount of new blood vessels was (2.0 ± 0.8)/ HP in PTB group and was (6.3 ± 1.3)/HP in suture group, showing significant difference (t=7.966, P=0.002). At 28 days, the concentrations of inflammatory cytokine of IL-1β, IL-6, and TNF-α in suture group were significantly higher than those in PTB group (P lt; 0.05); however, no significant differences were observed between 2 groups at 3 days (P gt; 0.05). Conclusion PTB technique can be used to fix HAM/LSC grafts, which can decrease inflammatory cell infiltration and new vessel formation, and improve the outcomes when compared with suture technique.