[Advances of tight junction damage in the corneal epithelial barrier in the pathogenesis of corneal diseases].

The cornea is a transparent tissue with significant refractive and barrier functions. Corneal epithelium constitutes the first line of defense against foreign pathogens. Corneal epithelial cells interact to form a functionally selective permeability barrier. Dysfunction of this barrier leads to corneal impairment followed by a series of ocular surface diseases and even blindness. Tight junctions (TJ), located at the top of the intercellular space of corneal epithelial superficial cells, play a critical role in establishing and maintaining the barrier function. Previous studies have shown that destruction of the TJ acts as a crucial step of the occurrence and progression of multiple ocular surface diseases. Understanding the fundamental features and functions of the TJ, noticing the risk factors of TJ disruption, and clarifying the key role of TJ in the pathogenesis of various ocular surface diseases will help to better understand and treat ocular surface diseases.

[Research advances in contact lens-associated dry eye].

Dry eye is the most common disease in ophthalmic clinics besides refractive error, which seriously affects the life quality of patients and has become an important public health problem in China. Dry eye as a kind of multifactorial disease can be induced or accelerated by contact lens wear, which is considered as one of the risk factors of dry eye. Studies have shown that the incidence of dry eye is higher in contact lens wearers than in normal people. In 2017, the Tear Film and Ocular Surface Society included contact lens-associated dry eye (CLADE) in the iatrogenic dry eye for the first time, and its importance is evident. However, ophthalmologists mostly used to focus on serious complications such as keratitis caused by contact lens wear, and CLADE has not been well valued and understood. This article reviews the latest studies on the epidemiology, pathogenesis, diagnosis, prevention, and treatment of CLADE.

[Research advances of morphological changes of the choroid in high myopia].

Choroidal thinning is an important feature of high myopia and has a negative correlation with the degree of myopia. However, due to the limitations of choroidal imaging, specific changes in choroidal thickness and vasculature are unclear. In recent years, the development of optical coherence tomography technology and optical coherence tomography angiography technology has made it possible to solve the problem. Emergence of biomarkers that objectively quantify choroidal thickness and vascular changes will help us understand the pathogenesis of high myopia and provide new ideas for the prognosis and treatment of myopia. In this review, in order to provide reference for clinical work, we summarize recent advances in the application of the two technologies in observing morphological changes of the choroid in high myopia and discuss the problems and prospects when they are combined with artificial intelligence for choroidal imaging. (Chin J Ophthalmol, 2021, 57: 459-464).

[The rotational stability of Toric intraocular lenses and influencing factors in cataract patients with different axial length].

Objective: To evaluate the rotational stability of the Toric intraocular lens (TIOL) and influencing factors in cataract patients with different axial length. Methods: This retrospective cohort study consecutively enrolled patients who had phacoemulsification and AcrySof TIOL implantation in Peking University Third Hospital from May 2018 to January 2019. Based on axial length, patients were divided into two groups. Group A consisted of patients whose axial length was ≤ 24 mm. Patients whose axial length was >24 mm were included in group B. Data at three months postoperatively were used to evaluate the rotational stability of TIOL and its correlation with axial length, corneal white to white distance, lens thickness and TIOL spherical power. And t test, nonparametric test, chi-square test and Spearman test were used for statistical analysis. Results: Group A enrolled 39 patients (17 males and 22 females), with a median age of 74 years (range, 36-86 years). Group B enrolled 26 patients (11 males and 15 females), with a median age of 68 years (range, 36-86 years). For the efficacy of TIOL, in group A, the best corrected distance visual acuity (BCDVA, logarithm of the minimum angle of resolution) was 0.30 (0.10, 1.00) preoperatively and 0.10 (0.00, 0.60) postoperatively, and the astigmatism was 2.11 (0.95, 5.10) D preoperatively and 1.00 (0.00, 1.75) D postoperatively. In group B, the BCDVA was 0.36 (0.05, 1.00) preoperatively and 0.05 (0.00, 0.40) postoperatively, and the astigmatism was 2.00 (0.78, 3.76) D preoperatively and 0.75 (0.00, 2.25) D postoperatively. Between group A and group B, there were no significant differences in BCDVA (P=0.604) and astigmatism (P=0.789) preoperatively.In these two groups, postoperative BCDVA and astigmatism both significantly improved compared to preoperative parameters (both P<0.01). Between group A and group B, there were no significant differences in BCDVA (P=0.536) and astigmatism (P=0.076) postoperatively. In terms of rotational stability, the rotation in group A was 5.15°±3.62°, and that in group B was 6.50°±4.66°. There was no statistical difference between two groups (P=0.195). As for predictability, the percentage of eyes with rotation ≤5° was 59.0% (23 eyes) in group A and 50.0% (13 eyes) in group B. There was no statistical difference between the two groups (P=0.647). There was no significant correlation between the rotational stability of TIOL and axial length, corneal white to white distance, lens thickness or TIOL spherical power (P=0.836, 0.568, 0.170, 0.365). Conclusions: The rotational stability of TIOL at three months postoperatively in patients whose axial length >24 mm is of no difference with patients whose axial length ≤ 24 mm. It has no correlation with axial length, corneal white to white distance, lens thickness and TIOL spherical power. (Chin J Ophthalmol, 2020, 56: 41-46).