Construction and validation of a neovascular glaucoma nomogram in patients with diabetic retinopathy after pars plana vitrectomy.

BACKGROUND: Neovascular glaucoma (NVG) is likely to occur after pars plana vitrectomy (PPV) for diabetic retinopathy (DR) in some patients, thus reducing the expected benefit. Understanding the risk factors for NVG occurrence and building effective risk prediction models are currently required for clinical research. AIM: To develop a visual risk profile model to explore factors influencing DR after surgery. METHODS: We retrospectively selected 151 patients with DR undergoing PPV. The patients were divided into the NVG (NVG occurrence) and No-NVG (No NVG occurrence) groups according to the occurrence of NVG within 6 months after surgery. Independent risk factors for postoperative NVG were screened by logistic regression. A nomogram prediction model was established using R software, and the model's prediction accuracy was verified internally and externally, involving the receiver operator characteristic curve and correction curve. RESULTS: After importing the data into a logistic regression model, we concluded that a posterior capsular defect, preoperative vascular endothelial growth factor ≥ 302.90 pg/mL, glycosylated hemoglobin ≥ 9.05%, aqueous fluid interleukin 6 (IL-6) ≥ 53.27 pg/mL, and aqueous fluid IL-10 ≥ 9.11 pg/mL were independent risk factors for postoperative NVG in patients with DR (P < 0.05). A nomogram model was established based on the aforementioned independent risk factors, and a computer simulation repeated sampling method was used to internally and externally verify the nomogram model. The area under the curve (AUC), sensitivity, and specificity of the model were 0.962 [95% confidence interval (95%CI): 0.932-0.991], 91.5%, and 82.3%, respectively. The AUC, sensitivity, and specificity of the external validation were 0.878 (95%CI: 0.746-0.982), 66.7%, and 95.7%, respectively. CONCLUSION: A nomogram constructed based on the risk factors for postoperative NVG in patients with DR has a high prediction accuracy. This study can help formulate relevant preventive and treatment measures.

Analysis of postoperative ocular surface changes and intervention effect after pars plana vitrectomy in meibomian gland dysfunction dry eye patients.

AIM: To observe ocular surface changes after phacovitrectomy in patients with mild to moderate meibomian gland dysfunction (MGD)-type dry eye and track clinical treatment response using a Keratograph 5M and a LipiView interferometer. METHODS: Forty cases were randomized into control group A and treatment group B; the latter received meibomian gland treatment 3d before phacovitrectomy and sodium hyaluronate before and after surgery. The average non-invasive tear film break-up time (NITBUTav), first non-invasive tear film break-up time (NITBUTf), non-invasive measured tear meniscus height (NTMH), meibomian gland loss (MGL), lipid layer thickness (LLT) and partial blink rate (PBR) were measured preoperatively and 1wk, 1 and 3mo postoperatively. RESULTS: The NITBUTav values of group A at 1wk (4.38±0.47), 1mo (6.76±0.70), and 3mo (7.25±0.68) were significantly lower than those of group B (7.45±0.78, 10.46±0.97, and 11.31±0.89; P=0.002, 0.004, and 0.001, respectively). The NTMH values of group B at 1wk (0.20±0.01) and 1mo (0.22±0.01) were markedly higher than those of group A (0.15±0.01 and 0.15±0.01; P=0.008 and P<0.001, respectively); however, there was no difference at 3mo. The LLT of group B at 3mo [91.5 (76.25-100.00)] significantly exceeded that of group A [65.00 (54.50-91.25), P=0.017]. No obvious intergroup difference was found in MGL or PBR (P>0.05). CONCLUSION: Mild to moderate MGD dry eye worsens in the short term after phacovitrectomy. Preoperative cleaning, hot compresses, and meibomian gland massage as well as preoperative and postoperative sodium hyaluronate promote the rapid recovery of tear film stability.

Negative effects of enlarging internal limiting membrane peeling for idiopathic macular hole surgery.

AIM: To observe the effects of the different extents of internal limiting membrane (ILM) peeling on the surgical success and anatomical and functional outcomes of idiopathic macular hole (IMH). METHODS: In this retrospective cohort study, 36 patients were reviewed and divided into two groups according to the extent of ILM peeling: group A (18 patients), with the peeling area within one-half of the optic disc macular distance as the radius; group B (18 patients), with the peeling area larger than that of group A but did not exceed the optic disc macular distance as the radius. The main outcomes included the best corrected visual acuity (BCVA), light-adaptive electroretinography, macular hole (MH) closure rate, central macular thickness (CMT), retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness [nine regions based on the Early Treatment of Diabetic Retinopathy Study (ETDRS) ring] before and 1, 3, and 6mo after surgery. RESULTS: The closure rate was 94.4% (17/18) both in groups A and B. The BCVA in both groups improved significantly compared with the preoperative values, but there was no difference between the two groups. The b-wave amplitude of the electroretinogram analysis was significantly improved in both groups compared to that of the preoperative period, with a greater increase in group A than in group B at 6mo (P=0.017). The CMT in both groups gradually decreased after surgery, and there was no difference between the two groups. The RNFL thickness of the temporal outer ring region in group B was significantly lower than that in group A at 3 and 6mo after surgery (P=0.010, 0.032). The GCC thickness of the temporal outer ring region in group B was significantly lower than that in group A at 6mo after surgery (P=0.038). CONCLUSION: Enlarging the extent of ILM peeling doesn't affect the IMH closure rate and visual acuity recovery, but the greater the extent of peeling, the greater the damage to the inner retinal structures.

Artificial intelligence can assist with diagnosing retinal vein occlusion.

AIM: To assist with retinal vein occlusion (RVO) screening, artificial intelligence (AI) methods based on deep learning (DL) have been developed to alleviate the pressure experienced by ophthalmologists and discover and treat RVO as early as possible. METHODS: A total of 8600 color fundus photographs (CFPs) were included for training, validation, and testing of disease recognition models and lesion segmentation models. Four disease recognition and four lesion segmentation models were established and compared. Finally, one disease recognition model and one lesion segmentation model were selected as superior. Additionally, 224 CFPs from 130 patients were included as an external test set to determine the abilities of the two selected models. RESULTS: Using the Inception-v3 model for disease identification, the mean sensitivity, specificity, and F1 for the three disease types and normal CFPs were 0.93, 0.99, and 0.95, respectively, and the mean area under the curve (AUC) was 0.99. Using the DeepLab-v3 model for lesion segmentation, the mean sensitivity, specificity, and F1 for four lesion types (abnormally dilated and tortuous blood vessels, cotton-wool spots, flame-shaped hemorrhages, and hard exudates) were 0.74, 0.97, and 0.83, respectively. CONCLUSION: DL models show good performance when recognizing RVO and identifying lesions using CFPs. Because of the increasing number of RVO patients and increasing demand for trained ophthalmologists, DL models will be helpful for diagnosing RVO early in life and reducing vision impairment.

Follistatin-like protein 1 functions as a potential target of gene therapy in proliferative diabetic retinopathy.

The degree of retinal fibrosis increased in proliferative diabetic retinopathy (PDR) patients after administration of anti-Vascular endothelial growth factor (VEGF) injections. Previous studies showed that the balance between connective tissue growth factor (CTGF) and VEGF plays an important role. Therefore, in a high-glucose state, an anti-VEGF and CTGFshRNA dual-target model was used to simulate clinical dual-target treatment in PDR patients, and RNA sequencing (RNA-Seq) technology was used for whole transcriptome sequencing. A hypoxia model was constructed to verify the sequencing results at the cellular level, and the vitreous humor and proliferative membranes were collected from patients for verification. All sequencing results included Follistatin-like protein 1 (FSTL1) and extracellular matrix (ECM) receptor pathway, indicated that anti-VEGF therapy may upregulate FSTL1 expression, while dual-target treatment downregulated FSTL1. Thus, we further studied the function of FSTL1 on the expression of VEGF and ECM factors by both overexpressing and silencing FSTL1. In conclusion, our results suggested that FSTL1 may be involved in the pathogenesis of PDR and is related to fibrosis caused by the anti-VEGF treatment, thus providing a potential target for gene therapy in PDR.

Refractive outcomes after vitrectomy combined with phacoemulsification of idiopathic macular holes.

AIM: To report the refractive outcomes after vitrectomy combined with phacoemulsification and intraocular lens (IOL) implantation (phaco-vitrectomy) in idiopathic macular holes (IMH). METHODS: A total of 56 eyes with IMH (IMH group) that underwent phaco-vitrectomy and 44 eyes with age-related cataract (ARC group) that underwent cataract surgery were retrospectively reviewed. The best corrective visual acuity (BCVA), predicted refractive error (PRE), actual refractive error (ARE), axial length (AL), were measured in both groups before and 6mo after operation. The power calculation of IOL and the predicted refractive error (PRE) were calculated according to the SRK/T formula. The difference of PRE and ARE between the two groups were compared and analyzed. RESULTS: In the IMH group, the diameters of macular holes were 271.73±75.85 µm, the closure rate was 100%. The pre- and post-operative BCVA were 0.80±0.35 and 0.40±0.35 logMAR. The PRE of A-ultrasound and IOL Master in the IMH group was -0.27±0.25 and 0.10±0.66 D. The postoperative mean absolute prediction error (MAE) was observed to be 0.58±0.65 and 0.53±0.37 D in the IOL Master and A-ultrasound (P=0.758). The PRE and ARE of the IMH group were 0.10±0.66 D and -0.19±0.64 D (P=0.102). The PRE and ARE of the ARC group was -0.43±0.95 and -0.31±0.93 D (P=0.383). The difference between PRE and ARE was -0.33±0.81 and 0.09±0.64 D in the IMH and ARC groups (P=0.021). The proportion of myopic shift was 67.9% in the IMH group and 27.3% in the ARC group (P=0.004). CONCLUSION: The myopic shift can be observed in patients with IMH after phaco-vitrectomy.

Incomplete fluid-air exchange technique for idiopathic macular hole surgery.

AIM: To explore an improved procedure involving incomplete fluid-air exchange for idiopathic macular hole (IMH), and the closure rate, visual function, and the visual field of macular holes (MHs) were evaluated. METHODS: This prospective randomized controlled study, included 40 eyes of 40 patients with IMH who were treated with pars plana vitrectomy and peeling of the internal limiting membrane. They were grouped by random digital table. Twenty-one eyes underwent incomplete fluid-air exchange (IFA) and 19 eyes underwent traditional complete fluid-air exchange (CFA) as the control group. Outcomes included best-corrected visual acuity (BCVA), intraocular pressure, and optical coherence tomography, light adaptive electroretinography, and visual field evaluations. RESULTS: All MHs <400 µm were successfully closed. BCVAs before and 6mo after surgery were 0.82±0.41 logMAR and 0.28±0.17 logMAR in IFA group and 0.86±0.34 logMAR and 0.34±0.23 logMAR in CFA group, respectively. The electroretinogram analysis of patients in IFA group revealed increases in b-wave amplitudes at 1, 3, and 6mo after surgery. Additionally, patients in IFA group showed an amplitude increase of 28.6% from baseline at 6mo (P<0.05), while no obvious improvements were noted in CFA group. Although there were no statistically significant improvements in either group, the IFA group showed a slight increase in mean sensitivity (P>0.05). CONCLUSION: IFA is a reliable method that offers comparable closure rate to CFA and facilitates improvements in visual function.

Research progress on the role of connective tissue growth factor in fibrosis of diabetic retinopathy.

Diabetic retinopathy (DR) is one of the most important types of diabetic microangiopathy, which is a specific change of fundus lesions and is one of the most serious complications of diabetes. When DR develops to proliferative DR, the main factors of decreasing vision, and even blindness, include retinal detachment and vitreous hemorrhage caused by contraction of blood vessels by fiber membrane. Recent studies reported that the formation of fiber vascular membrane is closely related to retinal fibrosis. The connective tissue growth factor (CTGF) is a cytokine that is closely related to DR fibrosis. However, its mechanism is poorly understood. This paper summarizes the recent studies about CTGF on DR fibrosis for a comprehensive understanding of the role and mechanism of CTGF in PDR.

Application of artificial intelligence in ophthalmology.

Artificial intelligence is a general term that means to accomplish a task mainly by a computer, with the least human beings participation, and it is widely accepted as the invention of robots. With the development of this new technology, artificial intelligence has been one of the most influential information technology revolutions. We searched these English-language studies relative to ophthalmology published on PubMed and Springer databases. The application of artificial intelligence in ophthalmology mainly concentrates on the diseases with a high incidence, such as diabetic retinopathy, age-related macular degeneration, glaucoma, retinopathy of prematurity, age-related or congenital cataract and few with retinal vein occlusion. According to the above studies, we conclude that the sensitivity of detection and accuracy for proliferative diabetic retinopathy ranged from 75% to 91.7%, for non-proliferative diabetic retinopathy ranged from 75% to 94.7%, for age-related macular degeneration it ranged from 75% to 100%, for retinopathy of prematurity ranged over 95%, for retinal vein occlusion just one study reported ranged over 97%, for glaucoma ranged 63.7% to 93.1%, and for cataract it achieved a more than 70% similarity against clinical grading.

A meta-analysis of the effect of a dexamethasone intravitreal implant versus intravitreal anti-vascular endothelial growth factor treatment for diabetic macular edema.

BACKGROUND: This meta-analysis evaluated the effectiveness and safety of dexamethasone (DEX) implant and intravitreal anti-vascular endothelial growth factor (VEGF) treatment for diabetic macular edema (DME). METHODS: The PubMed, Embase, clinicaltrials.gov website and Cochrane Library databases were comprehensively searched for studies comparing DEX implant with anti-VEGF in patients with DME. Best-corrected visual acuity (BCVA), central subfield thickness (CST) and adverse events were extracted from the final eligible studies. Review Manager (RevMan) 5.3 for Mac was used to analyze the data and GRADE profiler were used to access the quality of outcomes. RESULTS: Based on four randomized clinical trials assessing a total of 521 eyes, the DEX implant can achieve visual acuity improvement for DME at rates similar to those achieved via anti-VEGF treatment (mean difference [MD] = - 0.43, P = 0.35), with superior anatomic outcomes at 6 months (MD = - 86.71 µm, P = 0.02), while requiring fewer injections, in comparison to anti-VEGF treatment. Although the mean reduction in CST did not showed significant difference at 12 months (MD = - 33.77 µm, P = 0.21), the significant in BCVA from baseline to 12 months supported the anti-VEGF treatment (MD = - 3.26, P < 0.00001). No statistically significant differences in terms of the serious adverse events. However, use of the DEX implant has higher risk of intraocular pressure elevation and cataract than anti-VEGF treatment. CONCLUSIONS: Compared with anti-VEGF, DEX implant improved anatomical outcomes significantly. However, this did not translate to improved visual acuity, which may be due to the progression of cataract. Therefore, the DEX implant may be recommended as a first chioce for select cases, such as for pseudophakic eyes, anti-VEGF-resistant eyes, or patients reluctant to receive intravitreal injections frequently.

Surgical induced astigmatism correlated with corneal pachymetry and intraocular pressure: transconjunctival sutureless 23-gauge versus 20-gauge sutured vitrectomy in diabetes mellitus.

AIM: To determine the difference of surgical induced astigmatism between conventional 20-gauge sutured vitrectomy and 23-gauge transconjunctival sutureless vitrectomy, and the influence of corneal pachymetry and intraocular pressure (IOP) on surgical induced astigmatism in diabetic patients. METHODS: This retrospective, consecutive case series consisted of 40 eyes of 38 diabetic subjects who underwent either 20-gauge or 23-gauge vitrectomy. The corneal curvature and thickness were measured with Scheimpflug imaging before surgery and 1wk; 1, 3mo after surgery. We compared the surgical induced astigmatism (SIA) on the true net power in 23-gauge group with that in 20-gauge group. We determined the correlation between corneal thickness change ratio, IOP and SIA measured by Pentacam. RESULTS: The mean SIAs were 1.082±0.085 D (mean±SEM), 0.689±0.070 D and 0.459±0.063 D at postoperative 1wk; 1, 3mo respectively in diabetic subjects. The vitrectomy induced astigmatisms were declined significantly with time (F 2,36=33.629, P=0.000) postoperatively. The 23-gauge surgery group induced significantly less astigmatism than 20-gauge surgery group (F -1,37=11.046, P=0.020). Corneal thickness in diabetes elevated after surgery (F 3,78=10.532, P=0.000). The linear regression analysis at postoperatively 1wk went as: SIA=-4.519+4.931 change ratio (Port3) +0.026 IOP (R(2)=0.46, P=0.000), whereas the rate of corneal thickness change and IOP showed no correlation with the change of astigmatism at postoperatively 1 and 3mo. CONCLUSION: There are significant serial changes in both 20-gauge and 23-gauge group in diabetic subjects. 23-gauge induce less astigmatism than 20-gauge and become stable more rapidly than 20-gauge. The elevation of corneal thickness and IOP was associated with increased astigmatim at the early postoperative stage both in 23-gauge and 20-gauge surgery group.

Application of Lutein and Zeaxanthin in nonproliferative diabetic retinopathy.

AIM: To compare serum Lutein and Zeaxanthin (L/Z) concentrations between patients with nonproliferative diabetic retinopathy (NDR) and normal subjects, and to explore the effect of L/Z supplementation on serum L/Z level and visual function in NDR patients METHODS: SUBJECTS WERE DIVIDED INTO THREE GROUPS: 30 NDR patients supplied with Lutein 6mg/d and Zeaxanthin 0.5mg/d for three months (DR Group), 30 NDR patients without L/Z supplementation (DR Control Group) and 30 normal subjects (Control Group). Serum L/Z concentrations were measured by liquid high-resolution chromatography (HPLC). Visual acuity was recorded at baseline, 1 month, 2 months and 3 months post initial supplementation. Serum L/Z concentration were measured at baseline, 1 month and 2 months post initial supplementation. Contrast sensitivity (CS) and fovea thickness were recorded at baseline and 3 months post initial supplementation. RESULTS: Mean serum lutein concentrations in DR group were 0.0686±0.0296µg/mL and zeaxanthin concentration was 0.0137±0.0059µg/mL. The L/Z level of DR group was significantly lower compared to the control group (lutein: 0.2302±0.1308µg/mL, zeaxanthin: 0.0456±0.0266µg/m, P=0.000). The concentration of lutein and zeaxanthin in the DR control group at base line was 0.0714±0.0357µg/mL and 0.0119±0.0072µg/mL, respectively. There was no significant change of L/Z concentration in the DR control group during the study. Serum L/Z concentrations of DR group increased significantly after supplementation (F=109.124, P=0.000; F=219.207, P=0.000). Visual acuity improved significantly after medication. Compared with pre-medication, the average CS values of 1.5cpd, 3cpd and 6cpd after three months increased significantly (P=0.030,0.013,0.008) and the foveal thickness decreased. (P=0.05) CONCLUSION: Serum L/Z concentrations in DR patients are significantly lower than those in normal subjects, and L/Z intake can improve the visual acuity, CS and macular edema in DR patients, suggesting that L/Z supplementation might be targeted as potential potential therapeutic agents in treating NDR.

[Clinical research of accommodating intraocular lens].

OBJECTIVE: To assess the visual outcomes and accommodative amplitude of accommodating intraocular lens (AIOL). METHODS: Case control study. Thirty eyes of 22 patients with cataracts had undergone phacoemulsification and implantation of AIOL. Twenty nine eyes of 22 age- and sex-matched patients with cataracts had the same surgery but foldable acrylic IOL were used as the controls. All patients were assessed for accommodation amplitude, visual acuity and for change of anterior chamber depth (ACD) at 6 and 12 months after surgery. Accommodation amplitude was measured using the pushing-up test. The change of ACD was measured with OCULUS Pentacam analysis system. RESULTS: During the follow-up time, the patients in the test group had better uncorrected near vision acuity (UCNV) and distance corrected near vision acuity (DCNVA)(P = 0.000). The test group had the same corrected vision acuity as the control group. Six months after surgery, push-up test showed that the mean accommodative amplitude was (1.60 +/- 0.57) D in the test group and (1.10 +/- 0.70) D in the control group. The change of the ACD was (0.50 +/- 0.37) mm in the test group and (0.08 +/- 0.06) mm in the control group. Twelve months after surgery, push-up test showed that the mean accommodative amplitude was (1.38 +/- 0.52) D in the test group and (1.06 +/- 0.61) D in the control group. The change of the ACD was (0.30 +/- 0.27) mm in the test group and (0.10 +/- 0.09) mm in the control group. CONCLUSIONS: In the present study, the Tetraflex AIOL showed greater accommodative amplitude and better near visual acuity than those of the control group with conventional IOL. But 6 months later, all of these measurements in the test group were decreased.

[Early clinical study of bimanual microphacoemulsification with rollable intraocular lens].

OBJECTIVE: To analyze the results of bimanual microphacoemulsification combined with rollable intraocular lens (IOL), to evaluate the feasibility and safety of this procedure and to compare the clinical results of two different types of rollable intraocular lens. METHODS: Thirty-five cases (35 eyes) were divided into 2 groups. Group 1 included 15 eyes used Thinoptx IOL, Group 2 included 20 eyes used Acri. Smart IOL. The data included best corrected visual acuity (BCVA) and intraocular pressure (IOP) (pre-, 1 day, 1 week and 1 month post-operatively); corneal curvature (pre- and 1 month post-operatively); target refraction and post-operation refraction (1 month after the operation). RESULTS: A significant difference was found between pre-operative and 1 month post-operative BCVA (P<0.01). No significant different was found between pre-operative and post-operative IOP, astigmatism, target refraction and refraction. There was no significant difference in pre-operative and post-operative astigmatism, target refraction and post-operation 1-month refraction between these two groups. CONCLUSIONS: Bimanual microphacoemulsification with rollable intraocular lens (IOL) is a feasible and safe procedure for the cataract surgery.

[Intraocular lens power calculation in cataract phacoemulsification after refractive surgery].

OBJECTIVE: To analyze the results of phacoemulsification cataract surgery in eyes that had refractive surgery and to compare the predictability of K value in Holladay II formula of intraocular lens power calculation. METHODS: Fifteen cases (15 eyes) were divided into 2 groups. Group 1 included 8 eyes, the IOL power was calculated with Holladay II formula and the K value was calculated using surgeon-entered k-value (KS). Group 2 included 7 eyes, the IOL power was calculated with Holladay II formula also, the K value was calculated using k-value from refractive data (KR). The achieved refraction after phacoemulsification was compared with target refraction to assess the predictability of the formula and the accuracy of k-value. RESULTS: The mean difference between target and achieved refractions after phacoemulsification was (0.90 +/- 0.22) D in group 1 and (0.99 +/- 0.22) D in group 2. CONCLUSIONS: Holladay II formula is accurate in the IOL power calculation after refractive surgery. There is no significant difference between the results calculated by Holladay II formula with KS or KR.