Volume 49 · Issue 12 · 2013

Myopic traction maculopathy is a group of ocular fundus diseases related to high myopia,which can severely impact on patients'visual function.It is well recognized that the abnormal of macular structure and function in the disease are resulted from various traction mechanisms,including the forces from posterior vitreous detachment,posterior vitreous cortex,and macular epiretinal membrane which acting on the inner retina,the force from posterior staphyloma which acting on the outer retina,and retinal intrinsic features such as the changes of inner limiting membrane and arterioles.The treatments are mainly based on surgery,including vitrectomy and scleral reinforcement surgery in order to relieve the retinal traction.The options of specific surgery procedures are still under debated.In this article,we reviewed the pathogenic mechanisms and therapeutic strategies of myopic traction maculopathy. (Chin J Ophthalmol,2013,49:1134-1137)

Because multifocal electroretinogram can be used to assess the function of posterior pole of the retina especially in the macula objectively,non-invasively and quantitatively,it was widely used in clinic.At present,more practical experience of clinical visual electrophysiological testing has been obtained and achieved,but there are still some questions such as standardization of the operation,combined diagnosis of morphology and function of macular diseases,follow-up visit and investigation of macular diseases.Therefore,the value of the visual electrophysiology especially multifocal technique in diagnosis of macular diseases was not fully embodied.No matter the development or the operation of the mutifocal system should be strictly followed by the standards of International Society of Clinical Electrophysiology for Vision.Functional changes would be observed before the morphological changes in some macular disease especially early stage of the diseases by the help of multifocal electrophysiological test.Also this test can be used to assess the macular function in some macular diseases that showed disaccord between functional and morphological changes.Furthermore,diseases of optic nerve and visual cortex would be investigated by expanding the use of multifocal technique such as new analysis methods,new test methods and research on the animal models which would help to understand more about the mechanisms and therapeutic approaches of ophthalmic diseases. (Chin J Ophthalmol,2013,49:1057-1060)

To determine the frequency range of a-b wave complex in the dark-and light-adapted electroretinogram (ERG) and to isolate the pure a-and b-waves.

Case series study.Full-field ERGs were recorded in 16 eyes of 8 normal volunteers from October to November 2011.Digital filtering technique was used to extract the a-and b-waves from dark-and light-adapted ERG responses.The timings of a-and b-wave were measured to determine the frequency range of a-b wave complex.Major frequency components were determined from power spectra using fast Fourier transform (FFT).The effect of different order settings in the digital filter were compared to investigate the optimum condition,where the oscillatory potential (OP) was completely removed while the amplitudes and phases of the a-and b-waves were less affected.The Student-t test was used to compare the frequency range of a-b wave complex in dark-and light-adapted ERG.

The averaged frequency range of the dark-adapted a-b wave complex was from (14.99±2.39) to (25.35±3.77) Hz,compared with (25.22±6.56) to (32.47±3.68) Hz for the light-adapted ab wave complex,respectively,indicating the frequency range of the dark-adapted a-b wave complex was significantly less than the light-adapted a-b wave complex (t=7.910,7.693;bothP<0.01).The third order of the digital filter and a passband of 1 to 45 Hz was the best choice in term of removing the high frequency OP from the waveform of ERG and keeping the amplitude and phase of the a-and bwaves.

The frequency of a-b wave complex is lower than that of OP.Therefore the a-and b-waves can be isolated from OP using different digital filter settings in human ERG.A third order and a passband of 1 to 45 Hz is the best choice to extract pure a-and b-waves from the original ERG. (Chin J Ophthalmol,2013,49:1064-1068)

To observe the fundus features of nanophthalmos with or without secondary glaucoma using spectral domain optical coherence tomography (SD-OCT).

It was a retrospective case-series study.Twenty-three eyes of 12 patients (6 female,6 male) who were clinically identified to be nanophthalmos (axial length≤20.0 mm) in Zhongshan Ophthalmic Center from June 2008 to December 2010 and twenty-three eyes of 23 age and sex matched normal controls were included in this study.All patients underwent ophthalmological examinations including best-corrected visual acuity,refraction,slit-lamp biomicroscopy and fundus examination,Goldmann applanation tonometry,A-scan and B-scan ultrasound examinations,ultrasound biomicroscopy,fundus photography and spectral domain optical coherence tomography (SD-OCT).All examinations were carried out with natural pupil.The fundus features detected by OCT were compared between nanophthalmos and normal controls,and among nanophthalmos with or without secondary glaucoma.Independent-samples t test was used to analyze the difference of retinal thickness between nanophthalmoic eyes and controls and also between nanophthalmoic eyes with and without secondary glaucoma.Pearson correlation analysis was used to analyze the correlation between axial length and macular retinal thickness.

The average age of 12 patients was (25.0±13.1) years,and the mean axial length was (17.30±1.66) mm.Thirteen eyes suffered from secondary glaucoma because of angle closure with average intraocular pressure (IOP) of (28.62±9.18) mm Hg (1 mm Hg=0.133 kPa).The average IOP of the other 10 eyes without secondary glaucoma was (14.96±3.21) mm Hg.OCT images revealed thickening of the retina in macular fovea,with residual retinal nerve fiber layer,ganglion cell layer,inner plexiform layer,inner nuclear layer,outer plexiform layer,and broadened outer nuclear layer in 23 eyes with nanophthalmos.Pre-retinal folds were seen in 5 eyes with macular cysts.Shallow serous retinal detachment was found in 3 eyes,2 of which showed focal thickening of retinal pigment epithelium as leopard spots.The cup were not obvious and retina around optic nerve head was thickened in 10 eyes without secondary glaucoma and 4 eyes with secondary early glaucoma,which seemed to be pseudopapilloedema.The other 9 eyes with secondary late glaucoma revealed enlarged cup.The mean macular foveal thickness of nanophthalmic eyes[ (335.65±91.45) μm] was significantly thickened than normal control group[ (192.72±11.18) μm] (t=10.50,P=0.000).The mean macular foveal thickness of nanophthalmos with glaucoma[ (323.70±104.09) μm] was thinner than those without glaucoma[ (403.50±130.24) μm] (t=3.50,P=0.002).Macular foveal thickness were negatively related with axial length in both nanophthalmos with and without secondary glaucoma (R=-0.797,P=0.001).

Macular hypoplasia and crowded optic nerve head are two important characteristic of fundus appearances in nanophthamos.SD-OCT can clearly reveal the changes of macular retina and optic nerve head.SD-OCT will be a very useful tool to help diagnose nanophthamos and evaluate its possible complications. (Chin J Ophthalmol,2013,49:1069-1074)

To investigate the incidence,duration and consequences of persistent submacular fluid after pars plana vitrectomy (PPV) and scleral buckling surgery (SB) in rhegmatogenous retinal detachment,thus to explore the clinical association between persistent SMF and different surgical methods,and simultaneously,to study the effect of persistent submacular fluid on visual outcome.

It was a retrospective case-series study.Ninety-two qualified eyes including 54 eyes of males and 38 eyes of females with rhegmatogenous retinal detachment which had been performed PPV or SB were recruited.The average age of the patients was (45.8±15.3) years with a age-range from 15 to 76 years.The inclusion criteria was as follows,the macula-off rhegmatogenous retinal detachments without macular hole and obvious proliferative vitreoretinopathy,the retina was completely reattached 1 month after operation and no redetachment was found by ophthalmoscope and B scan till the last follow-up,the minimal follow-up time was 1 year and the submacular fluid must have been dissolved for at least 6 months.All patients underwent thorough ophthalmologic examinations before and after operation,Those patients in whom a persistent submacular fluid was seen on optical coherence tomography (OCT) at 1 month after operation performed follow-up with repeat of the investigations at 3,6 and 12 months after surgery,If the abnormality resolved,further observations were continued to undertake for 6 months or more till the last follow-up.Rank-sum test,χ²-test and Fisher exact test were applied respectively to analyze for statistical analysis.

The incidence of persistent submacular fluid at 1 month after surgery in the PPV and SB group was 13.9% (5/36) and 48.2% (27/56).Six months later however,the figure expressed as percentage was 2.8% (1/36) and 23.2% (18/28) correspondingly.Persistent submacular fluid was more frequent in eyes with inferior breaks (64.3%) than that with superior ones (13.9%),making a significant differences (χ²=17.38,P<0.01).The persistent submacular fluid group showed worse best-corrected visual acuity than no persistent submacular fluid group 6 and 12 months after surgery (t=2.525,t=2.254,bothP<0.05).Comparing the visual acuity (VA) between the eyes with or without persistent submacular fluid 6,12 months after surgery and the lastest followed-up among the ever suffered eyes,a statistically significant differences presented in late stages (average VA:0.47±0.29,0.30±0.16; 0.44±0.28,0.27±0.15;0.42±0.22,0.27±0.19;t=2.114,2.207,2.068;allP<0.05),though there were no significant differences in the first three months (average VA:0.70±0.33,0.63±0.37; 0.50±0.25,0.45±0.22;t=0.556,0.601;bothP>0.05).

Persistent submacular fluid presents in both surgical procedures but it is more frequent after buckling surgery than vitrectomy,the selection of patients,the location of retinal breaks and the duration of detachment may be the potential influencing factors.Persistent submacular fluid after retinal detachment surgery is responsible for delayed recovery,and may affect the final visual outcome.The longer it lasts,the more harm may it do. (Chin J Ophthalmol,2013,49:1075-1080)

To detect the correlation of retinal sensitivity,visual acuity and central macular thickness in patients with different types of diabetic macular edema (DME),macular function were evaluated by measuring the sensitivity,fixation pattern of the macular was examined by fundusrelated microperimetry,then analyzed and compared the results with best-corrected visual acuity (BCVA) and foveal retinal thickness measured by optical coherence tomography (OCT).

A restrospective case-series study.In a prospective,observational case series study,52 consecutive patients (83 eyes) with diabetic macular edema were included.Sex,age,BMI,education,type of DM,duration,treatment,laboratory examinations,history of cardiovascular disease,hypertension,hyperlipidemia,diabetic nephropathy,and cigarette use were documented.Logarithm of the minimum angle of resolution (log MAR) BCVA was evaluated using the international vision test chart.Foveal thickness was measured by OCT.Mean retinal sensitivities,fixation stability and position was investigated with microperimetry.Variables related with BCVA,foveal thickness and mean retinal sensitivities were analyzed in different types of DME patients using one-way ANOVA or Kruskal-Wallis test.As for fixation,Fisher exact test was chosen.Pearson Correlation analysis was performed to evaluate the association between these variables.Spearman correlation analysis was used for ordinal data.The correlation between retinal sensitivities and all the variables examined were analyzed under multiple regression analysis.

Eighty-three eyes were included in this study.Forty-seven eyes (56.63%) were graded as focal DME,20 eyes (24.10%) as diffuse DME,5 eyes (6.02%) as ischemic DME and 11 eyes (13.25%) as proliferative DME.Comparison between different types of DME patients showed statistically significant difference in mean log MAR BCVA (F=12.737,P<0.01),mean OCT foveal thickness (H=31.504,P<0.01),mean central retinal sensitivities (F=14.760,P<0.01),and patterns of fixation,which were also statistically correlated (χ²=23.47,21.01;P<0.01).It was a positive correlation between OCT foveal thickness and logMAR BCVA in patients with focal,diffuse and ischemic DME (r=0.56,-0.62;P<0.01),but not with proliferative DME (r=0.43,P=0.19).While central retinal sensitivities were also negative correlation between OCT foveal thickness and log MAR BCVA (r=-0.62,-0.68;P<0.01).Multiple regression analysis showed that central retinal sensitivity was inversely correlated with LogMAR and retinal thickness (t=-5.52,-4.24;P<0.01).

There are statistically significant difference in macular morphology and vision function between different types of DME patients.The progression of DME are expressed gradually from focal,diffuse to ischemic type.DME could be fully evaluated by measuring macular sensitivity,fixation pattern with microperimetry as well as macular thickness measurement with OCT and visual acuity determination comprehensively. (Chin J Ophthalmol,2013,49:1081-1088)

To observe the imaging features of fundus autofluorescence (FAF) in patients with multiple evanescent white dot syndrome (MEWDS) .

Retrospective case-series study.Eight cases of MEWDS patients visited Xingtai eye hospital between January 2009 and December 2010 were included in this study.Three males and 5 females,aged from 19 to 48 years,mean age was 33 years old.The span between onset and visit to the hospital was between 2 to 12 days,the average time was 6.5 days.All the patients underwent comprehensive ophthalmic examination and fundus color photography,FAF,fluorescein angiography (FFA),indocyanine green angiography (ICGA) by HRA-2.Two different spectrums of autofluorescence excited by laser of 488 nm and 787 nm were recorded,which were related to lipofuscin and melanin respectively.Dynamic imaging changes in different stages were observed and compared.The autofluoresce of fundus with white dot was paid extra attention.

The white dots in 8 eyes showed strong autofluorescence with a vague boundary in the FAF image excited by laser of 488 nm but normal autofluorescence under the FAF_787nm.The strong autofluorescence of 488 nm agreed with the white dots in the fundus photograph,hyperfluorescence lesions in FFA and the hypofluorescence focus in the later stage of ICGA.After the disease cured,the hyperfluorescence lesions in FFA also faded.

The fundus autofluorescence features of patients with MEWDS are hyperfluorescence in the site of white dots in FAF_488nm.It is the characteristic change of this disease. (Chin J Ophthalmol,2013,49:1089-1093)

To compare the efficacy of photodynamic therapy (PDT) alone,intravitreal anti-vascular endothelial growth factor (VEGF) therapy alone,and the combination of the two therapies for polypoid choroidal vasculopathy (PCV) .

Systematic review.A computerized search was conducted in Pubmed,Biosis Preview,Cochrane Library,and Embase.Studies comparing any two of the above three treatment strategies were enrolled in the study.Meta-analysis of pairwise comparisons of the three approaches was conducted.The primary endpoint was the proportion of patients with complete regression of polyps.Other endpoints included best corrected visual acuity (BCVA),central retinal thickness (CRT),number of treatments.

A total of 13 comparative studies were obtained,including 1 randomized controlled trials (RCT) and 12 retrospective comparative study (RCS).Four studies compared anti-VEGF monotherapy with PDT monotherapy.Seven studies compared PDT monotherapy with combination therapy.Four studies compared anti-VEGF monotherapy with combination therapy.Considering the RCT and RCS results: PDT was superior to anti-VEGF in achieving complete regression of polyps at month 6 (P=0.004),although BCVA and CRT showed no significant difference at 12-month follow-up.There was no significant difference in BCVA,CRT,and the proportion of patients with complete regression of polyps between PDT and combination group at 12 months follow-up.However,combination therapy showed more promising result in improving visual acuity at 24 months (P=0.05),with fewer PDT needed than in PDT monotherapy.Combination therapy was superior to anti-VEGF in achieving complete regression of polyps and the number of injections needed tended to be fewer.BCVA improvement and CRT reduction showed no significant difference at 12-month follow-up.

PDT with or without anti-VEGF therapy is superior to anti-VEGF monotherapy in achieving complete polyp regression,and combination therapy appeared to result in better visual outcome than PDT monotherapy in the long term (2 years). (Chin J Ophthalmol,2013,49:1094-1103)

To identify the pathogenic mutation in a four-generation Chinese family with autosomal dominant retinitis pigmentosa (ADRP) and to analyze its associated clinical phenotypes.

Twelve participants from the index family were recruited,including 5 patients,6 asymptomatic siblings,and one spouse.All participants underwent ophthalmic examinations,including best-corrected visual acuity (BCVA),visual field (VF) testing,fundus photography,and full-field flash electroretinography (ERG).Targeted sequence capture array technique with next-generation of high throughput sequencing (NGS) was performed to detect variants in 189 hereditary retinal disease (HRD) related genes,comprising 179 identified HRD-causing genes and 10 potential causative genes which were involved in pre-messenger RNA (pre-mRNA) splicing.Variants detected by targeted sequencing were filtered by bioinformatic analyses,validated by Sanger sequencing and intra-familiar analysis.Genotype-phenotype correlation was also analyzed.

SNRNP200p.S1087L was identified as the disease causative mutation for this family by targeted sequencing and optimized bioinformatic analyses.This family demonstrated early onset of the disease by presenting nyctalopia among 6 to 8 years old,performed rapid disease progression and severely impaired visual function by displaying loss of VF among 14 to 17 years old and decreased central vision among 21 to 28 years old.The fundus presentations and ERG results showed typical RP presentations.

SNRNP200p.S1087L is identified as a hotspot mutation but correlates with distinct phenotypes in the present family,including early onset of the disease,rapid disease progression,and severely impaired visual function.This study also give evidence to that molecular diagnostic platform for HRD can improve the detection rate of causative genes/mutations in HRD patients,thus providing important approaches for further investigation of the genetic causes for HRD. (Chin J Ophthalmol,2013,49:1104-1110)

To investigate the mechanism and inhibitory effects of overexpression of 15-lipoxygenase-1 inhibiting oxygen-induced retinal neovascularization in mice.

Experimental study.Eighty-eight 7-day-old C57BL/6J mice were randomly divided into the normal control group,induced model group,gene treated group and empty vector group with 22 mice in each group.The mice with their mothers were arisen in 75%±2% O ₂environment for 5 days and then returned to normoxia for 5 days to establish the oxygen-induced retinopathy (OIR) model.At postnatal day 12,the gene treated group was received an intravitreous injection of Ad-15-LOX-1-EGFP at 1.0μl,while the empty vector group was received the same volume of Ad-EGFP.At postnatal day 17,real-time PCR and Western Blot methods were used to detect the mRNA and protein expression levels of 15-LOX-1,peroxisome proliferator-activated receptorγ (PPAR-γ),vascular endothelial growth factor-A (VEGFA) and vascular endothelial growth factor receptor 2 (VEGFR-2) in the retina.The relative retinal nonperfusion and neovascularization areas were evaluated by FITC-dextran fluorescein angiography on flatmounted retina.The number of endothelial cell nuclei breaking through the inner limiting membrane (ILM) was counted on hematoxylin and eosin-stained retinal section.Rank sum test and one-way ANOVA were used to assess statistical significance within groups.

The 15-LOX-1 and PPAR-γmRNA and protein expression levels were higher in gene treated group (15-LOX-1:2.17±0.25,1.45±0.10;PPAR-γ:2.12±0.29,0.85±0.03) than those in induced model group (15-LOX-1: 0.62±0.03,0.66±0.04;PPAR-γ:0.67±0.18,0.48±0.03) and empty vector group (15-LOX-1: 0.51±0.14,0.57±0.03;PPAR-γ:1.07±0.09,0.52±0.02) (t_15-LOX-1=12.511,13.402,bothP<0.01;t_PPAR-r=9.420,6.813,bothP<0.01).On the contrary,VEGF-A and VEGFR-2 expression levels were lower in gene treated group (VEGF-A:0.87±0.07,0.34±0.01;VEGFR-2:1.02±0.12,0.45±0.03) than those in induced model group (VEGF-A:3.49±0.53,0.74±0.04; VEGFR-2: 2.28±0.44,0.82±0.01) and empty vector group (VEGF-A:2.30±0.25,0.69±0.02;VEGFR-2: 1.88±0.16,0.76±0.03) (t _VEGF-A=10.662,5.843,bothP<0.01;t_VEGFR-2=6.731,4.763,bothP<0.01).The relative retinal non-perfusion and neovascularization areas were significantly smaller,and the number of endothelial cell nuclei breaking through the ILM was obviously lower in gene treated group (5.88±1.12;9.37±1.85;1.25±0.89) than those in induced model group (21.25±2.87; 24.13±4.29;60.63±10.82) and empty vector group (19.50±1.78;23.13±3.52;54.63±7.63) (P<0.01;P<0.01).

Overexpression of 15-LOX-1 inhibits ORI neovascularization in mice via upregulation of PPAR-γand down-regulation of VEGF-A and VEGFR-2 expression. (Chin J Ophthalmol,2013,49:1111-1117)

To observe the visual quality of aspherical intraocular lens (IOL) implantation in traumatic cataract patients.

Prospective clinical study.96 traumatic cataract patients (96 eyes) suffered from penetrating corneal trauma chosen from the first affiliated hospital of Zhengzhou university during June 2009 to June 2012.They were divided into two groups based on the different type of intraocular lens.The experimental group (48 eyes) was implanted with aspherical IOL and the control group (48 eyes) was implanted with traditional sphere IOL.Uncorrected visual acuity (UCVA),best corrected visual acuity (BCVA),contrast sensitivity (CS) and stereoscopic vision were observed at 1 month,3 months,and 6 months after surgery.At the same time,questionnaire survey about the satisfaction of patients was also performed.The t test was used to compare the preoprative general condition,postoperative visual acuity,contrast sensitivity and stereoscopic vision of the two groups,and the rank sum test was used to compare the astigmatism and the satisfaction of patients.

There was no significant difference in UCVA (t=1.37,1.28,0.71,P>0.05) between the experimental group (0.56±0.22,0.68±0.13,0.84±0.15) and the control group (0.51±0.17,0.61±0.20,0.81±0.17) at three time points.There was no significant difference in BCVA (t=0.87,1.38,1.39,P>0.05) between the experimental group (0.62±0.13,0.74±0.21,0.87±0.10) and the control group (0.57±0.25,0.69±0.22,0.84±0.15).The same result happened in stereoscopic vision at 6 months after surgery (far stereopsis:123.5±7.8 vs 126.9±5.9,t=0.64,P>0.05;near stereopsis:90.5±7.8 vs 95.2±3.5;t=1.36,P>0.05) between experimental group and control group.The contrast sensitivity of the experimental group in every stage (3 c/d:1.52±0.18,6 c/d:1.68±0.19,12 c/d:1.29±0.14,18 c/d:1.04±0.20) was superior to the control group (3 c/d:1.49±0.27,6 c/d:1.57±0.21,12 c/d:1.14±0.20,18 c/d:0.85±0.14),especially on the glare sensitivity (the experimental group:3 c/d:1.40±0.15,6 c/d:1.52±0.22,12 c/d:1.21±0.18,18 c/d: 0.91±0.14,the control group:3 c/d:1.13±0.13,6 c/d:1.13±0.28,12 c/d:0.92±0.13,18 c/d: 0.54±0.16) Compared two groups of difference have statistical significance (free from glare:3 c/d:t=2.829,6 c/d:t=4.092,12 c/d:t=3.055,18 c/d:t=2.093;glare:3 c/d:t=2.650,6 c/d:t=3.105,12 c/d:t=3.395,18 c/d:t=2.215;P<0.05).Questionnaire survey showed the experimental group (72.9%) was statistically significantly higher (t=3.016,P<0.05) than that in the control group (54.1%) on the satisfaction of patients.

The visual quality with implantation of aspherical IOL in traumatic cataract patients is superior to traditional sphere IOL.Aspherical IOL is more appropriate for the patients with small and peripheral corneal scar.It can reduce the visual function damage to minimum caused by trauma. (Chin J Ophthalmol,2013,49:1118-1123)