Refractive surgery has entered the era of diversification. More and more advanced surgical equipment and materials, refined surgical skills and acceptance by the public have become a reality. How to make customized surgical decision and accurate surgical design is the current focus of concern, aiming to improve the safety, visual quality and satisfaction of laser refractive surgery and implantation of intraocular collamer lens. Laser corneal refractive surgery is still the most popular refractive surgery.

Objective To compare early visual outcomes of SmartPulse Technology (SPT)-assisted transepithelial photorefractive keratectomy (TPRK) or femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) with that of traditional TPRK/FS-LASIK. Methods This was a retrospective comparative study of two main groups, a surface surgery group and a stromal surgery group. The surface surgery group included two subgroups: an SPT-TPRK group consisting of 36 eyes of 19 patients and a TPRK group consisting of 40 eyes of 21 patients. All patients were followed up on the 3rd day, 10th day, 1st month and 3rd month after surgery and uncorrected visual acuity (UCVA) was measured and recorded. The stromal surgery group included two subgroups: an SPT-FS-LASIK group consisting of 49 eyes of 25 patients and a FS-LASIK group consisting of 48 eyes of 24 patients. All patients were followed up on the 1st day, 10th day, 1st month, and 3rd month after surgery, and UCVA was measured and recorded. Topography was performed before surgery and on the 1st month and 3rd month after surgery in all patients. Statistical analysis included repeated measures ANOVA, ?字２ test and independent t-test. Results There were no significant differences between the SPT-TPRK group and TPRK group in age, spherical equivalent, best corrected visual acuity or central corneal thickness before surgery, nor were there any significant differences between the SPT-FＳ-LASIK group and FＳ-LASIK group in the pre-operative examinations. There were no significant differences in post-operative UCVA between the TPRK and SPT-TPRK groups at any time point after surgery. However, there was a significant difference in UCVA between the SPT-FＳ-LASIK group and FＳ-LASIK group (F=12.067, P<0.01) on the 1st day and 10th day (P<0.05) after surgery with better acuity results in the SPT-FS-LASIK group. But there was no significant difference in post-operative visual outcomes between these two groups on the 1st and 3rd months. The surface regularity index (SRI) of the SPT-FS-LASIK group on the 1st month was significantly lower than that of the FS-LASIK group (t=2.95, P<0.01). Conclusion SPT-FS-LASIK tends to provide better UCVA than traditional FS-LASIK during the early days after surgery.

Objective   To observe the impact of preoperative anterior chamber depth (ACD) on anterior chamber angle morphology after phakic posterior chamber implantable collamer lens (PPC-ICL) implantation. Methods One hundred and thirty-two eyes of 80 consecutive patients with myopia undergoing PPC-ICL implantation were enrolled in this retrospective study. The patients were divided into three groups according to preoperative anterior chamber depth: group A: ACD＜3.0 mm; group B: 3.0≤ACD＜3.5 mm; group C: ACD≥3.5 mm. Before surgery and 3 months after surgery, anterior segment optical coherence tomography (AS-OCT) was used to measure anterior segment morphology. The indexes observed included ACD, angle opening distance (AOD500), trabecular-iris space area (TISA500) and scleral spur angle (SSA) in the 0° and 180° positions. Analysis of variance, correlation analysis and a paired t-test were used for statistical analysis. Results For all the patients, the measured values of preoperative AOD500 (0°, 180°) (r=0.51, 0.47), TISA500 (0°, 180°) (r=0.55, 0.52) and SSA (0°, 180°) (r=0.46, 0.58) were positively correlated with ACD (P＜0.01). Three months after surgery, the average ACD, AOD500, TISA500 and SSA values of the three groups had significantly decreased compared to preoperative values (P＜0.05). The measurements of AOD500 (F=7.00, 5.08), TISA500 (F=6.42, 3.06) and SSA (F=7.20, 4.73) in the 0° and 180° positions in group A were significantly lower than those in groups B and C (P＜0.05), and there was no significant difference between group B and group C. The postoperative AOD500, TISA500 and SSA in the three groups declined in the same proportion, and there were no statistically significant differences. The PPC-ICL vaults in groups A and B were lower than those in group C (F=5.37, P＜0.05). Three months after surgery, the changes (percentage) in AOD500 (r=0.54, 0.50), TISA500 (r=0.49, 0.48) and SSA (r=0.60, 0.61) were positively correlated with ICL vault (P＜0.01). No anterior chamber angle closure was found during the follow-up period, and there was no significant decrease in intraocular pressure in the three groups after surgery. Conclusion The morphology of the anterior chamber changes significantly after PPC-ICL implantation. Patients with a shallow anterior chamber will show a shallower anterior chamber depth and narrower anterior chamber angle after surgery. The change in anterior chamber morphology will be more obvious in patients with a higher vault.

Objective To compare vault and other biometric measurements obtained after Collamer lens (PPC-ICL) implantation using a Pentacam anterior segment system and an anterior segment optical coherence tomography system (AS-OCT). Methods In this cross-sectional study, vault and other biometric were was measured in 100 eyes of 50 patients after Collamer lens (PPC-ICL) implantation using a Pentacam and AS-OCT. The statisitical significance of the difference between the measurements was evaluated by a paired t-test and consistency was assessed by Bland-Altman analysis. Results The mean vault measured by Pentacam and AS-OCT was 353.8±124.0 µm and 536.2±150.8 µm (t=27.92, P<0.05) with a significant positive relationship (r=0.905, P＜0.05). There was a 95% level of consistent interval for the difference in interval width (54.3-310.5 µm). Conclusion The measurements obtaind by Pentacam was much lower than AS-OCT. The difference between the measurements of the vault obtained by the two instruments should be considered and accurately evaluated.

Objective To investigate the impact of BPV, the inhibitor of phosphatase and tensin homologue deleted on chromosome ten (PTEN), on lipopolysaccharide (LPS)-induced expression of inflammatory cytokines in rabbit corneal fibroblasts and to study its possible mechanism． Methods Ten healthy, mature New Zealand white rabbits bought in the Animal Lab Center of Tianjin Medical University were used in this experimental study. Primary cultures of rabbit corneal fibroblasts were isolated and cultured from corneal tissue explants in vitro． In the preliminary experiment, second-generation cells were divided into groups based on different doses of LPS (0.1, 1, 10 µg/ml) and BPV(250, 500, 1 000 nmol/L), and the survival rate of the cells was determined by MTT assay to determine proper concentrations. In the next stage of the experiment, corneal fibroblasts were randomly categorized into three groups based on different stimuli: a control group, LPS group and LPS+BPV group. The gene expression of inflammatory cytokines, for example, interleukelin-6 (IL-6) and interleukelin-8 (IL-8), were examined by real-time quantitative polymerase chain reaction (PCR). Expressions of associated proteins, like PTEN and phospho-AKT were evaluated by Western blot. ELISA was conducted to detect the levels of IL-6 and IL-8 in the supernatant of each group. Data were analyzed by ANOVA and an LSD-t test. Results The results of the MTT assay in the preliminary experiment showed that different doses of LPS and BPV could reduce the survival rate of cells and the differences were statistically significant (χ²=22.32, 17.82, P<0.01). After multiple comparisons among groups, 1 µg/ml LPS and 500 nmol/L BPV were chosen as the proper concentrations. The results of real-time PCR indicated that the relative expression levels of IL-6 mRNA and IL-8 mRNA in all groups showed significant differences (F=46.65, 42.59, P<0.01). And IL-6 mRNA and IL-8 mRNA in the LPS group were 1.29±0.19 and 1.11±0.04, which were significantly higher than expression levels in the control group (P＜0.01), but much lower than 1.17±0.08 and 0.92±0.15 in the LPS+BPV group (P＜0.01). Western blot analysis showed that the relative expression of PTEN in the BPV group was significantly lower than expression in the control group (t=29.39, P<0.01). The relative expression levels of phospho-AKT in all groups showed statistically significant differences (F=62.83, P<0.01). And the relative expression of phospho-AKT in the LPS+BPV group was 0.82±0.07, which was significantly higher than 0.63±0.05 in the LPS group. All differences were statistically significant (P<0.01). The results of ELISA indicated that the relative mRNA expression levels of IL-6 and IL-8 in all groups were statistically different (F=32.41, 27.13, P<0.01). The relative expression levels of IL-6 and IL-8 in the supernatant of the LPS group were significantly higher than those in the control group (P＜0.01) but much lower than levels in the LPS+BPV group (P＜0.01). Conclusion BPV, the inhibitor of PTEN, may decrease LPS-induced gene expression and release of IL-6 and IL-8, inhibiting the inflammation reaction in rabbit corneal fibroblasts. The PI3K/AKT signal pathway may be involved in the process.

Objective To assess retinal vessel caliber using computer-assisted software; to study clinical reliability and consistency between different reasearchers. Methods In this cross-sectional study, the retinal vessel diameters of 100 fundus pictures of children aged from 4 to 8 years were measured independently by 4 researchers using IVAN (University of Wisconsin, Madison, WI) computer-assisted quantitative assessment software. The arteriolar/venular caliber was measured and the ratio was calculated with the semi-automated software. Intraclass correlation coeffient were calculated to assess agreement between different researchers. Kappa test analysis was performed to assess agreement between new researchers and skilled researcher. Bland-Altman plots were drawed. Results Analysis of the retinal arteriolar and venular can be performed and reproduced on routine retinal photographs. The mean central retinal arteriolar (CRAE) measurements by the 4 researchers were 121.14±17.03, 120.40±17.68, 120.45±17.61, 120.79±19.05; the ICC value was 0.943(0.923-0.960). The mean central retinal venular equivalents (CRVE) were 181.66±29.33, 181.55±29.31, 181.23±30.12, 181.53±31.46; the ICC value was 0.939(0.917-0.956). The mean arteriolar/venular measurements were 0.67±0.06, 0.66±0.07, 0.67±0.06, 0.67±0.06; the ICC was 0.685(0.625-0.715). The Kappa values of CRAE were 0.702, 0.745 and 0.744, respectively; the values of CRVE were 0.822, 0.860 and 0.860, respectively; the values of the arteriolar/venular were 0.753, 0.604 and 0.601. Conclusion Retinal vessel measurements with IVAN software are reliable early in life. It can be helpful for future retinal vessel caliber assessment from a young age.

Objective To investigate the factors that influence postoperative refractive error using the SRK/T and optimized Haigis formulas for eyes with high myopia, and to compare the accuracy of the two formulas. Methods This was a retrospective study. Thirty-eight patients (63 eyes) with axial lengths of ≥26 mm underwent cataract surgery from July 2011 to March 2015 in the Eye Hospital of Wenzhou Medical University. Axial length (AL), corneal curvature (K) and preoperative anterior chamber depth (AC) were measured by IOL-Master preoperatively. The SRK/T and optimized Haigis formulas were used to determine the intraocular lens (IOL) power and monofocal foldable IOLs were then implanted during surgery. Refractions were measured with a phoropter three months postoperatively. A paired t test was used to analyze the difference in refractive error measurements calculated by the two formulas. The difference in the proportion of hyperopia migration was analyzed by a McNemar test while the difference in the distribution of absolute error (AE) was analyzed by a Wilcoxon signed-rank test. The correlation of the difference in target refractions between the two formulas, as well as AE, AL, corneal curvature and preoperative anterior chamber depth were analyzed by a Pearson correlation analysis. Multiple linear regression was used to investigate the relative factors in refractive error based on the two formulas. Results Refractive errors calculated by the SRK/T and optimized Haigis formulas were -0.52±0.79 D and -0.67±0.79 D, respectively, with ratios of a hyperopic migration of 78% and 86%, respectively. The difference in target refraction between the two formulas was negatively correlated with AL (r=-0.27, P<0.05), and positively correlated with K (r=0.73, P<0.01). Both AEs were positively correlated with axial length (SRK/T: r=0.43, P<0.01; optimized Haigis: r=0.31, P<0.05). Anterior chamber depth was grouped into AC≤3.5 mm and AC>3.5 mm. In the group with AC≤3.5 mm, linear regression formulas for refractive errors calculated with the SRK/T and optimized Haigis formula were ■=3.74-0.15AL (R2=0.27, F=3.88, P<0.05) and ■=12.03-0.19K-0.13AL (R2=0.27, F=3.73, P<0.05). In the group with AC>3.5 mm, linear regression formulas for refractive errors with the SRK/T and optimized Haigis formula were ■=1.40AC-0.37AL (R2=0.62, F=13.40, P<0.01) and ■=14.02+1.76AC-0.25K-0.35AL (R2=0.62, F=13.59, P<0.01). Conclusion For eyes with a long axial length, the optimized Haigis formula is better than the SRK/T formula because postoperative refractive error exhibits a more obvious hyperopic shift using the SRK/T formula. With regard to a steep K value, refractive error increases as K augments using the optimized Haigis formula. Thus the SRK/T formula is the better choice under this condition. When preoperative anterior chamber depth is more than 3.5 mm, the target myopic refraction can be reduced with either formula.

Objective To study the clinical characteristics, pathogens, and treatment of graft fungal infection after corneal transplantation. Methods Twenty-nine patients (34 eyes) who were diagnosed with a graft fungal infection after keratoplasty in Qingdao Eye Hospital, Shandong Eye Institute, from October 2005 to January 2016, were reviewed. Twenty-five male (86%) and 4 female patients (14%) were included in the retrospective, interventional case series study. Data for primary diseases before keratoplasty, onset time of graft fungal infection, risk factors, clinical characteristics, pathogens, and treatments were analyzed. The data were analyzed with a signed-rank test. Results Penetrating keratoplasty was performed on 25 patients(74%) and lamellar keratoplasty was performed on 9 patients (26%). The most common primary disease before keratoplasty was infectious keratitis (24 cases, 70%). The average interval between keratoplasty and graft fungal infection was 39.5±43.0 months (1-144 months). The grafts were infected by fungi within 6 months in 9 cases (26%) and within 6 months to one year in 3 cases (9%) postoperatively. Fungal infection occurred during September-November in 17 cases (50%). Fungi were positively cultured in 27 cases (79%), and the main pathogens were fusarium (9 cases, 33%) and alternaria (6 cases, 22%). Infected lesions were located only on the corneal grafts in 29 cases (85%) and host corneas were involved in five cases (15%). Central or paracentral corneal ulcers were observed in 22 cases (65%), including large ulcers (length ＞4 mm) in 15 cases and small ulcers (length ≤4 mm) in 7 cases; and peripheral ulcers not bigger than 4 mm in length were seen in 12 cases. Twenty-seven cases selected drug therapy combined with surgical treatment, 4 cases chose simple drug therapy, and the other 3 cases (9%) declined surgeries and asked to be discharged from our hospital. The most common surgical scherne is keratoplasty (59%), followed by evisceration or enucleation (22%). Conclusion Infectious keratitis dominates the primary disease of corneal graft fungal infections, and most of them occurred in the autumn. Fusarium and alternaria are the main pathogens. Timely diagnosis and treatment can minimize the impact of graft fungal infections on patient vision.

Myopia is one of the most prevalent eye diseases that affect vision of young adults in Asia. Cornea refractive surgery is the main choice for myopic patients to remove glasses and improve life quality. As the development of technologies, refractive surgery become more diverse, and the demands of patients for post-surgery visual quality become higher. How to choose the most suitable refractive surgery to achieve best results is the question that every refractive surgeon faces. This paper provides a brief review on the customized methods selection, parameter setting and ablation pattern for refractive surgery.