Retinal displacement after surgery for idiopathic macular hole

AIM:To review and summarize the mechanism hypothesis,influencing factors and possible consequences of macular retinal displacement after idiopathic macular hole(IMH)surgery.METHODS:PubMed and Web of Science database was searched for studies published before April 2023 on“Retinal displacement”,“Idiopathic macular holes”,and“Macular displacement”.RESULTS:Recently,more academics have begun to focus on retinal displacement following idiopathic macular holes.They found that internal limiting membrane(ILM)peeling was the main cause of inducing postoperative position shift in the macular region.Moreover,several studies have revealed that the macular hole itself,as well as ILM peeling method,will have an impact on the result.In addition,this phenomenon is related to postoperative changes in macular retinal thickness,cone outer segment tips line recovery,the occurrence of dissociated optic nerve fiber layer(DONFL)and the degree of metamorphopsia.CONCLUSION:As a subclinical phenomenon,the clinical significance of postoperative macular displacement cannot be underestimated as it may affect the recovery of anatomy and function.

Area and volume ratios for prediction of visual outcome in idiopathic macular hole

AIM： To predict the visual outcome in patients undergoing macular hole surgery by two novel three-dimensional morphological parameters on optical coherence tomography （OCT）： area ratio factor （ARF） and volume ratio factor （VRF）. METHODS： A clinical case series was conducted, including 54 eyes of 54 patients with an idiopathic macular hole （IMH）. Each patient had an OCT examination before and after surgery. Morphological parameters of the macular hole, such as minimum diameter, base diameter, and height were measured. Then, the macular hole index （Mill）, tractional hole index （THI）, and hole form factor （HFF） were calculated. Meanwhile, novel postoperative macular hole （MH） factors, ARF and VRF were calculated by three-dimensional morphology. Bivariate correlations were performed to acquire asymptotic significance values between the steady best corrected visual acuity （BCVA） after surgery and 2D/3D arguments of MH by the Pearson method with two-tailed test. All significant factors were analyzed by the receiver operating characteristic （ROC） curve analysis of SPSS software which were responsible for vision recovery. ROC curves analyses were performed to further discuss the different parameters on the prediction of visual outcome. RESULTS： The mean and standard deviation values of patients＇ age, symptoms duration, and follow-up time were 64.8＋8.9y （range： 28-81）, 18.6＋11.5d （range： 2-60）, and 11.4＋0.4mo （range： 6-24）, respectively. Steady-post-BCVA analyzed with bivariate correlations was found to be significantly correlated with base diameter （r＇0.521, P〈0.001）, minimum diameter （r=0.514, P〈0.001）, MHI （r -0.531, P〈0.001）, THI （r=-0.386, P=-0.004）, HFF （r=-0.508, P〈0.001）, and ARF （r=-0.532, P〈0.001）. Other characteristic parameters such as age, duration of surgery, height, diameter hole index, and VRF were not statistically significant with steady-post-BCVA. According to area under the curve （AUC） values, values of ARF, MHI, HFF, minimum diameter, THI, and base diameter are 0.806, 0.772, 0.750, 0.705, 0.690, and 0.686, respectively. However, Steady-post-BCVA analysis with bivariate correlations for VRF was no statistical significance. Results of ROC curve analysis indicated that the MHI value, HFF, and ARF was greater than 0.427, 1.027 and 1.558 respectively which could correlate with better visual acuity. CONCLUSION： Compared with MHI and HFF, ARF could effectively express three-dimensional characteristics of macular hole and achieve better sensitivity and specificity. Thus, ARF could be the most effective parameter to predict the visual outcome in macular hole surgery.

Predicting anatomical results of surgical treatment of idiopathic macular hole

AIM： To determine the parameters most informative in predicting the anatomical results of surgical treatment of idiopathic full-thickness macular hole （IMH）. METHODS： One hundred and sixty-two consecutive patients （170 eyes） after primary operation for IMH were enrolled. Outcomes were classified as anatomical success when both IMH closure and restoration of the outer retinal structure were achieved. ＂Prospective＂ group included 108 patients （115 eyes） followed with optical coherence tomography （OCT） and microperimetry for ly after surgery. Potential prognostic criteria, except microperimetry data, were tested in ＂retrospective＂ group （54 patients, 55 eyes）. Prognostic value of each parameter was determined using receiver operating characteristic （ROC） analysis. Combined predictive power of the best prognostic parameters was tested with the use of linear discriminant analysis. RESULTS： IMH closure was achieved in 106 eyes （92%） in the prospective group and 49 eyes （89%） in the retrospective group. Despite anatomical closure, the outer retinal structure was not restored in two eyes in the first group and in one eye in the second group. Preoperative central subfield retinal thickness demonstrated the best discriminatory capability between eyes with anatomical success and failure： area under the ROC-curve （AUC） 0.938 （95% Ch 0.881-0.995）, sensitivity 64% at fixed specificity 95% （cut-off value 300um） in the prospective group; sensitivity 57% and specificity 90% in the retrospective group. Other continuous parameters except tractional hole index （AUC： 0.796, 95% Ch 0.591- 1.000） had significantly lower AUCs （P〈0.05）. The best combination of the parameters, established by discriminant analysis in the prospective group, could not confirm its predictive value in the retrospective group. CONCLUSION： Preoperative central subfield retinal thickness is a strong and probably the best predictor of anatomical results of IMH surgical treatment.

Visual function and vision-related quality of life after vitrectomy for idiopathic macular hole: a 12mo followup study

· AIM: To investigate the visual function and the relationship with vision-related quality of life(VRQOL)after macular hole repair surgery.· METHODS: Prospective case series. Thirty-six consecutive eyes in 36 patients who underwent pars plana vitrectomy(PPV) and internal limiting membrane(ILM) peeling were included. The 25-item National Eye Institute Visual Function Questionnaire(VFQ-25) was answered by the participants before and 3 and 12 mo after operation. Follow-up visits examinations included best-corrected visual acuity(BCVA), clinical examination,and central macular thickness(CMT) measured by optical coherence tomography(OCT).·RESULTS: Macular-hole closure was achieved in 35 of36 eyes(97.2%). At baseline and months 3 and 12, the log MAR BCVAs(mean±SD) were 1.15±0.47, 0.68±0.53(P 【0.0001 versus baseline), and 0.55 ±0.49(P 【0.001 versus baseline, P =0.273 versus month 3), respectively; the CMTs(μm) were 330 ±81, 244 ±62(P 【0.001 versus baseline), and 225±58(P 【0.001 versus baseline, P =0.222 versus month 3), respectively; the median preoperative VFQ-25 composite score of 73.50(63.92-81.13) increased postoperatively to 85.50(80.04-89.63) at 3mo(P 【0.001)and 86.73(82.50-89.63) at 12mo(P 【0.001) respectively.The improved BCVA was correlated with improvements in five subscales(r =-0.605 to-0.336, P 【0.001 to P =0.046) at 12 mo.· CONCLUSION: PPV with ILM peeling improved anatomic outcome, visual function, and VRQOL. Theimproved BCVA was an important factor related to the improved VRQOL.

The macular microstructure repair and predictive factors of surgical outcomes after vitrectomy for idiopathic macular hole

To evaluate the macular microstructure repair and explore the factors related to those changes and visual improvement after vitrectomy for idiopathic macular hole(IMH). Totally 19 eyes of 18 IMH patients who underwent macular hole(MH) surgery were evaluated with bestcorrected visual acuity(BCVA) and spectral-domain optical coherence tomography(SD-OCT) images. All 19 eyes closed at 6 mo postoperatively. BCVA was observed gradually improved(P<0.001), with subretinal fluid(SRF) gradually absorbed(P=0.021) and the rate of external limiting membrane(ELM) defects gradually decreased(P=0.011) with follow-up time. Poorer postoperative logMAR BCVA correlated with larger MH minimum diameter(P<0.001), larger MH basal diameter(P=0.008), longer symptom duration(P=0.002) and poorer preoperative logMAR BCVA(P=0.010). More improvement in BCVA correlated only with poorer preoperative in logMAR BCVA(P=0.002). The earlier reconstruction of ELM was associated with smaller MH basal diameter(P=0.022) and shorter symptom duration(P=0.008). In conclusion, smaller basal diameter of MH and shorter symptom duration were key factors in earlier reconstruction of ELM.

The optic nerve head perfusion and its correlation with the macular blood perfusion in unilateral idiopathic macular hole： an optical coherence tomography angiography study

AIM： To compare the optic nerve head （ONH） perfusion in both eyes of unilateral idiopathic macular hole （IMH） with normal control group by using optical coherence tomography angiography （OCTA） and investigate its correlationship with the macular blood perfusion. METHODS： We performed a prospective and cross- sectional study that included 19 patients with full-thickness unilateral IMH and 24 age- and sex-matched controls. All participants received OCTA test. The ONH perfusion was evaluated by the regions of peripapillary and whole en face （the sum of peripapillary and optic disc）. The potential correlationship between ONH and parafovea were implied. All the data were performed using the nonparametric test. RESULTS： The mean values of ONH presented that normal control 〉IMH 〉unaffected eyes. A statistical variation was found between three groups in the region of temporal （P=-0.007）, Vessel density notablely decreased on the layers of superficial, deep and choroid of parafovea region in IMH group. The correlative coefficients showed that respectively whole en face and deep retina： r=0.528, peripapillary and deep retina： r=0.525, whole en face and choriocapillaries： r=0.569, peripapillary and choriocapillaries： t=0.504. CONCLUSION： Our study demonstrate a reduced ONH vessel density in both eyes of IMH patients and the vessel density of ONH in IMH eyes are positively correlated with both the retina capillary and choriocapillary in parafoveal. The reduction of vessel densities may indicate the hypoperfusion in IMH eyes,

Refractive outcomes after vitrectomy combined with phacoemulsification of idiopathic macular holes

AIM:To report the refractive outcomes after vitrectomy combined with phacoemulsification and intraocular lens(IOL)implantation(phaco-vitrectomy)in idiopathic macular holes(IMH).METHODS:A total of 56 eyes with IMH(IMH group)that underwent phaco-vitrectomy and 44 eyes with age-related cataract(ARC group)that underwent cataract surgery were retrospectively reviewed.The best corrective visual acuity(BCVA),predicted refractive error(PRE),actual refractive error(ARE),axial length(AL),were measured in both groups before and 6 mo after operation.The power calculation of IOL and the predicted refractive error(PRE)were calculated according to the SRK/T formula.The difference of PRE and ARE between the two groups were compared and analyzed.RESULTS:In the IMH group,the diameters of macular holes were 271.73±75.85μm,the closure rate was 100%.The pre-and post-operative BCVA were 0.80±0.35 and 0.40±0.35 log MAR.The PRE of A-ultrasound and IOL Master in the IMH group was-0.27±0.25 and 0.10±0.66 D.The postoperative mean absolute prediction error(MAE)was observed to be 0.58±0.65 and 0.53±0.37 D in the IOL Master and A-ultrasound(P=0.758).The PRE and ARE of the IMH group were 0.10±0.66 D and-0.19±0.64 D(P=0.102).The PRE and ARE of the ARC group was-0.43±0.95 and-0.31±0.93 D(P=0.383).The difference between PRE and ARE was-0.33±0.81 and 0.09±0.64 D in the IMH and ARC groups(P=0.021).The proportion of myopic shift was 67.9%in the IMH group and 27.3%in the ARC group(P=0.004).CONCLUSION:The myopic shift can be observed in patients with IMH after phaco-vitrectomy.

Internal limiting membrane peeling with different dyes in the surgery of idiopathic macular hole: a systematic review of literature and network Meta-analysis

AIM: To evaluate the effect of internal limiting membrane(ILM) peeling with indocyanine green(ICG), brilliant blue G(BBG), triamcinolone acetonide(TA), trypan blue(TB), or without dye for the treatment of idiopathic macular hole(IMH). METHODS: A search was conducted using Pub Med, EMBASE, and CENTRAL(Cochrane Central Register of Controlled Trials) for related studies published before October 2018. RESULTS: A total of 29 studies and 2514 eyes were included in this network Meta-analysis. For IMH closure, the rank from the best to the worse treatment was: BBG, TB, TA, ICG, and no dye. There was a significant difference in postoperative IMH closure rate between BBG and no dye. The rank of the best to the worse treatment to improve visual acuity was: BBG, TB, no dye, TA, and ICG. The improvement rate of visual acuity after using BBG was significantly higher than ICG. The improvement rate of visual acuity was more favorable with TB than ICG, TA, and no dye. CONCLUSION: BBG can contribute to better anatomical and functional outcomes compared to other dyes for ILM peeling in patients with IMH. The results show that the best treatment of ILM peeling with dyes is BBG.

Displacement of the retina after idiopathic macular hole surgery with different internal limiting membrane peeling patterns

AIM:To explore retinal displacement after surgical treatment for idiopathic macular hole(IMH)with different internal limiting membrane(ILM)peeling patterns.METHODS:Totally 22 eyes from 20 patients with IMH were randomly allocated into two groups,N-T group(11 eyes)and T-N group(11 eyes).For patients in N-T group,ILM was peeled off from nasal to temporal retina.For patients in T-N group,ILM was peeled off from temporal to nasal retina.Preoperative,postoperative 1,3,and 6 mo,autofluorescence fundus images were collected for manual measurement of distances of fixed nasal(N),temporal(T),superior(S),and inferior(I)retinal points(bifurcation or crossing of retinal vessels)around the macula to the optic disc(OD).These were respectively defined as N-OD,T-OD,S-OD,and I-OD.The retinal displacement,macular holeclosure rate,and best corrected visual acuity(BCVA)were compared between the two groups after surgery.RESULTS:At postoperative 1,3,and 6 mo,the macula slipped toward the OD,manifested by the decreased T-OD,N-OD,S-OD,and I-OD(P<0.05).No significant difference was found in the T-OD,N-OD,S-OD,and I-OD between N-T group and T-N group.IMH closure rate was 100%both in N-T group and T-N group.There was no significant difference in BCVA between two groups(P<0.05).CONCLUSION:The macula slips toward the OD after successful macular hole surgery.The two different ILM peeling pattern show similar visual outcome and retinal displacement,which means ILM peeling directions are not the influencing factor of postoperative retinal displacement.

Comparison of outcomes of idiopathic macular holes treated by vitrectomy with air or silicone oil tamponade based on the hole size

AIM:To compare the efficacy of vitrectomy combined with air or silicone oil in the treatment of idiopathic macular hole(IMH).METHODS:According to the results of high-definition optical coherence tomography(HD-OCT),75 cases(75 eyes)of IMH in stage II-IV(Gass stage)in the General Hospital of Chinese PLA from January 2017 to December 2019 were collected for this retrospective study.The best corrected visual acuity(BCVA)and minimum diameter of IMH(MMHD)were measured.Eyes underwent vitrectomy combined with internal limiting membrane peeling operation,and were divided into disinfection air group(30 eyes)and silicone oil group(45 eyes)according to the intraocular tamponade.For MMHD≤400μm(MMHD1),there were 23 eyes in air group and 16 eyes in silicone oil group.For MMHD2>400μm(MMHD2),there were 7 eyes in air group and 29 eyes in silicone oil group.One month after surgery,the closure rates of IMH and BCVA were compared and analyzed.According to HD-OCT,the closure shape was graded with A(bridge closure)and B(good closure).RESULTS:The closure rates of air group and silicone oil group were 86.67%and 95.56%respectively with no significant difference(P>0.05);For MMHD1,those of air group and silicone oil group were 95.65%and 100%respectively with no significant difference(P>0.05);For MMHD2,those of air group and silicone oil group were 57.14%and 93.10%respectively,and those of the silicone oil group were higher than the air group(P<0.05).There was no significant difference in the closure shape grade between MMHD1 air group and silicone oil group(P>0.05).The proportion of Grade B in MMHD2 silicone oil group was higher than that in the air group(P<0.05).BCVA of each group after operation was better than that before operation,and there was no significant difference between air group and silicone oil group.While among them,MMHD1 air group was better than silicone oil group(P<0.05),and there was no significant difference between MMHD2 air group and silicone oil group(P>0.05).CONCLUSION:For smaller IMH(≤400μm),the efficacy of vitrectomy combined with air should be considered better than silicone oil;for larger IMH(>400μm),the efficacy of silicone oil may be better than air.

Negative effects of enlarging internal limiting membrane peeling for idiopathic macular hole surgery

AIM: To observe the effects of the different extents of internal limiting membrane(ILM) peeling on the surgical success and anatomical and functional outcomes of idiopathic macular hole(IMH).METHODS: In this retrospective cohort study, 36 patients were reviewed and divided into two groups according to the extent of ILM peeling: group A(18 patients), with the peeling area within one-half of the optic disc macular distance as the radius;group B(18 patients), with the peeling area larger than that of group A but did not exceed the optic disc macular distance as the radius. The main outcomes included the best corrected visual acuity(BCVA), light-adaptive electroretinography, macular hole(MH) closure rate, central macular thickness(CMT), retinal nerve fiber layer(RNFL) and ganglion cell complex(GCC) thickness [nine regions based on the Early Treatment of Diabetic Retinopathy Study(ETDRS) ring] before and 1, 3, and 6mo after surgery.RESULTS: The closure rate was 94.4%(17/18) both in groups A and B. The BCVA in both groups improved significantly compared with the preoperative values, but there was no difference between the two groups. The b-wave amplitude of the electroretinogram analysis was significantly improved in both groups compared to that of the preoperative period, with a greater increase in group A than in group B at 6mo(P=0.017). The CMT in both groups gradually decreased after surgery, and there was no difference between the two groups. The RNFL thickness of the temporal outer ring region in group B was significantly lower than that in group A at 3 and 6mo after surgery(P=0.010, 0.032). The GCC thickness of the temporal outer ring region in group B was significantly lower than that in group A at 6mo after surgery(P=0.038).CONCLUSION: Enlarging the extent of ILM peeling doesn’t affect the IMH closure rate and visual acuity recovery, but the greater the extent of peeling, the greater the damage to the inner retinal structures.

Retinal displacement after closure of idiopathic macular hole

Objective: To study the foveal displacement during the closure of idiopathic macular holes(MHs).Methods: Thirty-seven idiopathic MH patients treated by pars plana vitrectomy and internal limiting membrane peeling were studied prospectively.Locations of MH center and foveal pit were measured by optic coherence tomography.Retinal displacement was observed using confocal scanning laser ophthalmoscopy.Results: A total of 40 eyes were included in this study and MHs were closed in 37 eyes(92.5%).The confocal scanning laser ophthalmoscopy showed that all of the retinal capillaries in the superior, inferior, nasal and temporal sides of the MHs moved toward the optic nerve head(ONH).The optic coherence tomography results showed that the mean nasal displacements of foveal pits were(102.9±61.2),(109.6±53.1), and(137.0±52.0) μm at 3, 6 and 12 months, respectively.And the mean vertical displacements were(55.9±49.4),(61.4±57.8) and(67.8±54.3) μm, respectively.Post-operative foveal pits were located in the nasal side of the MH centers.The extension of retina and nasal to the MH were in opposite directions: the nasal hole margin moved toward the MH, but the retina located closer to the ONH moved toward the ONH.The fellow eyes of three patients developed into idiopathic MH during the follow-up period and operations were performed for all of the three patients.Conclusion: Our results showed that center of macula does not move when an idiopathic MH develops, but it moves toward ONH during closure of hole; thus, new fovea is in nasal side of original fovea.

The Preliminary Report of Pathological Changes of Epiretinal Membranes and Internal Limiting Membrane Removed during Idiopathic Macular Hole Surgery

Purpose:To investigate the pathological changes of epiretinal membranes(ERM)and internal limiting membrane (ILM) removed during idiopathic macular hole surgery.Methods:Ten consecutive patients with a unilateral idiopathic macular hole underwent pars plana vitrectomy(PPV) with the surgical removal of the ERMs overlying the hole and ILM surrounding the hole. The pathological features of the excised tissues were examined under the microscope. Results:According to the morphological changes, four ERMs showed cellular elements which looked like glia cells, macrophages, plasma cells, lymphocytes and fibroblast cells. Two of the ILM appeared as transparent membranes without cellular elements. The other eight ILM showed cellular elements on the transparent membranes.Conclusion: Our study supports the hypothesis that the tangential traction of vitreous and proliferative cellular elements on the inner surface of ILM causes idiopathic macular holes. Removal of the posterior cortical vitreous, ILM and proliferative cellular tissue is a valid treatment for IMH.

Optical coherence tomography's diagnostic value in evaluating surgical impact on idiopathic macular hole

Objective To identify the characteristics of and evaluate surgical impact on idiopathic macular hole (IMH) by using an optical coherence tomography (OCT) scanner. Methods Sixty-five cases (70 eyes) experiencing IMH were examined using OCT, then graded by their clinical characteristics. Nineteen cases (19 eyes) were scanned and measured using OCT before and after surgery.Results Of the 70 eyes,the number of stage Ⅰ-Ⅳ macular holes were 11, 12, 36 and 11, respectively. For stage Ⅰ holes, the OCT images revealed flattened or nonexistent fovea and minimally reflective space within or beneath the neurosensory retina; stage Ⅱ holes appeared to be full-sized with attached operculum and surrounding edema; stage Ⅲ holes were also full-sized with surrounding edema; finally, stage Ⅳ holes were full-sized and completely separated the posterior hyaloid membrane from the retina. Through quantitative measurements, OCT determined that the values for mean hole diameter, mean halo diameter and mean thickness of the hole's edge were reduced from 570.95±265.59 to 337.05±335.95 μm, 1043.53±278.8 to 695.00±483.00 μm and 389.78±60.58 to 298.78±109.80 μm, respectively in 19 IMH cases after surgery. In 17 eyes, the holes or halos eventually closed or were reduced in size, or the edges of the holes thinned out. The anatomic successful rate of the surgery was 89%.Conclusion OCT can exhibit the characteristics of IMH and measure the diameter of holes quantitatively. This method can also judge the surgical impacts of IMH objectively, accurately and effectively.

The Electrophysiology in Idiopathic Senile Macular Hole

Of 12 patients with idiopathic senile full- thickness macular hole, 3 had bilateral involvement, 9 had monocular macular hole. Flash ERG and pattern VEP were performed in the bilateral eyes of all patients. The abnormal rate of the pattern VEP was 93.3% when we used 15' checkboard stimulus, the changes of the VEP appeared as delayed latencies, reduced amplitudes or malformation of P100. The abnormal rate of the flash ERG was 53.3%, showing primary characteristics of reduced amplitudes of cone response b...

Biomaterial engineering strategies for modeling the Bruch's membrane in age-related macular degeneration

Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular degeneration.Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying choriocapillaris.The Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie r.In the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials.This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems.Then,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.

Regulatory factors of Nrf2 in age-related macular degeneration pathogenesis

Age-related macular degeneration(AMD)is a complicated disease that causes irreversible visual impairment.Increasing evidences pointed retinal pigment epithelia(RPE)cells as the decisive cell involved in the progress of AMD,and the function of anti-oxidant capacity of PRE plays a fundamental physiological role.Nuclear factor erythroid 2 related factor 2(Nrf2)is a significant transcription factor in the cellular anti-oxidant system as it regulates the expression of multiple anti-oxidative genes.Its functions of protecting RPE cells against oxidative stress(OS)and ensuing physiological changes,including inflammation,mitochondrial damage and autophagy dysregulation,have already been elucidated.Understanding the roles of upstream regulators of Nrf2 could provide further insight to the OS-mediated AMD pathogenesis.For the first time,this review summarized the reported upstream regulators of Nrf2 in AMD pathogenesis,including proteins and miRNAs,and their underlying molecular mechanisms,which may help to find potential targets via regulating the Nrf2 pathway in the future research and further discuss the existing Nrf2 regulators proved to be beneficial in preventing AMD.

RNA-sequencing expression profile and functional analysis of retinal pigment epithelium in atrophic age-related macular degeneration

The retinal pigment epithelium(RPE)is fundamental to sustaining retinal homeostasis.RPE abnormality leads to visual defects and blindness,including age-related macular degeneration(AMD).Although breakthroughs have been made in the treatment of neovascular AMD,effective intervention for atrophic AMD is largely absent.The adequate knowledge of RPE pathology is hindered by a lack of the patients'RPE datasets,especially at the single-cell resolution.In the current study,we delved into a large-scale single-cell resource of AMD donors,in which RPE cells were occupied in a substantial proportion.Bulk RNA-seq datasets of atrophic AMD were integrated to extract molecular characteristics of RPE in the pathogenesis of atrophic AMD.Both in vivo and in vitro models revealed that carboxypeptidase X,M14 family member 2(CPXM2),was specifically expressed in the RPE cells of atrophic AMD,which might be induced by oxidative stress and involved in the epithelial-mesenchymal transition of RPE cells.Additionally,silencing of CPXM2 inhibited the mesenchymal phenotype of RPE cells in an oxidative stress cell model.Thus,our results demonstrated that CPXM2 played a crucial role in regulating atrophic AMD and might serve as a potential therapeutic target for atrophic AMD.

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.