Ocular surface system alterations in ocular graft-versus-host disease: all the pieces of the complex puzzle

Traditional Chinese medicine Xiaosheng Powder for dry eye disease: A protocol for systematic review and meta analysis

BACKGROUND

Dry eye disease (DED) has shown a significant increase in recent years, which seriously affects people's work and life. Xiaosheng Powder, a traditional Chinese medicine decoction, has been widely used in treating DED. However, there is no systematic review of the results of the study on this therapeutic effect. The purpose of this review is to evaluate the effectiveness and safety of Xiaosheng Powder in the treatment of DED.

METHODS AND ANALYSIS

The electronic databases to be searched will include MEDLINE (PubMed), Cochrane Central Register of Controlled Trials in the Cochrane Library, Excerpta Medica Database, China National Knowledge Infrastructure, China Scientific Journal Database, Wanfang Database and Chinese Biomedical Literature Database. Papers in English or Chinese published from inception to 2020 will be included without any restrictions. Improvement in Ocular Surface Disease Index will be assessed as the primary outcomes. Tear break-up time, Schirmer I test, fluorescent, adverse events, and the recurrence rate after at least 3 months of the treatment will be evaluated as secondary outcomes. We will conduct a meta-analysis of randomized controlled trial if possible. The methodological qualities, including the risk of bias, will be evaluated using the Cochrane risk of bias assessment tool, while confidence in the cumulative evidence will be evaluated using the Grading of Recommendations Assessment, Development, and Evaluation approach.

ETHICS AND DISSEMINATION

It is not necessary for a formal ethical approval because the data is not individualized. The results of this review will offer implications for the use of Xiaosheng Powder as a treatment for DED. This knowledge will inform recommendations by ophthalmologist and researchers who are interested in the treatment of DED. The findings of this systematic review will be disseminated through peer-reviewed publications and conference presentations.

TRAIL REGISTRATION NUMBER

PROSPERO CRD42020147709.

Longitudinal Corneal Endothelial Cell Changes in Patients Undergoing Hematopoietic Stem Cell Transplantation

PURPOSE

To evaluate longitudinally corneal endothelial cell changes in patients undergoing hematopoietic stem cell transplantation (HSCT) and to further investigate possible correlations with hematological and ocular characteristics.

METHODS

Prospective observational study conducted at a single center. All patients underwent a comprehensive ophthalmological examination, before and after HSCT, including slitlamp examination, Schirmer test, tear breakup time, ocular surface staining, specular microscopy of corneal endothelium, and Ocular Surface Disease Index questionnaire.

RESULTS

Twenty-five patients undergoing HSCT and 25 age- and sex-matched controls were included. At baseline, hematological patients showed significantly lower values of endothelial cell density (ECD) compared with those of controls (2514.5 ± 390.2 vs. 2723.7 ± 298.0 cells/mm, P = 0.038). After HSCT, ocular surface disease index score significantly increased (P = 0.020) and tear breakup time significantly decreased (P = 0.036). Conversely, no significant changes were found in Schirmer test and corneal fluorescein staining (always P > 0.05). Eight patients (32%) developed ocular graft-versus-host disease (GVHD). ECD values significantly decreased after HSCT (from 2514.5 ± 390.2 to 2409.5 ± 330.9 cells/mm, P = 0.009). The decrease in ECD values after HSCT was more pronounced in patients with ocular GVHD compared with those without (231.1 ± 188.8 vs. 45.6 ± 156.5, P = 0.016). No significant correlations between the changes in ECD and hematological and ocular characteristics were found (always P > 0.05).

CONCLUSIONS

Hematological patients showed a lower endothelial cell count already before HSCT, compared with controls. After HSCT, the endothelial cell count further significantly decreased, particularly in patients who developed ocular GVHD.

In Vivo Confocal Microscopy Morphometric Analysis of Meibomian Glands in Patients With Graves Ophthalmopathy

PURPOSE

To characterize meibomian glands (MGs) features in patients with Graves ophthalmopathy (GO) by in vivo confocal microscopy (IVCM) and to further investigate possible correlations with ocular surface characteristics.

METHODS

Consecutive patients with GO and controls were enrolled. The following ocular surface parameters were measured: tear break-up time, Schirmer test, and corneal fluorescein staining (Oxford score) were performed on each subject. IVCM of MGs was performed, and the scans were analyzed with ImageJ software for the calculation of the following: acinar unit density, total gland area, total lumen area (TLA), acinar longest diameter, and acinar shortest diameter. A nonparametric Mann-Whitney U test was used to compare variables between patients with GO and controls. The Spearman correlation analysis was used to evaluate the correlations between ocular surface and IVCM parameters.

RESULTS

Twenty-one patients with GO and 24 sex- and age-matched healthy controls were included. Acinar unit density was significantly lower in patients with GO compared with controls (24.5 ± 8.1 vs. 34.2 ± 7.5 U/mm; P < 0.001). In addition, patients with GO showed significantly higher values of TLA, acinar longest diameter, and acinar shortest diameter compared with controls (respectively, 3104.7 ± 1713.3 vs. 1393.8 ± 448.0 μm, 94.4 ± 21.2 vs. 64.3 ± 10.1 µm and 56.6 ± 15.3 vs. 42.2 ± 12.3 μm; always P < 0.05). In patients with GO, TLA showed a significant inverse correlation with Schirmer test (Rs = -0.467; P = 0.038).

CONCLUSIONS

IVCM allowed to detect distinctive features of MGs in patients with GO and could represent a surrogate tool for the assessment of MG status in these patients.

False Myths versus Medical Facts: Ten Common Misconceptions Related to Dry Eye Disease

Since the first definition of dry eye, rapid progress has been made in this field over the past decades that has guided profound changes in the definition, classification, diagnosis and management of the disease. Although dry eye is one of the most frequently encountered ocular conditions, various “old” misconceptions persist, in particular among comprehensive ophthalmologists not specialized in ocular surface diseases. These misconceptions hamper the correct diagnosis and the proper management of dry eye in the routine clinical practice. In the present review, we described the 10 most common misconceptions related to dry eye and provided an evidence-based guide for reconsidering them using the format “false myth versus medical fact”. These misconceptions concern the dry eye definition and classification (#1, #2, #3), disease physiopathology (#4), diagnosis (#5), symptoms (#6, #7) and treatment (#8, #9, #10). Nowadays, dry eye is still an under-recognized and evolving disease that poses significant clinical challenges to ophthalmologists. The two major reasons behind these challenges include the heterogeneity of the conditions that fall under the umbrella term of dry eye and the common discrepancy between signs and symptoms.

Clinical Applications of Astaxanthin in the Treatment of Ocular Diseases: Emerging Insights

Astaxanthin is a naturally occurring red carotenoid pigment belonging to the family of xanthophylls, and is typically found in marine environments, especially in microalgae and seafood such as salmonids, shrimps and lobsters. Due to its unique molecular structure, astaxanthin features some important biologic properties, mostly represented by strong antioxidant, anti-inflammatory and antiapoptotic activities. A growing body of evidence suggests that astaxanthin is efficacious in the prevention and treatment of several ocular diseases, ranging from the anterior to the posterior pole of the eye. Therefore, the present review aimed at providing a comprehensive evaluation of current clinical applications of astaxanthin in the management of ocular diseases. The efficacy of this carotenoid in the setting of retinal diseases, ocular surface disorders, uveitis, cataract and asthenopia is reported in numerous animal and human studies, which highlight its ability of modulating several metabolic pathways, subsequently restoring the cellular homeostatic balance. To maximize its multitarget therapeutic effects, further long-term clinical trials are warranted in order to define appropriate dosage, route of administration and exact composition of the final product.

The Role of Nutrition and Nutritional Supplements in Ocular Surface Diseases

Dry eye disease (DED) is a multifactorial disease of the ocular surface system whose chore mechanisms are tear film instability, inflammation, tear hyperosmolarity and epithelial damage. In recent years, novel therapies specifically targeting inflammation and oxidative stress are being investigated and used in this field. Therefore, an increasing body of evidence supporting the possible role of different micronutrients and nutraceutical products for the treatment of ocular surface diseases is now available. In the present review, we analyzed in detail the effects on ocular surface of omega-3 fatty acids, vitamins A, B12, C, D, selenium, curcumin and flavonoids. Among these, the efficacy of omega-3 fatty acid supplementation in ameliorating DED signs and symptoms is supported by robust scientific evidence. Further long-term clinical trials are warranted to confirm the safety and efficacy of the supplementation of the other micronutrients and nutraceuticals.