Bulbar Conjunctiva Research Articles

Vernal Keratoconjunctivitis in Sudan and Its Impact on Visual Acuity

Purpose: Despite being a self-limiting allergy disorder, vernal keratoconjunctivitis (VKC) can potentially cause severe problems, including blindness, if not properly treated. Therefore, the objective of this study is to determine the effect of VKC on the visual acuity of patients. Materials and Methods: We conducted this prospective descriptive study between January 1, 2023, and April 20, 2024.So, all children with spring catarrh symptoms and signs were examined at Dr. Khalil's ophthalmology center (240 patients), including the cornea, bulbar, and palpebral conjunctiva, visual acuity was measured, visual impairment was classified by WHO, and structured questionnaires were completed. The study excludes children under the age of four years and those over the age of eighteen years. Findings: A total of 240 patients participated in this assessment, with an average age of 10 years. The male to female ratio for the age of disease beginning was 2.10:100. The mean age of onset was 5 years. The occurrence of this phenomenon is more prevalent in the younger age group compared to the older age group, with a ratio of 1.40 to 1.00. We have observed that a condition recurs in 85% of patients. The illness affects both eyes in 97% of the individuals. Regarding visual acuity, the majority of patients exhibit normal or reduced visual acuity, accounting for 81.6%, while the remaining 15% experience substantial visual impairment. 2.1% of patients were found to have severe visual impairment, while 1.3% were diagnosed Implications to Theory, Practice and Policy: VKC, is a prevalent disease in Sudan. It often affects both eyes and is more common in males than females. VKC tends to occur at a young age and often recurs in patients. Additionally, it can lead to severe consequences that result in a decline in visual acuity in over 18% of patients. Children with VKD should undergo continuous screening for their visual acuity.

Substantiation of pharmacological correction of the condition of the ocular surface in postcovid syndrome

Substantiation of pharmacological correction of the condition of the ocular surface in postcovid syndrome

Ocular manifestations in patients with autoimmune bullous dermatoses: A hospital-based retrospective study

Background: Ocular involvement in autoimmune bullous dermatoses (AIBD) remains underappreciated. Objectives: The objective was to study the prevalence and characteristics of ocular involvement in patients with AIBD. Methods: The medical records of 25 patients (males: females 11:14) aged between 27 and 85 years (mean ± standard deviation = 44.9 ± 15.6 years) with AIBD were analyzed retrospectively for clinico-epidemiological attributes and the presence of ocular abnormalities. Results: There were 20 (80%) pemphigus patients, of which most were pemphigus vulgaris (PV, n = 14) and pemphigus foliaceus (PF, n = 6). Other 5 (20%) patients included bullous pemphigoid (BP, n = 4) and cicatricial pemphigoid (CP, n = 1). Seventeen (68%) patients comprising 11 (78.6%) of PV, 3 (50%) of PF, 2 (50%) of BP, and 1 (100%) of CP had 27 ocular abnormalities. Erosions of lid margins (n = 3, 27.3%), blepharitis with meibomitis (n = 1, 9.1%), chalazion (n = 1, 9.1%), and conjunctival vesicles over bulbar conjunctivae (n = 2, 18.2%), conjunctivitis (PV = 5, 45.5%, PF = 1, 33.3%), and symblepharon and keratoconjunctivitis sicca in one (9.1%) patient each, respectively, were major ocular manifestations in pemphigus. Entropion with trichiasis, shallow fornices, and corneal opacities were major abnormalities in patients with BP (n = 2, 100%) and CP (n = 1, 100%). Conclusion: Ocular comorbidities vary in prevalence and severity between subtypes of AIBD. These are mainly from complications of ocular surface disease predominantly affecting the anterior segment of the eye. They are more severe in patients with CP compared to others. The study is limited by a single-center, retrospective-study design, a small number of patients in each group for stratification, and long-term follow-up.

Ocular Drug Delivery into the Eyes Using Drug-Releasing Soft Contact Lens

The impact of visual impairment, such as blindness, on quality of life is immeasurable. However, effective ocular drug delivery into the eyes has not yet been established, primarily due to the impermeability imposed by the blood–retinal barrier (BRB) based on the tight junctions and efflux transporters at the endothelium or the epithelium in oral or intravenous administration, as well as the dilution with tear fluid and excretion through the nasolacrimal duct in eye drop administration. Furthermore, intravitreous injections induce pain and fear in patients. Unmet medical needs persist in ocular diseases such as age-related macular degeneration and diabetic retinopathy. Therefore, innovative non-invasive administration methods should be developed. Drug-releasing soft contact lenses (DR-SCLs) affixed to the eye’s surface can continuously and locally deliver their loaded drugs to the eyes. The use of DR-SCLs is expected to greatly enhance the bioavailability and patient adherence to the drug regimen. It is known that several solute carrier (SLC) transporters are expressed in various parts of the eyes, including the cornea, the ciliary body, and the bulbar conjunctiva. Carrier-mediated transport through SLC transporters may occur in addition to passive diffusion. Moreover, nanoparticles can be loaded into DR-SCLs, offering various intelligent approaches based on modifications to induce receptor-mediated endocytosis/transcytosis or to control the loaded drug release within this delivery system. In this perspective review, I discuss the implementation and potential of DR-SCL-mediated ocular drug delivery, particularly focusing on low-molecular-weight compounds because of their fine distribution in living body, ease of handling, and ease of manufacturing.

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.

Efficacy, safety and cost-effectiveness of 5-fluorouracil versus interferon α-2b as adjuvant therapy after surgery in ocular surface squamous neoplasia in a southern European tertiary hospital.

To analyze the efficacy, safety and cost-effectiveness of adjuvant therapy with 5-fluorouracil (5-FU) compared to interferon α-2b (IFNα-2b) after surgery in ocular surface squamous neoplasia (OSSN). Retrospective study that included patients diagnosed with OSSN, who underwent surgical excision followed by adjuvant therapy with IFN α-2b (Group A) or 5-FU (Group B), in a tertial referral hospital. Clinical data collected included: demographics, risk factors, appearance, size and location of the lesions, slit-lamp examination, anterior segment optical coherence tomography, iconography and histological classification of subtypes of OSSN. Costs derived from surgery and adjuvant therapy were noted. Resolution of the lesion, recurrences and adverse events were studied. Cost-effectiveness analysis was performed with the incremental cost-effectiveness index (CEI). 54 cases of 54 patients were included, with a mean age of 74.4years (range 28-109). 30 were male (55.6%), and predominantly Caucasian (79.6%). The main risk factor was prolonged sun exposure (79.6%). Leukoplakic appearance (48.1%), location in bulbar conjunctiva (48.2%) and T3 (46.3%) stage were the most common clinical features. Histologically, the percentage of CIN I, CIN II, CIN III and SCC were 25.9%, 29.6%, 40.7% and 3.7%, respectively. Complete resolution was obtained in 74.1% and tolerance was overall positive. The cost was significantly higher for IFNα (1025€ ± 130.68€) compared to 5-FU (165.57€ ± 45.85€) (p 0.001). The CEI was - 247.14€. Both 5-FU and IFN α-2b are effective and present a good security profile as adjuvant therapies after surgery in OSSN. Although presenting slightly more ocular complications, 5-FU can be considered more cost-effective than IFN α-2b.

Rehabilitation program of post-COVID-19 syndrome with the use of nitric oxide and molecular hydrogen

To evaluate the safety and efficacy of the combined inhalation of NO and H2 (iNO/iH2) in patients with respiratory manifestations of PS. 34 patients with PS (11 men/23 women, 60.0±11.7 years) were included in the prospective open-label controlled study in parallel groups: the main group (n=17) received iNO/iH2 for 90 minutes once a day for 10 days (concentration of NO 60 ppm, H2<4% in the gas mixture), the control group (n=17) didn't receive inhalations. The period from the confirmation of COVID-19 to the start of the study was 641.8±230.5 days. The groups did not differ in the baseline parameters. The clinical symptoms (from the self-observation diary and mMRC questionnaires, "dyspnea language"), FAS, HADS, SF-36 scores, 6-minute walk test, the blood serum parameters of oxidative stress, the dynamics of the microcirculation in the eye bulbar conjunctiva were evaluated. The individual dose of iNO has chosen during a 15-minute test (the positive dynamics of the microcirculation have indicated that the dose was selected correctly). The decrease the symptoms severity, such as dyspnea, cough, fatigue and palpitations (p<0.005), the increase in SF-36 questionnaire scores (p=0.006) and a reducing of FAS score (p=0.001), as well as the anxiety component of HADS (p=0.02) were revealed at the end of treatment in the main group compared to the control group. We observed an improvement in distance walked (p=0.01) and the values SpO2 (p=0.04) in 6-minute walk test, the increase in the volumetric blood flow velocity in venules (p<0.001), and the date in oxidative damage (p<0.001) and antioxidant activity (p=0.03) parameters in the blood serum. The results of the study demonstrate clinical efficacy iNO/iH2 on clinical indicators, parameters of oxidative stress and microcirculation in patients with PS.

Uncommon case of isolated conjunctival histoplasmosis: A rare clinical entity

We report an unusual case of isolated conjunctival histoplasmosis in a healthy immunocompetent patient. A 62-year-old male presented with a gradually progressing, painless, fleshy mass in both eyes for 2 months. On examination, a diffuse, raised, vascularized, and nontender mass was noted on the entire bulbar conjunctiva. On incisional biopsy, the histopathologic report confirmed a causative agent of Histoplasma capsulatum. He was then treated with topical itraconazole and intravenous amphotericin B, the lesion exhibited signs of regression. When confronted with an unusual conjunctival mass, it is imperative to do a detailed microbiological and histopathological work-up of a patient.

Diabetic Ocular Surface Has Defects in Oxygen Uptake Revealed by Optic Fiber Microsensor.

Diabetes mellitus causes diabetic keratopathy (DK). This and other ocular surface disorders are underdiagnosed and problematic for affected patients as well as recipients of diabetic donor corneas. Thus, it is important to find noninvasive means to facilitate determination of the potentially vision-threatening DK. It has been reported that diabetic corneas uptake significantly less oxygen (O2) than healthy controls. However, an integral assessment of the ocular surface is missing. Using an optic-fiber O2 micro-sensor (optrode) we demonstrated recently that the healthy ocular surface displays a unique spatiotemporal map of O2 consumption. We hypothesize that diabetes impairs the spatiotemporal profile of O2 uptake at the ocular surface. Using streptozotocin (STZ)-induced diabetic mice, we found diminished O2 uptake and loss of the unique pattern across the ocular surface. A diabetic cornea consumes significantly less O2 at the bulbar conjunctiva and limbus, but not the central and peripheral cornea, compared to controls. Further, we show that, contrary to the healthy cornea, the diabetic cornea does not increase the O2 consumption at the limbus in the evening as the normal control. Altogether, our measurements reveal a previously unknown impairment in O2 uptake at the diabetic cornea, making it a potential tool to diagnose ocular surface abnormalities and suggesting a new etiology mechanism.

Primary third eyelid lymphoma with aggressive local behavior in a dog

Lymphoma is the most common hematopoietic neoplasm in dogs. However, cases primarily involving the third eyelid are rarely reported in the species. The subtype most frequently described in this location is marginal zone lymphoma of the mucosa-associated lymphoid tissue, which has an indolent behavior. A 10-year-old intact female Poodle was presented with a 2-month history of a nodule in the left third eyelid for evaluation. This nodule was surgically excised; however, local recurrence was detected nineteen days postoperatively, with the formation of a mass that expanded and replaced the extraocular orbital tissues and infiltrated the eye. Euthanasia was elected due to the deteriorating clinical condition, and a necropsy was performed. Macroscopically, the mass infiltrated and expanded the eyelids with narrowing of the palpebral fissure, expanded into the orbital space, and infiltrated the cornea and bulbar conjunctiva. Histologically, the mass was composed of sheets of intermediate to large neoplastic lymphocytes, with frequent epitheliotropism and tingible bodies. Neoplastic lymphocytes were immunoreactive for PAX5, CD20, and CD79a and were not immunoreactive for CD3. The neoplasm was restricted to the left eyelid and orbit. A diagnosis of primary third eyelid lymphoma (extranodal) with immunophenotype B and locally aggressive behavior was made based on the macroscopic, histological, and immunohistochemical findings.

A prospective comparative study of conjunctival autograft (CAG) with dry amniotic membrane graft (AMG) transplantation in pterygium excision surgery

: Pterygium is a wing-shaped, fibrovascular proliferation of the bulbar conjunctiva which crosses the limbus and causes encroachment over the cornea. It is mainly treated by surgical excision. Management options for pterygium include conjunctival autografting, and the use mitomycin C, amniotic membrane graft, 5-fluorouracil, anti-vascular endothelial growth factor (anti-VEGF) agents, and β-irradiation along with excision, to avoid recurrence.: To compare the efficacy and safety of conjunctival autograft (CAG) transplantation and dry amniotic membrane graft (AMG) transplantation in pterygium excision surgery.: Prospective comparative study.: The study was done on 43 eyes of 43 patients. CAG was transplanted on 23 patients &amp; dry AMG was transplanted on 20 patients. All patients were followed up on day 1, day 7, 1 month and 6 months post operatively. On each visit pterygium recurrence, graft retraction, necrosis and visual outcomes were noted from all the patients.: Fisher exact test.: 28(65%) were males while 15(35%) were females. Most of the patients were &amp;#60;40 years of age. During the follow up period, best corrected visual acuity of 3(7%) patients remained same and improved in 40(93%) patients. CAG group had 2(8.69%) while dry AMG group had 4(20%) recurrences (p value = 0.39, non-significant).: Although both the groups showed low recurrence rate but recurrence rate was more in dry AMG group as compared to conjunctival autograft group.: AMG is not always the best option for treating pterygium, but in some situations—such as those with extensive pterygium, conjunctival scarring etc.—it may be more advantageous for the patient.

The state of central and peripheral hemodynamics in patients with out-of-hospital pneumonia associated with subclinical hypothyroidism

Objective: to investigate the state of сеntral and peripheral hemodynamics in patients with out-of–hospital pneumonia (OHP) combined with subclinical hypothyroidism (SH). Materials and methods: the study was conducted in 132 patients with OHP of clinical groups II-III, including 64 with OHP combined with SН — the main group, and 68 with OHP without SН (comparison group). The average age of the patients was 37.4±3.3 years, including 74 women among the studied, 58 men. The state of microcirculation in patients was studied by biomicroscopy of the bulbar conjunctiva using a slit lamp with the calculation of conjunctival indices, intravascular aggregation of shaped blood elements was observed in the presence of a sludge phenomenon according to N. Knisely (1965), and central cardiohemodynamics parameters were determined. Results: in patients with OHP, along with small clinical signs of hypertension, laboratory data were revealed: TSH — (6,4±0,6) мIU/ml, free T4 — (13,2±1,1) pmol/L, the level of ATP — 53,7±2,3 IU/ml — microcirculatory disorders with changes in the microvascular wall, sludge in them, perivascular changes, as well as dysfunction of the right and left ventricles of the heart. Conclusions: the combination of OHP and SH in patients is accompanied by significant microvascular shifts, which are associated with disorders of central cardiohemodynamics in the form of dysfunction of the right and left ventricles of the heart. The found correlations between the parameters of cardiohemodynamics and microcirculation in patients with OHP combined with SH and TSH levels confirm the negative effect of subclinical hypothyroidism on the state of central and peripheral hemodynamics in patients.

Shave Excision Of Marginal Lower Eyelid Nevus

Introduction : INTRODUCTION: Nevus is a common benign melanocytic lesion and may appear in palpebral region. It may appear congenitally or acquired. Such lesions contain melanocyte derived from neural crest. Palpebral nevus is a group of heterogenous lesion with varying clinical and histological presentation depending on age and nevus stage. PURPOSE: To report shave excision procedure of the left inferior palpebral nevus located in the palpebral margin using local anesthesia.&#x0D; Case Illustration : CASE REPORT: A 43-years old woman came to the hospital with a solitary mass in the lower right eyelid. The mass was experienced since 2 year ago and slowly increasing in size and most notably 3 months prior. The mass was round, tender, painless, black-greyish colored, with a smooth surface, mobile, and measured 0,5 cm x 0,5 cm in size. The lesion was located in the middle portion of right lower palpebral margin without extension to the tarsal or bulbar conjunctiva. No bleeding or discharge was found. No history of trauma, use of medication, family history, previous ocular and systemic disease was found. Histopathological examination concluded the lesion was nevus pigmentosus. The nevus was excised entirely using shave excision technique with local anesthesia. Follow-up examination revealed an excellent result with no complications.&#x0D; Discussion : &#x0D; Conclusion : CONCLUSION: Palpebral nevus pigmentosus are common benign tumor with wide range of clinical and histological manifestation. Not all palpebral nevus required surgical intervention. The most effective treatment is complete excision of the nevus and recurrence rate is generally low.

A Case: The Strategy of Corneal Ulcers

Introduction : Corneal ulcers are considered an ophthalmologic emergency because of their potential to permanently impair vision or perforate the eye. Accurate and quick diagnosis and prompt treatmentis a key to improve clinical and visual outcomes in cases of corneal ulceration.&#x0D; Case Illustration : In this paper, we present the case of male 40-year-old presented with complaints of pain and defective vision in the right eye. Visual examination of the right eye is 1/~. It was found, palpebral edema, hyperemic tarsal conjunctiva. The bulbar conjunctiva showed conjunctival injection, ciliary injection. The cornea looks completely cloudy, the surface is not slippery, infiltrates and edema. The patient was treated with medical and surgical therapy, and then the patient’s have a good clinical response and was able to return to work.&#x0D; Discussion : The diagnosis of corneal ulcers was established based on history, physical examination and clinical examination using a slit lamp and laboratory examinations. Patient's examination revealed the presence of Candida albicans. This examination is important to distinguish the cause of the corneal ulcer so that it can help select an adequate therapy.&#x0D; Conclusion : Indonesian farmers have highrisk of fungal corneal ulcers. Fungal corneal ulcers is important cause of corneal blindness all over the world especially in develoving countries. Fungal corneal ulcers can diagnosis by slitlamp biomicroscopic examination and culture are essential for early specific diagnosis and must be taken consideratiaon to establish the most effective treatment and avoid severe complications

High-throughput screening of transient receptor potential (TRP) channels in pterygium.

Pterygium is a hyaline degenerative disease of the conjunctiva characterized by the progression of fibrovascular connective tissue from the bulbar conjunctiva to the cornea. The mechanism of pterygium formation is still not fully understood. Transient receptor potential (TRP) channels are a group of ion channels with distinct characteristics. Recent indications suggest TRP channels may play a significant regulatory role in pterygium development, but previous studies have mainly focused on in silico analysis. Accordingly, in the present study, we aimed to decipher the expression signatures and role of TRP channels in pterygium development. The study encompassed a cohort of 45 patients matched for age and gender distribution, comprising 30 individuals with primary pterygium (PP) and 15 individuals with recurrent pterygium(RP). The control group consisted of unaffected conjunctival tissue obtained from the same set of patients. High-throughput screening of differentially expressed TRP channels in pterygium tissues was achieved with the help of Fluidigm 96.96 Dynamic Array Expression Chip and reactions were held in BioMark™ HD System Real-Time PCR platform. Statistically significant increases were found in the expression of 21 genes, mainly TRPA1 (p = 0.021), TRPC2 (p = 0.001), and TRPM8 (p = 0.003), in patients with PP, and in TRPC5 (p = 0.05), TRPM2 (p = 0.029), TRPM4 (p = 0.03), TRPM6 (p = 0.045), TRPM8 (p = 0.038), TRPV1 (p = 0.01) and TRPV4 (p = 0.025) genes in RP tissues. Collectively, TRP channel proteins appear to play pivotal roles in both the development and progression of pterygium, making them promising candidates for future therapeutic interventions in patients afflicted by this condition.

Incidence Of Photokeratitis In Factory Workers After Ultraviolet C Exposure and Its Management : A Case Series

Introduction : Ultraviolet C lamps have been used in industry and healthcare to disinfect rooms, air, water, and surfaces. However, exposure to UV-C may cause serious damage to human eyes.&#x0D; Case Illustration : This were photokeratitis case series of 4 factory workers that occurred simultaneously after 4 hours exposure to UV-C lamp about one meter away without any protective eyewear. Several hours after exposure, they complained swollen, red and watery eyes, photophobia, sandy sensation, and blurry vision. One day after, they were taken to the Emergency Unit. Diagnosis of photokeratitis was established by using biomicroscopic examination. All subjects were treated with antibiotic eye drops, lubricants, oral anti-inflammatory drugs, and cold compress. Evaluation after 1 week showed clinical improvement and all subjects were able to return to work normally.&#x0D; Discussion : Photokeratitis or ultraviolet keratitis is an inflammatory condition of the cornea after ultraviolet exposure for 30 minutes to 12 hours. The corneal epithelial layer functions as protector for corneal stroma and endothelium. However, the longer corneal epithelium is exposed to ultraviolet light, the more damaged it is. This caused subepithelial nerve plexus exposed, resulting in severe pain, photophobia, and bilateral epiphora. Injection and chemosis of bulbar conjunctiva, epiphora, and punctate keratopathy of cornea were found in examination. The management given is supportive therapy, and should be immediately given until corneal epithelium healed.&#x0D; Conclusion : Photokeratitis may occurred in daily work. Regulation, warning, training and appropriate protective eyewear for workers in workplaces using UV-C lamps are mandatory. Immediate and adequate treatment can save the sight of workers exposed to UV-C.

Characterizing the Robustness of Distinct Clinical Assessments in Identifying Dry Eye Condition of Animal Models

Purpose The study aims to characterize the robustness of distinct clinical assessments in identifying the underlying conditions of dry eye disease (DED), with a specific emphasis on the involvement of conjunctival goblet cells. Methods Seven rabbits receiving surgical removal of the lacrimal and Harderian glands were divided into two groups, one with ablation of conjunctival goblet cells by topical soaking of trichloroacetic acid (TCA) to the bulbar conjunctiva (n = 3) and one without (n = 4), and the conditions of DED were assessed weekly using Schirmer test, tear breakup time (TBUT), tear osmolarity, and National Eye Institute (NEI) fluorescein staining grading. After 8 weeks, the rabbits were sacrificed, and the eyes were enucleated for histopathological examination. Results Histopathological analysis revealed corneal epithelial thinning in both groups. While TCA soaking significantly decreased the density of conjunctival goblet cells, DED rabbits without TCA also showed a partial reduction in goblet cell density, potentially attributable to dacryoadenectomy. Both groups showed significant decreases in Schirmer test and TBUT, as well as an increase in tear osmolarity. In DED rabbits with TCA soaking, tear osmolarity increased markedly, suggesting that tear osmolarity is highly sensitive to loss and/or dysfunction of conjunctival goblet cells. Fluorescein staining was gradually and similarly increased in both groups, suggesting that fluorescein staining may not reveal an early disruption of the tear film until the prolonged progression of DED. Conclusion The Schirmer test, TBUT, tear osmolarity, and NEI fluorescein grading are distinct, yet complementary, clinical assessments for the evaluation of DED. By performing these assessments in definitive DED rabbit models, both with and without ablation of conjunctival goblet cells, the role of these cells in the homeostasis of tear osmolarity is highlighted. Characterizing the robustness of these assessments in identifying the underlying conditions of DED will guide a more appropriate management for patients with DED.

Combination therapy with medical gases (nitric oxide and molecular hydrogen): safety assessment

Inhaled nitric oxide (NO) and molecular hydrogen (iH2) are actively studied nowadays. The therapeutic algorithms for their use in the various conditions are being developed, but the combined use of these medical gases (MG) has not been studied well enough.The aim of the study was to assess the safety of iNO and iH2 combination in healthy volunteers.Methods. 10 healthy volunteers (4 males and 6 females), mean age 24.0 ± 1.3 years, were included in the open non-comparative prospective study. All volunteers received a single combined inhalation of NO and H2 for 90 minutes. The NO concentration was 60 ppm and the H2 concentration did not exceed 4% in the gas mixture. Changes in the vital signs, arterial blood gases, and hemodynamic parameters were evaluated. The hemodynamic parameters were investigated before and after inhalation using echocardiography (Vivid E9 General Electric, USA). We also assessed the microcirculation of the bulbar conjunctiva (“OKO” capillaroscope), the main functional lung parameters, and the diffusion lung capacity (GANSHORN PowerCube Body apparatus). The clinical side effects were recorded. After inhalation, the serum concentration of methemoglobin was evaluated.Results. When comparing the results before and after MG inhalation, there was no negative impact on the vital signs, arterial blood gases (РaO2, РaСO2, SаO2), the functional lung volumes (FEV1, FVC, FEV1 / FVC), the diffusion test parameters, main EchoCG hemodynamic data (ejection fraction, tricuspid annular plane systolic excursion (TAPSE), mean pulmonary artery pressure, left and right ventricular sizes) (p &gt; 0,05). After inhalation, the microcirculatory parameters (the volume velocity in arterioles and venules and the arteriolar diameter) increased significantly (p &lt; 0.05). We did not observe the increase in serum methemoglobin concentration (0.59 ± 0.11%). No clinical side effects were reported during the study.Conclusions. Combined use of inhaled NO / H2 is clinically safe, does not have any negative impact on hemodynamic parameters, functional lung volumes, and arterial blood gases. The improvement of the microcirculation was noted after a single inhalation. This new method can be recommended for further studies of the therapeutic effect in various conditions.

Clinical pathological and genetic mutation characteristics of conjunctival lymphoepithelial carcinoma

Objective: To analyze the clinical pathological and genetic mutation characteristics of conjunctival lymphoepithelial carcinoma. Methods: A retrospective case series study was conducted. Data from three patients diagnosed with conjunctival lymphoepithelial carcinoma and treated with tumor resection surgery at Tianjin Eye Hospital from January 2006 to December 2022 were collected. Four paraffin specimens (including one patient undergoing two surgeries) were subjected to immunohistochemical staining for epithelial antigen and lymphocytic antigen. Epstein-Barr virus (EBV)-encoded RNA (EBER) was detected using in situ hybridization, and whole-exome sequencing was performed on three specimens from two patients using next-generation sequencing methods. Results: All three patients were males aged over 65, with a disease duration ranging from 3 to 44 months. The tumors were unilateral, located on the bulbar or limbal conjunctiva, appearing red, with a maximum diameter of 4-20 mm. Imaging examinations revealed anterior location of the tumors with no involvement of the orbital bone, extraocular muscles, optic nerve, or paranasal sinuses. No local lymph node metastasis was observed in any patient. Pathological findings included undifferentiated carcinoma nests with significant reactive lymphocytic and plasma cell infiltration. Tumor cells were positive for pan-cytokeratin (CK-pan), epithelial membrane antigen (EMA), tumor protein 40 (p40), and tumor protein 63 (p63), with a cell proliferation index (Ki67) exceeding 80%. Cluster of differentiation 20 (CD20), CD3, and CD8 were positive for lymphocytes. In situ hybridization showed partial tumor cell expression of EBER in two specimens of one patient. Whole-exome sequencing revealed 58, 50, and 36 mutated genes in the three specimens, with enriched signaling pathways including melanoma signaling pathway, Notch1 signaling pathway, and RHOQ GTP cycle; enriched biochemical processes included amino acid starvation response, programmed cell death, regulation of lipid synthesis, sodium ion transport, and chromosome segregation. The common mutated gene in all three specimens was SZT2, and SZT2 was involved in the amino acid starvation response. One patient underwent a second complete resection surgery 40 months after partial excision, while the other two underwent complete resection surgery without recurrence. Two patients did not undergo radiation or chemotherapy, and one was lost to follow-up. Conclusions: Conjunctival lymphoepithelial carcinoma is associated with prominent lymphocytic and plasma cell infiltration, some cases are associated with EBV infection, and SZT2 mutations are present in conjunctival lymphoepithelial carcinoma.

Biometry-Based Technique for Determining the Anterior Scleral Thickness: Validation Using Optical Coherence Tomography Landmarks.

Considering the potential role of anterior scleral thickness (AST) in myopia and the ubiquitous use of optical biometers, we applied and validated a biometry-based technique for estimating AST using optical coherence tomography (OCT) landmarks. The AST was determined across four meridians in 62 participants (aged 20-37years) with a swept-source OCT and a noncontact optical biometer at a mean ± SD distance of 3.13 ± 0.88mm from the limbus. The biometer's graticule was focused and aligned with the anterior scleral reflex, which led to the generation of four prominent A-scan peaks: P1 (anterior bulbar conjunctiva), P2 (anterior episclera), P3 (anterior margin of anterior sclera), and P4 (posterior margin of anterior sclera), which were analyzed and compared with the corresponding OCT landmarks to determine tissue thickness. The AST measurements between biometer and OCT correlated for all meridians (r ≥ 0.70, overall r = 0.82; coefficient of variation [CV], 9%-12%; P < 0.01). The mean difference ± SD between two instruments for overall AST measures was 3 ± 2.8 µm (range, -18 to +16µm; lower limits of agreement, -89 to +83 µm; P = 0.23) across all meridians. The mean ± SE AST with both instruments was found to be thickest at the inferior (562 ± 7µm and 578 ± 7µm) and thinnest at the superior (451 ± 7µm and 433 ± 6µm) meridian. The biometer demonstrated good intrasession (CV, 8.4%-9.6%) and intersession (CV, 7.9%-13.3%) repeatability for AST measurements across all meridians. The noncontact optical biometer, which is typically used to determine axial length, is capable of accurately estimating AST based on OCT landmarks. The high-resolution optical biometers can demonstrate wider application in the field of myopia research and practice to determine AST.