Ocular Surface Research Articles

Intense pulsed light therapy for ocular surface diseases.

Intense pulsed light (IPL) is a non-laser, high-intensity light source that has been shown to play a valuable role in dermatology and has been adopted in ophthalmology for treating meibomian gland dysfunction (MGD). In this review, we discuss the mechanism of action of IPL, including its benefits in ophthalmology. IPL therapy has been shown to improve tear film stability, meibomian gland (MG) function, and subjective symptoms of ocular dryness in MGD patients. Moreover, emerging evidence suggests that IPL therapy is beneficial for other ocular surface diseases, such as blepharitis and chalazia. Hence, it can be inferred that IPL has potential as a therapeutic modality in future applications. Large clinical and experimental trials are needed to exploit the full potential of IPL as a treatment for recurrent chalazia, Sjögren's syndrome, and other causes of dry eye disease (DED). This paper reviews the published literature related to the application of IPL for treating ocular surface diseases.

Prognostic indicators of corneal ulcer clinical outcomes at a tertiary care center in the Bronx, New York

PurposeCorneal ulcers frequently result in ocular morbidity and may lead to permanent visual impairment if severe or untreated. This study aims to evaluate the association of patient factors and ocular exam findings on clinical outcomes for patients diagnosed with a corneal ulcer at a tertiary care center in the Bronx, New York.MethodsA retrospective chart review was conducted on all ambulatory and admitted patients diagnosed with a corneal ulcer (identified using ICD-10 code H16.0) at Montefiore Medical Center, Bronx, NY between 2016–2022. Patient demographics, presence of known risk factors, characteristics of subsequent clinical course, and microbiological studies were noted. Clinical outcomes following treatment were longitudinally evaluated and categorized based upon the following criteria: 1) ‘No Surgical Intervention’: No severe complications or surgery required after presentation, 2) ‘Surgical Intervention’: Decline in BCVA with surgery required for a severe complication.ResultsThe search criteria identified 205 patients (205 eyes) with the diagnosis of a corneal ulcer. Mean age was 55.3 ± 21.1 years (mean ± SD). Mean ulcer area at presentation was 7 ± 10.5 mm2. Mean LogMAR at presentation was 1.2 ± 1, and following treatment, improved to 1.0 ± 1. ‘Surgical Intervention’ outcome was associated with advanced age (p = 0.005), presence of ocular surface disease (p = 0.008), central location of ulcer (p = 0.014), greater ulcer area at presentation (p = 0.003), worse visual acuity at presentation (p < 0.001), and isolation of fungi (p = 0.004).ConclusionIdentification of risk factors associated with a poor clinical prognosis can guide treatment and inform expectations for patients diagnosed with a corneal ulcer. Our study highlights the importance of timely diagnosis, work-up, and initiation of appropriate management, particularly in vulnerable populations where access to specialty care is logistically challenging.

Prevalence and Risk Factors of Dry Eye Disease in the South of Palestine.

The prevalence of dry eye disease (DED) is rising globally and needs to be urgently addressed by medical professionals because it lowers patients' quality of life. There are as yet no available data in the literature about the prevalence of and risk factors for DED in the Gaza Strip, a gap that the present study seeks to address. A cross-sectional study was carried out between March and August 2022 in Gaza governorates using a proportional stratified sampling technique. Only Gazan individuals ≥ 18 years old and able to follow the instructions were included. The Ocular Surface Disease Index (OSDI) questionnaire, which has previously been translated into Arabic and validated, was applied to evaluate DED symptoms. Subjective clinical tests for DED conducted were tear meniscus height (TMH), meibomian gland dysfunctions (MGDs), Marx line (ML), conjunctival Lissamine green staining (LGS), tear film break-up time test (TBUT), corneal fluorescein staining (CFS) and Schirmer II tear test (STT). DED was defined based on an Arab-OSDI score ≥ 13 and at least one positive clinical sign. A total of 426 participants were assessed from four areas (North Gaza Strip, 82; Gaza City, 147; Mid-Zone Gaza Strip, 62; South Gaza Strip, 135). The prevalence of DED in the present study was 31.5% (95% CI: 27.1, 36.1). Age > 50 years old (odds ratio [OR] = 10.45; 95% CI: 2.95, 37.05; P < 0.001), female gender (OR = 3.24; 95% CI: 1.40, 7.52, P = 0.006), menopause or pregnancy (OR = 2.59; 95% CI: 1.25, 5.35; P = 0.03) and pharmacotherapy (artificial tears; OR = 9.91; 95% CI: 2.77, 35.46; P < 0.001) were each associated with DED symptoms. South Gaza Strip (OR = 0.04; 95% CI: 0.01, 0.12; P < 0.001), unemployed (OR = 11.67; 95% CI: 1.43, 95.44; P = 0.02), non-consumption of caffeine (OR = 0.40; 95% CI: 0.19, 0.88; P = 0.02) and TMH < 0.2 (OR = 1.80; 95% CI: 1.02, 3.19; P = 0.04) were associated with TBUT < 5 s. LGS was associated with those > 50 years old (OR = 2.70; 95% CI: 1.38, 5.28; P = 0.004), previous refractive or ocular surface surgeries (OR = 2.97; 95% CI: 1.34, 6.59; P = 0.008) and CFS ≥ 1 (OR = 1.91; 95% CI: 1.07, 3.44; P = 0.03). Various aspects of DED were linked with different risk factors, suggesting that DED subtypes have different underlying pathophysiologies.

Phospholipid analyses of rabbit ocular surface tissues

The tissues of the integument covering the ocular surface comprise a mucus membrane functioning as a protective physical barrier and has the ability to mount a defensive inflammatory response. Since lipid metabolism has a role in both of these functions, we studied normal membrane phospholipids (PL) of the cornea and bulbar conjunctiva to (1) determine baseline PL profiles of these tissues, (2) compare and contrast these individual PL metabolite profiles as well as groups of metabolites, and (3) describe pathway-specific metabolic interrelations among these tissues. Corneal and conjunctival tissue samples were isolated from rabbit eyes (n = 30) and extracted with chloroform-methanol using a modified Folch procedure. 31P nuclear magnetic resonance spectroscopy was used to qualitatively and quantitatively measure tissue PL profiles. The cornea and conjunctiva, respectively, have the following PL composition (mole % of total detected phospholipid): phosphatidylglycerol (PG) –, 0.4; lysophosphatidylethanolamine 1.2, –; phosphatidic acid –, 0.4; diPG (cardiolipin) 2.1, 3.5; unknown PL at the chemical shift of 0.13 δ 1.5, 0.9; ethanolamine plasmalogen 11.2, 13.0; phosphatidylethanolamine 11.5, 12.8; phosphatidylserine 8.9, 10.1; sphingomyelin 10.2, 10.7; lysophosphatidylcholine 0.9, 1.4; phosphatidylinositol 5.3, 5.3; phosphatidylcholine (PC) plasmalogen or alkylacylPC 2.2, 1.9; PC 45.1, 40.0. In addition, 28 PL metabolic indices were calculated from these data, which permitted pathway-specific lipid analyses. This study (1) establishes PL profiles of the two ocular tissues of the integument that cover the surface of the eye, (2) compares and contrasts indices comprised of ratios and combinations of PL, and (3) describes pathway-specific metabolic interrelations among these tissues to serve as baselines for studies involving the distribution of tissue phospholipids.

An important contributing factor in dry eye disease: somatization.

Somatization is an important mental process that may causes medically unexplained and treatment-resistant somatic symptoms. The aim of the study is assess the presence of somatization in patients with dry eye disease (DED). Eighty-eight patients with no objective DED finding and ongoing DED treatment were included in this prospective and observational study. Patients with subjective symptoms formed the symptom group and patients without subjective symptoms formed the control group. All patients were scored with the Turkish version of the Ocular Surface Disease Index (OSDI), Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A), Symptom Checklist-90-R (SCL-90R) somatization subscale, Toronto Alexithymia Scale (TAS), Pain Catastrophizing Scale (PCS), and Symptom Interpretation Questionnaire (SIQ). Mean OSDI score was significantly higher in the symptom group than in the control group. The mean HAM-D and HAM-A outcomes did not differ between the groups. The mean SCL-90R somatization subscale, TAS, and PCS scores were significantly higher in the symptom group than in the control group. In the SIQ, somatic attributional style score was significantly higher in the symptom group than in the control group. The SCL-90R somatization subscale, PCS, and somatic attributional style scores had positive and mild-moderate correlation with OSDI scores in the symptom group. The TAS score had positive and moderate correlation with OSDI scores in all sample analyses. Somatization should be considered in patients with DED with chronic ocular surface symptoms. Presence of subjective symptoms resistant to treatment may be an indicator of somatization.

Conditional reprogrammed human limbal epithelial cell model for anti-SARS-CoV-2 drug screening

To minimize the global pandemic COVID-19 spread, understanding the possible transmission routes of SARS-CoV-2 and discovery of novel antiviral drugs are necessary. We describe here that the virus can infect ocular surface limbal epithelial, but not other regions. Limbal supports wild type and mutant SARS-CoV-2 entry and replication depending on ACE2, TMPRSS2 and possibly other receptors, resulting in slight CPE and arising IL-6 secretion, which symbolizes conjunctivitis in clinical symptoms. With this limbal model, we have screened two natural product libraries and discovered several unreported drugs. Our data reveal important commonalities between COVID-19 and ocular infection with SARS-CoV-2, and establish an ideal cell model for drug screening and mechanism research.

Design and validation of a piezoelectric diaphragm micropump for drug delivery

There is a common eye ailment called Dry Eye Disease (DED) that causes symptoms of discomfort, visual disturbance, and tear film instability, which cause damage to the ocular surface. For treatment of this illness, the application of artificial tear fluid is usually prescribed. This work presents the design process of a piezoelectric micropump to become part of an automatic pumping system for delivering artificial tear fluid to people suffering from DED. Low polarizing voltage, portability, and achieving a variable output flow rate in the range of 1 µl/min, which is the necessary range needed by a person suffering from DED, are the focus of this design. Standard microfabrication techniques widely used in the CMOS industry and for MEMS development will be used for manufacturing the proposed micropump. For this reason, the materials and manufacturing processes involved must be CMOS-compliant. For the piezoelectric actuator, zinc oxide (ZnO) was selected due to its compatibility with CMOS technology and because it is readily available in thin film form through a sputtering process. Other materials involved in the device are silicon and aluminum. The design was validated through finite element analysis software, COMSOL Multiphysics®. The maximum flow rate obtained by a single micropump device was 2.51µl/min operating at 20V peak with a frequency of 900Hz. Also, the flow rate is controllable through variations in frequency, thus making it suitable for the application previously described.

Outcome of intense-pulsed light therapy versus combination of intense-pulsed light and low-level light therapy for the treatment of meibomian gland dysfunction

Objectives: The objective of this study was to study the efficacy of intense pulsed light (IPL) therapy and a combination of intense pulse light therapy and low-level light therapy (LLLT) in treating meibomian gland dysfunction (MGD). Material and Methods: In this prospective and hospital-based interventional study, 32 patients were enrolled between April 2023 and January 2024 in the Department of Cornea, Sri Sankaradeva Nethralaya, Guwahati. The clinical evaluation was done included the ocular surface disease index (OSDI-6) questionnaire score, tear film break-up time (TBUT), Schirmer test I, slit-lamp examination for lid evaluation to see signs of pitting, telangiectasia, meibomian gland expressibility, meibography (to see gland dropout assessment), and meibomian gland loss percentage (MGL%). The enrolled participants were randomly allocated to receive IPL and combination light therapy (IPL+LLLT) in a 1:1 ratio. Results: Sixty-two eyes of 31 patients were included in this study. In the IPL group, the level of dryness (LOD) improved in nine (56.25%) cases and remained the same in seven cases (73.75%). In the IPL+ LLLT group, the LOD improved in eight cases (53.3%) and remained the same in six (40%) cases. For the right eye (OD), the MGL% was 0.46 ± 0.08 at baseline, which decreased to 0.32 ± 0.07 at six months. For the left eye (OS), MGL% was 0.52 ± 0.09 at baseline, and at six months, it reduced to 0.34 ± 0.08. In OD, MGL% was 0.46 ± 0.06 at baseline, reduced to 0.35 ± 0.12 at six months. In OS, MGL% was 0.49 ± 0.09 at baseline, and at six months, it reduced to 0.35 ± 0.12. In the IPL group, the mean TBUT in OD improved from 3.25 to 5.25 in 1 month. The mean TBUT for OS improved from 4.19 to 6.44 in OS. In the IPL+LLLT group, the mean TBUT in OD improved from 3.2 to 5.2 at one month in OS. The mean TBUT in OS improved from 4.27 to 6 in one month. Conclusion: IPL alone or in combination with LLLT has similar efficacy in treating MGD. There was a reduction in the OSDI score LOD with improved TBUT and decreased MGL% at the end of 1, and six months.

Blood-Derived Eye Drops for the Treatment of Corneal Neuropathic Pain.

Blood-derived preparations, including autologous or allogenic serum, umbilical cord serum/plasma, and platelet-rich plasma eye drops, contain various growth factors, cytokines, and immunoglobulins that resemble natural tears. These components play important roles in corneal cell migration, proliferation, and wound healing. Blood-derived eye drops have demonstrated clinical effectiveness across a spectrum of ocular surface conditions, encompassing dry eye disease, Sjögren's syndrome, graft-versus-host disease, and neuropathic corneal pain (NCP). Currently, management of NCP remains challenging. The emergence of blood-derived eye drops represents a promising therapeutic approach. In this review, we discuss the benefits and limitations of different blood-derived eye drops, their mechanisms of action, and treatment efficacy in patients with NCP. Several studies have demonstrated the clinical efficacy of autologous serum eye drops in relieving pain and pain-like symptoms, such as allodynia and photoallodynia. Corneal nerve parameters were also significantly improved, as evidenced by increased nerve fiber density, length, nerve reflectivity, and tortuosity, as well as a decreased occurrence of beading and neuromas after the treatment. The extent of nerve regeneration correlated with improvement in patient-reported photoallodynia. Cord plasma eye drops also show potential for symptom alleviation and corneal nerve regeneration. Future directions for clinical practice and research involve standardizing preparation protocols, establishing treatment guidelines, elucidating underlying mechanisms, conducting long-term clinical trials, and implementing cost-effective measures such as scaling up manufacturing. With ongoing advancements, blood-derived eye drops hold promise as a valuable therapeutic option for patients suffering from NCP.

Melanocytic ocular surface squamous neoplasia successfully managed with no-touch excisional biopsy, cryotherapy and amniotic membrane transplantation.

Melanocytic ocular surface squamous neoplasia successfully managed with no-touch excisional biopsy, cryotherapy and amniotic membrane transplantation.

Expression of CD44, PCNA and E-cadherin in pterygium tissues.

Pterygium is a common ocular surface disease defined by fibrovascular conjunctival growth extending onto the cornea. However, its pathogenesis remains unclear. This study aimed to determine the role of CD44, proliferating cell nuclear antigen (PCNA), and E-cadherin in pterygium formation and recurrence. Sixty patients with pterygium participated in the study, and we collected conjunctival samples from 30 patients to form a control group. CD44, PCNA, and E-cadherin expressions in surgically excised pterygium were compared with tissue samples from the control group. We observed that the percentages of CD44 and PCNA were statistically higher in the primary pterygium group and recurrent pterygium group than in the control group (P < 0.001 and P < 0.001, respectively). Conversely, E-cadherin values were statistically higher in the control group than in the primary and recurrent pterygium groups (P = 0.013 and P < 0.001, respectively). Cell proliferation and cell adhesion factors may play important roles in the pathogenesis of pterygium.

Cytisine eye drops for benzalkonium chloride-induced dry eye: safety and efficacy evaluation

This experiment aimed to investigate the feasibility of cytisine (CYT) in treating eye diseases with ocular topical application. An in vitro cytotoxicity test, a hen’s egg test-chorioallantoic membrane (HET-CAM), and a mouse eye tolerance test were used to fully reveal the ocular safety profiles of CYT. For the efficacy evaluations, CYT’s effects on cell wound healing, against H2O2-induced oxidative stress damages on cells, and on benzalkonium chloride (BAC)–induced dry eye disease (DED) in mice were evaluated. Results showed that CYT did not show any cytotoxicities at concentrations no higher than 250 μg/ml, while lipoic acid (α-LA) at 250 μg/ml and BAC at 1.25 μg/ml showed significant cytotoxicities within 48 h incubation. The HET-CAM and mouse eye tolerance test confirmed that 0.5% CYT eye drops demonstrated good safety characteristics. Efficacy evaluations showed that CTY significantly promoted cell migration and wound healing. CYT significantly improved cell survival against H2O2-induced oxidative stress damage by reversing the imbalance between the reactive oxygen species (ROS) and antioxidant defense mechanisms. The animal evaluation of the BAC-induced dry eye model revealed that CYT demonstrated a strong treatment effect, including reversing ocular surface damages, recovering corneal sensitivity, and inhibiting neovascularization; HMGB1/NF-κB signaling was involved in this DED treatment by CTY. In conclusion, CYT had strong experimental treatment efficacy against DED with good ocular safety profiles, and it might be a novel and promising drug for DED.

Dexamethasone sodium phosphate loaded nanoparticles for prevention of nitrogen mustard induced corneal injury

Nitrogen mustard (NM) is a potent vesicating chemical warfare agent that is primarily absorbed through skin, inhalation, or ocular surface. Ocular exposure of NM can cause acute to chronic keratopathy which can eventually lead to blindness. There is a current lack of effective countermeasures against ocular exposure of NM despite their imperative need. Herein, we aim to explore the sustained effect of Dexamethasone sodium phosphate (DSP)-loaded polymeric nanoparticles (PLGA-DSP-NP) following a single subconjunctival injection in the management and prevention of corneal injury progression upon exposure to NM. DSP is an FDA approved corticosteroid with proven anti-inflammatory properties. We formulated PLGA-DSP-NP with zinc chelation ion bridging method using PLGA polymer, with particles of approximately 250 nm and a drug loading of 6.5 wt%. Under in vitro sink conditions, PLGA-DSP-NP exhibited a sustained drug release for two weeks. Notably, in NM injured cornea, a single subconjunctival (SCT) injection of PLGA-DSP-NP outperformed DSP eyedrops (0.1%), DSP solution, placebo NP, and saline, significantly mitigating corneal neovascularization, ulceration, and opacity for the two weeks study period. Through PLGA-DSP-NP injection, sustained DSP release hindered inflammatory cytokine recruitment, angiogenic factors, and endothelial cell proliferation in the cornea. This strategy presents a promising localized corticosteroid delivery system to effectively combat NM-induced corneal injury, offering insights into managing vesicant exposure.

Evidence for persistent UV-induced DNA damage and altered DNA damage response in xeroderma pigmentosa patient corneas

Xeroderma pigmentosum (XP) is a rare genetic disorder characterized by injury to the ocular surface due to exposure to ultraviolet (UV) radiation. UV-induced damage in the cells leads to the formation of cyclobutane pyrimidine dimers (CPDs) and 6-4 pyrimidine-pyrimidone photoproducts that are repaired by the NER (Nucleotide Excision Repair) pathway. Mutations in the genes coding for NER proteins, as reported in XP patients, would lead to sub-optimal damage repair resulting in clinical signs varying from photo-keratitis to cancerous lesions on the ocular surface. Here, we aimed to provide evidence for the accumulation of DNA damage and activation of DNA repair pathway proteins in the corneal cells of patients with XP. Corneal buttons of patients who underwent penetrating keratoplasty were stained to quantify DNA damage and the presence of activated DNA damage response proteins (DDR) using specific antibodies. Positive staining for pH2A.X and thymidine dimers confirmed the presence of DNA damage in the corneal cells. Positive cells were found in both control corneas and XP samples however, unlike normal tissues, positive cells were found in all cell layers of XP samples indicating that these cells were sensitive to very low levels of UV. pH2A.X-positive cells were significantly more in XP corneas (p < 0.05) indicating the presence of double strand breaks in these tissues. A positive expression of phosphorylated-forms of DDR proteins was noted in XP corneas (unlike controls) such as ataxia telangiectasia mutated/Rad-3 related proteins (ATM/ATR), breast cancer-1 and checkpoint kinases-1 and -2. Nuclear localization of XPA was noted in XP samples which co-localized (calculated using Pearson's correlation) with pATM (0.9 ± 0.007) and pATR (0.6 ± 0.053). The increased presence of these in the nucleus confirms that unresolved DNA damage was accumulating in these cells thereby leading to prolonged activation of the damage response proteins. An increase in pp53 and TUNEL positive cells in the XP corneas indicated cell death likely driven by the p53 pathway. For comparison, cultured normal corneal epithelial cells were exposed to UV-radiation and stained for DDR proteins at 3, 6 and 24 h after irradiation to quantify the time taken by cells with intact DDR pathway to repair damage. These cells, when exposed to UV showed nuclear translocation of DDR proteins at 3 and 6 h which reduced significantly by 24 h confirming that the damaged DNA was being actively repaired leading to cell survival. The persistent presence of the DDR proteins in XP corneas indicates that damage is being actively recognized and DNA replication is stalled, thereby causing accumulation of damaged DNA leading to cell death, which would explain the cancer incidence and cell loss reported in these patients.

Dry eye rate and its relationship with disease stage in patients with primary hypertension: a cross-sectional study in Vietnam.

To determine the dry eye (DE) rate and its relationship with disease stage in patients with primary hypertension. A cross-sectional study included 432 patients with primary hypertension (with an equal number of patients in each group: 144 in stage I, II, and III hypertension) and 144 healthy subjects as a control group. The Ocular Surface Disease Index (OSDI) and Schirmer I test without anesthetics were conducted on all 576 subjects. Subjects with OSDI scores <13 and Schirmer I values equal to or under 10 mm were diagnosed with DE. The ratio of DE in hypertension patients was higher than in the control group (41.7% versus 18.8%; P<0.001). The proportion of patients with DE increased gradually according to the hypertension stage: 27.1% in stage I, 40.3% in stage II, and 57.6% in stage III, P<0.001. Age, duration of hypertension, plasma urea, creatinine, and high-sensitivity C-reactive protein (CRP-hs) levels in hypertension patients with DE were higher than those without DE, P<0.001. Advanced age, a long duration of hypertension, diabetes mellitus, elevated plasma creatinine, and CRP-hs levels were independent factors associated with DE in primary hypertension patients, P<0.001. DE is a common disorder associated with advanced age, a long duration of hypertension, diabetes mellitus, elevated plasma CRP-hs, and creatinine levels in patients with primary hypertension.

Assessment of tear film parameters post-treatment with commercial eyelid cleaning wipes: a pilot study.

To investigate the short-term effects of commercially available eyelid-cleaning wipes on film parameters. This study enrolled 48 healthy participants aged 20-35y (both males and females). Clinical assessment included the Ocular Surface Disease Index (OSDI) questionnaire, non-invasive tear break-up time (NITBUT), tear meniscus height (TMH), and lipid layer pattern (LLP). Based on these initial results, participants were categorized as either non-dry eye or dry eye. Participants in each group were randomly allocated to either Blephaclean® or Systane® treatments. Changes in NITBUT, TMH, and LLP levels before and after lid wipe treatment were assessed. The dry eye group exhibited significantly higher OSDI scores and lower NITBUT and TMH levels than in the non-dry eye group (P<0.001). Following the application of eyelid wipes (Systane® wipes), dry eye subjects experienced a significant improvement in NITBUT levels (P=0.0014) compared to the non-dry eye individuals. Although the remaining participants showed a marginal increase in TMH and NITBUT levels, these changes did not achieve statistical significance (P>0.05). Similarly, the LLP levels were significantly improved with Systane® (P<0.001) post-treatment compared to individuals in the non-dry eye group. However, the dry eye subjects showed higher post-treatment LLP levels than the untreated group (P<0.02). The short-term effects of Systane® eyelid wipes on tear film parameters suggest their effectiveness in dry eye disease. Nonetheless, further exploration of their long-term impact is essential to justify their cost effectiveness and efficacy in treating both aqueous deficiency and evaporative dryness.

Trends and Clinical Outcomes of Fungal Keratitis in Canada: a 20-year Retrospective Multicentre Study

PurposeAn increase in fungal and particularly filamentous keratitis has been observed in many geographic areas, mostly in contact lens wearers. This study seeks to characterize long-term trends in fungal keratitis in a continental climate area to provide guidance for diagnosis and treatment. DesignRetrospective multicentric case series. MethodsCases of microbiology-confirmed fungal keratitis from 2003 to 2022 presenting to tertiary care centers across Canada were included. Charts were reviewed for patient demographics, risk factors, visual acuity, and treatments undertaken. ResultsA total of 138 patients were identified: 75 had yeast keratitis while 63 had filamentous keratitis. Patients with yeast keratitis had more ocular surface disease (79% vs 28%) while patients with filamentous keratitis wore more refractive contact lenses (78% vs 19%). Candida species accounted for 96% of all yeast identified, while Aspergillus (32%) and Fusarium (26%) were the most common filamentous fungi species. The mean duration of treatment was 81 ± 96 days. Patients with yeast keratitis did not have significantly improved visual acuity with medical treatment (1.8 ± 1 LogMAR to 1.9 ± 1.5 LogMAR, p = 0.9980), in contrast to patients with filamentous keratitis (1.4 ± 1.2 LogMAR to 1.1 ± 1.3 LogMAR, p = 0.0093). ConclusionsFungal keratitis is increasing in incidence, with contact lenses emerging as one of the leading risk factors. Significant differences in the risk factors and visual outcomes exist between yeast keratitis and filamentous keratitis which may guide diagnosis and treatment.

RIPK3 and RIPK1 gene expression in pterygium: unveiling molecular insights into pathogenesis.

Pterygium, characterized by the abnormal proliferation of epithelial cells, matrix remodeling, vascularization, and lesion migration, is a prevalent ocular surface disease involving the growth of fibrovascular tissue on the cornea. Despite the unclear underlying causes of pterygium, numerous investigations have indicated the involvement of cell death pathways in the regulation of cell cycle dynamics. Consequently, the objective of this study was to assess the expression levels of necroptosis markers in individuals diagnosed with pterygium, aiming to shed light on the potential role of necroptosis in the pathogenesis of this condition. This study aimed to investigate the expression patterns of receptor-interacting serine/threonine kinase 3 (RIPK3) and receptor-interacting serine/threonine kinase 1 (RIPK1) genes in pterygium tissues. 41 patients undergoing pterygium excision surgery were recruited. Resected pterygium samples and normal conjunctival tissues were collected, and RIPK3 and RIPK1 mRNA levels were measured using quantitative real-time PCR. Our findings reveal that the expression of RIPK3 is significantly increased in samples obtained from individuals with pterygium. However, no significant alterations were observed in the expression of RIPK1 in these samples. Results showed significantly higher RIPK3 expression in pterygium tissues compared to controls. Moreover, increased RIPK3 levels correlated negatively with pterygium recurrence rates. These findings suggest RIPK3 may play a protective role against pterygium recurrence through necroptosis.

Mimicking the Physicochemical Properties of the Cornea: A Low-Cost Approximation Using Highly Available Biopolymers.

Corneal diseases represent a significant global health challenge, often resulting in blindness, for which penetrating keratoplasty is the clinical gold standard. However, in cases involving compromised ocular surfaces or graft failure, osteo-odonto keratoprosthesis (OOKP) emerges as a vital yet costly and complex alternative. Thus, there is an urgent need to introduce soft biomaterials that mimic the corneal tissue, considering its translation's physicochemical, biological, and economic costs. This study introduces a cross-linked mixture of economically viable biomaterials, including gelatin, chitosan, and poly-D-lysine, that mimic corneal properties. The physicochemical evaluation of certain mixtures, specifically gelatin, chitosan, and poly-D-lysine cross-linked with 0.10% glutaraldehyde, demonstrates that properties such as swelling, optical transmittance, and thermal degradation are comparable to those of native corneas. Additionally, constructs fabricated with poly-D-lysine exhibit good cytocompatibility with fibroblasts at 72 h. These findings suggest that low-cost biopolymers, particularly those incorporating poly-D-lysine, mimic specific corneal characteristics and have the potential to foster fibroblast survival. While further studies are required to reach a final corneal-mimicking solution, this study contributes to positioning low-cost reagents as possible alternatives to develop biomaterials with physicochemical properties like those of the human cornea.

Lacrimal occlusion and anti-inflammation with dexamethasone microcrystals incorporated gelatin methacryloyl-based plugs for treatment of dry eye

Dry eye, a frequently encountered disease of the ophthalmic clinic, is characterized by tear deficiency and ocular surface inflammation. Tear preservation through lacrimal drainage system plugs and anti-inflammatory therapy with glucocorticoids are generally used separately to control the disease progression. However, inherent limitations of current available plugs have necessitated the pursuit of new materials for plug production. Meanwhile, the therapeutic effects of glucocorticoids have been compromised by frequent dosing which reduces patient compliance. To address this, our present study developed a dexamethasone eluting intracanalicular plug (DEX-Plug) with dexamethasone microcrystals (DEX MCs) and gelatin methacryloyl (GelMA), which treated dry eye by simultaneous lacrimal occlusion and anti-inflammation. The resultant plug was biodegradable, biocompatible, and swelled rapidly to adapt the irregular anatomical structure of lacrimal canaliculi. It can block the lacrimal drainage system while serving as a drug delivery vehicle for sustained release of dexamethasone. The dual-functional therapeutic effects of DEX-Plug were demonstrated in a rabbit dry eye model using lissamine green drainage rates, the Schirmer’s test, corneal fluorescein staining, and real-time PCR. The plug reported herein can also be harnessed to deliver drugs other than dexamethasone, thus providing a novel approach to improve the treatment of dry eye.