The risk factors of the progression of rhegmatogenous retinal detachment on patients with the fourteen-day quarantine in the early period of COVID-19 outbreak.

BACKGROUNDS: The COVID-19 Pandemic has a great impact on hospitals and patients. The 14-day quarantine caused surgery of rhegmatogenous retinal detachment (RRD) postponed. We aimed to explore the risk factors of RRD progression in a group of patients whose surgery was postponed during the top-level emergency response of COVID-19. METHODS: A retrospective case series. Medical records of all consecutive patients with a diagnosis of RRD who underwent a surgical treatment at Beijing Tongren Hospital's retina service from February 16, 2020, to April 30, 2020 have been reviewed retrospectively. Medical history, symptoms, and clinical signs of progression of RRD were recorded. RRD progression was defined as the presence of either choroidal detachment or proliferative vitreoretinopathy (PVR) progression during the quarantine period. Risk factors were analyzed using the Cox proportional hazards model, survival analysis, and logistic regression. RESULTS: Seventy-nine eyes of 79 patients met the inclusion criteria and were included in the study. The median time from the patients' presentation at the clinic to admission for surgery was 14 days (3-61 days). There were 70 cases (88.6%) who did not present to the hospital within 1 week of the onset of visual symptoms. There were 69 (87.3%) macular-off cases at the presentation and 27 (34.2%) cases combined with choroidal detachment. There were 49 (62.0%) cases with PVR B, 22 (27.8%) cases with PVR C, 4 (5.1%) cases with PVR D, and 4 (5.1%) cases with anterior PVR. After the 14-day quarantine, 21 (26.6%) cases showed RRD progression, and 9 cases showed RRD regression at the time of surgery. Neither the time of onset of the visual symptom (p = 0.46) nor the time between presentation and admission (p = 0.31) was significantly different between the patients with RRD progression and patients without RRD progression. The combination of choroidal detachment (3.07, 1.68-5.60, p<0.001) and retinal breaks located posterior to the equator (3.79, 1.21-11.80, p=0.02) were factors related to the progression of RRD. CONCLUSIONS: In our study during the COVID-19 outbreak, the RRD progression risk factors included a combination of choroidal detachment and retinal breaks posterior to the equator. Ophthalmologists should schedule the surgeries for RRD patients with these signs as soon as possible.

Association between dietary antioxidants and risk for diabetic retinopathy in a Chinese population.

BACKGROUND: Diabetic retinopathy (DR) is related to oxidative stress and insufficient intake of dietary antioxidants may be associated with the onset and progression of DR. This study aimed to detect the association between main dietary antioxidants intake and the risk for DR. METHODS: This is a cross-sectional study of a Chinese urban population. Four hundred and fifty-five subjects with type 2 diabetes were recruited and divided into diabetic patients without retinopathy (DWR) group and DR group based on their retinal status. CSMO (clinically significant macular oedema) was diagnosed by stereoscopic photography. Demographic and lifestyle characteristics were ascertained by questionnaire. General physical and ophthalmic examinations were completed for all subjects. Dietary antioxidants were assessed by 3-day food records. Subjects who have taken any type of vitamin supplements were excluded from the study. The association of dietary antioxidants with the risk for DR was analysed by logistic regression with adjustment of other factors. The dietary antioxidants levels of the CSMO subjects and non-CSMO subjects were compared using the Wilcoxon rank sum test. RESULTS: One hundred and nineteen subjects in DR group and 336 subjects in DWR group participated in the study. Only ten DR subjects had CSMO. The results showed that higher vitamin E (OR (95% CI):0.97 (0.95, 1.00), P = 0.036) and selenium (OR (95% CI):0.98 (0.96, 1.00), P = 0.017) intake appear to be the protective factors of DR. The dietary antioxidants levels of CSMO and non-CSMO subjects had no statistical differences (P > 0.05). CONCLUSIONS: Dietary antioxidants intake, particularly vitamin E and selenium, were observed to have protective effects on DR.

Association of candidate gene polymorphisms with diabetic retinopathy in Chinese patients with type 2 diabetes.

AIM: To investigate the association between a set of six candidate genes and the risk of diabetic retinopathy (DR) in an urban community cohort of Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: A population-based cross-sectional study. The diabetic subjects were recruited from an urban community in Beijing and categorized into groups of proliferative diabetic retinopathy (PDR), non-proliferative diabetic retinopathy (NPDR), or diabetic without any retinopathy (DWR) based on the fundus photography and duration of diabetes. Six candidate genes, including advanced glycation end product specific receptor (AGER), aldose reductase (AKR1B1), inducible nitric oxide synthase (iNOS), pigment epithelium derived factor (PEDF), tumor necrosis factor-alpha (TNF-α), and paraoxonase 1 (PON1), were chosen based on Meta-analysis of genetic association studies for DR and biochemical pathways implicated in DR progression. The allele and genotype distribution of 21 functional single-nucleotide polymorphisms (SNPs) in those 6 candidate genes were investigated using MassARRAY genotyping system. RESULTS: Among 1461 diabetic patients recruited from community, 569 were selected in following genotyping analysis, including 97 patients with PDR, 217 with NPDR, and 255 with DWR. For the promoter variant rs1051993 in AGER gene, the distribution of allele and genotype in PDR group differed from that in DWR group (allele: P=0.011; genotype: P=0.01). Compared with DWR, patients with PDR had lower frequencies of heterozygous genotype GT (9.8% for DWR, 1% for PDR, OR: 0.10, 95%CI: 0.01-0.72) and minor allele T (4.9% for DWR, 0.5% for PDR, OR: 0.10, 95%CI: 0.01-0.75). In multivariate model, the distribution of genotype for rs1051993 in PDR group was significantly different from that in DWR group (GT vs GG: OR: 0.07, 95%CI: 0.01-0.61, P<0.001). No association with DR was observed in other genotyped SNPs. CONCLUSION: The data suggest a significant association of the promoter variant rs1051993 in AGER gene with PDR in Chinese cohort with T2DM.

SURGICAL OUTCOMES OF 25-GAUGE PARS PLANA VITRECTOMY USING AIR AS AN INTERNAL TAMPONADE FOR PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT.

PURPOSE: To report surgical outcomes of 25-gauge pars plana vitrectomy using air as an internal tamponade for patients with primary rhegmatogenous retinal detachment (RRD). METHODS: A retrospective clinical study of 59 eyes of 59 consecutive patients presented with primary RRD at the Beijing Tongren Eye Center in China. From August 2016 to May 2018, medical records of the patients who underwent 25-gauge pars plana vitrectomy with air tamponade for RRD were reviewed. The main outcome measures were primary and final anatomical success (retinal re-attachment) rates, and postoperative complications. RESULTS: Of the 59 patients, aged 54.47 ± 11.81 years, 31 (52.5%) were men. Vitrectomy was performed 3 to 40 (averaged 16.98 ± 10.17) days after the onset of symptoms, and the mean follow-up period was 12.90 ± 5.92 months (ranging 6.07-26.10 months). Forty-two eyes (71.2%) had RRD with retinal breaks in the superior half of the retina, and the mean number of retinal breaks was 1.75 ± 0.94. Three eyes (5.1%) had RRD with giant retinal tears. Of the 59 eyes, 35 (59.3%) had RRD with inferior quadrants involved. Proliferative vitreoretinopathy (PVR) gradings were C1 in 2 (3.4%) eyes and B or below in 57 (96.6%) eyes. The primary and final anatomical success rates were 94.9% (56/59) and 98.3% (58/59), respectively. Of the three eyes which developed re-detachment of the retina, one eye had postoperative progression of PVR and two eyes were RRD associated with macular hole in high myopia. Postoperative complications included 5 eyes (8.5%) with serous choroidal detachment within 3 days after surgery and 4 eyes (6.8%) with macular epiretinal membrane formation 1 to 8 months after surgery. Secondary cataract surgery was performed in 13 of the 53 phakic eyes (24.5%) during follow-up. CONCLUSION: Small-gauge pars plana vitrectomy with air tamponade may be effective in treating selected cases of relatively simple primary RRD. Additional studies are needed to verify the efficacy of this surgical approach for more complicated cases such as those with giant retinal tears.

Etiologic Causes and Epidemiological Characteristics of Patients with Intraocular Foreign Bodies: Retrospective Analysis of 1340 Cases over Ten Years.

OBJECTIVE: Patients with intraocular foreign bodies were retrospectively analyzed. Population characteristics, pathogenic factors, and the outcomes during the past ten years were discussed. DESIGN: Retrospective case series study. METHOD: Medical records of 1340 patients hospitalized in Beijing Tongren Hospital from January 1, 2004, to December 31, 2013, were collected. RESULTS: Average age was 33.0 ± 13.8 (1-76) years old in 1340 patients. There were more males (1270, 94.8%) than females (70, 5.2%). Patients from outside of Beijing (82.1%, n = 1100) prevailed. Farmers (32.1%, n = 430) and workers (22.3%, n = 299) were the top two affected professions. Leading two causes were splashing of foreign bodies (SFB) (58.6%, n = 785) and explosives (31.8%, n = 426). More males than females were injured by SFB (59.4% versus 44.3%, P = 0.009). Firework injury was the commonest (41.6% versus 3.1%-15.3%, P < 0.05) in patients under nine. The annual percentages in patients over 50 increased (P < 0.001) and in patients by explosives decreased (P = 0.027). CONCLUSION: Most patients in this study were young males from outside of Beijing and farmers. SFB accounted most for patients over 10 years old and fireworks for those under ten. Patients over 50 increased while those by explosives decreased annually over the period.

The relationship between insulin resistance/ß-cell dysfunction and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus: the Desheng Diabetic Eye Study.

AIM: To investigate the relationship between insulin resistance (IR)/ß-cell dysfunction and diabetic retinopathy (DR) in Chinese patients with type 2 diabetes mellitus (T2DM), and to explore further whether there were differences in the relationship among diabetic patients with higher and lower body mass index (BMI). METHODS: Cross-sectional study. A total of 1466 subjects with T2DM were recruited in a local Desheng Community of urban Beijing from November 2009 to June 2012 for the cohort of Beijing Desheng Diabetic Eye Study. Standardized evaluation was carried out for each participant, including questionnaire, ocular and anthropometric examinations, and laboratory tests. Seven fields 30° color fundus photographs were used for DR grading according to the Early Treatment Diabetic Retinopathy Study protocols. Homeostatis Model Assessment (HOMA) method was employed for IR and ß-cell function assessment. RESULTS: After excluding those participants who were treated with insulin (n=352) or had missing data of fasting insulin (n=96), and further excluding those with poor quality of retinal photographs (n=10), a total of 1008 subjects were included for the final analysis, 406 (40.3%) were men and 602 (59.7%) were women, age ranging from 34 to 86 (64.87±8.28)y. Any DR (levels 14 and above) was present in 278 (27.6%) subjects. After adjusting for possible covariates, the presence of any DR did not correlate with HOMA IR [odds ratio (OR) 1.51, 95% confidence interval (CI) 0.87-2.61, P=0.14] or HOMA ß-cell (OR 0.71, 95%CI 0.40-1.26, P=0.25). After stratification by BMI, the presence of any DR was associated positively with HOMA IR (OR 2.46, 95%CI: 1.18-5.12, P=0.016), and negatively with HOMA ß-cell (OR 0.40, 95%CI: 0.19-0.87, P=0.021) in the group of patients with higher BMI (≥25 kg/m2). In the group of patients with lower BMI (<25 kg/m2), the presence of any DR was not associated with HOMA IR (OR 1.00, 95%CI: 0.43-2.33, P=1.00) or HOMA ß-cell (OR 1.41, 95%CI: 0.60-3.32, P=0.43). CONCLUSION: The data suggest that higher IR and lower ß-cell function are associated with the presence of DR in the subgroup of diabetic patients with higher BMI. However, this association is not statistically significant in diabetic patients with lower BMI.

The Beijing Desheng Diabetic Eye Study: rationale, design, methodology and baseline data.

AIM: To present the rationale, design, methodology, and the baseline data of the Beijing Desheng Diabetic Eye Study (BDDES), and to determine the prevalence of diabetic retinopathy (DR) and possible risk factors in patients with type 2 diabetes mellitus (T2DM) in an urban community of Beijing, China. METHODS: Community-based prospective cohort study of persons diagnosed with T2DM aged 30y or older. The main variables of interest are the presence and progression of DR as determined by the standardized ETDRS grading of seven fields fundus photographs. The presence and severity of DR were analyzed for possible correlations to non-genetic and genetic dispositions. RESULTS: A total of 1438 participants with data available for analysis, the prevalence of any DR was 35.4%. The prevalence of mild non-proliferative diabetic retinopathy (NPDR), moderate NPDR, severe NPDR, and proliferative diabetic retinopathy was 27.7%, 2.6%, 0.5% and 4.5%, respectively. By multiple logistic regression analysis, risk factors for the presence of any DR included male (P=0.031), lower income level (P=0.011), lower education background (P=0.022), longer duration of diabetes (P=0.001), younger age at diabetic onset (P=0.001), higher systolic blood pressure (P=0.007), higher glycosylated hemoglobin A1c levels (P=0.001), high albuminuria (P=0.03), and use of insulin (P<0.001). For vision-threatening DR, four factors were significant: younger age at diabetic onset (P<0.001), higher systolic blood pressure (P=0.042), high albuminuria (P<0.001), and use of insulin (P<0.001). CONCLUSION: The BDDES is the first large-scale ongoing cohort study of a Chinese urban population of persons with type 2 diabetes. Using standardized grading system comparable to large cohort studies from western populations, our baseline data shows that the prevalence of DR and major risk factors in this Chinese ethnic population are comparable to that found in the western population studies.

Subfoveal Choroidal and Macular Thickness Changes after Phacoemulsification Using Enhanced Depth Imaging Optical Coherence Tomography.

PURPOSE: To assess changes in the thickness of the subfoveal retina and choroid after phacoemulsification using enhanced depth imaging optical coherence tomography (EDI-OCT). METHODS: A prospective study was conducted on 100 patients. The subfoveal choroidal thickness (SFCT) was measured at 7 points and the retinal thickness was measured at 5 points (before surgery, and 1 day, 1 week, 1 month, and 3 months after surgery). RESULTS: The foveal choroidal thickness showed a thickening trend (but p > 0.05). Compared to the change from baseline to day 1, the changes from baseline were significantly different at nasal 3 mm and 6 mm at all other time points (all p < 0.05). Choroidal thickness changes at temporal 6 mm correlated negatively with intraocular pressure (IOP) at 1 week and 1 month; changes at nasal 3 mm correlated negatively with IOP at 1 week and 1 month (all p < 0.05); changes at nasal 3 mm, temporal 3 mm, and temporal 6 mm correlated with average ultrasonic energy. Choroidal thickness changes correlated with ultrasound (US) time at day 1. CONCLUSIONS: Uncomplicated phacoemulsification led to changes in choroidal thickness. IOP and choroidal thickness changes were negatively correlated. The foveal retinal thickness was correlated with age. SFCT was correlated with sex, axial length, IOP, and US time.

Outcomes of small gauge pars plicata vitrectomy for patients with persistent fetal vasculature: a report of 105 cases.

AIM: To evaluate the surgical outcomes in eyes with persistent fetal vasculatures (PFV) managed by small gauge pars plicata vitrectomy. METHODS: Consecutive patients with PFV treated by small gauge pars plicata vitrectomy at Beijing Tongren Eye Center between January 2010 and January 2013 were retrospectively reviewed. RESULTS: A total of 118 eyes of 105 patients with PFV were included and undergone small gauge pars plicata vitrectomy, of which 84 (71.2%) eyes had lensectomy and 16 (13.6%) eyes had lens aspiration and immediate intraocular lens implantation. The percentage of sutured scleral incision of 23 gauge vitrectomy (71.7%, 33/46) was higher than that of the 25 gauge vitrectomy (18.1%, 13/72). At last follow-up, visual acuity remained stable in 34 eyes (28.8%) and improved in 84 eyes (71.2%). Age at surgery (less than 2y), anterior type of PFV, and immediate IOL implantation were associated with postoperative improved visual acuity. Sixty five (55.1%) eyes had retinal detachment preoperatively, among which 33 (50.8%, 33/65) eyes had retinal reattachment or partial retinal reattachment. CONCLUSION: The results suggest that cases with PFV have a potential for developing good visual acuity after small gauge pars plicata vitrectomy with favorable anatomic outcomes and acceptable rate of serious surgical complications.

Association of choroidal thickness with early stages of diabetic retinopathy in type 2 diabetes.

AIM: To assess the correlation between choroidal thickness (CT) and the early stages of diabetic retinopathy (DR) in type 2 diabetic patients. METHODS: We divided 83 diabetic patients (51-80 years of age; 50 females) into non diabetic retinopathy group (NDR) and mild/moderate nonproliferative diabetic retinopathy (NPDR) group, and compared them with 26 non-diabetic control subjects (51-78 years of age; 16 females). Subfoveal choroidal thickness (SFCT) and parafoveal choroidal thickness (PFCT) were measured using enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT). Ocular health status, disease duration, body mass index, and hemoglobin A1c (HbA1c) were recorded. RESULTS: The mean ages of the NDR, NPDR, and control groups were 68.0±6.9y, 67.8±6.4y, and 65.1±6.3y, respectively (P=0.17). Pearson correlation of the right and left eyes for the control subjects was 0.95 and for the NDR subjects was 0.93. SFCT for the right eyes of the controls was 252.77± 41.10 µm, which was significantly thicker than that of the right eyes in NDR group (221.51±46.56 µm) and the worse eyes of the NPDR group (207.18±61.87 µm; ANOVA, P<0.01). In the diabetic patients pooled together, age was the only variable significantly associated with SFCT (multiple linear regression analysis, P=0.01). CONCLUSION: CT decreased significantly in the NDR and mild/moderate NPDR eyes compared with the control eyes. Age is significantly associated with SFCT in the diabetic patients. Diabetic choroidopathy may be present before clinical retinopathy.

Combined photodynamic therapy and ranibizumab for polypoidal choroidal vasculopathy: a 2-year result and systematic review.

AIM: To report a cohort of patients with polypoidal choroidal vasculopathy (PCV) treated with photodynamic therapy (PDT) followed by intravitreal ranibizumab injection 24-48h later, and to compare the results between eyes with PCV treated by PDT followed by intravitreal anti-vascular endothelial growth factor (VEGF) injection and intravitreal anti-VEGF injection followed by PDT by Meta-analysis. METHODS: Retrospective study and systematic literature review. Medical records of patients with PCV who were initially treated using PDT followed by intravitreal ranibizumab injection 24-48h after PDT and had completed at least 2y follow-up were reviewed and analyzed. Clinical data, including age, sex, best-corrected visual acuity (BCVA), fundus photograph, fluorescein angiography, indocyanine green angiography and optical coherence tomography were investigated. A systematic literature review was also conducted, and a visual outcome of studies over 1y was compared using Meta-analysis. RESULTS: A total of 52 patients were included in the study. Mean BCVA at baseline and follow-up at 1 or 2y were 0.71±0.61, 0.51±0.36 and 0.68±0.51 logMAR, respectively. The cumulative hazard rate for recurrence at 1 and 2y follow-up was 15.4% and 30.3% respectively. The percentage of eyes with polyps regression at 3, 12 and 24mo follow-up was 88.5%, 84.6% and 67.3% respectively. A Meta-analysis based on 22 independent studies showed the overall vision improvements at 1, 2 and 3y follow-up were 0.13±0.04 (P<0.001), 0.12±0.03 (P<0.001), 0.16±0.06 (P<0.001), respectively. The proportion of polyps regression at 1y follow-up was 64.6% (95%CI: 51.5%, 77.7%, P<0.001) in 434 eyes treated by intravitreal anti-VEGF agents before PDT and 76.0% (95%CI: 64.8%, 87.3%, P=0.001) in 199 eyes treated by intravitreal anti-VEGF agents after PDT. CONCLUSION: Intravitreal ranibizumab injection 24-48h following PDT effectively stabilizes visual acuity in the eye with PCV. PDT followed by intravitreal anti-VEGF agents may contribute to a relatively higher proportion of polyps' regression as compared to that of intravitreal anti-VEGF before PDT.

Association of macular pigment optical density with early stage of non-proliferative diabetic retinopathy in Chinese patients with type 2 diabetes mellitus.

AIM: To detect the association between macular pigment optical density (MPOD), which reflects the antioxidant ability of retina, and diabetic retinopathy (DR) and to investigate the correlated factors of MPOD. METHODS: Totally 435 subjects of urban Chinese were recruited to the study and divided into 3 groups: non-diabetes mellitus controls (NDM), diabetic patients without retinopathy (DWR), and patients with early stage of non-proliferative diabetic retinopathy (DR). Demographic and lifestyle characteristics were ascertained by questionnaire. A food-frequency questionnaire, general physical and ophthalmic examinations were completed for all participants. MPOD was measured by heterochromatic flicker photometry. Foveal thickness was measured by optical coherence tomography. The difference of MPOD among 3 groups was analyzed by analysis of covariance. The correlation analyses of MPOD with the candidate influence factors were assessed using the generalized estimating equations (GEE) model. RESULTS: Of the 435 participants, 34 could not perform the MPOD measurements. Final analysis included 401 subjects, including 48 were in DR group, 134 in DWR group, and 219 in NDM group. MPOD was not significantly different among DR (0.49±0.21), DWR (0.45±0.21), and NDM (0.49±0.17) groups (P=0.24) after adjustment for fasting plasma glycemia, central foveal thickness, green vegetables, Chinese wolfberry, carotene and vitamin E. For all the 401 participants included, MPOD was positively associated with central foveal thickness (E=0.0007, P=0.001), Chinese wolfberry (E=0.0345, P=0.01), and green vegetables (E=0.0596, P<0.001) intake. CONCLUSION: The data suggest that MPOD level is not statistically significantly influenced by the onset of diabetes or early stage of DR in the studied population. MPOD level is positively associated with thicker central foveal thickness and higher intake of foods containing carotenoids.

Retinal vessels caliber changes after strabismus surgery: results of 6mo follow-up.

AIM: To evaluate the effect of strabismus surgery on retinal vessels calibers with digital color fundus photographs. METHODS: Two hundred consecutive strabismus patients underwent surgery, and 118 patients (female/male, 55/63) who finished 6-month follow-up were finally included in this study. Optic disc-centered digital color fundus photographs of both eyes of all patients were taken prior to surgery and 6mo post surgery. The retinal vascular caliber of 116 operated eyes were measured using the computer program IVAN. The operated eyes were divided into 3 groups according to the surgical methods, recession of one muscle, one muscle recession and one muscle folding, one muscle resection and one muscle recession. The effect of number of altered muscles on retinal vessels was analyzed using statistic software SPSS 16.0. RESULTS: The mean age was 12.4±8.6y. Averaged central retinal artery equivalent (CRAE) of all patients was 120.31±23.02 µm preoperatively, and 122.87±15.93 µm six months after surgery. Averaged central retinal vein equivalent (CRVE) was 171.11±31.73 µm preoperatively and 175.02±21.00 µm postoperatively. There was no significant difference of averaged CRAE (P=0.22) or CRVE (P=0.19) before and after operation. Averaged arteriole to venule ratio (AVR) was 0.71±0.07 before surgery and 0.70±0.07 after surgery. Comparison of preoperative and postoperative retinal vessels calibers among different surgical groups did not show significant differences. Also, there was no advantage of rectus muscle folding to muscle resection. CONCLUSION: Up to 6mo after strabismus surgery, the retinal vascular calibers were not altered. No more than two muscles in one surgery are safe for retinal perfusion.

The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography.

AIM: To investigate the pattern of diurnal variations of choroidal thickness of macular region of healthyindividuals. METHODS: A prospective study of 32 healthy female subjects was conducted. Each subject underwent 1) a questionnaire on daily schedule, 2) the Pittsburgh Sleep Quality Index questionnaire (PSQI), and 3) ocular examinations including an eye dominance test, fundus photography, and sequential optical coherence tomography (OCT) imaging, on two separate days at five fixed 3h time intervals. Choroidal thickness was measured by two masked graders. RESULTS: A significant diurnal variation of choriodal thickness at fovea (P<0.001), at 500 µm nasal (P<0.001), temporal to fovea (P=0.01) or 1500 µm nasal to fovea (P=0.001) was observed. The median choroidal thickness peaked at 11:00 at fovea (P=0.01), at 500 µm nasal (P=0.009) and temporal (P=0.03) to fovea. The median amplitude of foveal choroidal thickness was 20.5 µm (13, 31) and 20.0 µm (12.5, 28.2) for the first and second series of measurements, respectively. The greater amplitude of foveal choroidal thickness was associated with thickner initial foveal choroidal thickness [0.05 (0.03, 0.08), P=0.01], dominant eye [10.51 (4.02, 14.60), P=0.04] in the multivariate linear regression. CONCLUSION: Our data show a significant diurnal variation of the choroidal thickness at fovea, at 500 µm nasal and temporal to fovea and 1500 µm nasal to fovea. Thicker initial foveal choroidal thickness and being dominant eye may influence the amplitude of foveal choroidal thickness.

C-reactive protein and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus.

AIM: To investigate the relationship between C-reactive protein (CRP) and diabetic retinopathy (DR) in a cohort of Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: Community-based observational cohort study. There were 1131 participants recruited from November 2009 to September 2011 in Desheng community in urban Beijing. Patients diagnosed T2DM were recruited and underwent a standardized evaluation consisting of a questionnaire, ocular and anthropometric examinations and laboratory investigation. The presence and severity of DR were assessed by seven fields 30° color fundus photographs. Subjects were then classified into groups with no DR, any DR, or vision-threatening DR. CRP was analyzed from serum of study subjects. RESULTS: A total of 1007 patients with T2DM were included for analysis, including 408 (40.5%) men and 599 (59.5%) women. The median CRP level was 1.5 mg/L for women and 1.1 mg/L for men (P=0.004, OR 0.37, 95% CI 0.18-0.74). After adjusting for possible covariates, higher levels of CRP were associated with lower prevalence of any DR (P=0.02, OR 0.55, 95% CI 0.35-0.89), but not associated with vision-threatening DR (P=0.62, OR 0.78, 95% CI 0.28-2.14). After stratification by sex, the inverse association between CRP and DR was found to be statistically significant in men (P=0.006, OR 0.35, 95% CI 0.16-0.73), but not in women (P=0.58, OR 0.88, 95% CI 0.29-1.16). CONCLUSION: The data drawn from a Chinese population with T2DM suggest that increasing CRP levels may be inversely associated with development of DR.

Relationship of retinal vascular calibre and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus: the Desheng Diabetic Eye Study.

AIMS: To describe the relationship of retinal arteriolar and venular calibre with diabetic retinopathy (DR) and related risk factors, including glucose levels and other biomarkers in a Chinese population with type 2 diabetes mellitus (T2DM). METHODS: A cross-sectional study. Patients with T2DM were recruited from a local community in urban Beijing. Seven fields 30° colour fundus photographs were taken and examined for the presence and severity of DR using a standardised grading system. Retinal vascular calibres were measured and expressed as average central retinal arteriolar and venular equivalent using a computer-based program. RESULTS: A total of 1340 patients with T2DM were included for analysis. Of these, 472 (35.22%) had DR. Wider retinal venular calibre, but not arteriolar calibre, was associated with increasing glucose and glycosylated haemoglobin A1c levels (p<0.006) and dyslipidaemia (p for trend <0.05). After adjusting for possible covariates, the higher quartile of retinal venular calibre was associated with higher prevalence of any DR (OR 2, 95% CI 1.36 to 2.95). Venular calibre increased from 224.33 µm in those without retinopathy to 231.21 µm in those with mild, 241.01 µm in those with moderate and 235.65 µm in those with severe retinopathy (p for trend <0.001). Arteriolar calibre was not associated with DR. CONCLUSIONS: In the current study, wider venular calibre, but not arteriolar calibre, was shown to be associated with development and increased severity of DR independently from other risk factors in a Chinese diabetic population.

Measurement of macular pigment optical density among healthy Chinese people and patients with early-stage age-related macular degeneration.

AIM: To measure the macular pigment optical density (MPOD) in healthy Chinese people and patients with early age-related macular degeneration (AMD). METHODS: Cross-sectional population based study. Demographic and lifestyle characteristics were ascertained by questionnaire. A food frequency questionnaire was completed for all participants. Participants underwent general physical and ophthalmic examinations and MPOD was measured by heterochromatic flicker photometry. Foveal architecture was measured by optical coherence tomography. RESULTS: MPOD of 225 participants (122 healthy and 103 early AMD) was 0.48±0.18. Patients with early AMD (0.52±0.19) tended to have higher MPOD levels than healthy people (0.47±0.17), but the difference was not statistically significant (P=0.06). Participants with carrot or corn oil intake every week tended to have higher levels of MPOD (P=0.002 and 0.008 respectively) while those with corn intake had relatively lower level of MPOD (P=0.01). MPOD increased with the center foveal thickness (P=0.01). CONCLUSION: Our findings show that there is no statistically significant association between MPOD and early AMD in the studied population. MPOD is related to center foveal thickness and diets would influence MPOD levels.

[The association of variable number of tandem repeats polymorphism in the endothelial nitric oxide synthase gene and diabetic retinopathy].

OBJECTIVE: To investigate the association between the variable number of tandem repeats (VNTR) polymorphism 4a/b in the endothelial nitric oxide synthase (eNOS) gene and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus. METHODS: cross-sectional study. A total of 278 type 2 diabetes patients were recruited, of whom 130 had DR, and 148 had diabetes without retinopathy (DWR). Of the 130 patients with DR, 34 had proliferative DR (PDR) and 96 had non-proliferative DR (NPDR). A number of 223 volunteers without diabetes from the same area were recruited as the control group. PCR and agarose gel electrophoresis methods were adopted to determine the 4a/b polymorphism genotypes of the eNOS gene. Statistical analysis was performed using the R statistical analysis package. Genotype distribution was compared using the χ(2) test. Numerical data were examined by Student t test. Genotypes and allele frequencies between cases and controls were compared using the χ(2) test or Fisher's exact test. Odd ratios (OR) and 95% confidence intervals (CI) were calculated according to the Woolf's equation. RESULTS: The frequencies of minor alleles (a) were 10.8% and 11.5% in the DR and DWR group, respectively. There were no statistical differences between the two groups (χ(2) = 0.07, P = 0.789). Also there were no statistical differences (χ(2) = 0.88; P = 0.643) in the distributions of the genotypes between DR group (bb 78.5%, ab 21.5%, aa 0.0%) and DWR group (bb 77.7%, ab 21.6%, aa 0.7%). Statistical differences were found in the frequencies of alleles, and the distributions of genotypes between diabetes group and the control group (χ(2) = 8.75, 10.39, P = 0.003, 0.006). However, after adjustment for age, blood pressure, cholesterol concentration, blood-fat and so on, it became insignificant (χ(2) = 0.97, 1.25, P = 3.224, 0.812). In the multiple regressions model including clinic factors such as the age of onset of diabetes, urinary albumin, insulin using, creatinine, glycated hemoglobin and fast glucose, no evidence showed that eNOS gene VNTR 4a/b was associated with diabetic retinopathy (OR = 0.37, 95% CI: 0.15-0.95). CONCLUSION: There was no significant association between eNOS gene VNTR 4a/b polymorphism and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus.