Vitamin D and tear fluid cytokines in predicting outcomes in viral conjunctivitis - A new outlook.

PURPOSE: To determine the association between systemic vitamin D (VD) and immunoglobulin E (IgE) levels with severity and ocular surface inflammatory profile in patients with epidemic keratoconjunctivitis (EKC). METHODS: 210 eyes of 105 patients who were clinically diagnosed with EKC were included in the study. The levels of serum VD and serum IgE were measured. Schirmer's strip-based tear fluid (TF) was used to determine levels of IL-1ß, IL-6, IL-10, IL-17A, TNFα, MMP9, sICAM1, and VEGF-A in a subset of patients. RESULTS: Levels of VD were significantly ( P < 0.05) lower and levels of IgE were significantly higher in patients with severe forms of conjunctivitis compared to those with nonsevere forms. Majority of the patients with severe forms of the disease exhibited VD deficiency and/or abnormally high IgE. A negative correlation (r = -0.682; P < 0.0001) was observed between VD and IgE levels. TF levels of IL-1ß, IL-6, TNFα, and sICAM1 were significantly higher in eyes with severe forms of conjunctivitis compared to those with nonsevere forms and controls. These factors showed a positive correlation ( P < 0.05) with IgE levels and a negative correlation ( P < 0.05) with VD levels. CONCLUSION: Patients with severe forms of EKC exhibited VD deficiency and higher levels of IgE. Increased TF inflammatory factors demonstrated a disease causal relationship with VD and IgE. Hence, restoring the altered levels of VD and IgE to normal range would be pivotal in the prevention and management of severe conjunctivitis.

Simultaneous Topography-guided Custom Ablation With Corneal Cross-linking for Keratoconus: 10-Year Prospective Outcomes.

PURPOSE: To assess 10-year visual and tomographic outcomes of topography-guided custom ablation (T-CAT) with corneal cross-linking (CXL) in eyes with keratoconus. METHODS: T-CAT with CXL was performed in 600 eyes (522 patients). Based on the T-CAT ablation plan, the theoretical maximum ablation depth was 50 µm after epithelium removal. After ablation, accelerated corneal cross-linking (CXL) was performed in the central 8-mm zone (9 mW/cm2 for 10 minutes in "epi-off" mode). The visual acuity and tomography were assessed. RESULTS: There was significant improvement in uncorrected (P = .001) and corrected (P = .001) distance visual acuity after the procedure. Keratometry, root mean square lower order aberrations and higher order aberrations, defocus, coma 90°, and spherical aberration reduced significantly after surgery at 10 years of follow-up (P < .005). All Pentacam (Oculus Optikgerate GmbH) tomographic variables showed significant changes indicating regularization after T-CAT (P < .005). Flattening of greater than 5.00 diopters in maximum keratometry was noted in 6 eyes (1%). Two of 600 eyes progressed postoperatively and required repeat CXL. CONCLUSIONS: T-CAT plus CXL is a safe and effective technique even in the long term for regularizing the anterior corneal surface with significant visual improvement and reduction in higher order corneal aberrations. [J Refract Surg. 2023;39(11):759-766.].

Coronavirus disease 19 (COVID-19) and viral keratouveitis - unraveling the mystery.

To demonstrate viral proteins/inflammatory cytokines in a patient with unilateral keratouveitis. Retrospective case report. A 70-year-old Asian-Indian male presented with acute onset of blurring of vision in the left eye (OS) of 2 days duration. He had was coronavirus disease 2019 (COVID-19)-positive 3 months earlier. He had undergone cataract surgery/retinal laser photocoagulation in both the eyes. The corrected distance visual acuity (CDVA) (Snellen) in the right eye (RE) (OD) and left eye (LE) (OS) was 20/20 and 20/80, respectively. OS showed decreased corneal sensation, Descemet's folds, mild stromal edema, and fine and pigmented keratic precipitates with anterior chamber 1+ flare and 1+ cells. Fundus evaluation showed scattered laser marks in the OD and temporal sectoral laser marks in OS. He was diagnosed with viral keratouveitis in OS. Tear samples were collected on Schirmer's strips and tear wash for mass spectrometry and cytokines, which had 368 and 451 viral proteins in the RE and LE, respectively, using nano liquid chromatography-mass spectrometry, which were more than controls. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and varicella zoster virus proteins were detected. Cytokine analysis using flow cytometer analysis showed higher inflammation in OS as compared to OD. The patient was treated with oral acyclovir and topical steroids and resulted in resolution of his keratouveitis. SARS-CoV-2 proteins were present in the tear sample 3 months after COVID-19. The presence of viral proteins does not indicate causality.

Artificial intelligence-based stratification of demographic, ocular surface high-risk factors in progression of keratoconus.

Purpose: The purpose of this study was to identify and analyze the clinical and ocular surface risk factors influencing the progression of keratoconus (KC) using an artificial intelligence (AI) model. Methods: This was a prospective analysis in which 450 KC patients were included. We used the random forest (RF) classifier model from our previous study (which evaluated longitudinal changes in tomographic parameters to predict "progression" and "no progression") to classify these patients. Clinical and ocular surface risk factors were determined through a questionnaire, which included presence of eye rubbing, duration of indoor activity, usage of lubricants and immunomodulator topical medications, duration of computer use, hormonal disturbances, use of hand sanitizers, immunoglobulin E (IgE), and vitamins D and B12 from blood investigations. An AI model was then built to assess whether these risk factors were linked to the future progression versus no progression of KC. The area under the curve (AUC) and other metrics were evaluated. Results: The tomographic AI model classified 322 eyes as progression and 128 eyes as no progression. Also, 76% of the cases that were classified as progression (from tomographic changes) were correctly predicted as progression and 67% of cases that were classified as no progression were predicted as no progression based on clinical risk factors at the first visit. IgE had the highest information gain, followed by presence of systemic allergies, vitamin D, and eye rubbing. The clinical risk factors AI model achieved an AUC of 0.812. Conclusion: This study demonstrated the importance of using AI for risk stratification and profiling of patients based on clinical risk factors, which could impact the progression in KC eyes and help manage them better.

Role of in vivo confocal microscopy in dry eye disease and eye pain.

Dry eye disease is known to have a lot of variability in presentation with overlapping subtypes. Understanding the pathology of this condition will guide therapeutic options. In vivo confocal microscopy is a diagnostic and imaging modality that provides high magnification and high-resolution images of all layers of the cornea and ocular surface. Various structures in the cornea and their alterations due to dry eye have been imaged. The impact of the tear film instability, inflammation, and altered homeostasis on the corneal epithelium, nerves, keratocytes, and dendritic cells have been evaluated across different studies. In addition, key features of IVCM in patients with neuropathic pain have been highlighted in this paper.

A randomized controlled study evaluating outcomes of intense pulsed light and low-level light therapy for treating meibomian gland dysfunction and evaporative dry eye.

Purpose: This randomized, controlled, blinded study evaluates the efficacy of intense pulsed light (IPL) therapy with low-level light therapy (LLLT) in the treatment of meibomian gland dysfunction (MGD) and evaporative dry eye (EDE) compared to a control group. Methods: Hundred patients with MGD and EDE were randomized into control (50 subjects, 100 eyes) and study group (50 subjects, 100 eyes). The study group underwent three sittings of IPL with LLLT 15 days apart and were followed up 1 month and 2 months after the last treatment sitting. The control group underwent sham treatment and was followed up at the same intervals. The patients were evaluated at baseline and 1 month and 3 months (post 1st treatment) for dry eye. Schirmer's test and tear breakup time (TBUT), OSDI, meibomian gland expression, and meibography. Results: The study group showed significant improvement in OSDI scores (P < 0.0001) compared to the control group and a significant improvement in TBUT (P < 0.005) compared to the control group. There was no change in schirmer's test and an improvement in the meibomian gland expression but not significant. Conclusion: The results show that a combined therapy of IPL with LLT is effective in treating MGD with EDE compared to controls, and repeated treatment sessions have a cumulative effect on the disease outcomes.

Effect of maqui-berry extract in dry eye disease - A clinical and molecular analysis.

Purpose: This study aims to investigate the effects of maqui-berry extract (MBE) in improving signs and symptoms of dry eye disease (DED) along with ocular surface inflammation in patients with DED. Methods: Twenty patients were randomly assigned to a MBE or a placebo group (PLC). DED parameters including Schirmer's test 1 (ST1), tear film break-up time (TBUT), ocular surface disease index (OSDI), and corneal staining were assessed before treatment and 2 months post-treatment. Tear fluid samples before and after treatment from a subset of these patients were collected from the study subjects using sterile Schirmer's strips, and the levels of interleukin (IL)-1ß, IL-10, IL-6, IL-17A, tumor necrosis factor-α (TNFα), matrix metalloproteinase-9 (MMP9), soluble intercellular adhesion molecule-1 (sICAM1), and vascular endothelial growth factor-A (VEGF-A) were measured using a microfluidic cartridge-based multiplex ELISA. Results: The MBE group demonstrated a significant (p < 0.05) decrease in OSDI scores along with a significant increase in Schirmer's test 1 compared to the PLC group. No significant change in TBUT and corneal staining was observed between the study groups. Levels of proinflammatory factors such as IL-1ß, IL-6, IL-17A, TNFα, and MMP9 were observed to be significantly reduced, along with a significant increase in IL-10 levels following treatment in the MBE group compared with the PLC group. Conclusion: Consumption of MBE resulted in the resolution of DED signs and symptoms, along with a reduction in ocular surface inflammation.

Role of artificial intelligence in determining factors impacting patients' refractive surgery decisions.

Purpose: To create a predictive model using artificial intelligence (AI) and assess if available data from patients' registration records can help in predicting definitive endpoints such as the probability of patients signing up for refractive surgery. Methods: This was a retrospective analysis. Electronic health records data of 423 patients presenting to the refractive surgery department were incorporated into models using multivariable logistic regression, decision trees classifier, and random forest (RF). Mean area under the receiver operating characteristic curve (ROC-AUC), sensitivity (Se), specificity (Sp), classification accuracy, precision, recall, and F1-score were calculated for each model to evaluate performance. Results: The RF classifier provided the best output among the various models, and the top variables identified in this study by the RF classifier excluding income were insurance, time spent in the clinic, age, occupation, residence, source of referral, and so on. About 93% of the cases that did undergo refractive surgery were correctly predicted as having undergone refractive surgery. The AI model achieved an ROC-AUC of 0.945 with an Se of 88% and Sp of 92.5%. Conclusion: This study demonstrated the importance of stratification and identifying various factors using an AI model which could impact patients' decisions while selecting a refractive surgery. Eye centers can build specialized prediction profiles across disease categories and may allow for the identification of prospective obstacles in the patient's decision-making process, as well as strategies for dealing with them.

Universal architecture of corneal segmental tomography biomarkers for artificial intelligence-driven diagnosis of early keratoconus.

AIMS: To develop a comprehensive three-dimensional analyses of segmental tomography (placido and optical coherence tomography) using artificial intelligence (AI). METHODS: Preoperative imaging data (MS-39, CSO, Italy) of refractive surgery patients with stable outcomes and diagnosed with asymmetric or bilateral keratoconus (KC) were used. The curvature, wavefront aberrations and thickness distributions were analysed with Zernike polynomials (ZP) and a random forest (RF) AI model. For training and cross-validation, there were groups of healthy (n=527), very asymmetric ectasia (VAE; n=144) and KC (n=454). The VAE eyes were the fellow eyes of KC patients but no further manual segregation of these eyes into subclinical or forme-fruste was performed. RESULTS: The AI achieved an excellent area under the curve (0.994), accuracy (95.6%), recall (98.5%) and precision (92.7%) for the healthy eyes. For the KC eyes, the same were 0.997, 99.1%, 98.7% and 99.1%, respectively. For the VAE eyes, the same were 0.976, 95.5%, 71.5% and 91.2%, respectively. Interestingly, the AI reclassified 36 (subclinical) of the VAE eyes as healthy though these eyes were distinct from healthy eyes. Most of the remaining VAE (n=104; forme fruste) eyes retained their classification, and were distinct from both KC and healthy eyes. Further, the posterior surface features were not among the highest ranked variables by the AI model. CONCLUSIONS: A universal architecture of combining segmental tomography with ZP and AI was developed. It achieved an excellent classification of healthy and KC eyes. The AI efficiently classified the VAE eyes as 'subclinical' and 'forme-fruste'.

A novel combination of corneal confocal microscopy, clinical features and artificial intelligence for evaluation of ocular surface pain.

OBJECTIVES: To analyse various corneal nerve parameters using confocal microscopy along with systemic and orthoptic parameters in patients presenting with ocular surface pain using a random forest artificial intelligence (AI) model. DESIGN: Observational, cross-sectional. METHODS: Two hundred forty eyes of 120 patients with primary symptom of ocular surface pain or discomfort and control group of 60 eyes of 31 patients with no symptoms of ocular pain were analysed. A detailed ocular examination included visual acuity, refraction, slit-lamp and fundus. All eyes underwent laser scanning confocal microscopy (Heidelberg Engineering, Germany) and their nerve parameters were evaluated. The presence or absence of orthoptic issues and connective tissue disorders were included in the AI. The eyes were grouped as those (Group 1) with symptom grade higher than signs, (Group 2) with similar grades of symptoms and signs, (Group3) without symptoms but with signs, (Group 4) without symptoms and signs. The area under curve (AUC), accuracy, recall, precision and F1-score were evaluated. RESULTS: Over all, the AI achieved an AUC of 0.736, accuracy of 86%, F1-score of 85.9%, precision of 85.6% and recall of 86.3%. The accuracy was the highest for Group 2 and least for Group 3 eyes. The top 6 parameters used for classification by the AI were microneuromas, immature and mature dendritic cells, presence of orthoptic issues and nerve fractal dimension parameter. CONCLUSIONS: This study demonstrated that various corneal nerve parameters, presence or absence of systemic and orthoptic issues coupled with AI can be a useful technique to understand and correlate the various clinical and imaging parameters of ocular surface pain.

Impact of tear optics on the repeatability of Pentacam AXL wave and iTrace in measuring anterior segment parameters and aberrations.

Purpose: To assess impact of tear optics on repeatability of a Scheimpflug device with a Hartmann Shack aberrometer and a ray tracing aberrometer. Methods: One hundred healthy and 100 postrefractive surgery eyes underwent dry eye evaluation including Schirmer's test and tear film break-up time (TBUT). They underwent optical quality analyzer (OQAS, Visio metrics S.L, Terrassa, Spain) to assess objective scatter index (OSI), three scans each on Pentacam AXL wave (OCULUS Optikgerate Gmbh, Wetzlar, Germany), iTrace (Tracey™ Technologies, Texas, USA) for flat, steep keratometry, thinnest corneal thickness, root mean square higher-order aberrations (RMS HOA), RMS lower-order aberrations (LOA), spherical aberrations, RMS COMA. Repeatability of Pentacam AXL wave and iTrace in healthy and postrefractive eyes (OSI >1 vs OSI <1) was studied using within-subject standard deviation (Sw) test-retest repeatability (TRT), coefficient of variation (COV). Results: OSI showed an inverse association with TBUT (P < 0.001). All measurements with Pentacam AXL wave with OSI < 1 had excellent repeatability, intraclass correlation coefficient (ICC) ranging from 0.88 for HOA, to 0.92 for LOA. The Sw, TRT, and COV of all aberration measurements were significantly lower (better) than those of iTrace. In eyes with OSI ≥1, the repeatability with Pentacam AXL wave dropped with ICC ranging from 0.77 for HOA, to 0.84 for LOA with lower Sw, TRT, and COV of all aberration measurements as compared to iTrace. Maximum variation was seen with HOA and minimum with LOA. Conclusion: Tear optics affected repeatability of Pentacam wave and iTrace. Pentacam wave had better repeatability in eyes with a poor tear film as compared to iTrace. Thus, the tear film can impact repeatability of an instrument and it is important to assess the tear film prior to imaging patients, which can change the way we interpret and image these patients.

Repeatability and Agreement of a New Scheimpflug Device and a Hartmann-Shack Aberrometer With a Ray-Tracing Aberrometer in Normal, Keratoconus, and CXL Groups.

PURPOSE: To assess repeatability and agreement of a Scheimpflug topographer and a Hartmann-Shack aberrometer with a ray-tracing aberrometer in normal, keratoconus, and corneal cross-linking (CXL) groups. METHODS: In this cross-sectional, observational study, normal, keratoconus, and CXL groups with 125 eyes in each of the three groups were included. All eyes underwent three sets of measurements, at a single visit, using the Pentacam AXL Wave (Oculus Optikgeräte GmbH) and iTrace (Tracey Technologies). Keratometry, pachymetry, objective refraction, and total ocular aberrations including root mean square (RMS) lower order aberrations (LOAs), RMS higher order aberrations (HOAs), RMS coma, and spherical aberrations (SA) were analyzed. Objective assessment of haze after CXL was done using the Pentacam AXL Wave. Repeatability was assessed using within-subject standard deviation (Sw), test-retest variability, within-subject coefficient of variation (COV), and intraclass correlation coefficient (ICC). Bland-Altman analysis assessed 95% limits of agreement and correlation coefficient (r) determined the strength of the relationship between measurements. RESULTS: The Pentacam AXL Wave had Sw for keratometry of 0.12 in the normal group and 0.15 in the keratoconus group and lower (poorer) Sw of 0.17 in the CXL group. For pachymetry, Sw was 9.18, 9.53, and 10.11 in the normal, keratoconus, and CXL groups, respectively. Total aberrations had ICCs ranging from 0.88 for RMS HOAs to 0.95 for SA in the normal group, 0.86 for RMS HOAs to 0.92 for SA in the keratoconus group, and 0.72 for RMS HOAs to 0.82 for SA (poorer) in the CXL group. In the normal group, mean differences between the two devices were nonsignificant for all parameters except SA (0.011 ± 0.038 µm, P < .01; limits of agreement = -0.09 to 0.07; r = 0.87). In the keratoconus group, mean differences were significant in all aberrations except RMS LOAs (-0.27 ± 0.85 µm, P = .10; limits of agreement = -3.3 to 3.8; r = 0.92). In the CXL group, all parameters varied significantly (P < .006). CONCLUSIONS: The Pentacam AXL Wave showed comparable repeatability in the normal and keratoconus groups, but was poorer in the CXL group, more so with increasing corneal haze. Both devices can be used interchangeably in normal eyes, except for SA, but not in eyes with keratoconus or CXL for aberration measurements. [J Refract Surg. 2022;38(3):201-208.].

Nodular scleritis-a rare presentation of COVID-19& variation with testing.

PURPOSE: - To report a rare case of patient presenting with nodular scleritis and SARS-CoV2. OBSERVATIONS: This case highlights a unique presentation of SARS-CoV2 positive patient with nodular scleritis as a presenting feature. Patient initially had ocular symptoms and developed only mild systemic features subsequently which did not require hospitalization. COVID testing done at different time points showed variable results which correlated with the ocular features. This patient was followed up during quarantine using tele-ophthalmology. CONCLUSION AND IMPORTANCE: This case highlights a possible rare presentation of a SARS-CoV2 patient with nodular scleritis and also importance of tele medicine during these unprecedented times.

Clinical and Molecular Outcomes After Combined Intense Pulsed Light Therapy With Low-Level Light Therapy in Recalcitrant Evaporative Dry Eye Disease With Meibomian Gland Dysfunction.

PURPOSE: Dry eye disease (DED) is a leading cause of ocular morbidity worldwide. This study evaluates the effects of combined light therapy [intense pulsed light (IPL) and low-level light therapy (LLLT)] on clinical and molecular outcomes in evaporative DED with meibomian gland dysfunction (MGD). METHODS: This prospective study evaluated 94 eyes (47 subjects) with chronic MGD treated with combined light therapy. Patients underwent a detailed evaluation of MGD and DED using the Ocular Surface Disease Index, dry eye tests-tear breakup time and Schirmer test, ocular surface staining, meibomian gland expressibility scoring, and meibography. Patients underwent a single session of combined light therapy (IPL + LLLT treatment) using the Eye-light device. All these tests were repeated at 3 and 6 months after treatment. Tear fluid and ocular surface wash samples were collected from a subset of patients before and after treatment for cellular and secreted immune factor profiling by flow cytometry. RESULTS: Combined light therapy (IPL + LLLT) demonstrated a marked improvement in the clinical metrics studied. Three months after treatment, Ocular Surface Disease Index showed a significant reduction in 95.6% ( P < 0.0001), tear breakup time increased in 72.3% ( P < 0.0001), and meibomian gland expressibility scoring increased in 80.8% ( P < 0.0001) of the eyes. These effects were observed to be sustained during the 6-month follow-up visit. Significant ( P < 0.05) reduction in tear fluid levels of interleukin-1ß, interleukin-17F, and MMP9; MMP9/TIMP1 ratio; and ocular surface B-cell proportions was observed. CONCLUSIONS: Combined light therapy shows promising results in patients with chronic MGD and DED, even in recalcitrant cases. Clinical and molecular factor alterations support the improved symptomatology and reduced inflammation.

Repeatability and agreement of wavefront aberrations of a new hybrid topographer and aberrometer in healthy eyes.

PURPOSE: To assess repeatability and agreement of the Pentacam AXL Wave with that of the iTrace aberrometer. SETTING: Narayana Nethralaya, Bangalore, India. DESIGN: Prospective, cross-sectional study. METHODS: All eyes of patients underwent 3 sets of measurements at a single visit, using Pentacam AXL Wave and iTrace. Lower-order aberrations (LOAs), higher-order aberrations (HOAs), and coma and spherical aberrations (SAs) were analyzed. Repeatability was assessed using within-subject (Sw) SD, test-retest variability (TRT), Sw coefficient of variation (CoV), and intraclass correlation coefficient (ICC). The Bland-Altman analysis was used to assess 95% limits of agreement (LoA) and the correlation coefficient (r) to determine strength of relationship between measurements. RESULTS: 100 eyes of 100 patients underwent measurements. Pentacam AXL Wave had repeatability with an ICC for total ocular aberrations ranging from 0.84 for HOAs to 0.92 for LOAs and for corneal from 0.76 for HOAs to 0.86 for LOAs. The Sw, TRT, and CoV of all aberrations were significantly lower (better) than those of iTrace (P < .001). The mean differences between 2 devices were insignificant for the comparison of all parameters, except for spherical aberration (0.011 [0.002571 to 0.02008]; P = .01). Both devices showed excellent correlations for ocular aberrations (total HOAs [P = .12, LoA = -0.52 to 0.025; r = 0.89]; LOAs [P = .14, LoA = -2.71 to 2.61; r = 0.96]; coma [P = .27, LoA = -0.11 to 0.12; r = 0.89]; and SA [P = .01, LoA = -0.09 to 0.07; r = 0.97]). CONCLUSIONS: The repeatability estimates for wavefront aberrations using Pentacam AXL Wave were significantly better than those using iTrace. Both devices showed excellent correlations for total ocular aberrations.

COVID-19 positivity rate in corneal tissue donors - A cause for concern!

Purpose: To determine the postmortem positivity for COVID-19 among voluntary eye donors who had been certified to have died of non-COVID-19 causes. Methods: All donors who donated their corneas (from March 2021 onward) were assessed for COVID-19 positivity tested by nasopharyngeal swab reverse transcription-polymerase chain reaction (RT-PCR) test. Relevant screening history was taken prior to collection. Strict precautions were taken during the retrieval as per the guidelines issued by the National Program for Control of Blindness and Visual Impairment and the Eye Bank Association of India, and the tissues were handled as per standard operating protocol. Results: 85 eye calls were attended during this period, of which 56 were home-based and 29 were from a hospital setting. Samples from 12 of the former group of donors were found to be positive for COVID-19 (14%). Conclusion: This study highlights the possibility of postmortem RT-PCR positivity in voluntary corneal tissue donors without a prior history of symptoms, signs, or diagnosis of illness suggestive of COVID-19. It is recommended that postmortem testing of donors should be done by RT-PCR for retrievals made during the pandemic.

Artificial Intelligence Efficiently Identifies Regional Differences in the Progression of Tomographic Parameters of Keratoconic Corneas.

PURPOSE: To develop an artificial intelligence (AI) model to effectively assess local versus global progression of keratoconus using multiple tomographic parameters. METHODS: This was a retrospective review of medical records of patients diagnosed as having keratoconus. A total of 1,884 Pentacam (Oculus Optikgeräte GmbH) scans of 366 eyes (296 patients) were analyzed. Based on an increase in maximum anterior curvature (Kmax), the eyes were classified as actual "progression" and "no progression." The corresponding changes in other Pentacam parameters were incorporated to train and cross-validate (five-fold) the AI models. Three AI models were trained (an increase in Kmax by A = 0.75 diopters [D], B = 1.00 D, and C = 1.25 D). The area under the curve (AUC), sensitivity, specificity, and classification accuracy, along with other metrics, were evaluated. RESULTS: The AUC, sensitivity, specificity, and classification accuracy were 0.90, 85%, 82%, and 83%, respectively, for Model A; 0.91, 86%, 82%, and 88%, respectively, for Model B; and 0.93, 89%, 81%, and 91%, respectively, for Model C. All models also predicted that 60% to 62% of the actual progression eyes had concomitant progression-associated changes in the other Pentacam parameters (global progression). However, there was discordance between increase in Kmax and concomitant associated changes in the other parameters in 38.8% to 40% of the eyes (local progression). CONCLUSIONS: The AI models identified the eyes where the increase in Kmax and corresponding progression-associated changes in the other parameters were in agreement. These eyes may require corneal cross-linking earlier than the rest. [J Refract Surg. 2021;37(4):240-248.].

Altered ocular surface immune cell profile in patients with dry eye disease.

PURPOSE: Aberrant inflammation and immune dysregulation are known pathogenic contributors in dry eye disease (DED). Aim of the study was to determine the proportions of immune cell subsets on the ocular surface (OS) of DED patients. METHODS: 15 healthy controls (22 eyes) and 48 DED subjects (36 eyes with evaporative DED - EDED; 60 eyes with aqueous deficient DED - ADED) were included in the study. Tear break up time (TBUT), Schirmer's test 1 (ST1), corneal staining (CS) and ocular surface disease index (OSDI) scoring were recorded. OS wash was used to collect immune cells on the OS of study subjects. The cells immunophenotyped using flow cytometry include leukocytes, neutrophils, macrophages, natural killer-NK cells and T cell subsets (CD4; CD8; double positive-DP; gamma delta-γδ and NK T cells). RESULTS: Significantly higher proportions of leukocytes, neutrophils, CD4 T cells, CD8 T cells, DP T cells and CD4/CD8 T cells ratio were observed in EDED and/or ADED patients. Significantly higher proportions of neutrophils and lower proportions of NK cells were observed in ADED subjects with corneal staining compared to those without and controls. Neutrophils/NK cells ratio was significantly higher in EDED and ADED subjects compared to controls. Correlation analysis revealed pathological relationships between proportions of leukocytes, neutrophils, CD4 T cells and Neutrophil/NK cells ratio with DED clinical parameters. CONCLUSION: OS immune cell subset proportion changes in DED patients were associated with DED types and severity. The data suggests the potential for a new generation of therapies targeting immune cells on the ocular surface.

Evaluating the safety and efficacy of compression sutures with intracameral perfluoropropane (C3F8) in the management of acute corneal hydrops.

BACKGROUND: To evaluate the safety and efficacy of using corneal compression sutures with intracameral perfluoropropane (C3F8) in patients presenting with acute corneal hydrops in ectatic disorders. METHODS: A retrospective analysis was done for 43 eyes of patients of acute corneal hydrops, managed using a combination of intracameral 14% C3F8 and full-thickness compression sutures. Time for resolution of edema, corneal thickness (CT) change on anterior segment ocular coherence tomography (ASOCT), and visual outcomes were assessed. RESULTS: Corneal edema resolved with a mean duration of 14.8 ± 3.5 days (range 10-21). The mean CT on ASOCT decreased from a mean of 1437 µm (689-2770 µm) preoperatively to 543 µm (434 -66 µm) on the complete resolution of corneal edema. CONCLUSION: Our results suggest that full-thickness compression sutures and intracameral C3F8 injection can restore the imperviousness of posterior stroma. This technique appears to be a safe and effective technique for faster resolution of corneal edema post hydrops.