Tingting Qian

Assessment of tear film stability in dry eye with a newly developed keratograph.

Purpose: To investigate the applicability of a newly developed corneal topographer in assessing tear film stability. Methods: This is a prospective, case–control study. Forty-four Chinese dry eye patients and 41 normal subjects were recruited. Noninvasive tear film break-up time (NI-BUT) was measured using a new method based on a corneal topographer equipped with modified scan software. The reliability of the measurements was determined. Then, the correlations between the NI-BUT and the traditional fluorescein tear film break-up time, Schirmer I test values, and inferior tear meniscus height measurements were determined. The receiver operating characteristic curve technique was used to evaluate the NI-BUT examination in the diagnosis of dry eye. Results: In total, a significant difference between the NI-BUT and the fluorescein tear film break-up time was found (3.2 ± 2.3 seconds vs. 5.2 ± 3.4 seconds; P < 0.001). The coefficient of variation and intraclass correlation coefficient values of NI-BUT were 12.8% and 0.93, respectively, for NI-BUT for intraobserver repeatability and 15.4% and 0.88, respectively for interobserver repeatability. The NI-BUT showed a good correlation with other dry eye examinations (all P < 0.05). In addition, the NI-BUT was significantly shorter in dry eye patients (2.0 ± 0.2 seconds) than in normal subjects (4.3 ± 0.3 seconds; P < 0.001). When the cutoff value was set at <2.65 seconds, the sensitivity and specificity of the test were 84.1% and 75.6%, respectively. Conclusions: Measurements of NI-BUT obtained with the newly developed corneal topographer may provide a simple, noninvasive screening test for dry eyes with acceptable sensitivity, specificity, and repeatability.

Corneal Epithelial Thickness Map in Long-Term Soft Contact Lenses Wearers

Purpose To map the corneal epithelial thickness in vivo with Fourier-domain optical coherence tomography in long-term soft contact lens (SCL) wearers. Methods This is a cross-sectional observational study. Forty eyes from 40 normal subjects who had never worn SCL and 40 eyes from 40 SCL wearers who had worn lenses for more than 2 years were enrolled. Corneal epithelium over the entire cornea was topographically imaged using a novel optical coherence tomography system. An epithelial thickness map was automatically generated. Epithelial thicknesses of the central 2-mm, paracentral 2- to 5-mm (P1), and midperipheral 5- to 6-mm (P2) zones were obtained. In addition, the epithelial map variability in P1 and P2 zones, including maximum − minimum (MAX − MIN), map SD, and coefficient of variation (CV), was measured and analyzed. Results The average epithelial thickness of the central, P1, and P2 zones was 54.4 ± 1.1 &mgr;m, 53.2 ± 2.2 &mgr;m, and 52.3 ± 2.0 &mgr;m, respectively, in normal eyes and 49.2 ± 1.9 &mgr;m, 48.8 ± 2.2 &mgr;m, and 48.7 ± 2.8 &mgr;m, respectively, in eyes wearing SCL. Compared with normal control subjects, eyes with long-term SCL had significantly thinner epithelial thickness in all three zones (p < 0.05). However, there was no difference in MAX − MIN, SD, and CV of P1 and P2 zones between two groups. In both groups, there was significant difference in the epithelial thickness among different sectors in the paracentral and midperipheral zones. Conclusions There is a decrease in epithelial thickness in subjects who wear SCL long term. Clinicians should take note of the nonuniformity of the paracentral and midperipheral corneal epithelium thicknesses. This method may be useful for detecting early changes in corneal epithelial thickness caused by long-term SCL wear.

Heightened expression of MICA enhances the cytotoxicity of NK cells or CD8+T cells to human corneal epithelium in vitro

BackgroundMajor-histocompatibility-complex class I-related chain A (MICA) antigens are the ligands of NKG2D, which is an activating or coactivating receptor expressed on human NK cells and CD8+T cells. We sought to determine whether MICA expression in human corneal epithelium (HCE) could affect the cytotoxicity mediated by NK cells or CD8+T cells.MethodsCell cultures of HCE were harvested from human donor eyes. Flow cytometric analysis and ELISA was performed to determine the levels of MICA expression on HCE. Then, HCE was transfected with a lentivirus vector expressing MICA and GFP. Flow cytometric analysis, RT-PCR, western blot and ELISA were performed to check the levels of MICA expression. For cytotoxicity testing, allogeneic NK cells and CD8+T cells were isolated from peripheral blood mononuclear cells of healthy volunteers by magnetic cell sorting. The cytolytic activity of NK cells and CD8+T cells was assessed against MICA-transfected HCE (NK cells: E:T ratio = 3:1; CD8+T cells: E:T ratio = 10:1) using the nonradioactive cytotoxicity detection kit lactate deshydrogenase.ResultsSurface expression of MICA on corneal epithelium was identified at a low level. A cell line of stable human MICA-transfected corneal epithelium was successfully established. Heightened expression of MICA on HCE was found to promote the cytotoxicity mediated by NK cells or CD8+T cells, which could be blocked by an anti-MICA antibody.ConclusionMICA molecules may contribute to cytotoxic responses mediated by activated immune effector cells in corneal epithelium immunity.

Medically uncontrolled conjunctival pyogenic granulomas: correlation between clinical characteristics and histological findings

Background Conjunctival pyogenic granulomas are commonly seen after ocular surgeries or at an ocular wound site. The aim of this study is to describe a novel histological classification for medically uncontrolled conjunctival pyogenic granulomas (MUCPG), and to explore whether the diversity in clinical features correlates to different histological subtypes of MUCPG. Methods This is an observational cross-section case series. We reviewed 46 consecutive patients with conjunctival pyogenic granulomas who did not respond to topical corticosteroids and underwent surgical excision from January 1, 2006 through December 31, 2015. Clinical features and histological findings were presented and analyzed. Results Ocular surgery, accidental injury, and chalazion were the main predisposing causes of MUCPG. The lesions tended to occur unilaterally on the bulbar conjunctiva. Forty patients (87%) presented an enrichment of inflammatory cells and proliferated capillaries in their pathological sections (inflammatory pattern). Six patients (13%) showed relatively few inflammatory cells and capillaries within fibrous stroma (fibrous pattern). Patients with the inflammatory pattern were older (p = 0.025) and tended to be located in bulbar conjunctiva (p = 0.002). The predisposing causes were also different between two histological subtypes (p = 0.007). Conclusions We found the correlation between clinical presentation and histological subtypes in patients with MUCPG, indicating this disease may need a new classification scheme.

Meibomian Gland Alteration in Patients with Primary Chronic Dacryocystitis: An In vivo Confocal Microscopy Study

Abstract Purpose: To evaluate meibomian gland (MG) alterations in patients with primary chronic dacryocystitis (PCD) by in vivo confocal microscopy (IVCM), and to correlate the finding with clinical presentation. Methods: Twenty-eight eyes with the diagnosis of PCD and their contralateral unaffected eyes were studied and compared with 27 normal controls. All subjects completed an Ocular Surface Disease Index questionnaire (OSDI) and underwent slit-lamp biomicroscopy examination, tear break-up time (BUT) measurements, fluorescein staining, Schirmer test I, and an IVCM examination of the MG. IVCM parameters, including the MG acinar unit density (MGAUD), periglandular inflammatory cell density (ICD), MG acinar unit longest diameter (MGALD), and MG acinar unit shortest diameter (MGASD) and their correlation with clinical data were analyzed. Results: The mean MG expressibility scores, BUT values, and staining scores were significantly worse in eyes with PCD compared with the contralateral clinically unaffected eyes and controls (p < 0.05). A significant decrease in MGAUD was observed in PCD eyes compared with the controls and the contralateral clinically unaffected eyes. Conversely, the mean ICD and MGASD values were significantly higher in the PCD eyes. There were no significant differences in mean MGALD value between the PCD eyes and the contralateral clinically unaffected eyes. In addition, there were significant changes in the IVCM parameters in the contralateral unaffected eyes compared with the controls, including MGAUD, ICD, MGALD, and MGASD. All IVCM parameters showed a strong, significant correlation with MG dropout grades, MG expressibility, fluorescein staining scores, and OSDI values (all p < 0.05). Conclusions: Patients with unilateral PCD demonstrated significant changes in MG as compared with the contralateral clinically unaffected eyes and controls. The MG function should be closely observed in these patients.

IFN-γ regulates the expression of MICA in human corneal epithelium through the miRNA-4448 and NFkB.

Purpose Major histocompatibility complex class I-related chain A (MICA), a non-classical major histocompatibility complex molecule, can stimulate or co-stimulate CD8+ T cells or natural killer (nk) cells, thus affecting cornea allograft survival. This study investigated IFN-γ regulation of MICA expression levels in human corneal epithelium by miRNA4448. Methods MICA expression levels in human corneal epithelial cells (HCECs) stimulated with IFN-γ were detected by qRT-PCR and an enzyme-linked immunosorbent assay, and differential miRNA expression levels were measured. qRT-PCR, Western blotting, and immunofluorescence staining revealed nuclear factor kappa B (NFκB)/P65 expression in IFN-γ-treated and miRNA4448-overexpressed HCECs. A luciferase reporter assay was used to predict the interaction between NFκB and MICA. Additionally, HCECs were transfected with MICA plasmid or treated with IFN-γ and NKG2D-mAb and cocultured with NK cells and CD8+ T cells. Cell apoptosis was measured using Annexin V/PI staining. qRT-PCR detected the expression of anti-apoptosis factor Survivin and apoptosis factor Caspase 3 in MICA-transfected and IFN-γ-treated HCECs after co-culturing with NK cells and CD8+ T cells. Results IFN-γ (500 ng/ml, 24 h) upregulated MICA expression in HCECs in vitro. Among six differentially expressed microRNAs, miRNA4448 levels decreased the most after IFN-γ treatment. The overexpression of miRNA4448 decreased MICA expression. miRNA4448 downregulated NFκB/P65 expression in IFN-γ-induced HCEC, and it was determined that NFκB/P65 directly targeted MICA by binding to the promotor region. A coculture with NK cells and CD8+ T cells demonstrated that MICA overexpression enhanced HCEC apoptosis, which could be inhibited by NKG2D-mAb. Simultaneously, Survivin mRNA expression decreased and Caspase3 mRNA expression increased upon the interaction between MICA and NK (CD8+ T) cells in HCECs. Conclusion IFN-γ enhances the expression of MICA in HCECs by modulating miRNA4448 and NFκB/P65 levels, thereby contributing to HCEC apoptosis induced by NK and CD8+ T cells. This discovery may lead to new insights into the pathogenesis of corneal allograft rejection.

Nasolacrimal recanalization as an alternative to external dacryocystorhinostomy for treating failed nasolacrimal duct intubation.

AbstractTo compare the surgical duration and clinical outcomes of nasolacrimal recanalization versus external dacryocystorhinostomy (DCR) in the treatment of failed nasolacrimal duct intubation.This is a retrospective, comparative, and interventional study. We evaluated the outcomes of 66 consecutive patients undergoing either nasolacrimal recanalization (n = 32) or DCR (n = 34) in a tertiary lacrimal disease referral center. Length of surgical duration, clinical outcomes, and rate of recurrence at 18 months postoperatively were compared.The mean surgical duration was 18.5 minutes (range, 15–25 minutes) for nasolacrimal recanalization and 48.2 minutes (range, 45–61 minutes) for DCR, respectively (P < 0.001). The rate of success was 84.4% in the recanalization group and 85.3% in the DCR group, respectively (P = 0.91). The time to recurrence was 2.6 ± 1.1 months in the recanalization group and 5.6 ± 2.1 months in the DCR group (P < 0.001). Five failed cases in each group received a secondary DCR surgery with the same resolution rate (40%). The absence of ocular discharge at baseline was a significant predictor for a successful outcome in the recanalization group (P = 0.04) but not in the DCR group (P = 0.63).Nasolacrimal recanalization is an effective, safe, and time-saving alternative to DCR for the treatment of failed nasolacrimal duct intubation. Clinicians should be cautious in patients with discharge.