Any kind of surgery method has the risk of the corresponding surgical complications,so is eye surgery.Recent years,cataract surgery technology is being constantly progress and develop,but the complications related to these surgical techniques exist in clinic comprehensively.Recognizing the updated clinical problems associated with each different technique should be necessary and helpful to the available clinical application of new technique,which will enhance the good results of the development of cataract surgery and improve the visual quality of patients.Meanwhile,the experience of understanding and preventing the techinique-related-complications would promote the novel technology of cataract surgery and the innovation of the medical equipment.It is important for us to attach importance to the complications associated with the development of cataract surgery technique.

Objective: To evaluate the relationship between preoperative nystagmus and visual outcome of congenital cataract surgery. Methods: Retrospective review of 81 patients (84 eyes) who underwent surgery for cataract was conducted,in which 7 cases of unilateral cataract and 3 of bilateral cataract were associated with preoperative nystagmus. All patients lacked other structural ocular defects or neurologic abnormalities and were old enough to cooperate with recognition visual acuity testing. Outcome parameters studied were best-corrected postoperative visual acuity of the eyes. Results: Best corrected postoperative visual acuity of the nystagmus eyes was 0.05 or worse in 3(23%,3/13), between 0.05 and 0.3 in 9(69%,9/13),and 0.3 or better in 1(8%,1/13).Best corrected visual acuity of the eyes without nystagmus was 0.05 or worse in 6(8%),between 0.05 and 0.3 in 24(34%),and 0.3 or better in 41 ((58%).) There was a statistical significance of preoperative visual acuity compared to postoperative visual acuity in cataract with(P=0.04) or without nystagmus. The great statistical significance was shown in the improvement of visual acuity between the patients with nystagmus and without nystagmus. Conclusion: Preoperative nystagmus in children with cataract does not preclude visual improvement, but may predict a poorer visual acuity outcome after cataract surgery. In these patients a decision must be made as to whether or not surgical intervention for the cataract would be worthwhile at this stage.

Background Idiopathic macular epiretinal membrane (IMEM) combined with age-related cataract (ARC)is a common eye disease and the primary managing approach is the combination of phacoemulsification,intraocular lens (IOL) implantation and vitrectomy.However,whether the ocular length measured by IOL Master is accurate for the calculation of IOL refraction in the eye with IMEM remains unclear.Objective The aim of this study was to evaluate the refractive outcomes of combination surgery of phacoemulsification,IOL implantation and vitrectomy in IMEM eyes.Methods A prospective cohort study was designed.Forty-two eyes of 42 patients with IMEM combined with ARC (IMEM+ARC group) were enrolled in Peking University People's Hospital and the combination of phacoemulsification,IOL implantation and vitrectomy was performed from September 2010 to August 2011,and 47 eyes of 47 patients with ARC were included for the phacoemulsification combined with IOL implantation in the corresponding period (ARC group) under the approval of Ethic Committee of Peking University People's Hospital and informed consent of the patients.Ocular length and corneal curvature were measured using IOL Master,and the expected IOL diopter was calculated with SRK-T formula.Regular eye examination and medical optometry were performed 1 month and 3 months after operation to obtain the actual diopter and the refractive error.The outcomes were compared between the two groups.The correlations of refractive error with change of fovea thickness were evaluated after operation in the IMEM+ARC group.Results There were no statistically significant differences in the age,ocular length and corneal curvature between the two groups before operation (P =0.863,0.704,0.770).The visual acuity was improved 3 months after operation in comparison with before operation in both groups (P=0.001,0.000).The negative diopters were obviously higher 1 month and 3 months after operation than those before operation in both groups (all at P＜0.001),but no significant difference was seen between the IMEM+ ARC group and ARC group (Fgroup =0.417,P =0.520).The diopter deviations 1 month and 3 months after operation were (-0.727±0.666)D and (-0.628±0.627)D in the IMEM+ARC group,and those in the ARC group were (-0.664±0.644) D and (-0.642±0.550) D,showing insignificant differences between the two groups (Fgroup =0.036,P =0.849 ; Ftime =1.523,P =0.221).In IMEM + ARC group,the macular fovea thickness was (474.89 ± 135.76)μm in preoperation,and the shift values of macular fovea thickness were (-83.84 ±91.12)μm and (-158.53±113.03) μm in postoperative 1 month and 3 months.No positive correlations were presented between the diopter deviations and change of fovea thickness 1 month and 3 months after operation in the IMEM+ARC group (r=0.200,P =0.229 ; r =0.065,P =0.698).Conclusions Myopia shift after operation is similar in the IMEM combined with ARC patients to the only ARC patients,suggesting that the ocular length and corneal curvature measured by IOL Master is not affected by epiretinal membrane.

Background Bilateral congenital cataract is one of the vision-threating diseases during infant age.Intraocular lens (IOL) implantation is an ideal refraction correction method for children who have already received bilateral cataract extraction.However,the timing and effectiveness of secondary IOL implantation are still under debate.Objective This study was to analyze the visual changes and affecting factors before and after secondary IOL implantation and explore the operative timing.Methods The clinical data of 58 eyes of 29 patients who received bilateral cataract extraction-refractive correction and vision training-secondary IOL implantation in Peking University People's Hospital from January 2012 to December 2014 were retrospectively analyzed.All the patients received bilateral cataract extraction and posterior capsulotomy with anterior vitrectomy during their first year of life firstly,followed by the wearing of refractive spectacles or visual training,and secondary IOL implantation was simultaneously performed until ＞2 years old.Best corrected visual acurity (BCVA) (LogMAR) was examined at 1 week before and 3 months after secondary surgery under the mydriasis.Changes,distribution alternation of BCVA and the relationship of visual prognosis with preoperative visual acuity were evaluated.Results The average age at surgery of the patients was (3.26±2.07) months and that at secondary IOL implantation was (4.79± 1.38) years,with the operative interval of (4.28± 1.33) years.The BCVA before and after secondary IOL implantation was 0.790± 0.422 and 0.570±0.307 respectively,showing a significant difference between them (t =3.223,P＜0.001).The number of eyes with BCVA ≥ 0.5 after surgery was significantly more than that before surgery (x2=53.931,P＜0.001).A positive correlation in unilateral BCVA was seen between before and after secondary IOL implantation (R2 =0.232,F =17.037,P ＜ 0.001).Conclusions A systemic management of bilateral cataract extractionrefractive correction and vision training-secondary IOL implantation for congenital cataract is beneficial to BCVA improvement and amblyopia treatment,and it should be performed as early as possible on the premise of ensuring the safety of life.Secondary IOL implantation should be timely carried out for aphakic children with poor compliance and outcomes during vision training after congenital cataract extraction.

Despite the continuous improvement and development of modern cataract surgery technology, posterior capsule opacification (PCO) is still the common long-term complication causing secondary visual acuity decline after cataract surgery.Previous studies have shown that the occurrence of PCO is closely related to the proliferation, migration, epithelial-mesenchymal transition (EMT) and myofibroblast fibrosis of lens epithelial cells in the anterior capsule and lens equator.In terms of pathogenesis, recent research focuses on the role of cytokines, especially various growth factors.Vascular endothelial growth factor (VEGF) is a kind of growth factor that can promote vascular endothelial cell proliferation and migration, extracellular matrix degeneration and angiogenesis.In addition, there is increasing evidence showing that VEGF plays an important role in fibrosis, inflammation, neuroprotection and other aspects.In recent years, VEGF has been found to promote PCO formation directly or cooperatively with transforming growth factor-β2.Based on the function of VEGF and the relationship between VEGF and EMT, this paper mainly reviewed the advances in the role of VEGF in the eye and the pathogenesis of posterior capsule opacification.

Objective:To explore the application of artificial intelligence (AI) assistant system combined with case-based learning (CBL) in the teaching of strabismus specialty for ophthalmic residents.Methods:Forty ophthalmic residents who were trained in the Department of Ophthalmology of the People's Hospital of Peking University from January 2020 to December 2021 were divided into control group and experimental group, with 20 people in each group. The control group used the traditional teaching mode, and the experimental group used AI assistant system combined with CBL teaching. At the end of specialized training, the two groups were assessed for theoretical knowledge, clinical skills, clinical thinking and questionnaire survey, and the teaching effect was evaluated. SPSS 26.0 was used for Chi-square test, one-way ANOVA and independent-samples t-test. Results:The scores of theoretical knowledge [(34.10±1.33) points], clinical skills [(24.75±1.02) points] and clinical thinking [(24.80±0.77) points] in the experimental group were significantly higher than those in the control group [(33.15±1.35) points, t=2.24, P=0.031; (23.60±0.82) points, t=3.93, P<0.001; (24.20±0.83) points, t=2.37, P=0.023]. For the evaluation of teaching effect, the experimental group improved the learning interest ( t=11.47, P<0.001), clinical thinking ability ( t=9.36, P<0.001), knowledge and skill level ( t = 17.71, P < 0.001), knowledge sharing ( t=31.17, P< 0.001) and overall satisfaction ( t=10.60, P<0.001), and these 5 aspects were scored higher in experimental group compared with the control group. Conclusion:The teaching mode combining AI assistant system and CBL teaching can improve the independent diagnosis and treatment ability of ophthalmic residents for strabismus diseases, establish a correct clinical thinking path, and obtain a better teaching effect than the traditional teaching mode.