A new segmentation algorithm for peripapillary atrophy and optic disk from ultra-widefield Photographs1.

BACKGROUND AND OBJECTIVE: The prevalence of myopia and high myopia is increasing globally, underscoring the growing importance of diagnosing high myopia-related pathologies. While existing image segmentation models, such as U-Net, UNet++, ResU-Net, and TransUNet, have achieved significant success in medical image segmentation, they still face challenges when dealing with ultra-widefield (UWF) fundus images. This study introduces a novel automatic segmentation algorithm for the optic disc and peripapillary atrophy (PPA) based on UWF fundus images, aimed at assisting ophthalmologists in more accurately diagnosing high myopia-related diseases. METHODS: In this study, we developed a segmentation model leveraging a Transformer-based network structure, complemented by atrous convolution and selective boundary aggregation modules, to elevate the accuracy of segmenting the optic disc and PPA in UWF photography. The atrous convolution module adeptly manages multi-scale features, catering to the variances in target sizes and expanding the deep network's receptive field. Concurrently, the incorporation of the selective boundary aggregation module in the skip connections of the model significantly improves the differentiation of boundary information between segmentation targets. Moreover, the comparison of our proposed algorithm with classical segmentation models like U-Net, UNet++, ResU-Net, and TransUNet highlights its considerable advantages in processing UWF photographs. RESULTS: The experimental results show that, compared to the other four models, our algorithm demonstrates substantial improvements in segmenting the optic disc and PPA in UWF photographs. In PPA segmentation, our algorithm improves by 0.8% in Dice, 1.8% in sensitivity, and 1.3% in intersection over union (IOU). In optic disc segmentation, our algorithm improves by 0.3% in Dice, 0.6% in precision, and 0.4% in IOU. CONCLUSION: Our proposed method improves the segmentation accuracy of PPA and optic disks based on UWF photographs, which is valuable for diagnosing high myopia-related diseases in ophthalmology clinics.

A20 functions as a negative regulator of the lipopolysaccharide-induced inflammation in corneal epithelial cells.

A20, also called TNFAIP3, is a crucial regulator of inflammation in various diseases but has not evidenced its function in the cornea. We aimed to evaluate the existence and the functions of A20 in human corneal epithelial (HCE-T) cells. After being treated with lipopolysaccharide (LPS) in different concentrations or at separate times, cells were collected to analyze A20 expressions. We then constructed the A20 knockdown system by siRNA and the A20 overexpressing system by lentivirus transduction. Systems were further exposed to medium with or without LPS for indicated times. Next, we evaluated the production of inflammatory cytokines (IL-6 and IL-8) by qRT-PCR and ELISA. Also, the translocation of P65 and the phosphorylation of P65, P38 and JNK were observed in two systems. In addition, we used the nuclear factor kappa-B (NF-κB) antagonist TPCA-1 for the pretreatment in cells and then detected the A20 expressions. We found a low basal expression of A20 in HCE-T cells, and the expressions could be dose-dependently induced by LPS, peaking at 4 h in protein level after stimulation. Both the A20 knockdown and A20 overexpressing systems were confirmed to be effective. After the LPS treatment, productions of IL-6 and IL-8 were enhanced in the A20 knockdown system and reduced in the A20 overexpressing system. A20 reduced the translocation of P65 into the nucleus and the phosphorylation of P65, P38 and JNK. Furthermore, TPCA-1 pretreatment reduced the expression of A20 in cells. We concluded that A20 is a potent regulator for corneal epithelium's reaction to inflammation, and it thus is expected to be a potential therapy target for ocular surface diseases.

Surgical Outcomes of Myopic Foveoschisis According to the ATN Classification System.

INTRODUCTION: This study compared the surgical outcomes in eyes with myopic foveoschisis (MF) according to the recently developed ATN classification system. METHODS: This was an observational case series of 64 consecutive eyes that underwent vitrectomy for MF. Eyes were classified into severe myopic maculopathy (MM) (n = 43) and non-severe MM (n = 21) groups according to the ATN classification system. The primary outcome measures constituted best-corrected visual acuity (BCVA) and anatomical changes. RESULTS: In total, BCVA improved from 0.97 to 0.53 (P < 0.001) after surgery. The ATN score was significantly lower in the eyes with vision improvement than those without vision improvement (P < 0.001). In the subgroup, BCVA improved from 0.79 to 0.28 in the non-severe MM group (P < 0.001), and improved from 1.05 to 0.65 in the severe MM group (P = 0.001) after surgery. The non-severe MM group achieved better postoperative BCVA (P = 0.001) and were more likely to gain vision improvement (P < 0.001) after surgery compared with the severe MM group. Anatomical success was achieved in 62 of the 64 eyes (96.88%). Two eyes with anatomical failure developed full-thickness macular holes postoperatively; both were in the severe MM group. CONCLUSIONS: For patients with MF, different severity of MM based on ATN classification could lead to a significantly different prognosis after surgery. For patients with high ATN scores, the operative decision should be made cautiously for the worse anatomical and visual prognosis. ATN system is instructive in making operative proposals for MF.

On the basis of the newly developed ATN classification system, we found significant differences in postoperative visual acuity, the rate of vision improvement, and the rate of primary retinal reattachment after vitrectomy between the severe and non-severe myopic maculopathy groups in patients with myopic foveoschisis.

Eliciting blinks by transcutaneous electric nerve stimulation improves tear fluid in healthy video display terminal users: A self-controlled study.

We aimed to elicit strong blinks among healthy video display terminal (VDT) users by periorbital transcutaneous electric nerve stimulation (TENS) and evaluate its impact on the tear fluid and visual task. Appropriate TENS conditions were evaluated to evoke strong blinks under minimum discomfort. Seventeen healthy VDT users with noninvasive Keratograph first breakup time (NIKf-BUT) 5-15 s and Ocular Surface Disease Index (OSDI) scores < 15 were recruited in this study. Before the trial, noninvasive Keratograph average breakup time (NIKa-BUT), tear meniscus height (TMH) and OSDI scores were evaluated. Before each TENS session, the volunteers played Tetris while the corresponding blink rate and Tetris scores were recorded. Then, the participants underwent 30 minutes of TENS, which evoked blinking of their right eye 20 times per minute. Tetris scores were evaluated again during TENS. The Tetris scores and corresponding blink rate were assessed after each TENS session while NIKa-BUT, TMH and OSDI scores were recorded after the third and sixth TENS sessions. We found that OSDI scores declined significantly after the sixth TENS (P = .003). The NIKa-BUT of the right eye was promoted after the sixth TENS (P = .02), and the TMH was higher after the third and sixth TENS in both eyes (P = .03, P = .03 for right eyes respectively, P = .01, P = .01 for left eyes respectively). There was no significant difference between the adjusted Tetris scores before and during TENS (P = .12). The blink rate before and after TENS were unaffected after 6 sessions (P = .61). The results indicated that periorbital TENS effectively ameliorated ocular irritation and improved tear secretion and tear film stability by eliciting strong blinks in healthy VDT users without disturbing the visual task.

Systematic bibliometric and visualized analysis of research hotspots and trends on the application of artificial intelligence in diabetic retinopathy.

Background: Artificial intelligence (AI), which has been used to diagnose diabetic retinopathy (DR), may impact future medical and ophthalmic practices. Therefore, this study explored AI's general applications and research frontiers in the detection and gradation of DR. Methods: Citation data were obtained from the Web of Science Core Collection database (WoSCC) to assess the application of AI in diagnosing DR in the literature published from January 1, 2012, to June 30, 2022. These data were processed by CiteSpace 6.1.R3 software. Results: Overall, 858 publications from 77 countries and regions were examined, with the United States considered the leading country in this domain. The largest cluster labeled "automated detection" was employed in the generating stage from 2007 to 2014. The burst keywords from 2020 to 2022 were artificial intelligence and transfer learning. Conclusion: Initial research focused on the study of intelligent algorithms used to localize or recognize lesions on fundus images to assist in diagnosing DR. Presently, the focus of research has changed from upgrading the accuracy and efficiency of DR lesion detection and classification to research on DR diagnostic systems. However, further studies on DR and computer engineering are required.

Agreement Between Predicted and Actual Measured Ablation Depth After FS-LASIK Using Different Rotating Scheimpflug Cameras and OCT.

Purpose: To compare the predicted ablation depth (AD) with the postoperatively measured corneal ablation depth (postop-AD) at central, paracentral, and midperipheral locations using two rotating Scheimpflug analyzers and a Fourier-domain optical coherence tomographer in eyes that underwent femtosecond laser-assisted LASIK (FS-LASIK). Methods: The values of corneal thickness were measured preoperatively and postoperatively at one and three months. The difference between preoperative and postoperative was defined as postop-AD. Measurements were performed at the corneal vertex and mid-peripheral area. The mid-peripheral corneal thickness was measured at the superior, inferior, nasal, and temporal locations at a distance of 1.0 or 2.5 mm from the corneal vertex. The predicted AD was calculated by ORK-CAM software (Schwind eye tech-solutions GmbH, Kleinostheim, Germany), and the difference between the predicted AD and postop-AD was defined as Δ-AD. Paired t-test analysis was employed to evaluate the differences, agreement was assessed by the Bland-Altman method. Results: Forty-two eyes of 42 patients were investigated. At one month, the predicted AD in the central and paracentral areas was underestimated by the Pentacam HR (Oculus, Wetzlar, Germany), Sirius (Costruzione Strumenti Oftalmici, Florence, Italy) and RTVue OCT (Optovue Inc., Freemont, CA, United States), whereas Δ-AD was negative as established by all devices and predominantly statistically significant. The Δ-AD values approximated zero at three months. The mean difference of Δ-AD at three months at the corneal vertex was 0.67 ± 9.39 mm, -7.92 ± 9.05 mm and -1.36 ± 8.31 mm, respectively. The mid-peripheral measurements had positive values at one month and even more highly positive at three months (with statistically significant differences in most of the cases). The agreement between the predicted and postop-AD was moderate with all devices, but slightly better with RTVue. Conclusion: The predicted AD seems to be underestimated in the central and paracentral corneal area and overestimated in the mid-periphery. Translational Relevance: The study could help to partly explain and prevent the refractive errors after FS-LASIK.

Recharacterization of superior limbic keratoconjunctivitis via a subdividing grading method in 236 Chinese patients.

PURPOSE: Superior limbic keratoconjunctivitis (SLK) is an uncommon and often overlooked chronic ocular surface disease. This retrospective consecutive case series study on Chinese patients aimed to characterize the features of this disease, including those undescribed in previous literature. METHODS: Two hundred thirty-six patients diagnosed with SLK were enrolled into this consecutive case study from 2016 to 2019. The demographics, symptoms, Ocular Surface Disease Index, and ocular signs were collected and analyzed. A scoring system (SLK scale index, SSI) that integrated five major sign scores was applied to evaluate SLK severity. RESULTS: Of the 236 SLK patients, dryness was the most common complaint (59.3%). Of 459 SLK eyes, superior limbus/conjunctival staining (SCS) was present in 98% eyes, followed by the superior tarsal conjunctival alterations (85.2%) and superior bulbar conjunctiva hyperemia (80.8%). Approximately 63% of eyes were accompanied by corneal staining. Superior bulbar conjunctivochalasis was a relatively rare sign (41.6%). Among the five major signs, only the prevalence of SCS gradually increased with its severity. In addition, fluorescein staining at the inferior limbus and adjacent conjunctiva (ICS) was found positive in 163 eyes of 84 patients (36%) who had significantly higher SSI than those without ICS (p = 0.013). CONCLUSIONS: We found that SCS is the most common out of the 5 typical signs of SLK. ICS, a new sign, occurred in one-third of patients. SCS, a simple marker of SLK, as well as SSI, an integrated evaluation system, had the advantage of evaluating the severity and objectively characterizing SLK in clinical practice.

Advances in artificial intelligence applications for ocular surface diseases diagnosis.

In recent years, with the rapid development of computer technology, continual optimization of various learning algorithms and architectures, and establishment of numerous large databases, artificial intelligence (AI) has been unprecedentedly developed and applied in the field of ophthalmology. In the past, ophthalmological AI research mainly focused on posterior segment diseases, such as diabetic retinopathy, retinopathy of prematurity, age-related macular degeneration, retinal vein occlusion, and glaucoma optic neuropathy. Meanwhile, an increasing number of studies have employed AI to diagnose ocular surface diseases. In this review, we summarize the research progress of AI in the diagnosis of several ocular surface diseases, namely keratitis, keratoconus, dry eye, and pterygium. We discuss the limitations and challenges of AI in the diagnosis of ocular surface diseases, as well as prospects for the future.

Vitreomacular Interface Abnormalities in Myopic Foveoschisis: Correlation With Morphological Features and Outcome of Vitrectomy.

Purpose: To compare the morphologic characteristics and response to surgery of myopic foveoschisis (MF) with different patterns of vitreomacular interface abnormalities (VMIAs). Methods: In this observational case series, 158 eyes of 121 MF patients with epiretinal membrane (ERM) or vitreomacular traction (VMT) based on optical coherence tomography (OCT) were enrolled. All the eyes were divided into two groups by the pattern of VMIAs: ERM and VMT group. Sixty-one eyes underwent pars plana vitrectomy (PPV) and were followed up for at least 6 months. The morphologic characteristics based on OCT and the surgical outcome were evaluated. Outcome: ERM and VMT were found in 47.47 and 52.53% of the cases, respectively. A higher rate of foveal detachment (61.4 vs. 26.7%; p < 0.001) and a higher rate of outer lamellar macular hole (45.8 vs. 21.3%; p = 0.001) were detected in the eyes with VMT compared with those with ERM. In contrast, a lower rate of inner lamellar macular hole (28.9 vs. 60.0%; p = 0.001) was detected in the eyes with VMT compared with those with ERM. The disruption of the external limiting membrane (ELM) was more common in the eyes with VMT than in those with ERM (45.8 vs. 21.3%; p = 0.001). PPV was performed in 61 eyes with a mean follow-up time of 23.55 ± 19.92 months. After surgery, anatomical resolution was achieved in 51 eyes (83.6%). At the final visit, the mean central foveal thickness (CFT) decreased significantly from 547.83 to 118.74 µm, and the mean LogMAR BCVA improved significantly from 0.92 to 0.57. The VMT group was associated with a higher proportion of eyes with visual acuity improvement postoperatively (p = 0.02) and had more a decrease of CFT (P = 0.007) compared with the ERM group. Conclusion: In the eyes with MF, outer retinal lesions occurred more frequently in the eyes with VMT, whereas inner retinal lesions occurred more frequently in the eyes with ERM. Tangential force generated by ERM may act as a causative factor for the inner retinal lesions in MF, and inward-directed force resulting from VMT may act as a causative factor for outer retinal lesions in MF.

Metabolomic Alterations in the Tear Fluids of Patients With Superior Limbic Keratoconjunctivitis.

PURPOSE: Superior limbic keratoconjunctivitis (SLK) is a bilateral, chronic inflammatory disease that recurs for up to several years; however, the fundamental processes involved in its pathogenic mechanisms remain unknown. We aimed to investigate the metabolomic alterations in the tear fluids of patients with superior limbic keratoconjunctivitis (SLK) compared with those of healthy volunteers (Ctrl group). METHODS: We performed a cross-sectional study involving 42 subjects. Tear fluid was taken from one eye of 24 SLK patients (40.13 ± 14.55 years, 83.33% female) and 18 healthy volunteers (Ctrl, 39.89 ± 9.2 years, 72.22% female) using Schirmer strips. After the liquid extraction of tear metabolites, samples were infused into the QE HFX Orbitrap mass spectrometer in both positive and negative ion mode. Metabolites were quantitatively analyzed and matched with entries in the HMDB database. Metabolic differences between the SLK group and the control group were identified based on multivariate statistical analysis. Open database sources, including SMPDB and MetaboAnalyst, were used to identify metabolic pathways. RESULTS: Among 179 metabolites retained for annotation, 133 metabolites were finally identified, among which 50 were found to be significantly changed in SLK patients. Of these 50 metabolites, 31 metabolites significantly increased and 19 metabolites decreased in SLK patients. The altered metabolites are mainly involved in α linolenic acid and linoleic acid metabolism, ketone body metabolism, butyrate metabolism, mitochondrial electron transport chain, carnitine synthesis, and so on. The most significantly changed pathway was linoleic acid metabolism. To explore the utility of tear biomarkers, a model combining 9 metabolites (phenol, ethyl glucuronide, eicosapentaenoic acid, 12-keto-leukotriene B4, linoleic acid, hypoxanthine, triethanolamine, 1-nitrohexane, and terephthalic acid) was selected as a candidate biomarker. CONCLUSION: The results reveal that SLK has a specific metabolomic profile, of which some key elements can serve as potential biomarkers of SLK for diagnostic and prognostic purposes. The findings of this study are novel and provide a basis for further investigations of the mechanism of SLK.

Effects of fine particulate matter on the ocular surface: An in vitro and in vivo study.

Exposure to ambient fine particulate matter (fine PM) pollution has been previously associated with ocular surface diseases. But, to the best of our knowledge, the in vivo long-term effects of fine PM on the ocular surface have not been investigated. We aimed to evaluate the effects of fine PM on cultured human corneal epithelial (HCE) cells and on the ocular surfaces of mice, with standard reference material of fine PM(SRM 2786). We applied fine PM suspension to the eyes of C57BL/6 mice for up to 6 months. In vivo examinations, including tear secretion, tear film break-up time (TBUT) and corneal fluorescein staining, were performed in the 3rd and 6th month. At the end of the in vivo study, the corneal histological changes and conjunctival goblet cells were examined by staining, and cytokines in tissue were also detected. In addition, HCE cells were treated with fine PM for 12 h and 24 h. Then, cell apoptosis and reactive oxygen species (ROS) formation was detected. We found that fine PM damages the mouse eye in a dose- and time-dependent manner. In mice, the tear secretion and tear film break-up time were significantly reduced, along with the development of corneal epithelial damage, apoptosis of conjunctival epithelial cells and hypoplasia of conjunctival goblet cells. In addition, IL-18, IL-22, IL-23 and MCP-1 were increased in both conjunctiva and cornea of the fine PM-treated animals. Furthermore, increased apoptosis and ROS production were observed in time- and dose-dependent manner in HCE cells after fine PM exposure for 12 h and 24 h. Our results indicate that fine PM is cytotoxic to both HCE cells and the ocular surface. Long-term topical application of fine PM suspension in mice results in ocular surface changes that are similar to those observed with dry eye.