The utility of software-detected non-invasive tear break-up in comparison to fluorescein tear break-up measurements.

Purpose: The purpose of this study is to characterize and discuss the difference between software-detected non-invasive tear break-up time (NIBUT) and the traditional clinical method of fluorescein break-up time (FBUT). Methods: Tear interferometry with the KOWA DR-1α (Kowa, Japan) and a standardized comprehensive ocular surface/tear evaluation were performed in 307 eyes. Software-detected NIBUT in the KOWA DR-1α images and the investigator-detected FBUT were compared. Results: Software-detected NIBUT was significantly shorter than investigator-measured FBUT. NIBUT was 3.1 ± 2.5 s (mean ± SD), whereas FBUT was 4.8 ± 3.0 s. This difference was due to three different patterns or conditions: a spot break immediately after eyelid opening, moderate to severe keratitis sicca, and epithelial basement membrane corneal dystrophy (EBMD). In these cases, rapid tear film disruption was not captured by FBUT. A spot break immediately after eye opening that rapidly disappears was observed with conjunctivochalasis. This type of break-up may be difficult to detect using fluorescein because the human eye cannot catch such rapid blinks or post-blink events. In the second group with severe corneal epithelial disease, break-up may occur over the entire corneal surface upon eye opening, and distinct fluorescein tear break-up may not be identified because of poor dye dilution or spread over the corneal surface, whereas the non-invasive break-up is not solution-dependent, and the software can detect a distinct appearance. In the third group with EBMD, it is possible that focal break-up in the fluorescein pattern over the epithelial elevations, which might be missed visually, can be detected by software in video images. Conclusion: We found that software-detected NIBUT is more sensitive in detecting tear break-up, can identify certain tear film disruptions that are missed by traditional FBUT, and may be more useful in distinguishing certain tear disorders.

Addressing corneal opacity after herpes zoster infection.

A 15-year-old boy was referred for corneal opacity evaluation. The patient had a previous herpes zoster virus (HZV) infection-varicella-zoster virus (VZV)-with ocular manifestation 1 year ago. After the infection, he developed a central corneal scar and decreased corrected distance visual acuity (CDVA) in the right eye. The slitlamp examination showed the right eye with central corneal opacity (involving anterior stroma), lacuna area between the haze, fluorescein negative, and no vascularization near the scar (Figure 1JOURNAL/jcrs/04.03/02158034-202406000-00019/figure1/v/2024-07-10T174224Z/r/image-tiff). The patient had been treated with oral valacyclovir and topical corticosteroids without any improvement of visual acuity or changes in opacity within the 1-year follow-up. His CDVA was 20/200 (-4.50 -0.75 × 25) in the right eye and counting fingers (-4.00) in the left eye. Intraocular pressure was 12 mm Hg in both eyes. Fundoscopy was normal in the right eye, but he had a macular scar in the left eye (diagnosed when he was 7 years). The left eye had no cornea signs. The patient has no comorbidity or previous surgeries. Considering this case, a corneal central scar in a 15-year-old boy, legally single eye only, and assuming it is an opacity in the anterior stroma, would you consider surgery for this patient? If so, which would you choose: Would you consider an excimer laser treatment of his ametropia while partially removing his opacity, a phototherapeutic keratectomy (PTK), or a PTK followed by a topography-guided treatment, femtosecond laser-assisted anterior lamellar keratoplasty (FALK), or deep anterior lamellar keratoplasty (DALK) or penetrating keratoplasty (depending on the scar depth)? Would you consider prophylactic acyclovir during and after surgery? Would you consider any other surgical step to prevent delayed corneal healing-persistent epithelial defect? Before the surgical approach, would you consider treating this patient with topical losartan (a transforming growth factor [TGF]-ß signaling inhibitor)? Would you first perform the surgery (which one) and then start the medication? Furthermore, if so, how long would you treat this patient? Would you consider treatment with another medication?

Ectoine Enhances Mucin Production Via Restoring IL-13/IFN-γ Balance in a Murine Dry Eye Model.

Purpose: This study aimed to explore protective effects and potential mechanism of ectoine, a natural osmoprotectant, on ocular surface mucin production in dry eye disease. Methods: A dry eye model was established in C57BL/6 mice exposed to desiccating stress (DS) with untreated (UT) mice as controls. DS mice were topically treated with 2.0% ectoine or PBS vehicle. Corneal epithelial defects were assessed by Oregon Green Dextran (OGD) fluorescent staining. Conjunctival goblet cells, ocular mucins, and T help (Th) cytokines were evaluated by immunofluorescent staining or ELISA, and RT-qPCR. Results: Compared with UT mice, corneal epithelial defects were detected as strong punctate OGD fluorescent staining in DS mice with vehicle, whereas ectoine treatment largely reduced OGD staining to near-normal levels. Conjunctival goblet cell density and cell size decreased markedly in DS mice, but was significantly recovered by ectoine treatment. The protein production and mRNA expression of two gel-forming secreted MUC5AC and MUC2, and 4 transmembrane mucins, MUC1, MUC4, MUC16, and MUC15, largely decreased in DS mice, but was restored by ectoine. Furthermore, Th2 cytokine IL-13 was inhibited, whereas Th1 cytokine IFN-γ was stimulated at protein and mRNA levels in conjunctiva and draining cervical lymph nodes (CLNs) of DS mice, leading to decreased IL-13/IFN-γ ratio. Interestingly, 2.0% ectoine reversed their alternations and restored IL-13/IFN-γ balance. Conclusions: Our findings demonstrate that topical ectoine significantly reduces corneal damage, and enhances goblet cell density and mucin production through restoring imbalanced IL-13/IFN-γ signaling in murine dry eye model. This suggests therapeutic potential of natural osmoprotectant ectoine for dry eye disease.

Single cell analysis of short-term dry eye induced changes in cornea immune cell populations.

Background: Dry eye causes corneal inflammation, epitheliopathy and sensorineural changes. This study evaluates the hypothesis that dry eye alters the percentages and transcriptional profiles of immune cell populations in the cornea. Methods: Desiccating stress (DS) induced dry eye was created by pharmacologic suppression of tear secretion and exposure to drafty low humidity environment. Expression profiling of corneal immune cells was performed by single-cell RNA sequencing (scRNA-seq). Cell differentiation trajectories and cell fate were modeled through RNA velocity analysis. Confocal microscopy was used to immunodetect corneal immune cells. Irritation response to topical neurostimulants was assessed. Results: Twelve corneal immune cell populations based on their transcriptional profiles were identified at baseline and consist of monocytes, resident (rMP) and MMP12/13 high macrophages, dendritic cells (cDC2), neutrophils, mast cells, pre T/B cells, and innate (γDT, ILC2, NK) and conventional T and B lymphocytes. T cells and resident macrophages (rMP) were the largest populations in the normal cornea comprising 18.6 and 18.2 percent, respectively. rMP increased to 55.2% of cells after 5 days of DS. Significant changes in expression of 1,365 genes (adj p < 0.0001) were noted in rMP with increases in cytokines and chemokines (Tnf, Cxcl1, Ccl12, Il1rn), inflammatory markers (Vcam, Adam17, Junb), the TAM receptor (Mertk), and decreases in complement and MHCII genes. A differentiation trajectory from monocytes to terminal state rMP was found. Phagocytosis, C-type lectin receptor signaling, NF-kappa B signaling and Toll-like receptor signaling were among the pathways with enhanced activity in these cells. The percentage of MRC1+ rMPs increased in the cornea and they were observed in the basal epithelium adjacent to epithelial nerve plexus. Concentration of the chemokine CXCL1 increased in the cornea and it heightened irritation/pain responses to topically applied hypertonic saline. Conclusion: These findings indicate that DS recruits monocytes that differentiate to macrophages with increased expression of inflammation associated genes. The proximity of these macrophages to cornea nerves and their expression of neurosensitizers suggests they contribute to the corneal sensorineural changes in dry eye.

Ectoine protects corneal epithelial survival and barrier from hyperosmotic stress by promoting anti-inflammatory cytokine IL-37.

PURPOSE: To explore novel role and molecular mechanism of a natural osmoprotectant ectoine in protecting corneal epithelial cell survival and barrier from hyperosmotic stress. METHODS: Primary human corneal epithelial cells (HCECs) were established from donor limbus. The confluent cultures in isosmolar medium were switched to hyperosmotic media (400-500 mOsM), with or without ectoine or rhIL-37 for different time periods. Cell viability and proliferation were evaluated by MTT or WST assay. The integrity of barrier proteins and the expression of cytokines and cathepsin S were evaluated by RT-qPCR, ELISA, and immunostaining with confocal microscopy. RESULTS: HCECs survived well in 450mOsM but partially damaged in 500mOsM medium. Ectoine well protected HCEC survival and proliferation at 500mOsM. The integrity of epithelial barrier was significantly disrupted in HCECs exposed to 450mOsM, as shown by 2D and 3D confocal immunofluorescent images of tight junction proteins ZO-1 and occludin. Ectoine at 5-20 mM well protected these barrier proteins under hyperosmotic stress. The expression of TNF-α, IL-1ß, IL-6 and IL-8 were dramatically stimulated by hyperosmolarity but significantly suppressed by Ectoine at 5-40 mM. Cathepsin S, which was stimulated by hyperosmolarity, directly disrupted epithelial barrier. Interestingly, anti-inflammatory cytokine IL-37 was suppressed by hyperosmolarity, but restored by ectoine at mRNA and protein levels. Furthermore, rhIL-37 suppressed cathepsin S and rescued cell survival and barrier in HCECs exposed to hyperosmolarity. CONCLUSION: Our findings demonstrate that ectoine protects HCEC survival and barrier from hyperosmotic stress by promoting IL-37. This provides new insight into pathogenesis and therapeutic potential for dry eye disease.

Ectoine, from a Natural Bacteria Protectant to a New Treatment of Dry Eye Disease.

Ectoine, a novel natural osmoprotectant, protects bacteria living in extreme environments. This study aimed to explore the therapeutic effect of ectoine for dry eye disease. An experimental dry eye model was created in C57BL/6 mice exposed to desiccating stress (DS) with untreated mice as controls (UT). DS mice were dosed topically with 0.5-2.0% of ectoine or a vehicle control. Corneal epithelial defects were detected via corneal smoothness and Oregon Green dextran (OGD) fluorescent staining. Pro-inflammatory cytokines and chemokines were evaluated using RT-qPCR and immunofluorescent staining. Compared with UT mice, corneal epithelial defects were observed as corneal smoothness irregularities and strong punctate OGD fluorescent staining in DS mice with vehicle. Ectoine treatment protected DS mice from corneal damage in a concentration-dependent manner, and ectoine at 1.0 and 2.0% significantly restored the corneal smoothness and reduced OGD staining to near normal levels. Expression of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) and chemokines CCL3 and CXCL11 was significantly elevated in the corneas and conjunctivas of DS mice, whereas 1.0 and 2.0% ectoine suppressed these inflammatory mediators to near normal levels. Our findings demonstrate that ectoine can significantly reduce the hallmark pathologies associated with dry eye and may be a promising candidate for treating human disease.

Immunologic basis for development of keratoconjunctivitis sicca in systemic autoimmune diseases: Role of innate immune sensors.

The literature is filled with citations reporting an increased incidence of chronic dry eye disease, also known as keratoconjunctivitis sicca, in patients with systemic autoimmune diseases such as rheumatoid arthritis, Sjögren's Syndrome, systemic sclerosis and lupus. As the most environmentally exposed mucosal surface of the body, the conjunctiva constantly responds to environmental challenges which are typically self limited, but when persistent and unresolved may provoke pathogenic innate and adaptive immune reactions. Our understanding of the pathophysiological mechanisms by which systemic autoimmune diseases cause dry eye inducing ocular surface inflammation continues to evolve. Conjunctival immune tone responds to self or foreign danger signals (including desiccating stress) on the ocular surface with an initial non-specific innate inflammatory response. If unchecked, this can lead to activation of dendritic cells that present antigen and prime T and B cells resulting in an adaptive immune reaction. These reactions generally resolve, but dysfunctional, hyper-responsive immune cells found in systemic autoimmune diseases that are recruited to the ocular surface can amplify inflammatory stress responses in the ocular surface and glandular tissues and result in autoimmune reactions that disrupt tear stability and lead to chronic dry eye disease. We here propose that unique features of the ocular surface immune system and the impact of systemic immune dysregulation in autoimmune diseases, can predispose to development of dry eye disease, and exacerbate severity of existing dry eye.

A Mouse Model for Corneal Neovascularization by Alkali Burn.

Corneal neovascularization (CoNV), a pathological form of angiogenesis, involves the growth of blood and lymph vessels into the avascular cornea from the limbus and adversely affects transparency and vision. Alkali burn is one of the most common forms of ocular trauma that leads to CoNV. In this protocol, CoNV is experimentally induced using sodium hydroxide solution in a controlled manner to ensure reproducibility. The alkali burn model is useful for understanding the pathology of CoNV and can be extended to study angiogenesis in general because of the avascularity, transparency, and accessibility of the cornea. In this work, CoNV was analyzed by direct examination under a dissecting microscope and by immunostaining flat-mount corneas using anti-CD31 mAb. Lymphangiogenesis was detected on flat-mount corneas by immunostaining using anti-LYVE-1 mAb. Corneal edema was visualized and quantified using optical coherence tomography (OCT). In summary, this model will help to advance existing neovascularization assays and discover new treatment strategies for pathologic ocular and extraocular angiogenesis.

Differentially Expressed Tear Proteins in Sjögren's Syndrome Keratoconjunctivitis Sicca.

Purpose: The purpose of this study was to determine if there are significant differences in the concentrations of tear proteins in Sjögren's syndrome keratoconjunctivitis sicca (SS KCS) compared to healthy controls. Methods: Tear samples were collected with unmarked Schirmer strips from 15 patients with SS KCS and 21 healthy controls. Tear protein was eluted and the concentration measured. Inflammatory mediators were assayed with a Raybiotech L-507 glass slide array and normalized by strip wetting length. All patients underwent an ocular surface exam to evaluate tear break-up time (TBUT), corneal fluorescein (CF) staining, and conjunctival (CJ) staining. The symptom assessment questionnaire in dry eye (SANDE) scores were collected for all patients. Results: Two hundred fifty-three of the 507 tear proteins analyzed were significantly different in patients with SS compared to controls. Two hundred forty-one if the proteins were upregulated and 12 were downregulated. One hundred eighty-one differentially expressed proteins were significantly correlated with all four clinical parameters: TBUT, CF staining, CJ staining, and SANDE score. Conclusions: These findings indicate that hundreds of factors can be assayed in tear proteins collected from a Schirmer strip. The results suggest tear protein concentrations are altered in patients with SS KCS compared to controls. The upregulated tear proteins correlated with clinical measures of dry eye symptoms and disease severity. Translational Relevance: Tear proteins could serve as important biomarkers for studying pathogenesis and in clinical diagnosis and management of SS KCS.

Dry eye disease and blinking behaviors: A narrative review of methodologies for measuring blink dynamics and inducing blink response.

Dry eye disease (DED) is a leading cause of ophthalmology clinical encounters with prevalence ranging from 8.7% to 64% in various populations. Blinking is an endogenous process to refresh the tear film, clear debris and maintain quality vision. Altered blinking behavior is a common feature of DED and is implicated in the pathology of the disease. However, lack of a comprehensive review on the relationship between altered blinking behavior and DED is notable in the literature. Blinking behavior may be an effect of DED due to an unstable tear film sensitizing a motor response or be its cause due to destabilization of the tear film in conditions such as benign essential blepharospasm. In this comprehensive review, we summarize the current models and theories of tear film dynamics and blinking behavior to better understand their connection to DED and introduce contemporary technologies and measurement tools used in the evaluation and induction of blinking behavior. We also describe future directions of research to better understand the relationship between DED and blinking and explore therapies that address the abnormal blinking component of DED.

Induction of Innate Inflammatory Pathways in the Corneal Epithelium in the Desiccating Stress Dry Eye Model.

Purpose: To determine whether 24-hour exposure to the desiccating stress (DS) dry eye model induces NF-kB and NLRP3 inflammasome pathways in the mouse cornea epithelium. Methods: Six- to 8-week-old C57BL/6J mice were housed under normal humidity (nonstressed) or subjected to DS from a drafty, low-humidity environment combined with subcutaneous scopolamine four times/day for one day to suppress tear production (DS1). Cornea whole mounts were prepared for immunofluorescent staining, or the corneal epithelium was scraped for NF-kB p-p65 ELISA, Western blot, or real-time PCR to detect NF-kB and inflammasome pathway proteins and gene transcripts, respectively. Results: NF-kB phospho-p65 protein, nuclear NF-kB p-p65, and expression of the NF-kB inducible cytokines (IL-12a, IL-12b, and lymphotoxin b [Ltb]) and chemokine (CCL-2) genes were significantly increased in DS1 compared to nonstressed control. NLRP3 protein and RNA transcripts significantly increased in DS1. NLRP3 and Caspase-1 immunostaining increased in the cornea epithelium at DS1. At DS1 there was no change in IL-18 and a decrease in IL-1ß mRNA transcripts; however, levels of bound and total IL-18 protein increased at DS1, and the level of mature IL-1ß increased from DS1 to DS5. Conclusions: These findings indicate innate NF-kB and NLRP3 inflammasome inflammatory pathways are induced in the corneal epithelium within one day in the DS dry eye model. NF-kB activation was associated with increased expression of inflammatory mediators involved in dry eye. Induction of these pathways is accompanied by increased bound/total IL-18 and mature IL-1ß.

Comparison of Efficacy and Inflammatory Response to Thermoconjunctivoplasty Performed with Cautery or Pulsed 1460 nm Laser.

Conjunctivochalasis is a degenerative condition of the conjunctiva that disrupts tear distribution and causes irritation. Thermoreduction of the redundant conjunctiva is required if symptoms are not relieved with medical therapy. Near-infrared laser treatment is a more controlled method to shrink the conjunctiva than thermocautery. This study compared tissue shrinkage, histology, and postoperative inflammation in thermoconjunctivoplasty performed on the mouse conjunctiva using either thermocautery or pulsed 1460 nm near-infrared laser irradiation. Three sets of experiments were performed on female C57BL/6J mice (n = 72, 26 per treatment group and 20 control) to assess conjunctival shrinkage, wound histology, and inflammation 3 and 10 days after treatment. Both treatments effectively shrunk the conjunctiva, but thermocautery caused greater epithelial damage. Thermocautery caused greater infiltration of neutrophils on day 3 and neutrophils and CD11b+ myeloid cells on day 10. The thermocautery group had significantly higher conjunctival expression of IL-1ß on day 3. Expression of chemokine CCL2 was higher in the conjunctiva on day 3 and tear concentrations were higher on day 7 in the laser group. These results suggest that pulsed laser treatment causes less tissue damage and postoperative inflammation than thermocautery while effectively addressing conjunctivochalasis.

Clinical diagnosis and management of Demodex blepharitis: the Demodex Expert Panel on Treatment and Eyelid Health (DEPTH).

BACKGROUND: Twelve ocular surface disease experts convened to achieve consensus about Demodex blepharitis (DB) using a modified Delphi panel process. METHODS: Online surveys were administered using scaled, open-ended, true/false, and multiple-choice questions. Consensus for questions using a 1 to 9 Likert scale was predefined as median scores of 7-9 and 1-3. For other question types, consensus was achieved when 8 of 12 panellists agreed. Questions were randomized, and results of each survey informed the following survey. RESULTS: Twelve practitioners comprised the Demodex Expert Panel on Treatment and Eyelid Health (DEPTH). Following 3 surveys, experts agreed that DB is chronic (n = 11) and recurrent (n = 12) and is often misdiagnosed. Consensus was achieved regarding inflammation driving symptoms (median = 7; range 7-9), collarettes as the most common sign (n = 10) and pathognomonic for DB (median = 9; range 8-9), and itching as the most common symptom (n = 12). Panellists agreed that DB may be diagnosed based on collarettes, mites, and/or patient symptoms (n = 10) and felt that patients unresponsive to typical therapies should be evaluated for DB (n = 12). Consensus about the most effective currently available OTC treatment was not reached. CONCLUSIONS: The Delphi methodology proved effective in establishing consensus about DB, including signs, symptoms, and diagnosis. Consensus was not reached about the best treatment or how to grade severity. With increased awareness, eyecare practitioners can offer DB patients better clinical outcomes. A follow-up Delphi panel is planned to obtain further consensus surrounding DB treatment.

Non-invasive and objective tear film breakup detection on interference color images using convolutional neural networks.

PURPOSE: Dry eye disease affects hundreds of millions of people worldwide and is one of the most common causes for visits to eye care practitioners. The fluorescein tear breakup time test is currently widely used to diagnose dry eye disease, but it is an invasive and subjective method, thus resulting in variability in diagnostic results. This study aimed to develop an objective method to detect tear breakup using the convolutional neural networks on the tear film images taken by the non-invasive device KOWA DR-1α. METHODS: The image classification models for detecting characteristics of tear film images were constructed using transfer learning of the pre-trained ResNet50 model. The models were trained using a total of 9,089 image patches extracted from video data of 350 eyes of 178 subjects taken by the KOWA DR-1α. The trained models were evaluated based on the classification results for each class and overall accuracy of the test data in the six-fold cross validation. The performance of the tear breakup detection method using the models was evaluated by calculating the area under curve (AUC) of receiver operating characteristic, sensitivity, and specificity using the detection results of 13,471 frame images with breakup presence/absence labels. RESULTS: The performance of the trained models was 92.3%, 83.4%, and 95.2% for accuracy, sensitivity, and specificity, respectively in classifying the test data into the tear breakup or non-breakup group. Our method using the trained models achieved an AUC of 0.898, a sensitivity of 84.3%, and a specificity of 83.3% in detecting tear breakup for a frame image. CONCLUSIONS: We were able to develop a method to detect tear breakup on images taken by the KOWA DR-1α. This method could be applied to the clinical use of non-invasive and objective tear breakup time test.

Delphi Panel Consensus Regarding Current Clinical Practice Management Options for Demodex blepharitis.

Purpose: To obtain consensus on Demodex blepharitis (DB) treatment using a modified Delphi panel process. Methods: Literature search identified gaps in knowledge surrounding treatment of DB. Twelve ocular surface disease experts comprised the Demodex Expert Panel on Treatment and Eyelid Health (DEPTH). They completed a live roundtable discussion in addition to 3 surveys consisting of scaled, open-ended, true/false, and multiple-choice questions pertaining to the treatment of DB. Consensus for scaled questions using a 1 to 9 Likert scale was predefined as median scores of 7-9 and 1-3. For other question types, consensus was achieved when 8 of 12 panelists agreed. Results: The experts agreed that an effective therapeutic agent for treatment of DB would likely decrease the necessity of mechanical intervention, such as lid scrubs or blepharoexfoliation (Median = 8.5; Range 2-9). When treating DB, panelists believed that collarettes serve as a surrogate for mites, and that eliminating or reducing collarettes should be the main clinical goal of treatment (Median = 8; Range 7-9). The panelists would treat patients with at least 10 collarettes, regardless of other signs or symptoms and agreed that DB can be cured, but there is always the possibility for a reinfestation (n = 12). There was also consensus that collarettes, and therefore mites, are the primary treatment target and the way by which clinicians can monitor patient response to therapy (Median = 8; Range 7-9). Conclusion: Expert panelists achieved consensus on key facets of DB treatment. Specifically, there was consensus that collarettes are pathognomonic for DB, that DB patients with >10 collarettes should be treated even in the absence of symptoms, and that treatment efficacy can be tracked by collarette resolution. By increasing awareness about DB, understanding the goals of and monitoring treatment efficacy, patients will receive better care and, ultimately, better clinical outcomes.

Anti-Inflammatories in the Treatment of Dry Eye Disease: A Review.

Inflammation is an important driver of dry eye disease (DED) pathogenesis. An initial insult that results in the loss of tear film homeostasis can initiate a nonspecific innate immune response that leads to a chronic and self-sustaining inflammation of the ocular surface, which results in classic symptoms of dry eye. This initial response is followed by a more prolonged adaptive immune response, which can perpetuate and aggravate inflammation and result in a vicious cycle of chronic inflammatory DED. Effective anti-inflammatory therapies can help patients exit this cycle, and effective diagnosis of inflammatory DED and selection of the most appropriate treatment are therefore key to successful DED management and treatment. This review explores the cellular and molecular mechanisms of the immune and inflammatory components of DED, and examines the evidence base for the use of currently available topical treatment options. These agents include topical steroid therapy, calcineurin inhibitors, T cell integrin antagonists, antibiotics, autologous serum/plasma therapy, and omega-3 fatty acid dietary supplements.

Quantitative assessment of botulinum toxin injection on blink rate in blepharospasm.

PURPOSE: To objectively measure the blink rate in patients with blepharospasm managed by botulinum toxin type-A injections. METHODS: In this prospective, non-interventional case series, the complete blink rates of subjects were measured before incobotulinumtoxina injection and at follow-up within 4 weeks using slow-motion video-taping. Additionally, subjects graded the frequency of blinking, the severity of light-sensitivity, and the severity and frequency of dry eye symptoms on a categorical visual analog scale. The results are reported as median (range). RESULTS: Ten subjects were enrolled, with nine females. The total duration of treatment was 70 (5-116) months with total of 27.5 (2-51) injections. The subjects were grouped as short-time (<52w) or long-time (>52w) treatments. The median age, follow-up time, and injected doses were 73.5 (49-81) years, 21 (14-28) days, and 38 (8-47) units, respectively, with no significant difference between groups. The total complete blinks per minute before incobotulinumtoxina injection was 39 (23-64) which decreased to 18.5 (1-60) at follow-up (p = 0.004). The average change in complete blink rate was -67.4 ± 23.7% in long-time and -45.2 ± 31.2% in short-time groups (mean ± SD, p = 0.01). The total self-graded frequency of blinking and light-sensitivity decreased significantly at follow-up (p = 0.004, p = 0.047, respectively). Similar patterns of subject reported grades were seen in both groups. CONCLUSION: Videotaping is a low-cost method for objective measurement of blink rate in blepharospasm patients after incobotulinumtoxina injection. There was a significant reduction in blink rate after incobotulinumtoxina injections with higher percentage of change in the long-time treatment group. Incobotulinumtoxina injection also significantly improves subjective photophobia.

Non-Invasive Tear Break-Up Detection with the Kowa DR-1α and Its Relationship to Dry Eye Clinical Severity.

The purpose of this study is to compare visual versus software detection of non-invasive tear break-up with the KOWA DR-1α tear interferometer and investigate the relationship between non-invasive tear break-up time (NIBUT) and dry eye clinical severity. Tear interferometry with the KOWA DR-1α, together with a standardized comprehensive ocular surface/tear evaluation, was performed on 348 consecutive eyes. Investigator visually detected or software detected non-invasive tear break-up and NIBUT were measured and compared on a subset of these examinations. The relationship between software-detected NIBUT and categorical dry eye severity based on irritation symptoms and corneal and conjunctival dye staining scores was determined. The sensitivity of visual (frame-by-frame) or software detected non-invasive tear break-up in eyes with tear instability (FBUT < 10) was similar (range 63−69%). NIBUT, measured visually or by software, had a correlation coefficient of 0.87. NIBUT was significantly lower in severity levels 2 and 3 compared to levels 0 + 1, and level 3 was significantly lower than level 2. In conclusion, there is a good correlation between investigator visually detected and software-detected tear break-up and tear break-up time in the KOWA DR-1α interferometric fringe images. Software-detected NIBUT is a clinically relevant measure of dry eye clinical severity.

Imbalanced IL-37/TNF-α/CTSS signaling disrupts corneal epithelial barrier in a dry eye model in vitro.

PURPOSE: To explore novel role and molecular mechanism of a natural anti-inflammatory cytokine interleukin (IL) 37 in preventing corneal epithelial barrier disruption from hyperosmolar stress as can occur in dry eye disease. METHODS: Primary human corneal epithelial cells (HCECs) were cultured from fresh donor limbal explants. An in vitro dry eye model with hyperosmolar stress was established by switching HCECs from isosmolar (312mOsM) to hyperosmolar medium (350-500 mOsM), and some cells were treated with rhIL-37 or rhTNF-α, for different periods (2-48 h). The expression of cytokines and cathepsin S, and barrier protein integrity were evaluated by RT-qPCR, ELISA, and immunofluorescent staining with confocal microscopy. RESULTS: The integrity of epithelial barrier was significantly disrupted in HCECs exposed to hyperosmolar medium, as shown by immunofluorescent images of tight junction (TJ, ZO-1, occludin and claudin-1) and adheren junction (E-cadherin) proteins. TNF-α accentuated hyperosmolar-induced disruption of TJ barrier functional integrity whereas exposure to IL-37 blunted or even reversed these changes. Cathepsin S, encoded by CTSS gene, was found to directly disrupt epithelial barrier integrity. Interestingly, CTSS expression was significantly induced by TNF-α and hyperosmolarity, while exogenous rhIL-37 inhibited TNF-α and CTSS expression at mRNA and protein levels following hyperosmolar stress. Furthermore, rhIL-37 restored barrier protein integrity, observed in 2D and 3D confocal immunofluorescent images, in HCECs under hyperosmolar stress. CONCLUSION: Our findings demonstrate a novel signaling pathway by which anti-inflammatory cytokine IL-37 prevents corneal epithelial barrier disruption under hyperosmotic stress via suppressing TNF-α and CTSS expression. This study provides new insight into mechanisms protecting corneal barrier in dry eye disease.

Initial experiences using plasma rich in growth factors to treat keratoneuralgia.

Keratoneuralgia, a clinical diagnosis of sensitized corneal pain without visible ocular surface damage, generally has minimal response to conventional therapies. Causes include refractive surgery and chronic dry eye. We evaluated the efficacy of Plasma Rich in Growth Factors (PRGF), a novel treatment prepared using a commercially available kit, in patients with keratoneuralgia. A retrospective chart review identified patients who had the clinical diagnosis of keratoneuralgia and were treated with PRGF for at least 3 months from October 2015 to April 2020 at a single academic institution. Both objective eye exam findings and concurrent treatments were obtained at baseline, 3 months, and final visit (if available). A questionnaire was administered to identified patients, including symptoms scores measured with a visual analog scale. The results of this survey and other objective findings were compared before and after PRGF treatment. 16 out of 32 patients (50%) with a mean follow-up period of 33 ± 26 months answered the questionnaire. Refractive surgeries were the cause of keratoneuralgia in 14 patients (87.5%), with LASIK the most common procedure (11 patients, 69%). There were no adverse events recorded or reported. Symptom scored by VAS in a modified Symptoms Assessment in Dry Eye questionnaire significantly decreased after PRGF use (85 ± 16 to 45 ± 33, p = 0.0002). Ten patients (63%) reported PRGF is superior to other therapy and would recommend to others. There were no significant trends in visual acuity, objective exam findings, or concurrent treatments after PRGF treatment. PRGF is safe and can potentially alleviate symptoms in patients with keratoneuralgia, a rare but devastating complication after refractive surgery. Prospective trial is indicated to explore PRGF as a potentially useful treatment for keratoneuralgia.