Microstructural morphology and visual acuity outcome in eyes with epiretinal membrane before,during,and after membrane peeling in intraoperative optical coherence tomography assisted macular surgery

AIM:To measure the difference of intraoperative central macular thickness(CMT)before,during,and after membrane peeling and investigate the influence of intraoperative macular stretching on postoperative best corrected visual acuity(BCVA)outcome and postoperative CMT development.METHODS:A total of 59 eyes of 59 patients who underwent vitreoretinal surgery for epiretinal membrane was analyzed.Videos with intraoperative optical coherence tomography(OCT)were recorded.Difference of intraoperative CMT before,during,and after peeling was measured.Pre-and postoperatively obtained BCVA and spectral-domain OCT images were analyzed.RESULTS:Mean age of the patients was 70±8.13y(range 46-86y).Mean baseline BCVA was 0.49±0.27 log MAR(range 0.1-1.3).Three and six months postoperatively the mean BCVA was 0.36±0.25(P=0.01 vs baseline)and 0.38±0.35(P=0.08 vs baseline)log MAR respectively.Mean stretch of the macula during surgery was 29%from baseline(range 2%-159%).Intraoperative findings of macular stretching did not correlate with visual acuity outcome within 6mo after surgery(r=-0.06,P=0.72).However,extent of macular stretching during surgery significantly correlated with less reduction of CMT at the fovea centralis(r=-0.43,P<0.01)and 1 mm nasal and temporal from the fovea(r=-0.37,P=0.02 and r=-0.50,P<0.01 respectively)3mo postoperatively.CONCLUSION:The extent of retinal stretching during membrane peeling may predict the development of postoperative central retinal thickness,though there is no correlation with visual acuity development within the first 6mo postoperatively.

Predictive factors of epiretinal membrane in complicated rhegmatogenous retinal detachment tamponaded with silicone oil

AIM:To determine the incidence and predictive factors for epiretinal membrane(ERM)formation in eyes with complicated primary rhegmatogenous retinal detachment(RRD)tamponaded with silicone oil(SO).METHODS:This retrospective case-control study included 141 consecutive patients with(51 eyes)and without(90 eyes)ERM formation after primary pars plana vitrectomy(PPV)and SO tamponade for complicated RRD.The risk factors for ERM were assessed using logistic regression analysis.RESULTS:The prevalence of postoperative ERM was 36.2%(51/141).Multivariate logistic regression analysis showed that the risk factors for ERM in SO-tamponaded eyes included preoperative proliferative vitreoretinopathy[PVR;odds ratio(OR),2.578;95%confidence interval(CI)1.580–4.205,P<0.001],preoperative choroidal detachment(OR,4.454;95%CI 1.369–14.498,P=0.013),and photocoagulation energy(OR,2.700;95%CI 1.047–6.962,P=0.040).The duration of the preoperative symptoms,intraocular SO tamponade time,giant retinal tear,preoperative vitreous hemorrhage,preoperative bestcorrected visual acuity,number of breaks,quadrants of RRD,axial length,and photocoagulation points were not predictive factors for ERM formation.CONCLUSION:Preoperative PVR,choroidal detachment,and photocoagulation energy are risk factors of ERM formation after complicated RRD repair.Better ophthalmic care as well as patient education are necessary for such patients with risk factors.

Epiretinal membrane related vascular changes in diabetic eyes evaluated with optical coherence tomography angiography

AIM:To evaluate the retinochoroidal microvascular circulation and anatomical structure of diabetic and nondiabetic patients with epiretinal membrane(ERM)with the help of optical coherence tomography angiography(OCT-A)and compare them with healthy control subjects.METHODS:In this prospective,cross-sectional study,a total of 165 eyes were evaluated,including 50 eyes of patients with diabetic ERM,54 eyes of idiopathic ERM(iERM)patients,and 61 eyes of healthy controls.Macula and disc angiography was performed by OCT-A.Macular vessel density(VD)ratio was evaluated by dividing the VD of the foveal region by the VD of the parafoveal region.Statistical calculations were evaluated at the 95%confidence interval.RESULTS:Macula superficial VD values of ERM cases were lower than that in the control group,while foveal VD was higher in ERM cases.Macula deep VD values of ERM cases were lower in all quadrants,except the fovea.The width of the foveal avascular zone(FAZ)area was significantly lower in the ERM groups,and the FAZ width was lowest in iERM group.Macula superficial VD ratio was significantly higher in the ERM groups,but there was no significant difference between ERM groups.Macula deep VD ratio was significantly higher in the iERM group than in the control group.CONCLUSION:Diabetic and idiopathic ERMs differ in their mechanism of formation and clinical presentation,as well as their effect on retinal vascular structures.If the relationship of increase of retinal thickness with vascular integrity can be demonstrated with OCT-A,then,OCT-A can be used as a guide for ERM prognosis.

Superficial foveal avascular zone area changes before and after idiopathic epiretinal membrane surgery

To investigate the foveal morphological changes and foveal avascular zone（FAZ）area before and after epiretinal membrane（ERM）surgery.Twenty-two eyes with treatmentnaive ERM were included in this retrospective study.The central foveal thickness（CFT）and FAZ area were measured via swept-source optical coherence tomography（SS-OCT）and OCT angiography pre-and postoperatively.The unaffected fellow eyes were used as controls.The preoperative superficial FAZ area was significantly smaller in patients（0.08±0.04 mm^2）than in controls（0.33±0.09 mm^2;P〈0.001）.The postoperative superficial FAZ（0.12±0.06 mm^2）area was significantly greater than the preoperative area（P〈0.001）.The preoperative superficial FAZ area was strongly negatively correlated with CFT（P〈0.001,rho=-0.763）.ERM induced significant foveal morphological changes and reduction of the superficial FAZ area.Foveal thickness was restored and FAZ area increased postoperatively.However,the process is rather slow and the recovery is incomplete.

Epiretinal membrane following pars plana vitrectomy for rhegmatogenous retinal detachment repair

AIM: To determine the rate and possible contributors for post-pars plana vitrectomy(PPV) epiretinal membrane(ERM) in patients treated for rhegmatogenous retinal detachment(RRD). METHODS: This prospective, nonrandomized study comprised 47 consecutive patients(47 eyes) with acute RRD treated with 23 G post-PPV. All participants were followed prospectively for 6 mo for the development of ERM using spectral domain optical coherence tomography. Preoperative and intraoperative data were collected by questionnaires to surgeons. Main outcome measure was the percentage of the ERM formation following post-PPV for RRD. RESULTS: ERM developed postoperatively in 23 eyes(48.9%), none necessitated surgical removal. There was a statistically significant difference between patients with and without ERM postoperatively in preoperative best corrected visual acuity(median log MAR 1.9 vs 0.3, respectively;P=0.003) rate of macula-off(69.6% vs 37.5%, respectively, P=0.028), and rate of ≥5 cryo-applications(55.6% and 18.8%, respectively, P=0.039). ERM developed mainly between the 1st and 3rd months of follow-up. Macula-off status increased the risk of ERM, with the odds ratio of 3.81(P=0.031). CONCLUSION: ERM is a frequent post RRD finding, and its development is associated with macula-off RRD.

Correlation between choroidal thickness and intraocular pressure after 23-gauge vitrectomy for idiopathic epiretinal membrane

AIM： To determine the relationship between the subfoveal choroidal thickness（CT） and intraocular pressure（IOP） following idiopathic epiretinal membrane（ERM） surgery.METHODS： Retrospective observational case series of patients who had undergone 23-gauge vitrectomy for an ERM. The measurements of CT and IOP were done at the baseline and 1 d, 1 wk, 1, 3, 6, and 12 mo after the surgery.RESULTS： Forty-four eyes of 43 patients with a mean age of 69.8±9.5 y were studied. The CT was 200.8±86.3 μm at the baseline, 210.1±83.5 μm at 1 d, 213.2±85.4 μm at 1 wk, 203.1±84.0 μm at 1 mo, 197.5±85.5 μm at 3 mo, 197.7±84.0 μm at 6 mo, and 191.2±86.8 μm at 12 mo after surgery. The CT on day 1 and week 1 after the surgery was significantly thicker than that at the baseline CT（P=0.0023 and P〈0.0001）. The CT at 12 mo after surgery was significantly thinner than the baseline（P=0.0062）. The IOP on day 1 and week 1 were significantly lower than the baseline（P〈0.0001 and P=0.0042）. The IOP at 1, 3, 6, and 12 mo after surgery were significantly higher than the baseline IOP（P=0.0087, P=0.0023, P〈0.00051, and P〈0.0001）. The rates of changes in the CT between baseline and day 1 and week 1 were significantly and negatively correlated with the rates of change in the IOP（P〈0.0001 and P=0.046）. In the group with the IOP change rate of-30% or less at 1 d postoperatively, the change rate of CT was-21.1% to 31.2%（9.8%±12.4%） and in the group of-29% or more, it was-8.9% to 28.0%（2.6%±8.9%）. The change rate of CT in the group with the IOP change rate of-30% or less was significantly higher than the group of-29% or more（P=0.016）.CONCLUSION： CT increases soon after the ERM surgery which is probably due to the transient hypotony, showing that IOP may be a significant confounding factor for CT.

The impact of macular surgery in different grades of epiretinal membrane

AIM：To assess the impact of macular surgery on the functional and anatomic outcomes of the patients in different grades of epiretinal membrane（ERM）.METHODS：Seventy-one eyes of 71 patients who underwent 23-gauge transconjunctival sutureless pars plana vitrectomy for primary isolated ERM were evaluated in this study.RESULTS：There were 38 females（53.5%） and 33 males（46.5%）.The average age of the patients was 68.1 y（range 42-89 y）.Mean follow up period was 14 mo（range 6-26 mo）.The cases were divided into two subgroups of cellophane maculopathy（CM） and macular pucker（MP）.An improvement was observed in the postoperative best-corrected visual acuity（BCVA）,as well as a decrement in central foveal thickness（CFT） in both groups（both of these being statistically significant;P=0.001）.In comparison between two groups,it was found that there was a significant improvement on BCVA and CFT in CM group than MP group（P=0.01）.Furthermore,the postoperative fundus findings regarding RPE alterations and macular edema were significantly higher in MP group when compared to the CM group（P=0.01）.CONCLUSION：ERM and internal limiting membrane peeling surgery can lead to a significant reduction of CFT and visual improvements in idiopathic ERM.A long-term ERM persistence will cause unrecoverable retinal damage and visual loss.

Post-operative visual outcomes based on morphological staging of idiopathic epiretinal membranes on OCT

AIM:To evaluate the recently described optical coherence tomography(OCT)based classification of epiretinal membrane(ERM)and its usefulness in predicting the functional outcome.METHODS:A retrospective observational review of OCT scans of patients with the diagnosis of idiopathic ERM was carried out from January 2016 to June 2021.All consecutive images diagnosed with any stage of idiopathic ERM and fulfilled the eligibility criteria were included in the analysis.ERM was identified on OCT scans as a thin hyperreflective layer over the inner layers of retina.OCT scans of patients with ERM who underwent vitrectomy,were independently staged as per the new classification by two independent retinal surgeons to form a consensus on stage.Best corrected visual acuity(BCVA)in logMAR scale and central subfield thickness(CST)on pre-and post-operative spectral domain OCT scans were the variables noted for all patients at the time of diagnosis and at 6 and 12 mo follow up visit after undergoing intervention.Partial correlation coefficient was computed between BCVA(logMAR)and CST by ERM stage adjusting by baseline measures.RESULTS:Clinical charts of 74 patients with idiopathic ERM were assessed.Clinically significant improvement in BCVA overtime was observed with significant difference in median visual acuity of patients with StageⅡ-ⅣERM with P<0.001.The median CST of all patients with stageⅡ-ⅣERM showed similar consistent improvement with P<0.001 from baseline to 12^(th)month.Our results showed not only gain in visual acuity but also shift from baseline to anatomical normalization of CST in stageⅡ.We found a decrease in CST with difference of 166μm and 151μm in stageⅢand stageⅣrespectively.Our results remained consistent with the hypothesis of improved visual outcomes with all stages of ERM with adjusted moderate linear correlation between visual acuity and CST in stageⅡ-Ⅳ(r>0.3).CONCLUSION:Equally significant visual outcomes of patients with ERM stagedⅡ-Ⅳand therefore can be counselled for improved visual acuity after surgical removal of ERM with improvement up to 5 lines on Snellen's chart from the baseline.

Potential role of Müller cells in the pathogenesis of macropsia associated with epiretinal membrane:a hypothesis revisited

Pathophysiological explanations for metamorphopsia associated with retinal pathologies generally focus on photoreceptor organization disruption. However, the retinal microarchitecture is complicated, and we hypothesize that other retinal cells may also be involved. Metamorphopsia has been widely studied in eyes with epiretinal membranes and we revisit the idea that Müller cell displacement causes retinal macropsia. A Pub Med query and related article search for the macula ultrastructure under normal and pathological conditions revealed an enormous amount of information, particularly ultrahigh definition optical coherence tomography and other retinal imaging modality studies. Findings of these imaging studies support our hypothesis that Müller cells, and not cone photoreceptors, are primarily responsible for macropsia in eyes with epiretinal membranes. More specifically, we conclude that displacement of Müller cell endfeet, and not photoreceptor cones, is a more likely the explanation for retinal macropsia associated with epiretinal membranes.

Inner limiting membrane peeling prevents secondary epiretinal membrane after vitrectomy for proliferative diabetic retinopathy

·AIM:To evaluate the role of internal limiting membrane(ILM)peeling in preventing secondary epiretinal membrane(ERM)formation in pars plana vitrectomy(PPV)for proliferative diabetic retinopathy(PDR).·METHODS:This retrospective study analyzed the medical records of patients who underwent PPV for PDR and were followed up for minimum 3 mo.ILM peeling was performed based on the intraoperative surgeons’judgments.ERM was assessed by optical coherence tomography photography.The relationship between ILM peeling and postoperative ERM was analyzed.·RESULTS:In total,212 eyes from 197 patients were included in this study.The incidence of secondary ERM in the ILM non-peeling group was significantly higher than that in the ILM peeling group(37.0%vs 14.0%;P<0.001).Multivariate logistical regression revealed that ILM peeling was highly associated with the prevention of secondary ERM development[odds ratio 0.38;95%confidence interval0.17-0.86;P<0.05].·CONCLUSION:ILM peeling during PPV for PDRs can effectively reduce the incidence of secondary ERM development and is worth consideration by vitreoretinal surgeons.

Reflectivity and thickness analysis of epiretinal membranes using spectral-domain optical coherence tomography

AIM：To compare thickness and reflectivity spectral domain optical coherence tomography（SD-OCT）findings in patients with idiopathic epiretinal membranes（ERMs）,before and after ERM peeling surgery,with normal controls.·METHODS：A retrospective study analyzing SD-OCTs of eyes with ERMs undergoing ERM peeling surgery by one surgeon from 2008 to 2010 and normal control eyes.SD-OCTs were analyzed using a customized algorithm to measure reflectivity and thickness.The relationship between the SD-OCT findings and best corrected visual acuity（BCVA）outcomes was also studied.·RESULTS：Thirty-four ERM eyes and 12 normal eyes were identified.Preoperative eyes had high reflectivity and thickness of the group of layers from the internal limiting membrane（ILM）to the retinal pigment epithelium（RPE）and the group of layers from the ILM to the external limiting membrane（ELM）.The values of reflectivity of these two groups of layers decreased postoperatively,but were still higher than normal eyes.In contrast,preoperative eyes had lower reflectivity of two10×15 pixel regions of interest（ROIs）incorporating：1）ELM＋outer nuclear layer（ONL）and 2）photoreceptor layer（PRL）＋RPE,compared to controls.The values of reflectivity of these ROIs increased postoperatively,but were still lower than normal controls.A larger improvement in BCVA postoperatively was correlated with a greater degree of abnormal preoperative reflectivity and thickness findings.·C ONCLUSION：Quantitative differences in reflectivity and thickness between preoperative,postoperative,and normal SD-OCTs allow assessment of changes in the retina secondary to ERM.Our study identified hyperreflective inner retina changes and hyporeflective outer retina changes in patients with ERMs.SD-OCT quantitative measures of reflectivity and/or thickness of specific groups of retinal layers and/or ROIs correlate with improvement in BCVA.

One-year follow-up evaluation of combined phacovitrectomy for idiopathic epiretinal membrane

AIM:To evaluate the therapeutic effect of combined phacovitrectomy with membrane peeling and intraocular lens(IOL)implantation in patients with severe idiopathic epiretinal membrane(iERM)and concurrent cataract.METHODS:A total of 34 eyes from 34 patients who underwent phacovitrectomy and epiretinal membrane(ERM)peeling at the First Affiliated Hospital of Zhejiang University between 2015 and 2017.The best-corrected visual acuity(BCVA)and central foveal thickness(CFT)were measured preoperatively and at 1,3,6 mo and 1 y postoperatively.Temporal changes and bivariate correlations of these parameters were analyzed.RESULTS:Mean logMAR BCVA improved and CFT decreased significantly(P<0.001)until 6 mo after surgery.Correlation analysis revealed a positive correlation between preoperative and postoperative logMAR BCVA(r=0.716,P<0.001 at 1 mo,r=0.417,P=0.014 at 3 mo,r=0.359,P=0.037 at 6 mo,and r=0.369,P=0.032 at 12 mo post-op respectively),but preoperative CFT was neither associated with postoperative CFT nor with postoperative logMAR BCVA.There was a positive correlation between CFT and logMAR BCVA at 1 mo(r=0.346,P=0.045),6 mo(r=0.347,P=0.045),and 12 mo(r=0.342,P=0.048)post-operatively.The intraand postoperative complications were relatively mild,and the incidences were generally low.CONCLUSION:For severe iERM patients with significant visual symptoms,combined phacovitrectomy with membrane peeling and IOL implantation is safe and effective in improving BCVA and decreasing CFT.Early surgery in selected patients may help preserving better visual function.

Description and surgical management of epiretinal membrane due to combined hamartoma of the retina and retinal pigment epithelium

Purpose:To outline the characteristics of Combined Hamartoma of the Retina and Retinal Pigmentation Epithelium(CHRRPE)and provide a comprehensive overview of surgical management of epiretinal membrane(ERM)caused by CHRRPE.Main text:CHRRPE is a rare ocular tumor.It clinically mimics other diseases such as retinoblastoma and choroidal melanoma.The present study reviewed the multimodal imaging of CHRRPE,highlighted the multimodal imaging modalities which are useful for revealing the unique features of CHRRPE and hence allowing physicians to confirm the diagnosis.Although most of CHRRPEs are benign harmatoma,progressive visual loss may occur because of the traction of the tumor and other complications.It is treated through surgical removal of the ERM caused by CHRRPE to free retina from the traction.Currently,there is no consensus on the surgical management of CHRRPE.Therefore,the current review was designed to explore the surgical management of ERM caused by CHRRPE and hence provide updated data on this subject.Conclusions:Multimodal imaging technologies,especially optical coherence tomography(OCT),significantly contributes to the diagnosis of CHRRPE and visual prognosis.Surgical management of CHRRPE through removal of ERM is beneficial in patients with worsening VA which is secondary to ERM which is associated with CHRRPE.However,the strategy is limited to patients with long-standing poor vision.However,earlier surgical therapy and subsequent postoperative amblyopia therapy can be explored for children of amblyogenic age.

Increased risk of postsurgical macular edema in high stage idiopathic epiretinal membranes

Purpose:To assess the rate of occurrence and the risk factors of postsurgical macular edema(PSME)in eyes with idiopathic epiretinal membrane(iERM)or full-thickness macular hole(FTMH).Methods:Retrospective longitudinal analysis of all subjects scheduled for vitrectomy with or without combined cataract surgery over a 6-month period.Electronic medical charts and imaging data were analyzed preoperatively and at 1,3 and 6 months after surgery.Results:From 101 patients diagnosed with iERM or FTMH,71 patients were eligible for the study.Forty-nine eyes with iERM(69.0%)and 22 eyes with FTMH(31.0%)underwent vitrectomy either isolated(31.0%)or combined with cataract extraction(69.0%).The overall rate of PSME was 26.7%,without differences between the two groups(P=0.9479).Combined cataract extraction did not affect the overall occurrence of PSME rate in both groups(P=0.9255 in FTMH and P=0.8658 in iERM).If grouped by stage,eyes with stage 4 iERM though disclosed an increased rate of PSME(57.1%)compared to lower(1 to 3)stages(14.3%,P=0.0021),particularly when combined with cataract surgery(71.4%vs.15.4%in stages≤3,P=0.0021).The PSME odds ratio for a stage 4 iERM is 8(95%CI:1.933-33.1;P=0.0041)compared to stages 3 and below.Conclusions:PSME remains a clinically relevant and frequent event after surgery for iERM and FTMH.Patients with stage 4 iERM have an 8-fold higher likelihood of developing PSME in a 6-month postsurgical period compared to iERM in 1-3 stages,especially when combined with cataract extraction.

A simple new technique for the induction of residual posterior vitreous cortex removal and membrane peeling

AIM:To describe a quick,cost-effective alternative to using a scraper to remove the residual posterior vitreous cortex and create an inner limiting membrane(ILM)flap during vitrectomy.METHODS:The surgical technique and a retrospective interventional single-center series of cases were described.A hook was made on the tip of a conventional syringe needle(outer diameter,0.6 mm;23 gauge)by bending the needle against a plate.We used this hook to remove the residual posterior vitreous cortex and create an ILM flap during vitrectomy.The efficacy and safety of using this instrument in ophthalmological procedures for a variety of vitreoretinal disorders were evaluated.RESULTS:The hook was effective for removing focal or diffuse residual posterior vitreous cortex in eyes with rhegmatogenous retinal detachment,proliferative diabetic retinopathy,and pathological myopia.It was also successfully used to make a free edge of the ILM and help strip the epiretinal membrane.There were no serious complications associated with using the hook in delicate ophthalmological procedures.CONCLUSION:The hook,made by bending a conventional needle,is a simple and cost-effective instrument for removing residual posterior vitreous vortex and to create epiretinal and ILM flaps during vitrectomy in eyes with various vitreoretinal diseases.

Prognostic factors of short-term outcomes of intravitreal ranibizumab in diabetic macular edema

AIM：To evaluate the prognostic factors for short-term visual and anatomical improvement of intravitreal ranibizumab（IVR） for diabetic macular edema（DME）.METHODS：Fifty-one eyes from 35 patients that received three consecutive monthly IVR for DME with moderate visual loss were retrospectively recruited; all cases had their baseline best-corrected visual acuity（BCVA） between 20/400 and 20/40. BCVA and central subfield thickness（CST） at baseline and month 3 were collected. Linear mixed models were used to evaluate the prognostic factors for visual and anatomical improvement at month 3.RESULTS：Younger age, poorer baseline BCVA and proliferative diabetic retinopathy（PDR） were correlated with better visual improvement at month 3（P=0.002, 0.0001 and 0.007, respectively）. Thicker CST and the presence of subretinal fluid at baseline were correlated with a greater reduction in CST（P〈0.0001 and P=0.018, respectively）. The presence of epiretinal membrane or previous posterior subtenon injection of triamcinolone acetonide（PSTA） were associated with a smaller reduction in CST（P=0.029 and 0.018, respectively）, but had no significant effects in visual improvement at month 3（P〉0.05 for both）.CONCLUSION：For eyes with DME and moderate visual loss, those with younger age, poorer baseline BCVA or PDR tend to have better visual improvement after three consecutive monthly IVR. Epiretinal membrane or previous PSTA result in less resolution of CST, but do not significantly affect visual improvement.

Importance of 3-D image reconstruction of spectraldomain OCT on outcome of grid laser photocoagulation for diffuse diabetic macular edema

AIM:To present the outcome of modified grid laser photocoagulation(GLP)in diffuse diabetic macular edema(DDME)in eyes without extrafoveal and/or vitreofoveal traction.METHODS:Inclusion criteria for the retrospective study were DDME eyes of patients with typeⅡdiabetes mellitus that had≥4 months of follow-up following GLP.Only one eye per patient was analyzed.Using 3-D spectral-domain optical coherence tomography(3-D SDOCT),eyes that had either extrafoveal or vitreofoveal traction,or had been previously treated by an intravitreal medication(s)were excluded.Treated DDME eyes were divided into 4 groups:A)"Classic"DDME that involved the central macula;B)edema did not involve the macular center;C)eyes associated with central epiretinal membrane(ERM);D)DDME that was associated with macular capillary dropout≥2 disc-diameter(DD).RESULTS:GLP outcome in 35 DDME eyes after 4-24(mean,13.1±6.9)months was as follows:Group A)18eyes with"classic"DDME.Following one or 2(mean,1.2)GLP treatments,best-corrected visual acuity(BCVA)improved by 1-2 Snellen lines in 44.4%(8/18)of eyes,and worsened by 1 line in 11.1%(2/18).Central macular thickness(CMT)improved by 7%-49%(mean,26.6%)in77.8%(14/18)of eyes.Causes of CMT worsening(n=4)were commonly explainable,predominantly(n=3)associated with emergence of extrafoveal traction,5-9months post-GLP.Group B)GLP(s)in DDME that did not involve the macular center(n=6)resulted in improved BCVA by 1-2 lines in 2 eyes.However,the central macula became involved in the edema process after the GLP in 3(50%)eyes,associated with an emergence of extrafoveal traction in one of these eyes 4months following the GLP.Group C)GLP failed in all 5eyes associated with central ERM.Group D)GLP was of partial benefit in 2 of 6 treated eyes with macular capillary dropout≥2DD.CONCLUSION:Eyes with DDME that involved the macular center were found to achieve favourable outcomes after GLP(s)during mid-term follow-up,unless complicated pre-GLP or post-GLP by vltreoretinal interface abnormalities,often extrafoveal traction or ERM,or by capillary dropout≥2DD.Prospective studies with larger cohorts are required.

Impact of OCT scan-patterns in identifying morphological features of lamellar macular holes and macular pseudoholes

AIM:To evaluate the impact of the optical coherence tomography(OCT)scan patterns on the detection of the features associated with lamellar macular hole(LMH)and macular pseudohole(MPH).METHODS:This is a retrospective analysis of 100 consecutive eyes with LMH(n=41)and MPH(n=59)having at least three of the following OCT features,which include mandatory criteria for the diagnosis of LMH and MPH:Epiretinal membrane,epiretinal proliferation,verticalization,intraretinal cystoid spaces,foveoschisis,irregular foveal contour,foveal cavity with undermined edges,and ellipsoid line disruption.Primary outcome measurement was the detection frequency of the features in three different OCT scan patterns:1)volume scan;2)six radial scans(R6);and 3)vertical and horizontal radial scans(R2).RESULTS:Of the total eight features,the maximal detection frequency was found as 4.45±1.45,4.35±1.47,and 3.70±1.59,by the volume,R6 and R2,respectively.R2 was inferior to the other patterns in detection of the total features(P<0.001),whereas R6 and volume patterns were found comparable(P=0.312).CONCLUSION:The physician should be aware that the selection of the OCT-scan pattern may influence the detection of mandatory morphological criteria for the diagnosis of LMH and MPH.

Retinoschisis and intravitreal ranibizumab treatment for myopic choroidal neovascularization

Background Intravitreal ranibizumab injection is effecitve on treating myopic CNVs,but it could be a risk factor for developing more severe retinoschisis in eyes with preexisted retinoschisis and epiretinal membrane.This study aimed to explore the incidence and features of retinoschisis after intravitreal ranibizumab injection for myopic choroidal neovascularization.Methods Eighty-three eyes of 81 patients with choroidal neovascularization secondary to pathologic myopia were treated with intravitreal ranibizumab injection.The best corrected visual acuity and optical coherence tomography （OCT） images were recorded at baseline and every month thereafter.Central retina thickness and maximal retina thickness were measured.The subjects were divided into three groups.Eleven eyes that had retinoschisis and epiretinal membrane were in group 1,six eyes that had simple epiretinal membrane were in group 2,and 66 eyes that had neither retinoschisis nor epiretinal membrane were in group 3.Six contralateral eyes in group 1 which had retinoschisis and epiretinal membrane but were not treated with intravitreal ranibizumab injection were set as the control group.Results Seven of the 11 eyes in group 1 developed more severe retinoschisis,the mean maximal retinal thickness increased from （380.28±90.13） to （467.00±70.20） μm （P 〈0.05）.The retinoschisis of all 6 eyes of the control group did not aggravate.Compared with the control group,the aggravation ratio of retinoschisis increased significantly （P 〈0.05）.No new onset of retinoschisis took place in group 2 and group 3.Conclusion Intravitreal ranibizumab injection may be a risk factor for aggravation of retinoschisis in eyes with preexisted retinoschisis and epiretinal membrane.