Comparison of the effects of EGF, FGF-b, and NGF on the proliferation, migration, and reprogramming of primary rat Müller cells.

Purpose: During the healing process of full-thickness macular holes (FTMHs), the closure and recovery of the hole depend on the migration, proliferation, and activation of Müller cells to promote the closure of holes and restoration of the photosensitive layer. In this study, we investigated the ability of the epidermal growth factor (EGF), fibroblast growth factor-basic (FGF-b), and nerve growth factor (NGF) to influence this process by regulating proliferation, migration, and reprogramming of primary rat Müller cells. Methods: Cell proliferation was measured using CCK8 [2- (2-Methoxy-4-nitrophenyl)-3- (4-nitrophenyl)-5- (2,4-disulfophenyl)-2H-tetrazolium Sodium Salt] colorimetric assays and EdU [5-Ethynyl-2'-deoxyuridine] assays over 48 h. Cell migration was measured using scratch-wound assays and transwell migration assays over 48 h. In addition, we conducted Western blot assays and immunofluorescence assays on cells that were specially treated for 1, 3, and 5 days for cell reprogramming. The percentage of EdU-positive cells in Nestin-positive have also been tested by co-immunofluorescence (Co-IF) staining. Results: EGF and FGF-b significantly promoted the proliferation of Müller cells (p < 0.05) at a concentration of 0-50 ng/mL, but NGF did not (p > 0.05), compared to untreated controls. Exogenous FGF-b and EGF promote the reprogramming of primary rat Müller cells, significantly enhancing the neural stem cell marker Nestin after stimulation on the 1st, 3rd, and 5th days, respectively. The expression of Müller cell marker Vimentin was significantly (p < 0.05) reduced during this period compared to the control group. However, there was no significant difference between the NGF and control groups. Furthermore, the EGF group expressed stronger Nestin expression than the SCM group. The Co-IF staining showed that early 50% of activated cells came from newly proliferating cells on the 5th day. Conclusion: These observations suggest that FGF-b can promote the activation of Müller cells in a short time and enhance the possessive features of neural stem cells, while EGF may act for a longer period of time. This may further the understanding of growth factor therapy in treating FTMHs, and Müller glia may be promising candidates for cell replacement therapy.

Efficacy and Safety of Biosimilar QL1207 vs. the Reference Aflibercept for Patients with Neovascular Age-Related Macular Degeneration: A Randomized Phase 3 Trial.

INTRODUCTION: This trial aimed to compare the efficacy and safety between biosimilar QL1207 and the reference aflibercept for the treatment of neovascular age-related macular degeneration (nAMD). METHODS: This randomized, double-blind, phase 3 trial was conducted at 35 centers in China. Patients aged ≥ 50 years old with untreated subfoveal choroidal neovascularization secondary to nAMD and best-corrected visual acuity (BCVA) letter score of 73-34 were eligible. Patients were randomly assigned to receive intravitreous injections of QL1207 or aflibercept 2 mg (0.05 ml) in the study eye every 4 weeks for the first 3 months, followed by 2 mg every 8 weeks until week 48, stratified by baseline BCVA ≥ or < 45 letters. The primary endpoint was BCVA change from baseline at week 12. The equivalence margin was ± 5 letters. The safety, immunogenicity, pharmacokinetics (PK), and plasma vascular endothelial growth factor (VEGF) concentration were also evaluated. RESULTS: A total of 366 patients were enrolled (QL1207 group, n = 185; aflibercept group, n = 181) from Aug 2019 to Jan 2022 with comparable baseline characteristics. The least-squares mean difference in BCVA changes was - 1.1 letters (95% confidence interval - 3.0 to 0.7; P = 0.2275) between the two groups, within the equivalence margin. The incidences of treatment-emergent adverse events (TEAE; QL1207: 71.4% [132/185] vs. aflibercept: 71.8% [130/181]) and serious TEAE (QL1207: 14.1% [26] vs. aflibercept: 12.7% [23]) appeared comparable between treatment groups, and no new safety signal was found. Anti-drug antibody, PK profiles, and VEGF concentration were similar between the two groups. CONCLUSIONS: QL1207 has equivalent efficacy to aflibercept for nAMD with similar safety profiles. It could be used as an alternative anti-VEGF agent for clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05345236 (retrospectively registered on April 25, 2022); National Medical Products Administration of China: CTR20190937 (May 20, 2019).

Safety profile of 0.0015% tafluprost eye drops in China: a post-marketing observational study.

AIM: To investigate the treatment pattern and safety of tafluprost for glaucoma and ocular hypertension (OH) in clinical practice in China. METHODS: This post-marketing observational study included patients who received tafluprost to lower intraocular pressure (IOP) within 30d between September 2017 and March 2020 in 20 hospitals in China. Adverse drug reactions (ADRs) during tafluprost treatment and within 30d after the treatment were collected. RESULTS: A total of 2544 patients were included in this study, of them 58.5% (1488/2544) had primary open angle glaucoma (POAG), 21.9% (556/2544) had OH and 19.7% (500/2544) used tafluprost for other reasons. Of 359 ADRs occurred in 10.1% (258/2544) patients, and no serious adverse event occurred. The most common ADR was conjunctival hyperemia (128 ADRs in 124 patients, 4.9%). Totally 1670 participants (65.6%) combined tafluprost with carbonic anhydrase inhibitors (CAIs; 37.1%, 620/1670), sympathomimetics (33.5%, 559/1670), ß-blockers (33.2%, 555/1670), other prostaglandin analogs (PGAs; 15.6%, 260/1670) and other eye drops (15.1%, 253/1670). The highest incidence of conjunctival hyperemia was noted in patients who received tafluprost in combination with other PGAs (23 ADRs in 23 patients, 8.8%, 23/260) and the lowest was in combination with CAIs (16 ADRs in 16 patients, 2.6%, 16/620). Tafluprost was applied in primary angle-closure glaucoma (41.6%, 208/500), after glaucoma surgery (17.8%, 89/500) and after non-glaucoma surgery (15.8%, 79/500). CONCLUSION: Tafluprost is safe for POAG and OH, and tolerable when combined with other eye drops and under various clinical circumstances.

Magnesium Depletion Score Predicts Diabetic Retinopathy Risk among Diabetes: Findings from NHANES 2005-2018.

Magnesium is essential for material and energy metabolism. The magnesium depletion score (MDS) is recognized as a more valuable and reliable predictor of body magnesium status than any other clinical used markers such as serum and urine magnesium. However, research on the relationship between MDS and diabetic retinopathy (DR) is limited. As a result, the current study sought to assess this issue in diabetic samples from a large population-based database in the United States. Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2005-2018. MDS was calculated, and multivariate logistic regression analysis was applied to evaluate the presence of association between variables and DR risk. A total of 4308 participants was comprised in this study. Samples with DR consumed less magnesium (259.1 ± 113.6 vs 269.8 ± 113.2 mg, P < 0.001), and their MDS levels differed significantly from non-DR participants (P < 0.001). Increased dietary magnesium was linked to a lower incidence of DR (all P for trend < 0.05), and patients with a high level of MDS were more prone to DR (P = 0.001). Furthermore, subgroup analysis revealed that high (Q3) amount magnesium supplements was associated with lower DR risk when MDS was none to low or middle level (both P = 0.02). Our results indicated that MDS levels are associated with DR risk and that magnesium supplementation is benefit to DR prevention.

Cyclosporine A (0.05%) Ophthalmic Gel in the Treatment of Dry Eye Disease: A Multicenter, Randomized, Double-Masked, Phase III, COSMO Trial.

Purpose: To confirm the efficacy and safety of a novel ophthalmic cyclosporine A gel (CyclAGel, 0.05% CsA) in treating patients with moderate-to-severe dry eye disease (DED). Patients and Methods: The COSMO trial was a randomized, multicenter, double-masked, vehicle-controlled, phase III trial. Patients with moderate-to-severe DED were enrolled in 37 hospitals in China between November 2020 and April 2021. Eligible patients were randomized 1:1 to receive CyclAGel 0.05% or vehicle eye drops once nightly (QD). The primary endpoint was the proportion of subjects with at least a 1-point improvement in ICSS at day 84. Treatment-emergent adverse events (TEAEs) were recorded. Results: The full analysis set (FAS) included 315 and 312 participants in the CyclAGel and vehicle groups, respectively. The primary efficacy endpoint was achieved. The proportion of subjects with at least a 1-point improvement in ICSS from baseline to day 84 was significantly higher in the CyclAGel group than in the vehicle group (73.7% [232/315] vs 53.2% [166/312], P<0.0001). Significant improvements relative to the vehicle were also observed in the ICSS and Oxford scale scoring of corneal and conjunctival fluorescein staining at day 14, 42, and 84. The Schirmer tear test results were significantly higher in the CyclAGel group than in the vehicle group on days 14 and 84 (all P<0.05). The CyclAGel 0.05% was well tolerated, and the TEAEs were mostly mild. The most frequent treatment-related TEAE was eye pain (6.9% vs 1.6% in the CyclAGel and vehicle groups, respectively). No serious treatment-related TEAEs were reported. Conclusion: Clinically and statistically significant improvements in ICSS, tear production, and symptoms were observed in participants administered CyclAGel 0.05% QD for moderate-to-severe DED. CyclAGel 0.05% QD is a new effective, safe, and well-tolerated therapeutic option that might bring additional benefits of convenience and compliance as a once-A-day treatment for DED.

Endovascular Hyaluronidase Application Through Superselective Angiography to Rescue Blindness Caused by Hyaluronic Acid Injection.

BACKGROUND: Blindness is a rare but catastrophic complication of facial hyaluronic acid (HA) injection. Although various means to rescue visual impairment have been employed, no consensus regarding effective treatment has yet been reached. We organized a multidisciplinary team to address this emergency situation by means of endovascular hyaluronidase application. OBJECTIVES: The aim of this study was to investigate the direct delivery of hyaluronidase to ophthalmic artery occlusion through endovascular cannulation to resolve HA-induced blindness. METHODS: Four patients with visual impairments caused by HA filler embolization were subjected to sequential treatments. Through superselective angiography, a microcatheter was introduced along a guidewire from the femoral artery to the ophthalmic artery to directly deliver hyaluronidase to the HA embolism. The safety and efficiency of this treatment were systematically analyzed. RESULTS: Selective cerebral angiography demonstrated that the endovascular application of hyaluronidase significantly alleviated occlusion in 3 patients. One patient showed slight visual improvement, whereas the other patients showed no improvement in their visual function during a follow-up period of more than 3 months. One patient suffered from cerebral infarction in the left middle cerebral artery during the intervention surgery. Moreover, 2 patients showed multiple lacunar cerebral infarctions after the operation, whereas none exhibited symptoms of hemiplegia during follow-up. CONCLUSIONS: Although the endovascular application of hyaluronidase could partially recanalize the occluded branches of the ophthalmic artery, it had limited effects on restoring vision. Considering the risks of vascular intervention surgery, this approach should be considered with caution.

Comparative effects of commonly used intraocular dyes on the viability of human retina Müller cells.

This study investigated the in vitro effect of various vital dyes in common clinical use on human Müller cell viability, and it compared the toxicity of these dyes using a cell culture model. Müller cells were exposed to a series of concentrations (1 %, 0.5 %, 0.25 %, and 0.125 % or 12.9 mM, 6.45 mM, 3.22 mM and 1.61 mM) of Indocyanine green (ICG) for 2, 24, 48, and 72 h. Similarly, groups of Müller cells were stained with "Heavy" brilliant blue G (HBBG), Trypan blue (TB) (0.15 %, or 1.56 mM), Membrane-blue-dual (MBD), and ICG (0.25 %, or 3.22 mM) or BBG (0.025 %, or 0.3 mM) with glucose (GS) (50 %, 66 % and 75 % or 2.78 M, 3.67 M and 4.17 M) for 30, 60, and 120 s. Cell viability was measured with the Cell Counting Kit-8 (CCK-8) and Lactate Dehydrogenase (LDH) release assays. We found that high stain concentration and long exposure time resulted in increased toxicity to Müller cells. Nevertheless, ICG seemed to be safe at the clinically relevant concentration of 0.25 % (3.22 mM) in the short time of exposure. TB was safer than both HBBG and MBD, especially HBBG. Hypertonic GS as a dilution was not safe for Müller cells, and the negative effect was more obvious in 0.025 % (0.3 mM) BBG than that in 0.25 % (3.22 mM) ICG. This is the first report to observe the cytotoxicity of commonly used stains in clinical on human Müller cells in vitro, and to provide some basis for further studies, including in vivo investigation.

Comparative efficacy evaluation of inverted internal limiting membrane flap technique and internal limiting membrane peeling in large macular holes: a systematic review and meta-analysis.

BACKGROUND: The purpose of this study was to compare the anatomical and visual outcomes of inverted internal limiting membrane (ILM) flap technique and internal limiting membrane peeling in large macular holes (MH). METHODS: Related studies were reviewed by searching electronic databases of Pubmed, Embase, Cochrane Library. We searched for articles that compared inverted ILM flap technique with ILM peeling for large MH (> 400 µm). Double-arm meta-analysis was performed for the primary end point that was the rate of MH closure, and the secondary end point was postoperative visual acuity (VA). Heterogeneity, publication bias, sensitivity analysis and subgroup analysis were conducted to guarantee the statistical power. RESULTS: This review included eight studies involving 593 eyes, 4 randomized control trials and 4 retrospective studies. After sensitivity analysis for eliminating the heterogeneity of primary outcome, the pooled data showed the rate of MH closure with inverted ILM flap technique group was statistically significantly higher than ILM peeling group (odds ratio (OR) = 3.95, 95% confidence interval (CI) = 1.89 to 8.27; P = 0.0003). At the follow-up duration of 3 months, postoperative VA was significantly better in the group of inverted ILM flap than ILM peeling (mean difference (MD) = - 0.16, 95% CI = - 0.23 to 0.09; P < 0.00001). However, there was no difference in visual outcomes between the two groups of different surgical treatments at relatively long-term follow-up over 6 months (MD = 0.01, 95% CI = - 0.12 to 0.15; P = 0.86). CONCLUSION: Vitrectomy with inverted ILM flap technique had a better anatomical outcome than ILM peeling. Flap technique also had a signifcant visual gain in the short term, but the limitations in visual recovery at a longer follow-up was found.

Internal limiting membrane insertion technique combined with nerve growth factor injection for large macular hole.

BACKGROUND: The study was proposed to determine whether nerve growth factor (NGF) combined with an internal limiting membrane (ILM) insertion was effective in the large idiopathic full-thickness macular hole (iFTMH) therapy. METHODS: A subset of 18 eyes (July 2015-October 2017) diagnosed as the large iFTMH were enrolled in this study. The subjects were treated using ILM insertion technique alone (ILM group) or ILM combined with NGF injection (NGF group) and the follow-up period was 6 months. Macular hole closure rates, best-corrected visual acuity (BCVA, improvements using ETDRS), and optical coherence tomography (OCT) findings were analyzed at 1st, 3rd, and 6th months postoperatively. RESULTS: We found that macular holes in both groups fully closed. In comparison to ILM insertion group, the NGF group had better BCVA at the 3rd month (48.00 ± 2.392 vs 58.22 ± 2.957, 95% confidence interval (CI): 2.159 to 18.29). The mean external limiting membrane (ELM, 422.2 ± 96 vs 674.9 ± 103.6, 95% CI: - 47.26 to 552.8) and ellipsoid zone (EZ, 496.7 ± 101.6 vs 766.7 ± 111.8, 95% CI: - 50.29 to 590.4) defects were significantly smaller in the NGF group at the 6th month in the follow-up examination. Complete recovery of ELM and EZ was observed in the NGF group in one eye of a patient and two eyes of two patients, respectively. In comparison, one eye's ELM and another eye's EZ were completely recovered in the ILM insertion group. CONCLUSION: Our results indicated that ILM insertion with NGF injection might be an effective technique for the initial surgical treatment of eyes with large MHs. The proposed approach yielded better recovery of the photoreceptor layers and consequently might have superior postoperative visual acuity. TRIAL REGISTRATION: chiCTR1900021711. Retrospectively registered 5 March 2019.

Nerve growth factor promotes the proliferation of Müller cells co-cultured with internal limiting membrane by regulating cell cycle via Trk-A/PI3K/Akt pathway.

BACKGROUND: Nerve growth factor (NGF), produced by Müller cells, and internal limiting membrane (ILM) have fundamental roles in the development of full-thickness macular hole (FTMH). However, the potential crosstalk between NGF and ILM in FTMH is unclear. This study aimed to explore the mechanism and effects of NGF on the proliferation of Müller cells co-cultured with ILM. METHODS: Primary Müller cells and ILM from New Zealand rabbits were extracted and authenticated with specific staining. Müller cells co-cultured with or without ILM were exposed to NGF and then analysed. Müller cell viability was estimated using cell counting kit-8. Cell cycle analysis was performed by flow cytometry. The levels of cell cycle-related gene were detected using qRT-PCR. The TrK-A/Akt signal axis and downstream signaling cascades such as p21, CyclinE, CDK2, CyclinD1, and CDK4 were investigated by western blotting. RESULTS: ILM treatment alone induced the proliferation of Müller cells following the promotion of phosphorylated Akt, while growth of Müller cells was enhanced by activation of the Trk-A/Akt pathway under the stimulation of NGF or NGF + ILM. Additionally, the ratio of S-phase cells was increased, while G2-phase cells decreased upon the treatment with either ILM or NGF alone, or with NGF + ILM co-treatment. Cell cycle-related genes such as CyclinD1, CyclinE, CDK2, and CDK4 were all upregulated, but p21 expression was downregulated in the presence of NGF, ILM, or NGF + ILM. There was an additive effect on cell proliferation and cell cycle in the group of Müller cells exposed to NGF co-cultured with ILM compared with either NGF or ILM treatment alone. However, both K252ɑ (inhibitors of Trk-A) and LY294002 (inhibitor for Akt) counteracted the effect of NGF or NGF + ILM on the protein levels of Trk-A, Akt, CyclinD1, CyclinE, CDK2, and p21. CONCLUSIONS: Müller cells co-cultured with ILM or NGF promoted cell proliferation by regulating cell cycle-correlated proteins via the PI3K/Akt pathway. ILM + NGF further amplified the PI3K/Akt signaling pathway by binding to Trk-A, leading to more cell growth. This study provides new insight into the potential mechanism of NGF-mediated proliferation of Müller cells co-cultured with or without ILM, which may have considerable impact on therapies for FTMH.

Transdifferentiation effects and related mechanisms of nerve growth factor and internal limiting membrane on Müller cells.

In this study, we investigated the pro-proliferative, pro-transdifferentiation effects and mechanisms of nerve growth factor (NGF), internal limiting membrane (ILM), and NGF+ILM on Müller cells. The Müller cells cultured with NGF, ILM or both were mediated with tyrosine kinase A (TrkA) (a high affinity receptor for NGF) inhibitor, phosphatidylinositol 3 kinase (PI3K)/protein kinase B (Akt) (an intracellular signaling pathway important in regulating the cell cycle) inhibitor, or LIN28 (a RNA-binding protein and a posttranscriptional regulator of genes involved in developmental timing and self-renewal in embryonic stem cells) siRNA. Immunofluorescence (IF), western blotting (WB) and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to detect the expression of related genes. As a result, NGF, ILM and NGF+ILM promoted cell proliferation, increased the ratio of 5-bromo-2-deoxyuridine (BrdU)-positive cells, and were correlated with TrkA and PI3K/Akt signaling. NGF alone promoted cell dedifferentiation and redifferentiation mainly towards neurons rather than towards glial cells, related to TrkA and PI3K/Akt signals. The expression of p-Akt and cyclinD1 was increased by the intervention of NGF, ILM or NGF+ILM via TrkA and PI3K/Akt signals. NGF alone promoted the expression of paired box 6 (PAX6) (a transcription factor present during embryonic development), sex-determining region Y-box 2 (SOX2) (a transcription factor essential for the self-renewal, or pluripotency, of undifferentiated embryonic stem cells) and LIN28, and inhibited the expression of lethal-7 (Let-7b), Let-7d, Let-7i and miR-98 (microRNAs, key developmental regulators). The expression of Achaete-scute homolog 1 (Ascl1, also called MASH1) (a neurodevelopmental gene) and endogenous NGF (closely related to neurogenesis) was also promoted by exogenous NGF and related to TrkA and PI3K/Akt signaling. The down-regulation of LIN28 significantly antagonized the effects of NGF on the transdifferentiation of Müller cells. Over all, our results showed that NGF promoted the proliferation and transdifferentiation of Müller cells towards photoreceptor neurons--not towards glial cells, which was related to the LIN28/Let-7 pathway through TrkA and PI3K/Akt signals. Additionally, ILM promoted Müller cells to enter the cell cycle and enhanced cell proliferation, since NGF+ILM promoted the proliferation of Müller cell more significantly than NGF alone.

Riboflavin and ultraviolet A irradiation for the prevention of progressive myopia in a guinea pig model.

In this study, we evaluated the effect of oral administration of riboflavin combined with whole-body ultraviolet A (UVA) irradiation on the biochemical and biomechanical properties of sclera in a guinea pig model to control the progression of myopia. Experimental groups were administered 0.1% riboflavin solution with or without vitamin C by gavage from 3 days before myopic modeling and during the modeling process. Guinea pigs underwent 30 min of whole-body UVA irradiation after each gavage for 2 weeks. For control groups, guinea pigs were administered vitamin C and underwent either whole-body UVA irradiation without 0.1% riboflavin solution or whole-body fluorescent lamp irradiation with or without 0.1% riboflavin solution. Resultantly, myopia models were established with an increased axial length and myopic diopter. Compared with myopic eyes in the control groups, the net increase in axial length, diopter and strain assessment decreased significantly, and the net decrease in sclera thickness, ultimate load, and stress assessment decreased significantly in experimental groups. MMP-2 expression showed a lower net increase, while TIMP-2 expression showed a lower net decrease. In addition, hyperplasia of scleral fibroblasts was more active in myopic eyes of experimental groups. Overall, our results showed that oral administration of riboflavin with whole-body UVA irradiation could increase the strength and stiffness of sclera by altering the biochemical and biomechanical properties, and decreases in axial elongation and myopic diopter are greater in the guinea pig myopic model.

Binocular indirect ophthalmo microscope-assistant gas-perfused pars plana vitrectomy: A novel technique for vitreous sample acquisition.

The vitreous sample has been used for the diagnosis of uveitis and intraocular malignancy for decades. The sample volume is usually limited to 1 mL with current techniques. In the present study, a novel technique for higher amount of vitreous sample acquisition, that is, Binocular Indirect Ophthalmo Microscope-assistant gas-perfused pars plana vitrectomy (BAG-PPV) was invented.For diagnostic purpose, BAG-PPV with 23-ga vitrectomy system was performed on a 54-year-old Chinese male with the symptom of bilateral atypical uveitis. More than 3 mL of vitreous sample per eye was collected without any significant complications. Cytopathology was confirmed on the basis of cell surface markers and released cytokines by flow cytometry analysis and cytokine assays respectively.A monoclonal B-cell population with the pattern of CD5, CD10, cyKi67, CD71, FMC7, CD23, and kappa light chain single expression for the right eye and a monoclonal B-cell pattern with CD5, CD10, cyKi67, and kappa light chain restriction for the left eye were identified. The cytokine assay revealed high levels of interleukin (IL)-10 (90,838.30 and 41,098.0 pg/mL for the right and left eyes, respectively) and IL10/IL6 ratios for both eyes (with 90.78 and 63.26 for the IL10/IL6 ratios of the right and left eyes, respectively), while those for the cerebrospinal fluid were low (4.77 pg/mL for the IL10 level and 0.65 for the IL10/IL6 ratio). Based on the results, the patient was diagnosed with primary intraocular lymphoma for bilateral eyes.Our results demonstrated that diagnostic vitrectomy with BAG-PPV using the 23-ga vitrectomy system was safe, efficient, and able to provide useful diagnostic information for suspicious intraocular malignancy and other atypical uveitis.

23-Gauge vitrectomy with external drainage therapy as a novel procedure to displace massive submacular hemorrhage secondary to polypoidal choroidal vasculopathy.

INTRODUCTION: Massive subretinal hemorrhage (SRH) due to polypoidal choroidal vasculopathy (PCV) remains a challenging field and the best treatment is still not certain. In the present study, we performed a novel surgical method which combined 23-gauge vitrectomy with external drainage therapy for displace massive SRH secondary to PCV. METHODS: From April 2015 to July 2015, 4 consecutive patients with massive SRH secondary to PCV received 23-gauge transconjunctival sutureless vitrectomy with external drainage therapy. Massive SRH was drained by scleral tunnel which was created using 30-gauge ultrathin needles during vitrectomy. We assessed the feasibility and safety of this procedure by analyzing best-corrected vision acuity (BCVA), central foveal thickness (CFT), and complication. RESULTS: Four patients had a mean age of 63.8 ±â€Š6.4 years (range: 59-73 years). The average interval between onset of symptoms of SRH and surgery was 23.8 ±â€Š11.1 days (range: 10-35 days). Mean follow-up duration was 7.0 ±â€Š0.8 months. All patients completed 6 months follow-up. Mean BCVA gradually improved during the follow-up period. At 6 months after treatment, mean BCVA was significantly improved in comparison to preoperative findings (P = 0.043, paired t test). One month after treatment, mean CFT was significantly thinner than baseline (P = 0.002, paired t test). No serious ocular or systemic adverse events were observed to be associated with combination of 23-gauge vitrectomy with external drainage therapy during the 6 months follow-up period. CONCLUSIONS: Our results show that a combination of 23-gauge vitrectomy with external drainage therapy is a novel effective and safe procedure that may be a good alternative for massive SRH due to PCV.

Dynamic changes of ocular biometric parameters: a modified form-deprivation myopia model of young guinea pigs.

AIM: To evaluate the dynamic ocular biometric changes of a modified form-deprivation myopia model in young guinea pigs. METHODS: THE ANIMALS WERE RANDOMLY ASSIGNED TO TWO GROUPS: the monocularly deprived facemask group (MDF, with all the right eyes covered, n=24) and the normal control group (free of facemask, n=24). Each group was then equally divided into four subgroups which were followed up for 2, 4, 6 and 8 weeks, respectively. Parameters measured from every eye included refraction, corneal curvature, axial length and the dry weight of sclera at the posterior pole. RESULTS: All the facemasks remained in place during the follow-up. The covered eyes developed myopia with the vitreous chamber lengthening and the dry weight of posterior sclera reduced at each time point compared with the contralateral uncovered (P<0.05 at all time points). The changes had a linear correlation with the deprivation time (P<0.05). There were no significant differences in all the parameters between the uncovered eyes of MDF group and the normal control group (P>0.05 at all time points). CONCLUSION: Monocular form deprivation with the facemask is highly effective and non-invasive in inducing axial myopia in guinea pigs. The axial myopia is mainly caused by the increased vitreous chamber length and the weakened posterior sclera rigidity. The form-deprivation eye didn't interfere with the natural development of the contralateral eye.

The toxic effect of different concentrations of povidone iodine on the rabbit's cornea.

OBJECTIVES: To investigate the effects of polyvinylpyrrolidone (i.e., povidone) iodine (PVP-I) in different concentrations on the rabbit's cornea. METHODS: PVP-I in various concentrations was instilled into the conjunctival sac and injected into the anterior chamber independently. The toxicity to the cornea was assessed by fluorescence dye, specular microscopy, and corneal pachymetry. RESULTS: After conjunctival sac PVP-I instillation, severe epithelial damage was observed at the concentrations of 5.0% and 2.5%. After anterior chamber PVP-I injection, significant corneal edema was observed at the concentrations of 2.0% and 1.5%. CONCLUSIONS: It can be safe and feasible to use 0.5% or 1.0% concentrations of PVP-I in conjunctival sac instillation for preoperative antisepsis.

[Laparoscopic operations for benign ovarian cysts: report of 50 cases].

OBJECTIVE: To investigate the surgical indications and techniques of laparoscopic operation for benign ovarian cysts. METHODS: Fifty patients with benign ovarian cysts underwent laparoscopic operations of cyst decollement, ovariotomy and adnexectomy. RESULTS: There were 46 cases (92%) of decollement, 2 cases (4%) of adnexectomy and 3 cases (6%) of ovariotomy. The operation time was 30-120 min, and the intraoperative blood loss 20 ml. CONCLUSION: Laparoscopic operation of benign ovarian cysts has advantages of minimal invasive surgery.