Predictive factors of epiretinal membrane in complicated rhegmatogenous retinal detachment tamponaded with silicone oil.

AIM: To determine the incidence and predictive factors for epiretinal membrane (ERM) formation in eyes with complicated primary rhegmatogenous retinal detachment (RRD) tamponaded with silicone oil (SO). METHODS: This retrospective case-control study included 141 consecutive patients with (51 eyes) and without (90 eyes) ERM formation after primary pars plana vitrectomy (PPV) and SO tamponade for complicated RRD. The risk factors for ERM were assessed using logistic regression analysis. RESULTS: The prevalence of postoperative ERM was 36.2% (51/141). Multivariate logistic regression analysis showed that the risk factors for ERM in SO-tamponaded eyes included preoperative proliferative vitreoretinopathy [PVR; odds ratio (OR), 2.578; 95% confidence interval (CI) 1.580-4.205, P<0.001], preoperative choroidal detachment (OR, 4.454; 95%CI 1.369-14.498, P=0.013), and photocoagulation energy (OR, 2.700; 95%CI 1.047-6.962, P=0.040). The duration of the preoperative symptoms, intraocular SO tamponade time, giant retinal tear, preoperative vitreous hemorrhage, preoperative best-corrected visual acuity, number of breaks, quadrants of RRD, axial length, and photocoagulation points were not predictive factors for ERM formation. CONCLUSION: Preoperative PVR, choroidal detachment, and photocoagulation energy are risk factors of ERM formation after complicated RRD repair. Better ophthalmic care as well as patient education are necessary for such patients with risk factors.

Multimode imaging characteristics and treatment of uveal schwannoma.

AIM: To delineate the different imaging characteristics of uveal schwannoma from melanoma and discuss the optimal treatment strategy for intraocular schwannoma. METHODS: Case series of three patients diagnosed with intraocular schwannoma was collected at Zhongshan Ophthalmic Center, Guangzhou, China from July 2014 to December 2020. All the study patients underwent ultrasonography and magnetic resonance imaging (MRI). The clinical features, therapeutic strategies, and prognoses of all patients were reviewed. RESULTS: Ultrasonography of all three patients (all females, mean age, 39y, age range, 23-54y) showed low to medium reflectivity with a homogeneous internal structure. MRI of all three patients demonstrated isointensity on T1-weighted imaging spin-echo (T1WI SE) images and hypointense on fast spin-echo T2-weighted images (FSE T2WI) images with respect to the brain. Minimally invasive pars plana vitrectomy (PPV) and local resection of the tumor was performed for all patients, and the diagnosis of schwannoma was confirmed by histopathological examination. CONCLUSION: The present study indicates that ultrasonography and MRI features of uveal schwannoma may contribute to the differentiation of uveal schwannoma from melanoma, and the optimal therapy for intraocular schwannoma is minimally invasive PPV and local resection.

Prevalence and characteristics of peripheral myopic retinopathy in Guangzhou office workers.

AIM: To determine the prevalence and characteristics of peripheral myopic retinopathy among a sample of Guangzhou office workers. METHODS: A cross-sectional study of Guangzhou Chinese office works in different departments and units of the Guangzhou Power Supply Bureau, China, in 2016. Myopic retinopathy was recorded and analyzed with a scanning laser ophthalmoscope and by slit-lamp microscopy combined with a three-mirror contact lens. RESULTS: In total, 1910 eyes of 955 subjects (508 females and 447 males) aged 21-59y were included; 69.6% of these eyes were myopic. The myopia group had a younger age and worse uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA) when compared with hyperopia and emmetropia groups (P<0.001). The axial length (AL) was significantly longer, the spherical equivalent (SE) was more serious, and the optic nerve crescent was significantly larger in subjects with myopia than with hyperopia and emmetropia. Subjects with myopia, and especially high myopia, had the highest frequency of myopic retinal 18 changes (49.4%, P<0.001) [white-without-pressure (43.8%, P<0.001), lattice degeneration (4.5%, P=0.044)] among the three groups. Logistic regression confirmed that any myopia (OR: 3.41, P<0.001) [mild myopia (OR: 1.93, P=0.001), moderate myopia (OR:3.64, P<0.001), and high myopia (OR:10.58, P<0.001)], a greater AL (OR: 1.55, P<0.001) and a much higher SE (OR: 0.77, P<0.001) increased the risk for peripheral retinal changes. CONCLUSION: Myopia-related retinal changes are positively associated with greater AL, higher SE, and myopia.

Rac1 modulates the vitreous-induced plasticity of mesenchymal movement in retinal pigment epithelial cells.

BACKGROUND: The vitreous has been shown to induce epithelial-mesenchymal transdifferentiation because it induces fibroblast-like morphology, enhanced migration and invasion in retinal pigment epithelial cells in proliferative vitreoretinopathy. Rac1 is the principal mediator of cell migration. In the current study, the relationship between Rac1 and cell migration, and invasion in vitreous-transformed retinal pigment epithelial cells was investigated using NSC23766, a specific inhibitor of Rac guanosine-5'-triphosphatase activity, and the involvement of a Rac1 guanosine-5'-triphosphatase-dependent pathway was detected. DESIGN: One-way design with multiple levels and repeated measurement design. PARTICIPANTS AND SAMPLES: The vitreous humor was collected from 20 healthy donor eyes and the retinal pigment epithelial cells were obtained from 9 healthy donor eyes. METHODS: Human low-passage retinal pigment epithelial cells were treated with normal medium or 25% vitreous medium. Rac1 activity was measured using a pull-down assay. The cytotoxicity of NSC23766 was measured using the trypan blue dye exclusion test. Cell migration was measured using a wound healing assay. Cell invasion was determined using a transwell invasion assay. Protein expression of Rac1 and phosphorylation of LIM kinase 1 and cofilin were detected by Western blot analysis. MAIN OUTCOME MEASURES: Cell migration, invasion, Rac1 activity and phosphorylation of LIM kinase 1 and cofilin. RESULTS: Rac1guanosine-5'-triphosphatase was activated in vitreous-transformed retinal pigment epithelial cells. A Rac inhibitor suppressed vitreous-induced migration and invasion in retinal pigment epithelial cells. Cofilin phosphorylation was activated by vitreous treatment but blocked by NSC23766. CONCLUSIONS: Rac1 mediates vitreous-transformed retinal pigment epithelial cells' plasticity of mesenchymal movement via Rac1 guanosine-5'-triphosphatase-dependent pathways that modulate LIM kinase 1 and cofilin activity. Rac inhibition may be considered a novel treatment for proliferative vitreoretinopathy.

Pro370Leu myocilin mutation in a Chinese pedigree with juvenile-onset open angle glaucoma.

PURPOSE: To investigate the genotype and phenotype of juvenile-onset open angle glaucoma (JOAG) in a Chinese family (PN pedigree). METHODS: Each family member was comprehensively examined by an experienced ophthalmologist. The clinical characteristics of the family patients with JOAG were documented. Blood samples were obtained from 22 available participants from the PN pedigree. Linkage analysis was performed to identify the possible chromosome loci. The presence of gene mutation was ascertained by polymerase chain reaction amplification and subsequent direct sequencing. RESULTS: The affected members in the PN pedigree are characterized by early age of onset (mean age at diagnosis is 17 years old), severe clinical presentations, high intraocular pressure (mean IOP of 34.18±2.97 mmHg), and poor response to pharmacological treatment (87.5% of the patients required filtering surgery). The region on chromosome 1 between D1S3464 and D1S1619 was identified in this pedigree by linkage analysis. A Pro370Leu myocilin mutation resulting from a heterozygous C→T transition at the 1,109th nucleotide in exon 3 was detected by gene sequencing. The Pro370Leu mutation co-segregated among all affected individuals of PN pedigree. CONCLUSIONS: The GLC1A Pro370Leu mutation is firmly correlated with a severe POAG phenotype. These data provide clues for the severe disease-causing nature of the Pro370Leu allele. Gene screening may be a useful method for pre-symptom diagnosis and a forewarning to detect the at-risk individuals in familial open-angle glaucoma patients, especially in pedigrees of early-onset.

Comparison of FP-7 and S-2 Ahmed glaucoma valve implantation in refractory glaucoma patients for short-term follow-up.

BACKGROUND: Ahmed glaucoma valves (AGV) has been used for decades, but there is no detailed report about the efficacy of AGV in Chinese glaucoma patients. This study aimed to compare the intraocular pressure (IOP) lowering efficacy and side effects of S-2 polypropylene and PF-7 silicone AGV implantation in Chinese refractory glaucoma patients. METHODS: Patients were divided into S-2 model AGV group and FP-7 model AGV group. The complete and qualified surgical success rate, change of IOP, number of anti-glaucoma medications used and postoperative complications were recorded and analyzed. RESULTS: Average follow-up time was comparable between two groups. IOP was reduced from (37.9 ± 12.7) mmHg preoperatively to (17.3 ± 5.3) mmHg at the last follow-up in S-2 group and reduced from (39.9 ± 14.4) mmHg to (17.7 ± 4.9) mmHg in FP-7 group. Anti-glaucoma medications were reduced from 3.8 ± 0.2 to 1.5 ± 0.2 in S-2 group, and 3.5 ± 0.2 to 0.7 ± 0.2 in FP-7 groups. The cumulative success rates were comparable in two groups, which were 61.2% and 72.1% in S-2 group and FP-7 group respectively. When IOP reduction criteria was used, complete success rates were 30.6% and 51.2% for S-2 and FP-7 groups, and qualified success rates were 86.1% and 92.7% separately. In both groups, the major complication was hypotony, and the previous trabeculectomy of patients was the major risk factor for surgery failure. CONCLUSIONS: In this short-term retrospective study, S-2 AGV is showed at least as effective as FP-7 AGV in IOP reduction, but associated with higher rate of complications. Previous trabeculectomy is a principle risk factor for AGV implantation failure. These clinical outcomes are important for converting use of the FP-7 silicon AGV in Chinese refractory glaucoma patients.

[Clinical efficacy and safety of FP-7 Ahmed glaucoma valve implantation in neurovascular glaucoma patients].

OBJECTIVE: To evaluate the efficacy and safety of FP-7 Ahmed glaucoma valves (AGV) implantation in neurovascular glaucoma (NVG) as the first choice of surgery. METHODS: This retrospective, comparative case series study collected a total of 36 eyes of 36 patients with neurovascular glaucoma who underwent AGV implantation in Zhongshan Ophthalmic Center from January 2009 to June 2010. Change of intraocular pressure (IOP), the best corrected visual acuity, numbers of anti-glaucoma medication, success rate and postoperative complications were followed up at day 1, week 1, month 1, and every 3 months after surgery. Complete success of surgery was rated as reduction of IOP ≥ 30% without medication and those who failed to meet criteria was rated as partial success. Data were analyzed by paired Student t-test for IOP, rank sum test for paired non-parametric numbers of medication, and repeated measures analysis of variance for comparison of IOP between different time points using SPSS 13.0. RESULTS: Compared with pre-operation, IOP was significant (F = 9.26, P < 0.05) decreased after surgery with FP-7 AGV implantation (39.5 ± 9.7) mm Hg (1 mm Hg = 0.133 kPa) vs (9.2 ± 8.9), (11.8 ± 3.8), (13.7 ± 4.8), (16.9 ± 5.3), (16.9 ± 6.8) mm Hg at day 1, week 1, month 1, month 3 and the last following-up of post-operation, respectively. The numbers of anti-glaucoma medication were significantly (Z = 6.764, P < 0.05) reduced from 4.0 (1-6) of pre-operation to 1.0 (1-3) of post-operation. At the last following up, the complete success rate after FP-7 AGV implantation was 80.6%, and qualified success rate was 91.7%. The postoperative complications including occlusion of the drainage tube, exposure of the drainage tube, shallow anterior chamber and encapsulated cystic blebs around the plate were controlled with additional treatment. CONCLUSIONS: The clinical outcome indicated that the implantation of FP-7 AGV has a stable IOP lowering effect and fewer complications, which can be considered as one of the first choices for management of NVG.

[Gene screening as the forewarning measure to predict glaucoma].

OBJECTIVE: To investigate the effect of gene screening on forewarning and monitoring of familial open-angle glaucoma pedigree. METHODS: Comprehensive ophthalmic examinations were performed in all available family members. The genomic DNA was extracted from peripheral blood. The myocilin gene was amplified and screened for mutations using direct sequencing. All family members were followed up. RESULTS: Among 12 family members, 5 individuals carry a C to T transition in exon 3 resulting in the substitution of proline to leucine (Pro370Leu), and the other 7 individuals did not carry this mutation. Ophthalmic examinations did not show any abnormality in the optic disc, the thickness of RNFL, and visual field parameters in mutation-carriers. During the follow-up, all carriers were diagnosed as open-angle glaucoma. The mean time of presentation of the defect of visual field was 21.6 months and 14.4 months after the changes in RNFL thickness. CONCLUSION: Genetic diagnosis was proven to be a method with high specificity and sensitivity; and can be used for presymptom diagnosis and forewarning in familial open-angle glaucoma pedigree.

Pro370Leu MYOC gene mutation in a large Chinese family with juvenile-onset open angle glaucoma: correlation between genotype and phenotype.

PURPOSE: Glaucoma is the leading cause of irreversible blindness worldwide. Most of the cases are primary open angle glaucoma (POAG). POAG is a genetically heterogenous disease; autosomal dominance is the most frequent type of monogenic inheritance. In this study, we identified the genotype of a MYOC mutation and investigated the phenotype of a Chinese juvenile-onset open angle glaucoma (JOAG) pedigree (GZ.1 pedigree). METHODS: Blood samples were obtained from 24 participants. We performed sequence and gene linkage analysis in the GZ.1 pedigree retrospectively. Comprehensive ophthalmologic examinations were performed for each family member. Pharmacological treatment or filtering surgery was performed as needed according to the intraocular pressure (IOP) of each individual. RESULTS: A Pro370Leu myocilin mutation located in exon 3 of MYOC was identified in 24 members of the GZ.1 pedigree. Sixteen patients had juvenile-onset primary open-angle glaucoma (JOAG), and the others participating in the project had no such genotype. Analysis of polymorphic microsatellite markers indicated that the disease in GZ.1 is autosomal dominant inheritance. The patients in GZ.1 are characterized by early age of onset (before 35 years of age), severe clinical presentations, and high intraocular pressure unresponsive to pharmacological treatment; requiring 89.5% of the patients to undergo filtering surgery. Fortunately, the success rate of surgery was high. None of the patients required further medical treatment and only one demonstrated low IOP fundus changes. CONCLUSIONS: This is the first evidence of a founder effect for a Pro370Leu myocilin mutation in a Chinese POAG pedigree. The family with the Pro370Leu myocilin mutation presents with juvenile-onset glaucoma. After 10 years of follow-up, it is evident that the mutation is closely associated with the phenotype of the patients. Analysis of MYOC in JOAG patients may enable the identification of at-risk individuals and help prevent disease progression toward the degeneration of the optic nerve, and may also contribute to genetic counseling.

Analysis of MYOC gene mutation in a Chinese glaucoma family with primary open-angle glaucoma and primary congenital glaucoma.

BACKGROUND: Glaucoma is one of the leading causes of blindness in the world. Primary open-angle glaucoma (POAG) and primary congenital glaucoma (PCG) are subtypes of glaucoma. Myocillin is the first gene identified to be involved in POAG. Recently, myocillin mutation has been found in PCG. In this context, we reported a special glaucoma pedigree, which was composed of both PCG and POAG patients, and analyzed the mutation of myocillin in this pedigree. METHODS: The family was composed of the parents, a son and a daughter. All members of the family underwent the complete ophthalmologic examinations. All coding exons 1 - 3 and flanking introns of myocilin gene were screened for sequence alterations by polymerase chain reaction and direct DNA sequencing. RESULTS: The son was the proband, who was diagnosed as PCG in both eyes. The father was diagnosed as POAG in the right eye, the left eye was still normal. Both the sister and the mother of the proband had normal intraocular pressure without glaucomatous optic disc changes. The mutations in intron 2 of myocilin gene were detected in the family. While the proband and the father were homozygous, the mother and the sister were heterozygous for the mutation. CONCLUSIONS: Homozygous mutation in intron 2 of myocilin gene is involved in both POAG and PCG. It is suggested that the pathogenesis might be overlapping in POAG and PCG.

[Anti-proliferative effect of herpes simplex virus thymidine kinase gene system on human Tenon capsule fibroblasts in vitro].

OBJECTIVE: To observe anti-proliferative effect of herpes simplex virus thymidine kinase gene system (HSV-tk) on human Tenon capsule fibroblasts (HTFs) and it's mechanism. METHODS: Retroviral vector was constructed containing HSV-tk gene and transfer to packaging cell line PT67. The positive clones was selected with G418 and the supernatant was collected which contains virus particles. The titer of the virus was also calculated. The virus particles were verified by transmission electron microscope (TEM). PCR was carried out to detect the integrity of tk gene into viral DNA genome. HTFs cells were infected with the virus and the positive clones were selected for propagation culture. RT-PCR and Western blot were used to detect tk gene expression. The anti-proliferative effect of tk gene on HTFs cells was determined by MTT. Apoptosis of cells was detected by Hoechst 33258 DNA staining and flow cytometry. The morphologic changes of the cell were observed by TEM. RESULTS: The retroviral vector pL (tk) SN was constructed successfully which was verified by enzyme cutting. The shape of virus particles derived from the package cells appeared to be oval or spherical under TEM with the diameter around 100 nm. The tk gene was detected in the viral DNA genome by PCR. The virus titer was 4 x 10(7) cfu/ml. The expression of tk gene was detected by RT-PCR and Western blot both in mRNA and protein level. The anti-proliferative effect of tk gene on HTFs cells was dose-dependent, all cells were died 5 days after 5 x 10(-3) g/L GCV being added, IC50 = 6 x 10(-4) g/L. Both necrosis and apoptosis were observed in this study and the apoptosis rate was increased with increasing dose of GCV. CONCLUSIONS: The proliferation of HTFs cells in vitro could be effectively inhibited by the killing effect of HSV-tk-GCV system through the pathway of necrosis and apoptosis.

[Induction of epidermal stem cells of rhesus monkey into human conjunctival epithelial cells: an in vitro experiment].

OBJECTIVE: To observe the possibility of inducing the epidermal stem cells of rhesus monkey into human conjunctival epithelial cells and to investigate the plasticity of epidermal stem cells. METHODS: Epidermal stem cells of rhesus monkey were cultured in vitro and separated with type IV collagen. The cells were analyzed before and after isolation with beta1 integrin and keratin 15 by flow cytometry. The separated stem cells were characterized with markers, beta1 integrin and keratin 15 by immunohistochemistry and RT-PCR. The stem cells were transfected by green fluorescent protein (GFP) gene. 24 hours later, the fluorescent cells were selected out and co-cultured with human conjunctival epithelial cells in Transwell for 10 days. Then the cells were characterized with the markers of beta1 integrin, keratin 15, mucin 4 and keratin 4 by immunohistochemistry and RT-PCR. RESULTS: The purity of the separated epidermal stem cells was almost 90%, and all the cells were positive of beta1 integrin and keratin 15. After being transfected with GFP gene for 24 hours, the cells expressed green fluorescence. 10 days later, after co-culture with human conjunctival epithelial cells, the epidermal stem cells were positive of mucin 4 and keratin 4. CONCLUSION: Epidermal stem cells of rhesus monkey can be induced into conjunctival epithelial cells in vitro by co-culturing with primary passage conjunctival epithelial cells.

[A preliminary study on gene mutation and its function in a large family (GZ.1 pedigree) with open-angle glaucoma].

OBJECTIVE: To determine the causative mutation of myocilin gene and to investigate its pathogenic function in a large Chinese pedigree (GZ.1) with familial open-angle glaucoma. METHODS: Genome-wide scanning was performed and the Lod scores were calculated. Candidate gene was amplified and screened for mutations using direct sequencing. To elucidate its expression, distribution and cytotoxicity of mutant myocilin, human trabecular cells (HTM) cells were transfected with pcDNA-wild-type and mutant myocilin vectors using liposomes. RESULTS: Mutation analysis of the myocilin gene showed a C-to-T transition at the 1, 109 th nucleotide in exon 3 resulting in a change of amino acid from proline to leucine (Pro370Leu). This mutation cosegregated with all affected individuals (16/16) and never presented in unaffected individuals (0/8). In transfected HTM cells, the mutant myocilin protein was not correctly processed in ER and accumulated as aggresome-like structures in the cytoplasma instead of being secreted. In addition, the expression of mutant protein also led to apoptosis of trabecular cells and the occurrence of. CONCLUSION: The mutation of Pro370Leu in myocilin gene could cause the accumulation of misfolding myocilin protein in HTM cells, which might lead to glaucoma in GZ.1 pedigree.

[Preliminary study of inhibition of human Tenon's capsule fibroblasts in vitro by RNA interference targeting IKK-beta].

OBJECTIVE: To determine whether small interference RNA (siRNA) targeting the inhibitor of kappaB kinase-beta (IKK-beta) could be used to suppress the IKK-beta expression, and inhibit the proliferation of human Tenon's capsule fibroblasts in vitro. METHODS: IKK-beta specific siRNA designed from the human gene sequence was transfected into the cultured human Tenon's capsule fibroblasts, and a non-targeted siRNA was transfected as a negative control. The mRNA of IKK-beta was assessed by reverse transcription-polymerase chain reaction (RT-PCR), and the protein expression was determined by Western blotting. Cell viability of the cultured human Tenon's capsule fibroblasts with series of RNA interference at 5, 10, 25, 50, 100, and 200 nmol/L was evaluated by MTT assay 48 hours after transfection. RESULTS: The expression of IKK-beta was significantly (P < 0.05) suppressed at both mRNA and protein levels after transfection. The proliferation of the cultured human Tenon's capsule fibroblasts was inhibited at all the transfected concentrations at different rates (10.72%, 23.35%, 30.84%, 51.25%, 50.06% and 49.63% respectively). The highest level of inhibition was observed at 50 nmol/L of siRNA concentration. CONCLUSIONS: IKK-beta specific siRNA is effective in suppressing the IKK-beta expression and inhibiting the proliferation of the cultured human Tenon's capsule fibroblasts. RNA interference may offer a new alternative to post-operational management of scar tissue formation.