Biomechanical evaluation of porcine lens capsule with and without nucleus after capsulotomy - Finite element analysis.

Previous studies have shown that the nucleus could offer structural support to the lens capsule. This study investigated the biomechanical performance of porcine lens with and without nucleus for 4 mm, 4.5 mm, 5 mm, 5.5 mm and 6 mm capsulotomy and its potential impact on the stretch ratio of capsular bag when the anterior capsulotomy edge was stretched. Our simulation results showed higher strain for the capsular bag with nucleus, which is crucial for the porcine lens to tolerate more stretch without failure. This simulation could support future study on the optimization of capsulotomy based on patient specific condition, that is, the geometry of lens.

Initial experiences of cataract & lens surgery in 1269 patients in outpatient clean rooms using a portable laminar air flow device.

BACKGROUND: In 2020, routine cataract surgery was halted in most countries due to the COVID-19 pandemic in order to reduce transmission. With a consequent lack of theatre space, we developed a safe cataract pathway in outpatient department clean rooms to minimize patient exposure and time spent in hospital using a sterile laminar air flow device. We describe our initial experiences of restarting elective cataract surgery in the UK outpatient setting, outside of the operating theatre environment. METHODS: This was a prospective consecutive study of our clinical practice. A sterile air zone unit, the Toul Meditech Operio Mobile device, was used to create a sterile surgical site in three separate outpatient clean rooms from May 2020 to December 2021 in different geographical locations within Herefordshire, UK. Observations of the time spent in the department and a formal patient satisfaction survey were carried out for the initial 100 patients. All patients were followed up to assess development of post-operative complications. RESULTS: 1269 patients were included in the study. No patients sustained post-operative infection (n = 0/1269, 0%). For the initial 100 patients, the average time spent within the department was 74.3 min (unilateral cases, range 45-115 min) and 93.1 min (bilateral, 55-135 min). Patient satisfaction was high. CONCLUSION: Initial results demonstrate a safe, efficient and effective cataract surgery pathway with high patient satisfaction by converting outpatient clean rooms into ophthalmic operating theatres using the Toul Meditech Operio Mobile.

Corneal Ectasia Risk And Percentage Tissue Altered In Myopic Patients Presenting For Refractive Surgery.

PURPOSE: A percentage tissue altered (PTA) score of ≥40% has been advocated as an independent indicator of post-operative ectasia risk following laser in-situ keratomileusis (LASIK). This study was performed to test the hypothesis that refractive procedures, such as laser-assisted sub-epithelial keratectomy (LASEK) or small incision lenticule extraction (SMILE), may alter the range of PTA, within which refractive corneal surgery can be safely performed. SETTING: Refractive department, tertiary ophthalmic hospital. DESIGN: Retrospective observational study. METHODS: Review of case notes was performed for patients who presented for refractive surgeries, other than LASIK. To determine the risk of corneal ectasia for each patient prior to refractive surgery, we estimated what each patient's PTA would have been if they had undergone LASIK. The Randleman Ectasia Risk Score System (ERSS) was also calculated. RESULTS: 114 eyes (66 patients) were included. 94 eyes underwent SMILE. 20 eyes underwent LASEK. A significant proportion of eyes had PTA ≥40% - SMILE eyes: up to 31.9%, LASEK eyes: up to 60.0% (at presumed LASIK flap of 120 µm). The maximum calculated PTA was up to 47.9% in the SMILE group and up to 51.5% in the LASEK group. Using ERSS, 12.8-16% of SMILE eyes and 15.0-80.0% of LASEK eyes would have been considered to have moderate-to-high ectasia risk. No post-surgical ectasia was observed at 3 years. CONCLUSION: SMILE and LASEK alter the range of PTA, within which corneal refractive surgery may be performed with a lower risk of developing post-operative corneal ectasia; a safe PTA threshold needs to be determined for these procedures before recommendations for clinical practice can be made.

Patient priorities in herpes simplex keratitis.

OBJECTIVE: Herpes simplex keratitis (HSK) is a sight-threatening disease and a leading cause of infectious corneal blindness. Involving patients in setting the research agenda maximises patient benefit and minimises research waste. With no published patient involvement exercises, patients' priorities in HSK are unclear. The objective of this study is to explore patients' priorities for research in HSK. METHODS: A literature review of publications in the year preceding recruitment of patients identified nine domains of research interest. A questionnaire was sent to participants asking them to rank these in order of priority. The ranking results were given a weighted-average score, and a thematic analysis was undertaken for the narrative data. RESULTS: Thirty-seven patients participated in the survey. Top priorities for patients were risk factors for recurrence of infection, diagnostic tests and treatment failure. The narrative data revealed three key clinical needs: difficulties in long-term symptom control, the need for rapid access care in acute infection and the desire for more accessible information. CONCLUSION: This study highlighted three major issues in our current approach to HSK. First, there may be a misalignment between research efforts and patient priorities. Second, high-quality patient information is not widely available. This may hamper patients' abilities to make informed decisions and contribute towards research. Third, clinical service priorities are of equal importance to patients as research. Researchers and clinicians are encouraged to address both needs in parallel.

Higher-Order-Aberrations Following Hyperopia Treatment: Small Incision Lenticule Extraction, Laser-Assisted In Situ Keratomileusis and Lenticule Implantation.

PURPOSE: To compare the postoperative higher-order-aberrations (HOAs) after hyperopic small incision lenticule extraction (SMILE), hyperopic laser-assisted in situ keratomileusis (LASIK), and lenticule implantation for correction of hyperopia. METHODS: Eighteen monkeys were divided to six groups: +2.00 D and +4.00 D hyperopic SMILE, +2.00 D and +4.00 D hyperopic LASIK (n = 6 eyes for each), and lenticule implantation with a -2.00 D and -4.00 D lenticule (n = 3 eyes for each). The corneal HOAs were evaluated preoperatively and 3-month postoperatively. RESULTS: At 3-month postoperatively, the spherical aberrations significantly increased toward negative direction in all +4.00 D groups (all P < 0.05). There was a significant change toward more negative values in the third-order vertical coma in the SMILE +4.00 D and LASIK +4.00 D groups (P = 0.026 and P = 0.036, respectively). There were also significant changes in the third-order horizontal trefoil (P = 0.034) and oblique secondary astigmatism (P = 0.012) in the LASIK +4.00 D group. In the eyes that underwent +4.00 D lenticule implantation, the fourth-order horizontal quatrefoil significantly increased (P = 0.029). In low hyperopia correction (+2.00 D), treatment with lenticule implantation tended to have less changes in HOAs, compared to the other two groups. CONCLUSIONS: In hyperopic SMILE, hyperopic LASIK or lenticule implantation surgery, significant induction of third- and fourth-order HOAs were seen in moderate hyperopia correction but not in low hyperopia correction. In low hyperopia treatment, lenticule implantation might offer a favorable trend in the aspect of HOAs. TRANSLATIONAL RELEVANCE: The results provided the knowledge of surgically induced HOAs and understanding of the effects of surgery in different types of hyperopic correction.

Hyperopic refractive correction by LASIK, SMILE or lenticule reimplantation in a non-human primate model.

Hyperopia is a common refractive error, apparent in 25% of Europeans. Treatments include spectacles, contact lenses, laser interventions and surgery including implantable contact lenses and lens extraction. Laser treatment offers an expedient and reliable means of correcting ametropia. LASIK is well-established however SMILE (small-incision lenticule extraction) or lenticule implantation (derived from myopic laser-correction) are newer options. In this study we compared the outcomes of hyperopic LASIK, SMILE and lenticule re-implantation in a primate model at +2D/+4D treatment. While re-implantation showed the greatest regression, broadly comparable refractive results were seen at 3-months with SMILE and LASIK (<1.4D of intended), but a greater tendency to regression in +2D lenticule reimplantation. Central corneal thickness showed greater variation at +2D treatment, but central thickening during lenticule reimplantation at +4D treatment was seen (-17± 27µm LASIK, -45 ± 18µm SMILE and 28 ± 17µm Re-implantation; p <0.01) with expected paracentral thinning following SMILE. Although in vivo confocal microscopy appeared to show higher reflectivity in all +4D treatment groups, there were minimal and inconsistent changes in inflammatory responses between modalities. SMILE and lenticule re-implantation may represent a safe and viable method for treating hyperopia, but further optimization for lower hyperopic treatments is warranted.

Corneal lenticule storage before reimplantation.

Purpose: To explore the optimal lenticule storage conditions that maintain lenticule integrity and clarity. Methods: A total of 99 lenticules obtained from myopic patients undergoing small incision lenticule extraction (SMILE) were divided into four combinations for short-term storage conditions: PBS, Dulbecco's Modified Eagle's Medium (DMEM), Optisol GS, or anhydrous glycerol. Two thirds of the lenticules were further stored for 4 weeks under eight different conditions. Clarity evaluation with transmittance measurements, cell-death assays with terminal deoxynucleotidyl transferase-mediated nick end labeling assay (TUNEL), collagen fibril spacing and necrotic response assessed with transmission electron microscopy (TEM), and immunohistochemistry analysis for human leukocyte antigens (HLAs) and CD45 for immunogenicity, and matrix metalloproteinase (MMP)-2 for keratocyte response, were undertaken at baseline, 48 h (short term), and 4 weeks (long term). Results: The TUNEL and immunogenicity results were comparable among the groups. The mean percentage of TUNEL-positive cells across all groups was 24.3% ± 11.8% and 62.9% ± 20.7% at the 48 h and 4 week time points, respectively. HLA-ABC+, HLA-DR+, and CD45+ cells were extremely rare, and MMP-2 expression ranged from non-detectable to minimal, under all conditions at all time points. Transmittance at 4 weeks was significantly different among groups with the greatest maintenance of clarity seen in the lenticules stored initially in DMEM at 4 °C for 48 h followed by cryopreservation in serum-free medium or glycerol at 4 °C followed by storage at room temperature. At TEM analysis at 4 weeks, the lenticules cryopreserved in liquid nitrogen, regardless of storage solutions, had significantly narrower inter-fibrillar distance than controls, while glycerol-preserved lenticules, at either room temperature or -80 °C, maintained the inter-fibrillar distance. Conclusions: Clarity, structural integrity, and low immunogenicity under various conditions, at 4 °C or room temperature for short-term storage, offer encouragement for lenticule storage. It can be undertaken without access to s specialized and potentially expensive laboratory setup at least within the first 48 h before transportation to larger facilities for long-term storage.

Performing Reliable Lens Capsulotomy in the Presence of Corneal Edema With a Femtosecond Laser.

Purpose: To determine the effects of the Ziemer LDV Z8 liquid interface femtosecond laser platform during capsulotomy under different energy settings in the presence of corneal edema. Methods: Cadaveric porcine eyes (n = 36) employed at less than 6 and greater than 24 post enucleation hours to simulate clear/edematous corneas, underwent capsulotomy with the Ziemer LDV Z8 femtosecond laser (5-mm diameter, energy 90%, 130%, or 150%). Lens capsules were removed for evaluation by scanning electron microscopy and rupture strengths determined by the single column universal testing system. Following ethical approval, 23 patients had lens capsules removed during routine cataract surgery following manual or Z8 capsulotomy and subjected to TUNEL assay. Results: There was no difference in edge morphology or rupture strength (120, 113, and 118 mN at increasing energy, P = 0.42) in the clear cornea. Only 50% of capsulotomies succeeded at 90% energy in an edematous cornea, improving with increased energy (75% completion at 130%, 100% at 150%). Rupture strength in edematous corneas was not significantly different at 112, 133, and 114 mN for 90%, 130%, and 150%, respectively (P = 0.3). In human samples, increased TUNEL-positive cells were seen at 130% energy, but not at 150% (0.0 manual vs. 0.2 [90%] vs. 2.1 [130%] vs. 0.6 [150%], P < 0.05). Conclusions: Because of the low energy delivered by a femtosecond nanojoule platform, even incremental increases in energy appeared to have minimal effect on lens capsule morphology and strength and negligible influence on cell death. Furthermore, increasing energy appeared to enhance consistency and the ability to complete a capsulotomy in an edematous cornea.

Nerve regeneration by human corneal stromal keratocytes and stromal fibroblasts.

Laser refractive surgeries reshape corneal stroma to correct refractive errors, but unavoidably affect corneal nerves. Slow nerve regeneration and atypical neurite morphology cause desensitization and neuro-epitheliopathy. Following injury, surviving corneal stromal keratocytes (CSKs) are activated to stromal fibroblasts (SFs). How these two different cell types influence nerve regeneration is elusive. Our study evaluated the neuro-regulatory effects of human SFs versus CSKs derived from the same corneal stroma using an in vitro chick dorsal root ganglion model. The neurite growth was assessed by a validated concentric circle intersection count method. Serum-free conditioned media (CM) from SFs promoted neurite growth dose-dependently, compared to that from CSKs. We detected neurotrophic and pro-inflammatory factors (interleukin-8, interleukin-15, monocyte chemoattractant protein-1, eotaxin, RANTES) in SFCM by Bio-Plex Human Cytokine assay. More than 130 proteins in SFCM and 49 in CSKCM were identified by nanoLC-MS/MS. Proteins uniquely present in SFCM had reported neuro-regulatory activities and were predicted to regulate neurogenesis, focal adhesion and wound healing. Conclusively, this was the first study showing a physiological relationship between nerve growth and the metabolically active SFs versus quiescent CSKs from the same cornea source. The dose-dependent effect on neurite growth indicated that nerve regeneration could be influenced by SF density.

Defining Ocular Surface Disease Activity and Damage Indices by an International Delphi Consultation.

PURPOSE: Unifying terminology for the description of ocular surface disease (OSD) is vital for determining treatment responses and ensuring robust clinical trial outcomes. To date, there are no agreed parameters describing 'activity' and 'damage' phases of disease. METHODS: A working group of international experts in OSD, oculoplastics, and uveitis from a range of backgrounds (university, teaching, district general and private hospitals) participated in a modified Delphi consensus-building exercise (October 31, 2011 to March 20, 2015). Two steering group meetings took place in which factors based upon published literature were discussed and supplemented with anonymous web-based questionnaires to refine clinical indices according to 'activity' (reversible changes resulting directly from the inflammatory process) and/or 'damage' (persistent, >6 months duration) changes resulting from previously active disease that are cumulative and irreversible). RESULTS: The recommended set of clinical parameters for the assessment of OSD encompasses 68 clinical indices and 22 ancillary grading tools (in parenthesis) subdivided by anatomical domain as follows: 4(4) tear-film, eyelid 21(3), 17(3) conjunctiva, 15(10) cornea and 11(2) Anterior Chamber/Sclera. Of these; 17(2) were considered as measures of clinical activity, 27(3) as damage, 1(8) as measures of both activity and damage. Twenty-three clinical descriptors and 9 tools did not reach the threshold for inclusion into the main standard set. These were defined as 'second tier' parameters for use in special clinical settings. CONCLUSION: These core parameters provide the first description of 'activity' and 'damage' relevant to OSD and provide a platform for the future development of scoring scales for each parameter.

Conjunctival Neutrophils Predict Progressive Scarring in Ocular Mucous Membrane Pemphigoid.

PURPOSE: Ocular mucous membrane pemphigoid (OcMMP) is a rare autoimmune disorder resulting in progressive conjunctival fibrosis and ocular surface failure leading to sight loss in up to 50%. This study was designed to optimize an ocular surface sampling technique for identification of novel biomarkers associated with disease activity and/or progressive fibrosis. METHODS: Fifty-seven patients with OcMMP underwent detailed examination of conjunctival inflammation and fibrosis using fornix depth measurement. Ocular surface impression cytology (OSIC) to sample superior bulbar conjunctiva combined with flow cytometry (OSIC-flow) profiled infiltrating leukocytes. Profiles were compared with healthy controls (HC) and disease controls (primary Sjögren's syndrome, pSS). Thirty-five OcMMP patients were followed every 3 months for 12 months. RESULTS: Overall neutrophils were elevated in OcMMP eyes when compared to pSS or HC (109 [18%] neutrophils/impression [NPI]; 2 [0.2%]; 6 [0.8%], respectively [P < 0.0001]) and in OcMMP patients with no visible inflammation when compared with HC (44.3 [7.9%]; 5.8 [0.8%]; P < 0.05). At 12 months follow-up, 53% of OcMMP eyes progressed, and this was associated with baseline conjunctival neutrophilia (P = 0.004). As a potential biomarker, a value of 44 NPI had sensitivity, specificity, and positive predictive values of 75%, 70%, and 73%, respectively. Notably, eyes with no visible inflammation and raised conjunctival neutrophils were more likely to progress and have a greater degree of conjunctival shrinkage compared to those without raised neutrophils. CONCLUSIONS: These data suggest that OSIC-flow cytometric analyses may facilitate repeated patient sampling. Neutrophils may act as a biomarker for monitoring disease activity, progressive fibrosis, and response to therapy in OcMMP even when the eye appears clinically uninflamed.

The effects of a low-energy, high frequency liquid optic interface femtosecond laser system on lens capsulotomy.

The introduction of femtosecond laser assisted cataract surgery (FLACS) is a paradigm changing approach in cataract surgery, the most commonly performed surgical procedure. FLACS has the potential to optimize the creation of an anterior lens capsulotomy, a critical step in accessing the cataractous lens. The merits of using a laser instead of a manual approach include a potentially more circular, consistent, and stronger aperture. In this study we demonstrated for the first time in both a porcine and human experimental setting that with a low energy, high repetition FLACS system, that a circular, smooth and strong capsulotomy was achievable. While there was no demonstrable difference in the resistance to rupture before or after the removal of the nucleus, larger capsulotomies had an increase in tensile strength. The LDV Z8 system appeared to create circular, rupture-resistant and smooth capsulotomies in both porcine and more importantly human globes.

Periodontitis prevalence and serum antibody reactivity to periodontal bacteria in primary Sjögren's syndrome: a pilot study.

AIMS: The aims of this study were as follows: (i) To assess the prevalence of periodontitis among patients with primary Sjögren's syndrome (pSS) and comparator groups of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). (ii) To perform a pilot study to compare serum antibody responses to 10 oral/periodontal bacteria in these patient groups and a historical comparator group of patients with periodontitis. MATERIALS AND METHODS: Standard clinical periodontal assessments were performed on 39 pSS, 36 RA and 23 OA patients and "In-house" antibody ELISAs for serum antibodies against 10 oral/periodontal bacteria were performed in these groups. RESULTS: Forty-six percent of the pSS group, 64% of the RA group and 48% of the OA group had moderate/severe periodontitis. These frequencies did not reach statistical significance between groups. Raised antibody levels to Prevotella denticola were found in the pSS, RA and periodontitis groups compared to the OA group. Significant between group differences were seen for Aggregatibacter actinomycetemcomitans, Prevotella intermedia and Campylobacter showae. None of these differences were specifically associated with pSS. CONCLUSION: This study showed no increase in periodontitis in pSS patients. Although the P. denticola data are of interest, identifying bacterial triggering factors for pSS will likely require alternative strategies including modern techniques such as microbiome analysis.

Cytokine production and antigen recognition by human mucosal homing conjunctival effector memory CD8+ T cells.

PURPOSE: Conjunctival epithelial T cells are dominated by CD3(+)CD56-TCRαß(+)CD8αß(+) lymphocytes. In this study we explored the antigen experience status, mucosal homing phenotype, cytokine expression, and viral antigen recognition of conjunctival epithelial CD8(+) T cells from healthy individuals. METHODS: Following ocular surface impression cytology, conjunctival cells were recovered by gentle agitation and analyzed by flow cytometry for cell surface markers, cytokine production (stimulated by phorbol 12-myristate 13-acetate [PMA]/ionomycin), and Epstein-Barr virus (EBV)/cytomegalovirus (CMV) immunodominant epitope recognition using major histocompatibility complex (MHC) class I peptide tetramers. RESULTS: In contrast to peripheral blood, conjunctival epithelial CD8(+) T cells were dominantly CD45RA(-)CCR7(-) effector memory cells, and the vast majority expressed the mucosal homing integrin αEß7. Conjunctival memory CD8(+) T cells maintained effector functions with the ability to secrete IFN-γ and expression of Granzyme B, although they expressed significantly reduced amounts per cell compared to peripheral blood T cells. Interestingly, herpetic virus-specific CD8(+) T cells recognizing epitopes derived from EBV and CMV could be detected in the conjunctival cells of healthy virus carriers, although they were generally at lower frequencies than in the peripheral blood of the same donor. Virus-specific conjunctival CD8(+) T cells were dominated by CD45RA(-)CCR7(-) effector memory cells that expressed αEß7. CONCLUSIONS: These data demonstrate that the majority of conjunctival epithelial CD8(+) T cells are mucosal homing αEß7(+) effector memory T cells, which can recognize viral epitopes and are capable of secreting Granzyme B and IFN-γ.

Neuron J is a rapid and reliable open source tool for evaluating corneal nerve density in herpes simplex keratitis.

PURPOSE: In vivo confocal microscopy (IVCM) demonstrates reduction in corneal sub-basal nerve density in herpes simplex keratitis (HSK). Image J is an open source image-analysis platform that can be combined with a nerve tracer, Neuron J. We sought to compare the reliability and speed of corneal nerve density quantification between these modalities and their relation to clinical damage. METHODS: A total of 16 eyes (14 patients) with chronic HSK was assessed clinically and by IVCM. Randomly ordered triplicate, representative images from the central cornea were presented to two masked observers and corneal sub-basal nerve density was measured using Image J/Neuron J. Agreement was quantified using intraclass correlation coefficients (ICC), Bland-Altman plots together with mean difference, and level of agreement (LoA). RESULTS: The median nerve density was measured at 7.1 mm/mm(2) (quartiles, 3.3-11.2), with Neuron-J demonstrating good intra-/interobserver agreement (ICC, 0.96-0.99; P < 0.001; mean difference, 0.1-1.4; LoA, <±3.3). Intraeye reliability was less consistent (mean difference, 1.7-2.3; LoA, ±8.8-9.8). Neuron J was highly comparable to Image J for both observers (ICC, 1.0; P < 0.001; mean difference, <0.2; LoA, ±<1.2) and significantly faster than Image J (median, 49 vs. 102 seconds, P < 0.001). Diminished nerve density was associated with corneal opacification and reduction in visual acuity (both P = 0.03). CONCLUSIONS: The IVCM combined with Neuron J affords objective, user-friendly, and fast quantification of corneal nerve damage in HSK. It provides semiobjective phenotyping of the sequelae of neurotrophic corneal damage and offers a potential tool for measuring vulnerability to relapse or additional infections. Further exploration in a larger longitudinal cohort is warranted.

Cortisol biosynthesis in the human ocular surface innate immune response.

Innate immune responses have a critical role in regulating sight-threatening ocular surface (OcS) inflammation. While glucocorticoids (GCs) are frequently used to limit tissue damage, the role of intracrine GC (cortisol) bioavailability via 11-beta-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) in OcS defense, remains unresolved. We found that primary human corneal epithelial cells (PHCEC), fibroblasts (PHKF) and allogeneic macrophages (M1, GM-CSF; M2, M-CSF) were capable of generating cortisol (M1>PHKF>M2>PHCEC) but in corneal cells, this was independent of Toll-like receptor (TLR) activation. While PolyI∶C induced maximal cytokine and chemokine production from both PHCEC (IFNγ, CCL2, CCL3, and (CCL4), IL6, CXCL10, CCL5, TNFα) and PHKF (CCL2, IL-6, CXCL10, CCL5), only PHKF cytokines were inhibited by GCs. Both Poly I∶C and LPS challenged-corneal cells induced M1 chemotaxis (greatest LPS-PHKF (250%), but down-regulated M1 11ß-HSD1 activity (30 and 40% respectively). These data were supported by clinical studies demonstrating reduced human tear film cortisol∶cortisone ratios (a biomarker of local 11ß-HSD1 activity) in pseudomonas keratitis (1∶2.9) versus healthy controls (1∶1.3; p<0.05). This contrasted with putative TLR3-mediated OcS disease (Stevens-Johnson Syndrome, Mucous membrane pemphigoid) where an increase in cortisol∶cortisone ratio was observed (113.8∶1; p<0.05). In summary, cortisol biosynthesis in human corneal cells is independent of TLR activation and is likely to afford immunoprotection under physiological conditions. Contribution to ocular mucosal innate responses is dependent on the aetiology of immunological challenge.

Defining the limits of normal conjunctival fornix anatomy in a healthy South Asian population.

PURPOSE: Quantifying the extent of conjunctival fibrosis for documentation of progression in conjunctival scarring disease is a clinical challenge. Measurement of forniceal foreshortening facilitates monitoring of these disorders. This study aims (1) to define the limits of the normal human conjunctival fornices and how these alter with age and (2) to provide normative data for upper and lower fornix depths (FDs) and fornix intercanthal distance (FICD) within a healthy South Asian, racially distinct population. DESIGN: Epidemiologic, cross-sectional study. PARTICIPANTS: A total of 240 subjects with national origins from South Asia, with no known ocular history and normal adnexal and conjunctival examination, aged 20 to 80 years. METHODS: An FICD modification of a custom-designed fornix depth measurer (FDM) was validated and used for measurement of both lower and upper FDs together with FICDs in 480 healthy eyes with no ocular comorbidities. Data were analyzed using repeated-measures analysis of variance and presented as means with 95% confidence intervals (CIs). MAIN OUTCOME MEASURES: Mean lower and upper FDs and FICD for the entire cohort, stratified according to age decade and sex. RESULTS: For this South Asian population, the overall upper and lower FDs were 15.3 mm (95% CI, 14.9-15.6) and 10.9 mm (95% CI, 10.7-11.1), respectively, with FICD defined as 32.9 mm (95% CI, 32.5-33.4) (upper) and 31.7 mm (95% CI, 31.3-32.1) (lower). With increasing age, a progressive reduction of all measured parameters (P < 0.001) was noted, with female subjects having significantly shallower fornices (upper FD, P < 0.001; lower FD, P < 0.001; upper FICD, P = 0.081; and lower FICD, P = 0.015). CONCLUSIONS: This is the first study to define the limits of normal upper FD and FICDs in any population group. Our study demonstrates sex variations and progressive conjunctival shrinkage with age. Although it provides important, objective data for normal forniceal anatomy, further study is recommended in other populations to confirm the generalizability of these data or to enable normal comparative datasets for the assessment of conjunctival scarring disorders among all anthropological groups.

Elevation of conjunctival epithelial CD45INTCD11b⁺CD16⁺CD14⁻ neutrophils in ocular Stevens-Johnson syndrome and toxic epidermal necrolysis.

PURPOSE: Ocular complications related to Stevens-Johnson Syndrome (SJS)-Toxic Epidermal Necrolysis (TEN) may persist and progress after resolution of systemic disease. This is thought to be related in part to persistent ocular innate-immune signaling. In this study, our aim was to characterize infiltrative conjunctival cellular profiles during acute (<12 months) and chronic (>12 months) disease. METHODS: Consecutive patients presenting with SJS-TEN over a 12-month period were followed for 1 year. Detailed clinical examination and conjunctival impression cell recovery was analyzed by flow cytometry for the presence of intraepithelial leukocytes and compared with healthy controls (n = 21). RESULTS: Ten patients were recruited of whom six had acute disease and five were classified as TEN (SCORTEN = 1, n = 4). Conjunctival inflammation was graded as absent/mild in a total of nine patients; but despite this, evidence of fornix shrinkage was observed in nine subjects. This inversely correlated with disease duration (P < 0.05). A reduction in percentage of CD8αß(+) T cells compared with controls (80% vs. 57%; P < 0.01) was associated with a corresponding increase in the number/percentage of CD45(INT)CD11b(+)CD16(+)CD14(-) neutrophils (186 vs. 3.4, P < 0.01, 31% vs. 0.8%, P < 0.001). Neutrophils inversely correlated with disease duration (r = -0.71, P = 0.03), yet there was no absolute change in the CD8αß(+) or neutrophil populations during the study period (P = 1.0). CONCLUSIONS: These data highlight that a neutrophilic infiltrate is present in mildly inflamed or clinically quiescent conjunctival mucosa in patients with ocular SJS-TEN, where neutrophil numbers inversely correlate with disease duration. Neutrophil persistence endorses the hypothesis of an unresolved innate-inflammatory process that might account for disease progression.

Aqueous humor suppression of dendritic cell function helps maintain immune regulation in the eye during human uveitis.

PURPOSE: Noninfectious uveitis is characterized by a dysregulated inflammatory or immune response in the eye. It is unclear whether this represents a failure of immune privilege or an overwhelming inflammatory drive that has exceeded the capacity of regulatory mechanisms that are still functioning. The authors investigated immune regulation in the human eye during intraocular inflammation (uveitis) and its impact on dendritic cell (DC) function and subsequent T-cell responses. METHODS: Myeloid DCs were isolated from the aqueous humor (AqH) and peripheral blood of patients with active uveitis and characterized by flow cytometry. The effect of uveitis AqH was interrogated in an in vitro model of peripheral blood monocyte-derived DCs from healthy controls. RESULTS: Myeloid DCs isolated from uveitic AqH were characterized by elevated major histocompatibility complex classes I and II (MHC I/II), but reduced CD86 compared with matched peripheral blood DCs. Exposure of peripheral blood monocyte-derived DCs from healthy controls to the inflammatory AqH supernatant recapitulated this phenotype. Despite interferon gamma (IFNγ)-dependent upregulation of MHC I, inflammatory AqH was overall suppressive to DC function, with reduced CD86 expression and diminished T-cell responses. This suppressive effect was equal to or greater than that induced by noninflammatory AqH, but was glucocorticoid independent (in contrast to noninflammatory AqH). CONCLUSIONS: These data indicate that the ocular microenvironment continues to regulate DC function during uveitis, despite IFNγ-driven upregulation of MHC expression, supporting the hypothesis that immune regulation within the eye is maintained during inflammation.