The Conjunctival Microbiome and Dry Eye: What We Know and Controversies

ABSTRACT

Dry eye disease is a common multifactorial condition that may be idiopathic or associated with autoimmune conditions, such as Sjogren syndrome. Commensal microorganisms modify immune responses, so it is relevant to understand how they modify such immune-mediated diseases. Microbiota in the gut regulate inflammation in the eye, and conversely, severe inflammation of the ocular surface results in alteration of gut microbiome. The conjunctiva microbiome can be analyzed using 16S or shotgun metagenomics. The amount of microbial DNA in ocular surface mucosa relative to human DNA is limited compared with the case of the intestinal microbiome. There are challenges in defining, harvesting, processing, and analyzing the microbiome in the ocular surface mucosa. Recent studies have shown that the conjunctiva microbiome depends on age, presence of local and systemic inflammation, and environmental factors. Microbiome-based therapy, such as the use of oral probiotics to manage dry eye disease, has initial promising results. Further longitudinal studies are required to investigate the alteration of the conjunctival microbiome after local therapy and surgery.

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.

Neuropathic Corneal Pain: Tear Proteomic and Neuromediator Profiles, Imaging Features, and Clinical Manifestations

PURPOSE

To investigate the tear proteomic and neuromediator profiles, in vivo confocal microscopy (IVCM) imaging features, and clinical manifestations in neuropathic corneal pain (NCP) patients.

DESIGN

Cross-sectional study.

METHODS

A total of 20 NCP patients and 20 age-matched controls were recruited. All subjects were evaluated by corneal sensitivity, Schirmer test, tear break-up time, and corneal and ocular surface staining, Ocular Surface Disease Index and Ocular Pain Assessment Survey questionnaires were administered, as well as IVCM examinations for corneal nerves, microneruomas, and epithelial and dendritic cells. Tears were collected for neuromediator and proteomic analysis using enzyme-linked immunosorbent assay and data-independent acquisition mass spectrometry.

RESULTS

Burning and sensitivity to light were the 2 most common symptoms in NCP. A total of 188 significantly dysregulated proteins, such as elevated metallothionein-2, creatine kinases B-type, vesicle-associated membrane protein 2, neurofilament light polypeptide, and myelin basic protein, were identified in the NCP patients. The top 10 dysregulated biological pathways in NCP include neurotoxicity, axonal signaling, wound healing, neutrophil degradation, apoptosis, thrombin signaling mitochondrial dysfunction, and RHOGDI and P70S6K signaling pathways. Compared to controls, the NCP cohort presented with significantly decreased corneal sensitivity (P < .001), decreased corneal nerve fiber length (P = .003), corneal nerve fiber density (P = .006), and nerve fiber fractal dimension (P = .033), as well as increased corneal nerve fiber width (P = .002), increased length, total area and perimeter of microneuromas (P < .001, P < .001, P = .019), smaller corneal epithelial size (P = .017), and higher nerve growth factor level in tears (P = .006).

CONCLUSIONS

These clinical manifestations, imaging features, and molecular characterizations would contribute to the diagnostics and potential therapeutic targets for NCP.

[Influences and mechanism of extracellular vesicles from dermal papilla cells of mice on human hypertrophic scar fibroblasts]

Objective: To investigate the influences and mechanism of extracellular vesicles from dermal papilla cells (DPC-EVs) of mice on human hypertrophic scar fibroblasts (HSFs). Methods: The study was an experimental research. The primary dermal papilla cells (DPCs) of whiskers were extracted from 10 6-week-old male C57BL/6J mice and identified successfully. The DPC-EVs were extracted from the 3rd to 5th passage DPCs by ultracentrifugation, and the morphology was observed through transmission electron microscope and the particle diameter was detected by nanoparticle tracking analyzer (n=3) at 24 h after culture. The 3rd passage of HSFs were divided into DPC-EV group and phosphate buffer solution (PBS) group, which were cultured with DPC-EVs and PBS, respectively. The cell scratch test was performed and cell migration rate at 24 h after scratching was calculated (n=5). The cell proliferation levels at 0 (after 12 h of starvation treatment and before adding DPC-EVs or PBS), 24, 48, 72, and 96 h after culture were detected by using cell counting kit 8 (n=4). The protein expressions of α-smooth muscle actin (α-SMA) and collagen typeⅠ (ColⅠ) in cells at 24 h after culture were detected by immunofluorescence method and Western blotting, and the protein expression of Krüppel-like factor 4 (KLF4) in cells at 24 h after culture was detected by Western blotting. After the 3rd passage of HSFs were cultured with DPC-EVs for 24 h, the cells were divided into blank control group, KLF4 knockdown group, and KLF4 overexpression group according to the random number table. The cells in blank control group were only routinely cultured for 48 h. The cells in KLF4 knockdown group and KLF4 overexpression group were incubated with KLF4 knockdown virus for 24 h, then the cells in KLF4 knockdown group were routinely cultured for 24 h while the cells in KLF4 overexpression group were incubated with KLF4 overexpression virus for 24 h. The protein expressions of KLF4, α-SMA, and ColⅠ in cells were detected by Western blotting at 48 h after culture. Results: At 24 h after culture, the extracted DPC-EVs showed vesicular structure with an average particle diameter of 108.8 nm. At 24 h after scratching, the migration rate of HSFs in PBS group was (54±10)%, which was significantly higher than (29±8)% in DPC-EV group (t=4.37, P<0.05). At 48, 72, and 96 h after culture, the proliferation levels of HSFs in DPC-EV group were significantly lower than those in PBS group (with t values of 4.06, 5.76, and 6.41, respectively, P<0.05). At 24 h after culture, the protein expressions of α-SMA and ColⅠ of HSFs in DPC-EV group were significantly lower than those in PBS group, while the protein expression of KLF4 was significantly higher than that in PBS group. At 48 h after culture, compared with those in blank control group, the protein expression of KLF4 of HSFs in KLF4 knockdown group was down-regulated, while the protein expressions of α-SMA and ColⅠ were both up-regulated; compared with those in KLF4 knockdown group, the protein expression of KLF4 of HSFs in KLF4 overexpression group was up-regulated, while the protein expressions of ColⅠ and α-SMA were down-regulated. Conclusions: The DPC-EVs of mice can inhibit the proliferation and migration of human HSFs and significantly inhibit the expressions of fibrosis markers α-SMA and ColⅠ in human HSFs by activating KLF4.

[Perioperative management of wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy and its clinical effects]

Objective: To investigate the perioperative management of wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy, and to evaluate its clinical effects. Methods: This study was a retrospective observational study. From January 2017 to December 2022, 36 patients with wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy who were conformed to the inclusion criteria were admitted to the Burn Center of PLA of the First Affiliated Hospital of Air Force Medical University, including 23 males and 13 females, aged 25 to 81 years. Preparation for surgery was made. For patients with suspected retrosternal mediastinal abscess cavity, all cancellous bone of the unhealed sternum was bitten off to fully expose the retrosternal mediastinum, remove the source of infection and granulation tissue, and to fill the sternum defect with flipped unilateral pectoralis major muscle. For patients who had no retrosternal mediastinal infection but had fresh granulation tissue in unhealed sternal wounds, the necrotic tissue and a small amount of necrotic sternum were palliatively removed, and bilateral pectoralis major muscles were advanced and abutted to cover the sternal defect. After the skin in the donor area was closed by tension-relieving suture, continuous vacuum sealing drainage was performed, and continuous even infusion and lavage were added 24 hours later. The thorax was fixed with an armor-like chest strap, the patients were guided to breathe abdominally, with both upper limbs fixed to the lateral chest wall using a surgical restraint strap. The bacterial culture results of wound exudation specimens on admission were recorded. The wound condition observed during operation, debridement method, muscle flap covering method, intraoperative bleeding volume, days of postoperative infusion and lavage, lavage solution volume and changes on each day, and postoperative complications and wound healing time were recorded. After discharge, the wound healing quality, thorax shape, and mobility functions of thorax and both upper limbs were evaluated during follow-up. The stability and closure of sternum were observed by computed tomography (CT) reexamination. Results: On admission, among 36 patients, 33 cases were positive and 3 cases were negative in bacterial culture results of wound exudation specimens. Intraoperative observation showed that 26 patients had no retrosternal mediastinal infection but had fresh granulation tissue in unhealed sternal wounds, palliative debridement was performed and bilateral pectoralis major muscles were advanced and abutted to cover the defect. In 10 patients with suspected retrosternal mediastinal abscess cavity, the local sternum was completely removed by bite and the defect was covered using flipped unilateral pectoralis major muscle. During the operation, one patient experienced an innominate vein rupture and bleeding of approximately 3 000 mL during mediastinal exploration, and the remaining patients experienced bleeding of 100-1 000 mL. Postoperative infusion and lavage were performed for 4-7 days, with a lavage solution volume of 3 500-4 500 mL/d. The lavage solution gradually changed from dark red to light red and finally clear. Except for 1 patient who had suture rupture caused by lifting the patient under the armpit during nursing on the 3rd day after surgery, the wounds of the other patients healed smoothly after surgery, and the wound healing time of all patients was 7-21 days. Follow-up for 3 to 9 months after discharge showed that the patient who had suture rupture caused by armpit lifting died due to multiple organ failure. In 1 patient, the armor-like chest strap was removed 2 weeks after surgery, and the shoulder joint movement was not restricted, resulting in local rupture of the suture, which healed after dressing change. The wounds of the remaining patients healed well, and they resumed their daily life. The local skin of patient's pectoralis major muscle defect was slightly sunken and lower than that of the contralateral thorax in the patients undergoing treatment of pectoralis major muscle inversion, while no obvious thoracic deformity was observed in patients undergoing treatment with pectoralis major muscle propulsion and abutment. The chest and upper limb movement in all patients were slightly limited or normal. CT reexamination results of 10 patients showed that the sternum was stable, the local sternum was closed or covered completely with no lacuna or defects. Conclusions: Once the wound associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy is formed, individualized and precise debridement should be performed as soon as possible, different transfer ways of pectoralis major muscle flap should be chosen to cover the defect, and postoperative continuous infusion and lavage together with strict thorax and shoulder joint restraint and immobilization should be performed. This treatment strategy can ensure good wound healing without affecting the shape and function of the donor area.

Neuropathic Corneal Pain after Coronavirus Disease 2019 (COVID-19) Infection

INTRODUCTION

This is a case report of a patient with neuropathic corneal pain after coronavirus disease 2019 (COVID-19) infection.

METHODS

A previously healthy 27-year-old female presented with bilateral eye pain accompanied by increased light sensitivity 5 months after COVID-19 infection. She was diagnosed with neuropathic corneal pain based on clear corneas without fluorescein staining, alongside the presence of microneuromas, dendritic cells, and activated stromal keratocytes identified bilaterally on in vivo confocal microscopy.

RESULTS

The patient's tear nerve growth factor, substance P, and calcitonin gene-related peptide levels were 5.9 pg/mL, 2978.7 pg/mL, and 1.1 ng/mL, respectively, for the right eye and 23.1 pg/mL, 4798.7 pg/mL, and 1.2 ng/mL, respectively, for the left eye, suggesting corneal neuroinflammatory status. After 6 weeks of topical 0.1% flurometholone treatment, decreased microneuroma size, less extensive dendritic cells, and reduced tear nerve growth factor and substance P levels were observed. The scores on the Ocular Pain Assessment Survey showed an improvement in burning sensation and light sensitivity, decreasing from 80% and 70% to 50% for both.

CONCLUSIONS

Neuropathic corneal pain is a potential post-COVID-19 complication that warrants ophthalmologists' and neurologists' attention.

Two-Photon and Multiphoton Microscopy in Anterior Segment Diseases of the Eye

Two-photon excitation microscopy (TPM) and multiphoton fluorescence microscopy (MPM) are advanced forms of intravital high-resolution functional microscopy techniques that allow for the imaging of dynamic molecular processes and resolve features of the biological tissues of interest. Due to the cornea's optical properties and the uniquely accessible position of the globe, it is possible to image cells and tissues longitudinally to investigate ocular surface physiology and disease. MPM can also be used for the in vitro investigation of biological processes and drug kinetics in ocular tissues. In corneal immunology, performed via the use of TPM, cells thought to be intraepithelial dendritic cells are found to resemble tissue-resident memory T cells, and reporter mice with labeled plasmacytoid dendritic cells are imaged to understand the protective antiviral defenses of the eye. In mice with limbal progenitor cells labeled by reporters, the kinetics and localization of corneal epithelial replenishment are evaluated to advance stem cell biology. In studies of the conjunctiva and sclera, the use of such imaging together with second harmonic generation allows for the delineation of matrix wound healing, especially following glaucoma surgery. In conclusion, these imaging models play a pivotal role in the progress of ocular surface science and translational research.

A Systematic Review of Tear Vascular Endothelial Growth Factor and External Eye Diseases

We aim to summarize the current evidence of Vascular endothelial growth factors (VEGF)s in external eye diseases and determine whether serum and plasma VEGF levels are associated with tear and ocular surface tissues. A systematic search of PUBMED and EMBASE was conducted using PRISMA guidelines between October 2022 and November 2023, with no restriction on language or publication date. Search terms included relevant MESH terms. These studies were evaluated for quality, and an assessment of the risk of bias was also carried out. Extracted data were then visually represented through relevant tables or figures. The initial literature search yielded 777 studies from PUBMED, 944 studies from EMBASE, and 10 studies from manual searches. Fourteen eligible studies were identified from 289 articles published from 2000 to 2023 in the English language or with English translations, including rabbit models, murine models, and human-derived samples. Most studies were retrospective in nature and case-control studies. Various common external eye diseases, such as dry eye disease (DED) and allergic eye disease were investigated. Despite limitations and small sample sizes, researchers have found elevated tissue levels of the VEGF in the vascularized cornea, especially in animal models, but there is no evidence of clear changes in the tear concentrations of VEGF in DED and allergic eye disease. Tear VEGF is associated with corneal vascularization. Anti-VEGF therapies may have the potential to manage such conditions.

Salivary Gland Transplantation as a Promising Approach for Tear Film Restoration in Severe Dry Eye Disease

With increased awareness of dry eye disease (DED), a multitude of therapeutic options have become available. Nevertheless, the treatment of severe DED remains difficult. In a patient whose DED is related to the loss of lacrimal function without severe destruction of the salivary glands, autologous transplantation of the latter as functioning exocrine tissue to rebuild a stable tear film is an attractive idea. All three major and minor salivary glands have been used for such transplantation. Due to the complications associated with and unfavorable prognosis of parotid duct and sublingual gland transplantation, surgeons now prefer to use the submandibular gland (SMG) for such procedures. The transplantation of the SMG not only has a high survival rate, but also improves dry eye symptoms and signs for more than 20 years post-surgery. The regulation of the secretion of the transplanted SMG is critical because the denervated SMG changes its mechanism of secretion. Innovative procedures have been developed to stimulate secretion in order to prevent the obstruction of the Wharton's duct and to decrease secretion when postoperative "epiphora" occurs. Among the minor salivary glands, the transplantation of the labial salivary glands is the most successful in the long-term. The measurement of the flow rates of minor salivary glands and donor-site selection are critical steps before surgery.

Clinical associations of corneal neuromas with ocular surface diseases

Corneal neuromas, also termed microneuromas, refer to microscopic, irregularly-shaped enlargements of terminal subbasal nerve endings at sites of nerve damage or injury. The formation of corneal neuromas results from damage to corneal nerves, such as following corneal pathology or corneal or intraocular surgeries. Initially, denervated areas of sensory nerve fibers become invaded by sprouts of intact sensory nerve fibers, and later injured axons regenerate and new sprouts called neuromas develop. In recent years, analysis of corneal nerve abnormalities including corneal neuromas which can be identified using in vivo confocal microscopy, a non-invasive imaging technique with microscopic resolution, has been used to evaluate corneal neuropathy and ocular surface dysfunction. Corneal neuromas have been shown to be associated with clinical symptoms of discomfort and dryness of eyes, and are a promising surrogate biomarker for ocular surface diseases, such as neuropathic corneal pain, dry eye disease, diabetic corneal neuropathy, neurotrophic keratopathy, Sjögren's syndrome, bullous keratopathy, post-refractive surgery, and others. In this review, we have summarized the current literature on the association between these ocular surface diseases and the presentation of corneal microneuromas, as well as elaborated on their pathogenesis, visualization via in vivo confocal microscopy, and utility in monitoring treatment efficacy. As current quantitative analysis on neuromas mainly relies on manual annotation and quantification, which is user-dependent and labor-intensive, future direction includes the development of artificial intelligence software to identify and quantify these potential imaging biomarkers in a more automated and sensitive manner, allowing it to be applied in clinical settings more efficiently. Combining imaging and molecular biomarkers may also help elucidate the associations between corneal neuromas and ocular surface diseases.

New developments in the management of persistent corneal epithelial defects

A persistent epithelial defect (PED) is a corneal epithelial defect that failed to heal after 2weeks. It is a condition that carries much morbidity, and our understanding of PED remains poor, with current treatment methods often having unsatisfactory outcomes. With PEDs becoming more prevalent, more efforts are required to establish reliable treatment modalities. Our reviews describe the causes of PEDs and the different approaches developed to manage them, as well as their associated limitations. Emphasis is placed on understanding various advances in the development of new treatment modalities. We have also described a case of a woman with a background of graft-versus-host disease on long-term topical corticosteroids who developed complicated PED involving both eyes. The current approach to managing PEDs generally involves exclusion of an active infection, followed by treatment modalities that aim to encourage corneal epithelial healing. Success rates, however, remain far from desirable, as treatment remains challenging due to multiple underlying etiologies. In summary, advances in the development of new therapies may be able to facilitate progress in the understanding and treatment of PED.

Relationship between dry eye symptoms and quality of life: associations and mediation analysis

PURPOSE

(1) To determine the independent association of dry eye symptoms with health-related quality of life (HRQoL) in the Singapore population and (2) to further investigate which factors mediate this association.

METHODS

In this cross-sectional study, 7707 participants were included. The presence of dry eye symptoms was defined as experiencing at least one out of the six symptoms either 'often' or 'all the time'. The EuroQoL-5 dimensions (EQ-5D) utility instrument (raw scores converted to UK time trade-off (TTO) values) was used to assess generic HRQoL and the overall score from the Visual Functioning Questionnaire for visual functioning. The association between dry eye symptoms and EQ-5D was investigated using multivariable linear regression, adjusting for demographic and socioeconomic information, comorbidities, systemic and ocular examinations results. Mediation analysis was used to determine whether certain factors mediated this association.

RESULTS

After adjusting for relevant factors, those with dry eye symptoms had significantly lower HRQoL (difference in EQ-5D TTO: -0.062 (95% CI -0.073 to -0.050)), with the inability to open eyes affected the most (-0.101 (95% CI -0.161 to -0.042)), followed by a sandy sensation (-0.089 (95% CI -0.121 to -0.058)), a burning sensation (-0.070 (95% CI -0.105 to -0.036)), red eyes (-0.059 (95% CI -0.082 to -0.036)), a dry sensation (-0.058 (95% CI -0.072 to -0.044)) and crusting of eyelids (-0.040 (95% CI -0.071 to -0.008)). Visual functioning and the presence of recent falls accounted for 8.63% (4.98%-14.5%) and 2.93% (0.04%-5.68%) of the indirect relationship between dry eye and HRQoL, respectively.

CONCLUSION

Dry eye symptoms were independently associated with poor HRQoL. Moreover, this was partly mediated by reduced visual functioning and experiencing recent falls. Our results suggest that efforts to reduce severity of dry eye symptoms are essential to optimise patients' overall functioning and well-being.

Allogeneic Umbilical Cord Plasma Eyedrops for the Treatment of Recalcitrant Dry Eye Disease Patients

BACKGROUND

Dry eye disease is a significant disease in Singapore. While there have been studies using allogenic cord serum for the treatment of dry eye disease, treatment of dry eyes with allogenic umbilical cord plasma drops has yet to be started in Singapore.

PURPOSE

To evaluate the effectiveness of umbilical cord plasma eyedrops for the treatment of recalcitrant dry eyes in a local Singaporean context.

METHODS

This is an observational, longitudinal, interventional study for dry eye patients who did not show clear improvement after standard therapy. Patients were recruited from 2020 to 2023 from the dry eye clinic of the Singapore National Eye Center. Umbilical cord plasma was delivered frozen to patients and stored in home freezers. All participants underwent a standardized clinical evaluation for dry eye, and data were collected.

RESULTS

There were 40 participants (7 males and 33 females). The duration of follow-up was 5.52 ± 1.57 months. Kerato-epitheliopathy staining score, TBUT (tear breakup time), and SPEED (Standard Patient Evaluation of Eye Dryness Questionnaire) scores significantly improved after treatment. No statistically significant improvement was found in terms of visual acuity, according to Schirmer's score.

CONCLUSION

Cord plasma eye drops significantly improved kerato-epitheliopathy staining scores in recalcitrant dry eye patients. Allogeneic plasma is a promising form of treatment for recalcitrant dry eye.

Dawn of Staging for Head and Neck Soft Tissue Sarcoma: Validation of the Novel 8th Edition AJCC T Classification and Proposed Stage Groupings

PURPOSE/OBJECTIVE(S)

After decades of stagnation, the 8th edition TNM (TNM8) introduced a new T classification for head and neck (HN) soft tissue sarcomas (STS). New size cutoffs of 2 and 4 cm define T1-3, and a novel T4 category is defined by local invasion of adjoining structures. These size cutoffs had been chosen arbitrarily to advance data collection in this unique disease site since literature showed approximately 70% of HN STS did not reach the previous size threshold (5 cm) for the existing T1 category. The definition of the TNM8 T categories also align with mucosal HN cancers. No stage grouping for HN STS was defined since this new classification required more data collection to derive stage groups. This study aims to validate the TNM8 T classification and to propose stage groupings.

MATERIALS/METHODS

Clinical data of all adult (>16 years) HN STS patients treated from 1988 - 2019 with curative intent in our tertiary cancer center were retrieved from a prospective database, and supplemented with chart review. As per TNM8, cutaneous angiosarcoma, embryonal and alveolar rhabdomyosarcoma, Kaposi sarcoma, and dermatofibrosarcoma protuberans were excluded due to their different behavior. Multivariate analysis (MVA) identified prognostic factors for overall survival (OS). Adjusted hazard ratios (AHR) and recursive partitioning analysis (RPA) were used to derive stage groupings. Stage grouping performance for OS was assessed and also compared against the existing TNM8 groups for non-HN STS.

RESULTS

A total of 221 patients (N1: 2; M1: 2) were included. Of the 219 M0 patients, 63% were males; median tumor size was 3.0 cm (range: 0.3-14.0); the proportion of TNM8 T1-T4 were 35%, 34%, 26%, and 5%, respectively. Median follow up was 5.9 years. Five-year OS was 79%. MVA confirmed the prognostic value of T category (T4 HR 7.73, 95% CI 3.62-16.5) and grade (G2/3 vs G1 HR 3.7, 95% CI 1.82-7.53), in addition to age (HR 1.03, 95% CI 1.01-1.04) (all p<0.001) for OS. AHR model derived T1-3_Grade 1 as stage 1; T1-3_Grade 2/3 as stage II; and T4_any Grade or any T_N1 as stage III (Table 1); the corresponding 5-year OS was 93%, 73%, and 38%, respectively. Both patients with M1 died within 1.5 years after diagnosis and M1 disease was designated stage IV. The AHR-grouping outperformed the RPA and non-HN TNM8 stage grouping for hazard consistency, hazard discrimination, percent variance explained, hazard difference, and sample size balance.

CONCLUSION

The novel T4 category introduced in TNM8 is associated with a >7 fold increased risk of death. Grade continues to be a critical prognostic factor in HN STS. The TNM8 HN STS T classifications have been validated, and the proposed new stage groupings with TNM8 incorporating grade have excellent performance for OS.

Outcomes after Contemporary Definitive Radiotherapy Alone in Patients with TNM-7 Stage III/IV Head and Neck Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

This study was undertaken to determine outcomes and prognostic factors of definitive intensity-modulated radiotherapy (IMRT) alone for patients with TNM-7 stage III/IV HNSCC who did not receive concurrent chemotherapy.

MATERIALS/METHODS

We evaluated TNM-7 stage III/IV HNSCC patients treated with definitive IMRT alone in our institution from 2004-2019. Patients were reclassified according to TNM-8 staging. Stage II HPV+ oropharyngeal cancers (OPC) were subdivided into T1-2N2 and T3N0-2 for analysis. The rationale for chemotherapy omission was obtained retrospectively from clinical documentation. Recurrence-free survival (RFS) and overall survival (OS) were estimated stratified by HPV status (determined by p16 staining, sometimes supplemented by HPV DNA testing). Multivariable analysis (MVA) identified prognostic factors for RFS and OS, taking into account stage and IMRT regimen. Age, performance status, and smoking were also examined for OS.

RESULTS

A total of 1083 patients were included (460 HPV+ and 623 HPV-). Reasons for omission of chemotherapy were: age >70 years or frailty (n = 551, 51%), cisplatin contraindication (n = 241, 22%), patient refusal (n = 106, 10%), and clinician's decision (n = 185, 17%). Median age was 67 years for HPV+ and 70 years for HPV- cohorts. IMRT mostly utilized altered fractionation regimens (n = 1016, 94%): moderately accelerated (Acc) (70 Gy/35 fractions [f]/6 weeks [w], 55%), hypofractionated (Hypo) (60 Gy/25f/5w, 14%), and hyperfractionated-accelerated (Hyper) (64 Gy/40f/4w, 25%). Median follow-up was 5 years. Five-year RFS and OS for HPV+ TNM-8 stage I/T1-2N2/T3N0-N2/III were 89%/86%/76%/52% and 83%/80%/64%/33% respectively (p<0.01). The same outcomes for HPV- TNM-8 stage III/IVA/IVB were 58%/52%/39% and 47%/27%/13%, respectively (p<0.01). MVA confirmed that HPV+ T3N0-2 subset within stage II and stage III (vs stage I) had lower RFS, and HPV- stage IVA and IVB (vs stage III) carried worse RFS and OS (Table).

CONCLUSION

Despite the retrospective nature and inherent selection bias, this large single institutional study shows that altered fractionated IMRT alone is an acceptable alternative for elderly, frail or cisplatin ineligible patients with HPV+ stage I/IIA (T1-2N2) OPC. Patients with HPV+ T3N0-2/stage III OPC and HPV- stage III/IV HNSCC have poor outcomes with IMRT alone and may benefit from alternative strategies.

The Prognostic and Predictive Value of Pre-Treatment Total Lymphocyte Count in HPV+ Oropharyngeal Carcinoma Receiving Definitive (Chemo-) Radiation

PURPOSE/OBJECTIVE(S)

Evidence of prognostic importance of pre-radiotherapy (RT) total lymphocyte counts (TLC) and interaction with addition of cisplatin (CRT) in HPV-positive oropharyngeal carcinoma (HPV+OPC) is conflicting. Recent data suggest patients with high TLC may not benefit from the addition of chemotherapy (Price et al, JCO 2022). We assess the prognostic and predictive value of TLC in a large single center HPV+OCP cohort.

MATERIALS/METHODS

All HPV+OPC patients treated at a single academic center with definitive RT/CRT between 2005-2018 were included. Pre-treatment TLC up to 6 weeks prior to RT start were considered. Multivariable analysis (MVA) was applied to assess the prognostic importance of TLC (continuous variable), adjusted for age, gender, performance status, TNM-8 stage, and smoking status in the CRT and RT subgroups. The actuarial rates of locoregional control (LRC), distant control (DC), and overall survival (OS) were calculated using Kaplan-Meier and competing risk methods, stratified by low vs high TLC (determined using Contal and O'Quigley method for optimal cutoff).

RESULTS

Among 1153 eligible patients, 707 (61%) were treated with CRT. Median age was 59.7 (range 22.7-92.2) years. 526 patients were (46%) TNM-8 stage I, 366 (32%) stage II and 261 (23%) stage III. Median TLC was 1.6 x 109/L (range 0.1-8.5). Median follow-up was 5.5 years. On MVA, TLC was prognostic for patients receiving CRT (OS [adjusted hazard ration (aHR) 0.55 (0.38-0.79), p = 0.002], DC [aHR 0.57 (0.37-0.88), p = 0.011], LRC [aHR 0.57 (0.36-0.89), p = 0.014]) but not RT (OS [aHR 1.04 (0.82-1.31), p = 0.74], LRC [aHR 1.26 (0.86-1.85), p = 0.23], DC [aHR 0.87 (0.64-1.19), p = 0.4)]. The optimal TLC cut-off for OS with CRT was 1.9 x 109/L. Low vs high TLC patients receiving CRT had significantly inferior 5-year DC (87% vs 93%, p = 0.017) and OS (84% vs 90%, p = 0.026). The benefit of higher TLC was most evident in stage II disease (table 1). CRT vs RT improved OS for stage II/III disease at high and low TLC.

CONCLUSION

Pre-treatment TLC is prognostic in a large cohort of HPV+OPC patients receiving CRT but not RT alone. Further investigation of the interaction of cisplatin and immune response during RT is warranted. The omission of chemotherapy based on TLC is not supported.

Quantum molecular resonance electrotherapy (Rexon-Eye) for recalcitrant dry eye in an Asian population

Objectives

To assess the safety, efficacy, patients' satisfaction and acceptability of Rexon-Eye electrotherapy in treating Asian severe dry eye disease (DED) patients.

Methods

Prospective parallel-arm pilot study recruiting 40 DED Chinese patients with >moderate recalcitrant DED (Contact Lens Research Unit [CCLRU] > grade 2). Subjects were randomized into 2 groups, undergoing four weekly treatment sessions each: group 1 received full treatment power; group 2 received control treatment (power 1 treatment). Non-invasive tear break-up time (NIBUT), cornea fluorescein staining graded via CCLRU and Schirmer's I test were compared pre- and 2 months post-treatment. The SPEED and QUEST questionnaires that evaluated subjective symptoms and treatment satisfaction, respectively, at baseline and 2 weeks post-treatment were carried out. Tear cytokine levels in both groups were examined at 2 weeks post-treatment.

Results

The amount of improvement in post-treatment corneal staining in the inferior corneal zone was significant in Group 1 (p = 0.038) but not in Group 2 (p = 0.832). Group 1 eyes with worse baseline staining (total score >9.8) had a significantly greater reduction of corneal staining than those with better baseline staining (-11.7 ± 1.98 vs. -4.6 ± 2.89, p < 0.001). There were no other significant differences in NIBUT, Schirmer's 1 and cornea fluorescein staining grading within or between the groups.: Group 1 (n = 24) had improved subjective dryness scores compared to Group 2 (n = 16) (SPEED score: 6.38 + 4.16 vs. 10.0 + 6.36, p = 0.04). No significant differences were seen in 11 tear cytokine levels at 2 weeks post-treatment between the 2 groups.

Conclusion

In Asian DED patients treated with Rexon-Eye, inferior cornea staining showed significant improvement compared to placebo, and eyes with greater cornea staining at baseline achieved a greater improvement in staining. There were no other significant improvements in NIBUT and Schirmer's 1. Rexon-Eye also improved subjective DED scores in 41.7% of eyes without any adverse effects.

Impact of Exposomes on Ocular Surface Diseases

Ocular surface diseases (OSDs) are significant causes of ocular morbidity, and are often associated with chronic inflammation, redness, irritation, discomfort, and pain. In severe OSDs, loss of vision can result from ocular surface failure, characterised by limbal stem cell deficiencies, corneal vascularisation, corneal opacification, and surface keratinisation. External and internal exposomes are measures of environmental factors that individuals are exposed to, and have been increasingly studied for their impact on ocular surface diseases. External exposomes consist of external environmental factors such as dust, pollution, and stress; internal exposomes consist of the surface microbiome, gut microflora, and oxidative stress. Concerning internal exposomes, alterations in the commensal ocular surface microbiome of patients with OSDs are increasingly reported due to advancements in metagenomics using next-generation sequencing. Changes in the microbiome may be a consequence of the underlying disease processes or may have a role in the pathogenesis of OSDs. Understanding the changes in the ocular surface microbiome and the impact of various other exposomes may also help to establish the causative factors underlying ocular surface inflammation and scarring, the hallmarks of OSDs. This review provides a summary of the current evidence on exposomes in various OSDs.

Conjunctival infiltrates and cytokines in an experimental immune-mediated blepharoconjunctivitis rat model

Purpose

To characterize the histopathological and immunological findings of a rat model of allergic blepharoconjunctivitis (BC) and demonstrate its potential utility for the assessment of BC therapies.

Methods

Sprague-Dawley (SD) rats were immunized with ovalbumin (OVA) and topically challenged with OVA (BC group) or PBS (control group), while a corticosteroid group was pre-treated with triamcinolone acetate 24 h before the challenge. Morphological features were evaluated and tissues were harvested for histological, flow cytometry and cytokine analysis.

Results

The BC group rats developed eyelid excoriations, redness, and conjunctival edema 24 h after the OVA challenge, while corticosteroid pre-treated and PBS-challenged rats were unaffected. The BC features were reduced despite repeated challenges for 5 days. Massive immune cell infiltration was observed in conjunctivae of BC rats, while no significant infiltration was seen in the other groups. Populations of T cells, mono-macrophages, neutrophils, and NK cells made up more than 77% of CD45⁺7AAD^- cells in the conjunctival tissues. T cell proportions were increased at 96 h compared to 24 h post-challenge, while macrophages decreased during the same time period. Eosinophils and intraepithelial neutrophils were detected in the BC rats, but not in the PBS and corticosteroid groups. BC eyes had significantly higher levels of IFN-γ and IL-2, while IL-4 and IL-6 levels were similar to controls.

Conclusion

A robust BC response was detected in this rat model which was suppressed by corticosteroid pre-treatment. Immune cell composition and cytokine profiles changed over time.

Molecular Basis of Transglutaminase-2 and Muscarinic Cholinergic Receptors in Experimental Myopia: A Target for Myopia Treatment

Myopia, a prevalent refractive error disorder worldwide, is characterized by the elongation of the eye, leading to visual abnormalities. Understanding the genetic factors involved in myopia is crucial for developing therapeutic and preventive measures. Unfortunately, only a limited number of genes with well-defined functionality have been associated with myopia. In this study, we found that the homozygous TGM2-deleted gene in mice protected against the development of myopia by slowing down the elongation of the eye. The effectiveness of gene knockdown was confirmed by achieving a 60 percent reduction in TGM-2 transcript levels through the use of TGM-2-specific small interfering RNA (siRNA) in human scleral fibroblasts (SFs). Furthermore, treating normal mouse SFs with various transglutaminase inhibitors led to the down-regulation of TGM-2 expression, with the most significant reduction observed with specific TGM-2 inhibitors. Additionally, the study found that the pharmacological blockade of muscarinic receptors also slowed the progression of myopia in mice, and this effect was accompanied by a decrease in TGM-2 enzyme expression. Specifically, mice with homozygous mAChR5, mAChR1, and/or mAChR4 and knockout mice exhibited higher levels of TGM-2 mRNA compared to mice with homozygous mAChR2 and three knockout mice (fold changes of 5.8, 2.9, 2.4, -2.2, and -4.7, respectively; p < 0.05). These findings strongly suggest that both TGM-2 and muscarinic receptors play central roles in the development of myopia, and blocking these factors could potentially be useful in interfering with the progression of this condition. In conclusion, targeting TGM-2 may have a beneficial effect regarding myopia, and this may also be at least partially be the mechanism of anti-muscarinic drugs in myopia. Further studies should investigate the interaction between TGM-2 and muscarinic receptors, as well as the changes in other extracellular matrix genes associated with growth during the development of myopia.

[Activation of GABAergic neurons in the zona incerta accelerates anesthesia induction with sevoflurane and propofol without affecting anesthesia maintenance or awakening in mice]

OBJECTIVE

To explore the regulatory effects of GABAergic neurons in the zona incerta (ZI) on sevoflurane and propofol anesthesia.

METHODS

Forty-eight male C57BL/6J mice divided into 8 groups (n=6) were used in this study. In the study of sevoflurane anesthesia, chemogenetic experiment was performed in 2 groups of mice with injection of either adeno-associated virus carrying hM3Dq (hM3Dq group) or a virus carrying only mCherry (mCherry group). The optogenetic experiment was performed in another two groups of mice injected with an adeno-associated virus carrying ChR2 (ChR2 group) or GFP only (GFP group). The same experiments were also performed in mice for studying propofol anesthesia. Chemogenetics or optogenetics were used to induce the activation of GABAergic neurons in the ZI, and their regulatory effects on anesthesia induction and arousal with sevoflurane and propofol were observed; EEG monitoring was used to observe the changes in sevoflurane anesthesia maintenance after activation of the GABAergic neurons.

RESULTS

In sevoflurane anesthesia, the induction time of anesthesia was significantly shorter in hM3Dq group than in mCherry group (P < 0.05), and also shorter in ChR2 group than in GFP group (P < 0.01), but no significant difference was found in the awakening time between the two groups in either chemogenetic or optogenetic tests. Similar results were observed in chemogenetic and optogenetic experiments with propofol (P < 0.05 or 0.01). Photogenetic activation of the GABAergic neurons in the ZI did not cause significant changes in EEG spectrum during sevoflurane anesthesia maintenance.

CONCLUSION

Activation of the GABAergic neurons in the ZI promotes anesthesia induction of sevoflurane and propofol but does not affect anesthesia maintenance or awakening.

Epigenetic Activation of Circadian Clock Genes Elicits Inflammation in Experimental Murine Dry Eye

PURPOSE

To explore whether circadian clock genes contribute to elicit inflammation in experimental dry eye (EDE).

METHODS

RNA sequencing analyzed mRNA expression patterns in EDE model. RT-qPCR and/or Western blot determined the expression of inflammatory factors and circadian genes during EDE. MethylTarget™ assays determined the promoter methylation levels of Per genes in vivo. Per2 or Per3 knockdown assessed their effects on inflammatory factors in vitro.

RESULTS

We utilized an intelligently controlled environmental system (ICES) to establish a mouse EDE model. The significant upregulated genes were enriched for circadian rhythms. Therein lied oscillatory and time-dependent upregulation of PER2 and PER3, as well as their promoter hypomethylation during EDE. Silencing PER2 or PER3 significantly decreased inflammatory factor expression and also reversed such increased inflammatory response in azacitidine (AZA) treatment in vitro model.

CONCLUSIONS

Our findings suggest that DNA methylation mediated the upregulation of PER2 and PER3, leading to inflammatory response in EDE.

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

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

TFOS Lifestyle: Impact of lifestyle challenges on the ocular surface

Many factors in the domains of mental, physical, and social health have been associated with various ocular surface diseases, with most of the focus centered on aspects of dry eye disease (DED). Regarding mental health factors, several cross-sectional studies have noted associations between depression and anxiety, and medications used to treat these disorders, and DED symptoms. Sleep disorders (both involving quality and quantity of sleep) have also been associated with DED symptoms. Under the domain of physical health, several factors have been linked to meibomian gland abnormalities, including obesity and face mask wear. Cross-sectional studies have also linked chronic pain conditions, specifically migraine, chronic pain syndrome and fibromyalgia, to DED, principally focusing on DED symptoms. A systematic review and meta-analysis reviewed available data and concluded that various chronic pain conditions increased the risk of DED (variably defined), with odds ratios ranging from 1.60 to 2.16. However, heterogeneity was noted, highlighting the need for additional studies examining the impact of chronic pain on DED signs and subtype (evaporative versus aqueous deficient). With respect to societal factors, tobacco use has been most closely linked to tear instability, cocaine to decreased corneal sensitivity, and alcohol to tear film disturbances and DED symptoms.

Transglutaminase-2 is critical for corneal epithelial barrier function via positive regulation of Claudin-1

PURPOSE

Transglutaminase (TG)-2 is a ubiquitous multi-functional protein expressed in all living cells. The purpose of the current study was to investigate the role of TG-2 in corneal barrier function and its potential regulation of epithelial junctional proteins and transcription factors.

METHODS

Corneal barrier function to ions in TG-2-/- and TG-2+/+ mice was assessed by Ussing chamber assay. Hypo-osmolar water or FITC-dextran was applied on top of mouse eyes to evaluate the corneal barrier function to water and macromolecules. Western blots, qPCR and immunofluorescent staining were used to investigate the expression of tight junction proteins in TG-2-/- and TG-2+/+ mouse corneas, and also in TG-2 knockdown human corneal epithelial cells.

RESULTS

Corneal explants from TG-2-/- mice had a lower trans-epithelial electrical resistance compared to TG-2+/+ mice. When challenged by hypo-osmolar water, the central corneal thickness of TG-2-/- mice increased faster, and these mice had a faster rise of fluorescence in the anterior chamber after ocular exposure to FITC-dextran, compared to TG-2+/+. Claudin-1 protein and transcript levels were reduced in the cornea of TG-2-/- mice and in TG-2 knockdown human corneal epithelial cells. Slug which previously reported suppressing Claudin-1 transcription, was increased at both protein and transcript level in TG-2 knockdown cells. TG-2 and Claudin-1 protein levels were unchanged in shRNA and shTG cells after MG132 treatment, while Slug accumulated in treated cells.

CONCLUSION

TG-2 may positively regulate Claudin-1 through repressing Slug at transcript level, and thus it is critical for normal corneal barrier function.

[Clinical effects of autologous split-thickness skin grafting for prefabricating urethra combined with scrotal flap in repairing middle urethral defect with penile defect]

Objective: To investigate the clinical effects of autologous split-thickness skin grafting for prefabricating urethra combined with scrotal flap in repairing middle urethral defect with penile defect. Methods: The retrospective observational study was conducted. Eight male patients (aged 14 to 58 years) with middle urethral defect and penile defect caused by various injuries who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University from January 2015 to January 2022. The length of urethral defect was 3 to 5 cm, and the wound area of penile defect after debridement was 5.0 cm×2.5 cm to 7.0 cm×5.5 cm. All the patients underwent autologous split-thickness skin grafting for prefabricating defect urethra in stage Ⅰ, and urethral anastomosis was performed and unilateral scrotal flap was transferred to reconstruct urethra and penis in stage Ⅱ. The area of scrotal flap was 6.0 cm×3.0 cm to 8.0 cm×6.0 cm. The wound in the donor area of skin graft was covered by oil gauze, and the wound of flap donor area was sutured directly. On the 7th day after the operation of stage Ⅱ, the survival of the flap was observed. In 3 weeks after the operation of stage Ⅱ, the urinary flow rate was measured by the urinary flow rate detector (urinary flow rate >15 mL/s was regarded as unobstructed urination), the urinary fistula and erectile function were observed, and the self-made therapeutic satisfaction questionnaire was used to investigate the therapeutic satisfaction degree of patients. During follow-up, the appearance of the flap recipient area was observed, the Vancouver scar scale (VSS) was used to evaluate the scar situation in the donor areas of skin graft and flap, the urinary flow rate was detected as before, the urethral stricture, urinary fistula, and erectile function were observed, and the therapeutic satisfaction degree of patients was investigated. Results: On the 7th day after the operation of stage Ⅱ, the flaps survived completely in 8 patients. In 3 weeks after the operation of stage Ⅱ, the urinary flow rate was 25.3 (18.0, 38.5) mL/s, with unobstructed urination, without urinary fistula and with erectile function, and the score of therapeutic satisfaction degree was 14.3 (14.0, 15.0). During follow-up of 1 to 7 years, the flap recipient area of 8 patients was full in appearance and not swollen, with similar color to the surrounding tissue; the VSS scores of the donor areas of skin graft and flap were 11.5 (10.0, 13.0) and 10.5 (9.3, 12.0), respectively, the urinary flow rate was 24.6 (17.7, 34.1) mL/s, with no urethral stricture, urinary fistula, and erectile dysfunction, and the score of therapeutic satisfaction degree was 13.5 (13.3, 14.8). Conclusions: Autologous split-thickness skin grafting for prefabricating urethra combined with scrotal flap in repairing the urethral and penile defects not only reconstructs the structure of urethra and the shape of penis, but also restores the sensation and erectile function of penis, with few postoperative complications, no obvious scar hyperplasia, and high satisfaction degree of patients, which is worthy of clinical promotion.

Conjunctival T Cell Profile in Allogeneic Hematopoietic Stem Cell Transplant Patients after Instilling Topical Cyclosporine-A 0.1% Cationic Emulsion

INTRODUCTION

To profile conjunctival T cell populations in allogeneic hematopoietic stem cell transplant (HSCT) patients after instillation of daily topical cyclosporine-A (CsA) 0.1% cationic emulsion (Ikervis), and to evaluate patients' tolerance to these eye drops.

METHODS

Nineteen participants were prescribed Ikervis prophylaxis once daily to both eyes from 3-5 weeks pre-HSCT to 12 months post-HSCT. The outcome measure was conjunctival T cell proportions from flow cytometry after impression cytology. Covariates included visual acuity, intraocular pressure, slit lamp and fundal examination, dry eye (SPEED) and quality of life questionnaires, non-invasive keratograph tear break-up time (NIKBUT), conjunctival redness, meibography, lipid thickness, Schirmer test, tear cytokines, fluorescein staining, tear osmolarity, and meibomian gland expressibility.

RESULTS

The conjunctival T cell analysis showed either stable or decreased proportions of conjunctival CD4 T cells at the last visit from baseline in compliant patients. CD4 proportions were increased in non-compliant patients and in the single patient who developed ocular graft-versus-host disease (GVHD). All patients were tolerant to Ikervis but 6/19 were not compliant. In the majority of patients, vision did not affect activities of daily living. Pre- and post-HSCT up to the last study visit, there was no statistically significant change in clinical covariates. Only one participant developed ocular GVHD at 9 months post-HSCT.

CONCLUSION

Superficial conjunctival T cell profile reflects compliance to daily topical Ikervis eye drops and clinical ocular surface parameters in allogenic HSCT patients. Tolerance is comparable to other formulations of topical CsA in the first 12 months.

CLINICALTRIALS

GOV IDENTIFIER

NCT04636918. URL: https://clinicaltrials.gov/ct2/show/NCT04636918?cond=ocular+Graft+Versus+Host+Disease&cntry=SG&draw=2&rank=2 .

Polymorphisms in Lymphotoxin-Alpha as the "Missing Link" in Prognosticating Favourable Response to Omega-3 Supplementation for Dry Eye Disease: A Narrative Review

Elements of inflammation are found in almost all chronic ocular surface disease, such as dry eye disease. The chronicity of such inflammatory disease speaks to the dysregulation of innate and adaptive immunity. There has been a rising interest in omega-3 fatty acids to attenuate inflammation. While many cell-based (in vitro) studies verify the anti-inflammatory effects of omega-3, different human trials report discordant outcomes after supplementation. This may be due to underlying inter-individual differences in inflammatory cytokine metabolism (such as tumor necrosis factor alpha (TNF-α)), in which genetic differences might play a role, such as polymorphisms in the lymphotoxin alpha (LT-α) gene. Inherent TNF-α production affects omega-3 response and is also associated with LT-α genotype. Therefore, LT-α genotype might predict omega-3 response. Using the NIH dbSNP, we analyzed the relative frequency of LT-α polymorphisms among various ethnicities, each weighted by the genotype's probability of positive response. While the probability of response for unknown LT-α genotypes are 50%, there is greater distinction in response rates between various genotypes. Hence, there is value in genetic testing to prognosticate an individual's response to omega-3.

The association between altered intestinal microbiome, impaired systemic and ocular surface immunity, and impaired wound healing response after corneal alkaline-chemical injury in diabetic mice

Purpose

We aim to investigate the effect of sustained hyperglycemia on corneal epithelial wound healing, ocular surface and systemic immune response, and microbiome indices in diabetic mice compared to controls after alkaline chemical injury of the eye.

Methods

Corneal alkaline injury was induced in the right eye of Ins2^Akita (Akita) mice and wild-type mice. The groups were observed at baseline and subsequently days 0, 3, and 7 after injury. Corneal re-epithelialization was observed under slit lamp with fluorescein staining using a cobalt blue light filter. Enucleated cornea specimens were compared at baseline and after injury for changes in cornea thickness under hematoxylin and eosin staining. Tear cytokine and growth factor levels were measured using protein microarray assay and compared between groups and time points. Flow cytometry was conducted on peripheral blood and ocular surface samples to determine CD3+CD4+ cell count. Fecal samples were collected, and gut microbiota composition and diversity pattern were measured using shotgun sequencing.

Results

Akita mice had significantly delayed corneal wound healing compared to controls. This was associated with a reduction in tear levels of vascular endothelial growth factor A, angiopoietin 2, and insulin growth factor 1 on days 0, 3, and 7 after injury. Furthermore, there was a distinct lack of upregulation of peripheral blood and ocular surface CD3+CD4+ cell counts in response to injury in Akita mice compared to controls. This was associated with a reduction in intestinal microbiome diversity indices in Akita mice compared to controls after injury. Specifically, there was a lower abundance of Firmicutes bacterium M10-2 in Akita mice compared to controls after injury.

Conclusion

In diabetic mice, impaired cornea wound healing was associated with an inability to mount systemic and local immune response to ocular chemical injury. Baseline and post-injury differences in intestinal microbial diversity and abundance patterns between diabetic mice and controls may potentially play a role in this altered response.

Investigation on oral nursing of elderly patients and prognosis of patients

OBJECTIVE

To understand the oral care status of elderly inpatients in various departments, analyze the existing problems, and provide a basis for further improving the oral care practices and promoting the oral health of elderly patients.

PATIENTS AND METHODS

This study intends to investigate the oral care status of patients in a tertiary hospital in Chongqing. This study was divided into two phases, the first phase was designed as a cross-sectional study. Our aim was to explore the implementation status of oral care in each department. The second phase of this study was to explore the correlation between patient oral care and patient outcomes.

RESULTS

We extracted a total of 9,164 cases of elderly discharged patients. Primary care patients were mainly distributed in various general wards, among which orthopedics was the most frequent, accounting for 30.19%. The oral care doctor order rate of the patients with premium care was 80.21%, and the rate of oral care orders of the primary care patients was only 2.10%. The study analysis found that among surgical and intensive care unit (ICU) patients, patients in high-frequency group and low-frequency group were significantly better than that of patients without oral care in terms of overall survival.

CONCLUSIONS

The oral care is still insufficient, and the frequency of use is relatively infrequent. This study also found that oral care can improve patient outcomes and reduce the incidence of ventilator-associated pneumonia (VAP).

Shotgun metagenomic sequencing analysis of ocular surface microbiome in Singapore residents with mild dry eye

The ocular surface microbiome has implications for ocular surface inflammation and immunology. Previous shotgun metagenomics analyses were performed in China, showing results that differed according to environment and age. Patients with Sjogren's syndrome were reported to have altered conjunctival microbiome, but such studies have not been done in milder dry eye. The aim of this study is to describe the conjunctival microbiome in people with mild dry eye in Singapore. Samples were collected from 14 participants with mild dry eye and 10 age-matched comparison participants recruited from Singapore National Eye Centre (SNEC) clinics. Shotgun metagenomic sequencing analysis was employed to evaluate the conjunctival microbiome composition. Proteobacteria formed the predominant phylum in the conjunctiva. As in a study from a coastal city in China, Achromobacter spp. was numerically most abundant. Compared to age-matched controls, the conjunctival microbial composition in mild dry eye was similar. Several microorganisms, including Streptococcus spp. increased in representation with age, and the abundance of Staphylococcus correlated with Schirmer readings. In addition, when cultured corneal epithelial cells were exposed to three strains of Achromobacter xylosoxidans, cytokines such as TNF-α and IL-6 were upregulated in the cell lysates and supernatants. Ourresults suggest that age is an important factor that affects composition of the conjunctival microbiome, and relative abundance of specific microorganism may vary according to the environment of the human host.

Topical Omega-3 Fatty Acids Eyedrops in the Treatment of Dry Eye and Ocular Surface Disease: A Systematic Review

Dry eye is a common inflammatory condition of the ocular surface. While oral omega-3 supplementation for its treatment has been extensively studied, recent large-scale studies have cast doubt on their efficacy. However, efficacy of topical omega-3 has yet to be reviewed. We performed a systematic search of PubMed, Embase, and Cochrane databases for all studies evaluating topical omega-3 in dry eye. Five human and five animal studies were included. Of the five human studies, two were on dry eye disease (DED), one was on contact lens discomfort, and two were on patients undergoing corneal collagen crosslinking. In humans, there is promising evidence for improved ocular surface staining and tear break-up time compared to controls, equivocal evidence for improvements to ocular surface symptoms and meibomian gland dysfunction, and no effect on increasing tear production. Data from animal models largely agree with these findings, and further reveal decreased inflammatory cytokines and monocyte infiltration. Our review suggests that topical omega-3 is a promising treatment for dry eye, but also points to the paucity of evidence in this field. Further trials in humans are required to characterize effects of topical omega-3 and optimize its dosage.

[A prospective randomized controlled study on the repair of skin and soft tissue defect in functional areas of children with full-thickness skin grafts from different sites of abdomen]

Objective: To compare and analyze the effect of repairing small skin and soft tissue defect wounds in functional areas of children with full-thickness skin grafts from different sites of abdomen. Methods: A prospective randomized controlled study was conducted. From January 2019 to June 2020, 60 female children with small skin and soft tissue defects in functional areas requiring full-thickness skin grafting, who met the inclusion criteria, were admitted to the First Affiliated Hospital of Air Force Medical University. According to the random number table, the children were divided into two groups, with 28 cases left in lateral abdomen group aged 5 (3, 8) years and 29 cases in lower abdomen group aged 5 (3, 7) years after the exclusion of several dropped-out children in follow-up. In lower abdomen group, 20 (12, 26) cm2 wounds of children were repaired with (24±10) cm2 full-thickness skin graft from transverse skin lines in the inferior abdomen area, while in lateral abdomen group, 23 (16, 32) cm2 wounds of children were repaired with (24±9) cm2 full-thickness skin graft from below the umbilical plane to above the groin in the lateral abdomen area. All the children were treated with continuous intradermal suture at the donor site incision and received continuous negative pressure treatment of -10.64 to -6.65 kPa in the donor and recipient areas after operation. The donor site was treated with a medical skin tension-reducing closure device since post-surgery day (PSD) 7. The use of medical skin tension-reducing closure device at the donor site, postoperative complications and suture removal time of the donor area were recorded, and the incidence of complications was calculated. On PSD 7, a self-designed efficacy satisfaction questionnaire was used to investigate the parents' satisfaction with the curative effect of their children. In post-surgery month (PSM) 1 and 6, Vancouver scar scale (VSS) was used to evaluate the scar at the donor site, and the VSS score difference between the two time points was calculated; the scar width at the donor site was measured with a ruler, and the scar width difference between the two time points was calculated. Data were statistically analyzed with independent sample t test or Cochran & Cox approximate t test, Mann-Whitney U test, and Fisher's exact probability test. Results: The proportion of children in lateral abdomen group who used the medical skin tension-reducing closure device in the donor area for equal to or more than 4 weeks after surgery was significantly higher than that in lower abdomen group (P<0.05). On PSD 7, there was one case of partial incision dehiscence in the donor area, one case of peripheral skin redness and swelling in the donor area, and one case of fat liquefaction in the donor area in lateral abdomen group, and one case of partial incision dehiscence in the donor area in lower abdomen group. The incidence of postoperative complications at the donor site of children in lower abdomen group was significantly lower than that in lateral abdomen group (P<0.05). Compared with that in lateral abdomen group, the suture removal time at the donor site of children after surgery in lower abdomen group was significantly shorter (t'=17.23, P<0.01). On PSD 7, the satisfaction score of parents with the curative effect of their children in lower abdomen group was significantly higher than that in lateral abdomen group (t'=20.14, P<0.01). In PSM 1 and 6, the VSS scores of scar at the donor site of children in lower abdomen group were 2.7±0.9 and 2.8±1.0, respectively, which were significantly lower than 7.1±2.2 and 9.1±2.7 in lateral abdomen group (with t values of 10.00 and 11.15, respectively, P<0.01). In PSM 6, the VSS score of scar at the donor site of children in lateral abdomen group was significantly higher than that in PSM 1 (t=3.10, P<0.01), while the VSS score of scar at the donor site of children in lower abdomen group was not significantly higher than that in PSM 1 (P>0.05). The VSS score difference of scar at the donor site of children in lateral abdomen group was significantly greater than that in lower abdomen group (Z=-8.12, P<0.01). In PSM 1 and 6, the scar widths at the donor site of children in lower abdomen group were 2.0 (1.0, 2.0) and 2.0 (2.0, 3.0) mm, respectively, which were significantly narrower than 6.0 (4.0, 10.0) and 8.5 (5.0, 12.0) mm in lateral abdomen group (with Z values of -13.41 and -14.70, respectively, P<0.01). In PSM 6, the scar width at the donor site of children in lateral abdomen group was significantly wider than that in PSM 1 (Z=-2.79, P<0.01), while the scar width at the donor site of children in lower abdomen group was not significantly wider than that in PSM 1 (P>0.05). The difference of scar width at the donor site of children in lateral abdomen group was significantly greater than that in lower abdomen group (Z=-14.93, P<0.01). Conclusions: The use of full-thickness skin grafts from the lower abdomen to repair small skin and soft tissue defect wounds in functional areas of children, especially girls, is effective, simple and easy to operate, and conforms to the principle of aesthetic repair. Compared with transplantation with full-thickness skin graft from the lateral abdomen, lower abdominal full-thickness skin grafting has a low incidence of donor site complications and no obvious scar hyperplasia, which is worthy of clinical promotion.

Patient Medication Preferences for Managing Dry Eye Disease: The Importance of Medication Side Effects

Objectives

The side effects of dry eye medications can lead to medication non-adherence and, eventually, to poor outcomes. This study aimed to quantify to what extent the side effects of dry eye disease (DED) medications (burning/stinging sensation and blurring) are important to patients compared to medication benefits or costs.

Methods

Patients diagnosed with DED were recruited at a referral eye center in Singapore (n = 139). This study utilized a Discrete Choice Experiment where patients were presented with 10 choice tasks where they were asked to choose between their current medication (or no medication), and two hypothetical medications that varied based on five attributes: duration of burning/stinging, duration of blurring, time to medication effectiveness, medication frequency, and out-of-pocket cost. The main outcomes were relative attribute importance and predicted uptake.

Results

Latent class logistic regressions found two groups with distinct preferences. For both classes, duration of burning/stinging (Class 1 = 23%, Class 2 = 29%) and cost (Class 1 = 24%, Class 2 = 27%) were the most important attributes while duration of blurring (Class 1 = 15%, Class 2 = 9%) was the least important. The predicted uptake of a medication increased 18 percentage-points when burning/stinging duration decreased from 2 h to a few minutes. The predicted uptake for new medications was lowest for those on medication with well-controlled symptoms and highest for those who were not on medication and could not control their symptoms effectively.

Conclusion

This study showed that duration of burning/stinging was an important factor when choosing medications. Incorporating patient preferences in medication decisions can potentially improve patient acceptance of a treatment regimen.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40271-022-00586-8.

Evaluation of ocular surface and tear function - A review of current approaches for dry eye

An increasing prevalence of dry eye disease in the past decade has resulted in a greater focus on diagnostic methods for this condition. There has been a proliferation of technologies that attempt to quantify various aspects of tear function and ocular surface health. However, a cost-effective, simple, and efficient method remains elusive. In the Indian context, the majority of these patients present to the general ophthalmologist, and a clinical approach that is quick and easy to perform would allow widespread usage for accurate diagnosis. This article reviews currently available methods and their relevance to the general ophthalmologist.

Cicatricial Conjunctivitis and Concurrent Clinical Features: A Case Study

Purpose:

We report a case of cicatricial conjunctivitis to illustrate the clinical approach for management of such a case. This is a 52-year-old Chinese man who presented with bilateral red eyes associated with itching for a year. He had a history of chronic itchy rash in the chest and the arms. Otherwise there was no history of autoimmune disease, asthma, sinusitis, or drug allergy. On examination, he had diffuse hyperemia over both conjunctivae, with symblepharon involving the inferior bulbar and palpebral conjunctivae, associated with cicatrization of the caruncles, and obliteration of inferior lacrimal puncta. There were mild subtarsal papillary reaction with Meibomian gland dysfunction and presence of inferior mis-directed eyelashes. The corneas showed multiple foci of superficial epitheliopathy. A clinical diagnosis of chronic cicatricial conjunctivitis was made, with differential diagnosis of chronic atopic allergic conjunctivitis. Conjunctival biopsy was performed from the inferior conjunctival adhesions and it showed patchy chronic stromal inflammation with focal lymphoplasmacytic sub-epithelial infiltrates and loss of goblet cells. The stroma shows marked fibrosis, with no evidence of mast cells or eosinophils. In particular, there were no deposits of IgA, IgM, C3, and fibrinogen in the basement membrane. The patient was treated with topical loteprednol, glucocorticoids and artificial tears, and his symptoms improved after treatment.

Conclusion:

We present a man with cicatricial conjunctivitis with chronic subconjunctival inflammation and fibrosis but no immune deposits in the conjunctival basement membrane on histology, to illustrate the clinical approach and diagnostic challenges in managing such a case.

The Role of Nervous System and Immune System in Herpes Zoster Ophthalmicus Dissemination and Laterality - Current Views

PURPOSE

Herpes zoster ophthalmicus (HZO) is a sight-threatening condition that is defined as HZ involving the ophthalmic division of the trigeminal nerve. Cases of bilateral HZO in recent literature question the notion of HZO being a strictly unilateral disease. Its pathogenesis is a topic of debate and current literature on VZV dissemination lacks insight into the underlying immunology. This review focuses on novel research in immunology of HZO and aims to formulate hypotheses of spread of lesions through the CNS.

METHODS

A literature search was conducted on Entrez PubMed using the search terms "bilateral" and "herpes zoster ophthalmicus". Articles on ("Immunology" or "immune cells") and "herpes zoster ophthalmicus" were also searched for. Articles published from January 1942 to April 2020 that were in English language were included.

RESULTS

Our findings revealed that hypothesised mechanisms of dissemination causing bilateral ocular disease include transmission from nerves to vessel walls, the synergistic action of the immune and nervous systems through the action of substance P and the von Szily reaction.

CONCLUSIONS

These mechanisms may be investigated using newer models of animal experimentation. It is imperative to define the molecular mechanisms behind VZV transmission to improve methods of identification, treatment, and prevention of HZO.

Dry eye disease and proteomics

Dry eye disease (DED) is a highly prevalent disease worldwide mostly associated with age, though other factors such as screen use and contact lens wear explain why it is increasingly diagnosed in younger people. DED also disproportionately affects women. Symptoms include eye dryness, burning, pain and sensitivity to light that can significantly affect quality of life. This condition may progress to cause lasting damage to the ocular surface if left untreated. Currently, diagnosis is through assessment of signs and symptoms determined by clinical tests and questionnaires. However, there is considerable overlap between normal and DED result distributions of currently available metrics as signs and symptoms fluctuate over time and with disease severity. Importantly, the non-targeted approach of proteomics means that significant changes in novel proteins may be discovered. Proteomics is a powerful tool that has been applied to the field of DED to understand changes at a biochemical level, uncover new disease biomarkers and determine the success of clinical interventions. While individual proteins may not be sensitive enough when used as single biomarkers, proteomics opens the possibility to uncover several relevant proteins that may be combined in a panel to provide more accurate diagnostic value i.e. parallel testing. In this review we discuss the use of proteomics in DED research and the potential for application of proteomic results in the clinic. We also identify shortcomings and future avenues for research.

Impact of Incomplete Blinking Analyzed Using a Deep Learning Model With the Keratograph 5M in Dry Eye Disease

Purpose

To establish a deep learning model (DLM) for blink analysis, and investigate whether blink video frame sampling rate influences the accuracy of analysis.

Methods

This case-controlled study recruited 50 dry eye disease (DED) participants and 50 normal subjects. Blink videos recorded by a Keratograph 5M, symptom questionnaires, and ocular surface assessments were collected. After processing the blink images as datasets, further training and evaluation of DLM was performed. Blink videos of 30 frames per second (FPS) under white light, eight FPS extracted from white light videos, and eight FPS under infrared light were processed by DLM to generate blink profiles, allowing comparison of blink parameters, and their association with DED symptoms and signs.

Results

The blink parameters based on 30 FPS video presented higher sensitivity and accuracy than those based on eight FPS. The average relative interpalpebral height (IPH), the frequency and proportion of incomplete blinking (IB) were much higher in DED participants than in normal controls (P < 0.001). The IB frequency was closely associated with DED symptoms and signs (|R| ≥ 0.195, P ≤ 0.048), as was IB proportion and the average IPH (R ≥ 0.202, P ≤ 0.042).

Conclusions

DLM is a powerful tool for analyzing blink videos with high accuracy and sensitivity, and a frame rate ≥ 30 FPS is recommended. The IB frequency is indicative of DED.

Translational Relevance

The system of DLM-based blink analysis is of great potential for the assessment of IB and diagnosis of DED.

Orthokeratology Lens Wear for 2 Years in Children Did Not Alter Tear Film Lipid Thickness by Non-Invasive Interferometry

Purpose

Previous studies suggest that overnight orthokeratology (OOK) may be detrimental to tear function. We aimed to investigate the effect of OOK on lipid layer thickness (LLT), blink pattern, and meibomian gland and elucidate the relationship of these variables.

Methods

Thirty-seven participants who wore OOK lenses every night for at least 2 years and twenty-four healthy non-contact lens wearers (controls) were enrolled in this retrospective study. LipiView interferometry, blink pattern analysis, the ocular surface status, and morphology and function of the meibomian gland were determined.

Results

The OOK group and healthy controls had similar LLT, blink patterns, ocular surface status, and the function of the meibomian gland. OOK participants demonstrated higher meiboscore in the lower eyelids (p < 0.05) but not in the upper eyelids. Within the OOK group, LLT was significantly impacted by the partial blink rate (p < 0.05) and the total score of the upper meibomian gland (p = 0.10).

Conclusions

Wearing OOK for 2 or more years increased lower eyelid meibomian gland dropout but did not have a reduction of LLT.

Assessment and Management of Dry Eye Disease and Meibomian Gland Dysfunction: Providing a Singapore Framework

ABSTRACT

The purpose of this article is to provide a framework for general ophthalmologists in Singapore to manage dry eye. This framework considers the evidence in the literature as well as recommendations from expert panels such as the Tear Film & Ocular Surface Society Dry Eye Workshop II and the Asia Cornea Society Workgroup.This article covers the assessment of patient medical history and ask triage questions to identify local and systemic causes of dry eye disease (DED), excluding other possible causes, as well as the risk factors for DED and ocular surface inflammation. Evaluation of clinical signs to establish the diagnosis of DED and differentiation from other causes of irritable, red eyes are described. Tests for understanding the underlying disease processes and severity of DED are also presented.Management of dry eye should involve patient education and engagement. Information about the natural history and chronic nature of DED should be provided to improve long-term management of the disease and enhance compliance. Aggravating factors should be removed or lessened.We provide a guide to determine the most appropriate treatment (or combination of treatments) based on the severity and cause(s) of the disease, as well as the patient's needs and preferences. The aim of the management is to relieve ocular discomfort and prevent worsening of symptoms and signs, as well as to optimize visual function and minimize structural ocular damage. We also discuss the systematic follow-up and assessment of treatment response, as well as monitoring side effects of treatment, bearing in mind continuous support and reassurance to patients.