Qingfeng Liang

Corneal nerve structure and function in patients with non-sjogren dry eye: clinical correlations.

PURPOSE To evaluate the relationship between the in vivo confocal microscopic (IVCM) morphology of subbasal corneal nerves, corneal sensitivity, and clinical parameters in patients with non-Sjögren dry eye disease (NSDD). METHODS Forty-three patients with NSDD and 14 healthy age- and sex-matched control subjects were included. Each patient underwent an evaluation of ocular surface disease symptoms using the Ocular Surface Disease Index (OSDI); tear film break-up time (TBUT); corneal and conjunctival staining (Oxford scale); the Schirmer test; corneal sensation testing using the Cochet-Bonnet esthesiometer; and corneal subbasal nerve analysis with IVCM. One eye of each subject was included in the study. RESULTS Mean corneal sensitivity was significantly lower in the NSDD group as compared with the control group (P = 0.014). Corneal subbasal nerves showed significant changes in NSDD patients as compared with normal subjects: lower density (P < 0.001); increased tortuosity (P < 0.001); number of beadings (P < 0.001); and width (P = 0.041). In patients with NSDD, corneal subbasal nerve density was correlated to age (r = -0.352, P = 0.021); the Oxford scale (r = -0.486, P = 0.01); and central corneal sensitivity (r = 0.383, P = 0.041). The maximum length of nerve fibers within a frame (MaxL) was correlated to the OSDI (r = -0.265, P = 0.019) and the Oxford scale (r = -0.307, P = 0.039). In multivariate analysis after adjustment for age, corneal subbasal nerve density remained correlated to the Oxford score (P < 0.001). The Oxford score was also correlated to central corneal sensitivity (r = -0.304, P = 0.042). CONCLUSIONS NSDD patients have both structural and functional alterations of subbasal corneal nerves and these changes are related to the severity of dry eye.

Dynamic Change of Optical Quality in Patients With Dry Eye Disease

PURPOSE To evaluate the dynamic changes of optical quality in patients with dry eye disease (DED) by using a double-pass system. METHODS Fifty-six patients with DED and 35 control subjects were included in this study. Each patient underwent an evaluation of the ocular surface, using the Ocular Surface Disease Index, tear film breakup time (TBUT), corneal and conjunctival staining (Oxford scale), and Schirmer I test. Using the tear film analysis program of the Optical Quality Analysis System, we recorded the objective scatter index (OSI) every 0.5 seconds within a 20-second period with the subjects asked to blink freely. Several parameters were established to evaluate the dynamic alterations of optical quality and the effects of blinks: OSI standard deviation (SD), ΔOSI, ΔOSI/time, blinking change (BC), blinking frequency (BF), and tolerant limitation (TL). RESULTS Patients with DED had significant alterations of optical quality compared to control subjects. The ΔOSI, ΔOSI/time, BC, and BF were significantly higher and TL was significantly lower in DED patients than controls. Furthermore, the ΔOSI and ΔOSI/time were also significantly higher in patients with severe DED than patients with mild disease. In univariate analysis, both TBUT and corneal staining were correlated with ΔOSI, ΔOSI/time, and BC. In multivariate analysis, ΔOSI/time was correlated to the corneal staining score. CONCLUSIONS The double-pass system allowed the monitoring of the dynamic changes of optical quality in patients with DED. Optical quality should be evaluated in patients with DED because these alterations cannot be determined from the classical DED clinical tests.

Evaluation of Optical Coherence Tomography Meibography in Patients With Obstructive Meibomian Gland Dysfunction.

Purpose: To evaluate optical coherence tomography meibography (OCT-M) in patients with and without obstructive meibomian gland dysfunction (MGD) and to determine the relationship between OCT-M and ocular surface clinical tests. Methods: Twenty-two patients with MGD and 16 control subjects were included. Each patient underwent an evaluation of ocular surface disease symptoms, lid margin abnormality score, lipid layer thickness evaluation, and meibomian gland (MG) morphological changes using noncontact infrared meibography and OCT-M. OCT-M scans were acquired in 4 different locations. OCT-M parameters including the MG length and width and palpebral conjunctival thickness were evaluated. Results: Within the OCT-M parameters, the mean length and width of MGs were significantly decreased in patients with MGD (310 ± 60 &mgr;m and 214 ± 30 &mgr;m, respectively) compared with the control group (361 ± 53 &mgr;m, P = 0.041 and 264 ± 41 &mgr;m, P = 0.021, respectively). The mean conjunctival thickness was also significantly increased in patients with MGD (448 ± 68 &mgr;m) than in the control group (356 ± 59 &mgr;m, P = 0.03). The mean length of MGs was correlated with symptoms (r = 0.34, P = 0.034), and the mean MG width was correlated with tear film breakup time (r = −0.412, P = 0.009) and the lid margin abnormality score (r = 0.334, P = 0.038). Conclusions: The MG length and width were significantly decreased in patients with MGD than in the control group. These parameters were correlated to both ocular surface symptoms and clinical signs. This new imaging technique may be a useful tool for MGD evaluation.

Ocular Surface Epithelial Thickness Evaluation in Dry Eye Patients: Clinical Correlations.

Purpose. To evaluate the relationship between corneal and conjunctival epithelium thickness and ocular surface clinical tests in dry eye disease (DED) patients. Patients and Methods. Fifty-four patients with DED and 32 control subjects were included. Each patient underwent an ocular surface evaluation using the ocular surface disease index (OSDI), tear film break-up time (TBUT), corneal and conjunctival staining, tear film lipid layer analysis, and Schirmer test. The central corneal (CET), limbal (LET), and bulbar conjunctival epithelium thickness (BET) were acquired using spectral-domain optical coherence tomography (SD-OCT). Results. Compared to control subjects, mean BET was significantly thicker and mean LET was significantly lower in the DED group. There was no significant difference in mean CET between the two groups. The mean LET was correlated with OSDI and TBUT. The inferior LET was correlated with OSDI, Schirmer I test, TBUT, Oxford score, and corneal sensitivity. Mean BET was correlated with OSDI and TBUT, but not with Schirmer I test and Oxford score. Conclusions. In dry eye patients, a thinner limbal epithelium and a thicker bulbar conjunctival epithelium were observed. These changes were correlated to the severity of dry eye symptoms and tear film alterations.

Reis-Bücklers Corneal Dystrophy: A Reappraisal Using in vivo and ex vivo Imaging Techniques

Purpose: To characterize the phenotype of Reis-Bücklers corneal dystrophy (RBCD) using in vivo and ex vivo imaging techniques. Methods: Five RBCD patients with penetrating keratoplasty (PK) were enrolled. Before surgery, all patients underwent a complete ophthalmological examination including slitlamp biomicroscopy, in vivo confocal microscopy (IVCM) and anterior segment (AS) optical coherence tomography (OCT). After PK, corneal buttons were examined by light and transmission electron microscopy (TEM). Correlations between in vivo and ex vivo images were analyzed. Results: In all cases, irregular geographic-like subepithelial gray-white opacities were observed in the central and mid-peripheral cornea. AS-OCT images of the cornea of all patients revealed hyperreflective homogeneous and continuous deposits concentrated at the level of Bowmans layer and anterior stroma. Using IVCM, a highly reflective irregular amorphous material was observed from intermediate epithelial cells to the anterior stroma. Sparse deposits of highly reflective material were also detected in the posterior stroma. TEM showed in all specimens basal epithelial cells containing small vesicles with rod-shaped dense material. Conclusions: IVCM and AS-OCT may be a useful adjunct to biomicroscopy for the diagnosis and management of RBCD. The correlations between the different in vivo and ex vivo imaging techniques emphasize the hypothesis of an epithelial origin for RBCD.

Porcine endothelial grafts could survive for a long term without using systemic immunosuppressors: An investigation of feasibility and efficacy of xeno-Descemet's stripping automated endothelial keratoplasty from WZS-pig to rhesus monkey

In current non‐human primate models, full‐thickness porcine grafts could not achieve long‐term survival without using potent systemic immunosuppressors. Moreover, the thickness disparity in xeno‐PKP proved to be hard to manipulate and may cause several complications which also could prevent the grafts from long survival. Considering the advantages of Descemets stripping automated endothelial keratoplasty (DSAEK) derived from its ultrathin graft and lower rejection rate, we hypothesize xeno‐DSAEK may overcome these imperfections in xeno‐PKP. The aim of this study was to explore the feasibility and efficacy of xeno‐DSAEK and to investigate the possibility of long‐term survival of porcine DSAEK grafts only using local immunosuppressors.

The feasibility and efficacy of preparing porcine Descemet’s membrane endothelial keratoplasty (DMEK) grafts by two techniques: An ex-vivo investigation for future xeno-DMEK

Descemet’s membrane endothelial keratoplasty (DMEK) might be a promising technique for future xeno‐corneal transplantation due to its ultrathin graft, extremely low rejection occurrence, suture‐free graft fixation, and minimal immunosuppressive regime usage. The aim of this study is to explore the feasibility and efficacy of preparing porcine DMEK grafts by 2 techniques and investigate the graft ultrastructure.

Labial Salivary Gland Transplantation for Severe Dry Eye in a Rhesus Monkey Model

Purpose To evaluate the effectiveness of autologous labial salivary gland with labial mucous membrane graft in a rhesus monkey model with severe dry eye. Methods Eight eyes of eight rhesus monkeys with severe dry eye were included. Four eyes underwent autologous labial salivary gland and mucous membrane graft (group 1) and four eyes served as controls (group 2). The ocular surface was evaluated before and after transplantation surgery (at 1, 4, 8, 12, and 24 weeks). Conjunctival impression cytology was performed before and 24 weeks after transplantation. Finally, a histological analysis of the cornea, conjunctiva, and transplanted grafts was performed. Results At inclusion (n = 8) the mean Schirmer test was 1.31 ± 0.53 mm, the mean fluorescein score was 4.7 ± 1.65, and the mean lissamine green staining was 4.38 ± 0.48. After transplantation, a significant increase in tear secretion was observed with the mean Schirmer test results in group 2 significantly higher than those observed for group 1 at all time points (P < 0.05). Similarly, fluorescein and lissamine green scores were significantly lower in group 2 than in group 1 at all time points after transplantation (P < 0.05). Impression cytology specimens showed severe conjunctival squamous metaplasia without goblet cells in both groups. Under light microscopy, no significant difference was observed between the cornea and the conjunctiva of the two groups. Conclusions Labial salivary gland transplantation provided a basal secretion of tears and improved ocular surface staining scores during the first 3 months in a severe rhesus monkey model of dry eye. However, this was not accompanied by major improvement of ocular surface tissues. Chinese Abstract.

Specific demographic factors could predict deceased potential cornea donors: A retrospective study from Beijing Tongren Hospital Eye Bank

Abstract Compared with evident cornea donors (ECDs), deceased potential cornea donors (DPCDs) have no obvious donor identifications to reference, which causes many eligible cornea tissues to be wasted. The demographic characteristics of DPCDs might be different from those of ECDs owing to the following different features: donation consent provided by relatives and willingness to donate before death. Thus, the aim of this study is to reveal the demographic characteristics of DPCDs by comparing DPCDs and ECDs. The demographic factors of 138 donors (both DPCDs and ECDs) were collected from the Beijing Tongren Hospital Eye Bank database and analyzed. To differentiate DPCDs from ECDs using the above-mentioned features, we interviewed the relatives of the donors by telephone. The relatives’ attitudes toward cornea donation and their suggestions for our donation service were also acquired during the interview. Two logistic regressions were performed to reveal the demographic factors influencing the 2 features and indicate DPCDs. The donors had certain demographic characteristics (elderly, secondary, or tertiary education level, central district resident), and the most frequent cause of death for the donors was a malignant tumor (n = 56, 43.1%). All the relatives had positive attitudes toward cornea donations, and they hoped to increase publicity efforts to encourage more people to donate and establish more convenient and efficient access for cornea donation. In univariate regressions, age (P = .004, >50 years: odds ratio [OR] = 6.89, 95% confidence interval [CI]: 1.82–26.05), marital status (P = .043, divorced: OR = 9.00,95% CI: 1.33–60.80) significantly influenced relative consent, whereas age (P = .001, >50 years: OR = 15.00, 95% CI: 3.00–74.98), and family address (P = .001, central district: OR = 1) were significant factors influencing the willingness to donate before death. In multivariate regression, age (P = .021, >50 years: OR = 8.14, 95% CI: 1.37–48.41) was the only significant factor influencing relative consent. Similarly, age (P = .02, >50 years: OR = 7.55, 95% CI: 1.21–47.25) was the only factor influencing willingness to donate before death. In conclusion, specific demographic factors could indicate DPCDs and might reveal directions and methods for cornea donation coordination in the future.

Effect of Ultraviolet Light Irradiation Combined with Riboflavin on Different Bacterial Pathogens from Ocular Surface Infection

In order to study Staphylococcus epidermis and Staphylococcus aureus in vitro viability after the exposure to ultraviolet (UV) light and riboflavin, twelve strains of Staphylococcus epidermis and twelve strains of Staphylococcus aureus were isolated from patients with bacterial keratitis. The growth situation of Staphylococcus epidermidis and Staphylococcus aureus under different experimental conditions was qualitatively observed. The number of colonies surviving bacteria was counted under different UV light power and different exposure time. The experiment showed that there was no inhibition effect on the growth of bacteria using riboflavin alone. In UV alone group and UV-riboflavin group, inhibition effect on the bacteria growth was found. The UV-riboflavin combination had better inhibition effect on bacteria than UV irradiation alone. The amount of bacteria in the UV-riboflavin group was decreased by 99.1%~99.5% and 54.8%~64.6% in the UV alone group, when the UV light power was 10.052 mW/cm2 and the irradiation time was 30 min. Moreover, with the increase of the UV power or irradiation time, the survival rates of bacteria were rapidly reduced. Compared with Staphylococcus aureus, Staphylococcus epidermis was more easily to be killed under the action of UV light combined with riboflavin.