Evaluation of combined epiretinal membrane removal with intravitreal triamcinolone injection utilizing ectopic inner foveal layer staging scheme.

OBJECTIVE: To investigate the macular morphological and visual outcomes of combined idiopathic epiretinal membrane (iERM) removal with triamcinolone acetonide (TA) injection based on consideration of the ectopic inner foveal layer (EIFL) staging scheme. METHODS: Retrospective case-control study. The clinical data of 84 eyes of 84 patients who underwent vitrectomy for iERM between 2018 and 2022 were reviewed. The enrolled subjects were divided into the TA and non-TA groups. Fifty-one eyes received intravitreal TA injection following vitrectomy and ERM peeling (TA group), and 33 were only treated by standard vitrectomy and ERM peeling (non-TA group). Preoperative and postoperative EIFL stages, central foveal thickness (CFT), and best-corrected visual acuity (BCVA) were compared between both groups. RESULTS: After a mean follow-up of 7.69 ± 3.68 months, both groups exhibited significant improvement in EIFL stages (P < 0.01), with no discernible advantage observed in the TA group. The TA and non-TA groups demonstrated improvement in the EIFL stages in 56.86 and 63.64% of eyes, respectively (P = 0.43). The CFT and BCVA significantly improved in both groups at the final visit (P < 0.01). However, CFT in the non-TA group displayed a more significant reduction during the follow-up (P < 0.03). Subgroup analysis revealed no significant differences in postoperative CFT and BCVA between the two groups in cases with or without continuous EIFL (P > 0.10). CONCLUSION: Our findings indicate that combined intravitreal TA injection following ERM removal conferred no significant benefits in alleviating macular thickening or improving visual acuity in iERM.

Effect of topical bromfenac on intraretinal cystoid lesion in simultaneous cataract and idiopathic epiretinal membrane surgery.

PURPOSE: To investigate the effect of topical nonsteroidal anti-inflammatory drugs (NSAIDs,) bromfenac on the intraretinal cystic lesions (IRC) when performing simultaneous cataract and idiopathic epiretinal membrane (iERM) surgery. METHODS: This study included patients with iERM who had been followed up for 6 months after vitrectomy, membrane removal, and concurrent cataract surgery. Eyes were treated with topical bromfenac or not. The baseline fluorescein angiography (FA) was obtained to assess the microvascular leakage (ML). Structural changes of macula, including IRC and central macular thickness (CMT) were assessed using optical coherence tomography (OCT). The main outcome measures were changes in IRCs and best-corrected visual acuity (BCVA) regarding FA findings. RESULTS: One hundred eighteen eyes were included. IRC and ML were observed in 51 eyes (43.2%) and 63 eyes (53.4%), respectively. The IRC did not show any association with the ML. Of total, 29 eyes (24.6%) were treated with topical bromfenac (Group A). Compared to Group B, topical bromfenac did not show beneficial effects in aspect of preventions for the newly developed IRC and treatment for pre-existed IRC. Whether the ML existed or not, topical bromfenac did not show any different effect on the changes in BCVA and IRC. CONCLUSION: When performing simultaneous cataract and ERM surgery, topical NSAIDs, bromfenac did not show beneficial effects on the preventions and treatment of IRC in both eyes with and without the ML.

Changes in optical coherence tomography biomarkers in eyes with advanced idiopathic epiretinal membrane treated with dexamethasone implantation.

PURPOSE: To investigate the effects of vitrectomy and intravitreal dexamethasone (DEX) implantation on retinal biomarkers in patients with advanced idiopathic epiretinal membrane (IERM) and to evaluate this treatment's anatomical and functional outcomes. METHODS: This retrospective study included 41 patients with advanced IERM who underwent vitrectomy and were divided into a pars plana vitrectomy (PPV) group (20 eyes) and a dexamethasone (DEX) group (21 eyes) based on intravitreal DEX implantation. We collected data on best-corrected visual acuity (BCVA), central macular thickness (CMT), disorganization of the retinal inner layers (DRIL), subretinal fluid, intraretinal cystoid changes (IRC), integrity of the inner-outer segment layer, and intraocular pressure. RESULTS: BCVA improved significantly in both groups; the DEX group had a higher visual acuity gain at 1 and 6 months (P = 0.002 and 0.023, respectively). Postoperative CMT gradually decreased in both groups, with the DEX group showing a greater decrease at 1 and 6 months (P = 0.009 and 0.033, respectively). Six months after surgery, the DRIL and IRC grades in the DEX group were significantly improved compared to those in the PPV group (P = 0.037 and 0.038, respectively). Multivariate regression analyses revealed that patients with intraoperative DEX implants were more likely to have a significant CMT reduction (≥ 100 µm) from baseline (odds ratio (OR), 9.44; 95% confidence intervals (CI), 1.58-56.56; P = 0.014) at 6 months and less likely to exhibit DRIL at 6 months postoperatively (OR, 0.08; 95% CI, 0.01-0.68; P = 0.021). CONCLUSION: Vitrectomy combined with intravitreal DEX implantation facilitates the recovery of postoperative visual acuity and improvement of anatomical outcomes in patients with advanced IERM, effectively reducing CMT and improving DRIL.

Increased serum cystatin C levels in patients with idiopathic epiretinal membrane.

CLINICAL RELEVANCE: Increased serum cystatin C may play a role in the pathogenesis of idiopathic epiretinal membrane (IERM). Physicians should be aware of this relationship and should refer patients to the ophthalmology clinic for screening. BACKGROUND: To evaluate the serum cystatin C level in patients with IERM, and its associations with visual acuity. METHODS: Sixty-eight patients with IERM and sixty-nine controls were enrolled in this cross-sectional study. Based on the results of optical coherence tomography, patients with IERM were divided into four stages (I, II, III and IV). Serum cystatin C was measured in all participants. Serum cystatin C levels were compared between the control group and IERM group and between the IERM group with different optical coherence tomography stages. Multiple linear regression was used to evaluate the relationship between serum cystatin C and IERM stages and best corrected visual acuity. RESULTS: Serum cystatin C level was higher in the IERM group than in the control group (P < 0.001). There were statistically significant differences in serum cystatin C among different stages of IERM (PI vs II = 0.011, PI vs IV < 0.001 and PIII vs IV = 0.040, respectively). There were significant differences in best corrected visual acuity among different stages of IERM (PI vs III = 0.018, PI vs IV < 0.001, PII vs IV < 0.001 and PIII vs IV < 0.001, respectively). Regression analysis showed a positive correlation between serum cystatin C and best corrected visual acuity (t = 2.238 P = 0.029). The cut-off value of receiver operation characteristic curve of serum cystatin C for IERM was 0.775. CONCLUSION: This study revealed that serum cystatin C may be involved in the pathogenesis of IERM and can predict its occurrence. Elevated serum cystatin C appears to be associated with the severity of the disease and relatively poor vision acuity in IERM patients.

Research progress of optical coherence tomography and optical coherence tomography angiography in the prediction of postoperative visual acuity in patients with idiopathic epiretinal membrane / 国际眼科杂志(Guoji Yanke Zazhi)

Idiopathic epiretinal membrane(IERM)is a kind of epiretinal membrane without any other known ocular conditions, which occurs mostly in the middle-aged and elderly people over the age of 50. As IERM worsens, the structure and function of the retina in the macular region are altered, leading to symptoms like reduced vision and metamorphopsia. The pathogenesis of IERM remains unclear, and surgery is the primary treatment option. However, there is no consensus on the best time to have surgery, and there are differences in how well patients recover their vision following surgery. Optical coherence tomography(OCT)and OCT angiography(OCTA), as non-invasive and rapid diagnostic tools to observe retinal microstructure and blood flow changes in the macula, have been extensively utilized in clinical settings. The use of OCT and OCTA parameters to predict postoperative visual acuity has emerged as a hot topic in IERM research. This article provides a comprehensive review of current research on the correlation between various OCT and OCTA parameters and the prediction of postoperative visual acuity in IERM, aiming to assist clinicians in determining the optimal timing for surgery and balancing the benefits and risks involved.

Ultrastructural Details of Epiretinal Membrane Foveoschisis.

INTRODUCTION: The aim of this study was to describe differences in the vitreomacular interface (VMI) in idiopathic epiretinal membrane (ERM) foveoschisis compared to macular pseudohole (MPH) and lamellar macular hole (LMH). METHODS: We analysed surgically excised epiretinal material and internal limiting membrane (ILM) specimens obtained from 16 eyes of 16 patients with ERM foveoschisis (6 eyes), MPH (5 eyes), and LMH (5 eyes) during standard pars plana vitrectomy (PPV) with membrane peeling. The three entities were classified according to the newly introduced optical coherence tomography (OCT) terminology. Transmission electron microscopy (TEM) was used to describe the ultrastructural features. RESULTS: We found fibrocellular epiretinal tissues in all samples analysed. However, the cell and collagen composition of the VMI differed between groups. Eyes with ERM foveoschisis were characterized by a higher number of cells, multilayered membranes, and thick strands of vitreous collagen embedding the major cell types of myofibroblasts compared to MPH. Eyes with MPH also showed a predominance of myofibroblasts, but these were located directly on the ILM with no collagen between the cells and the ILM. Eyes with LMH showed a thick, multilayered epiretinal proliferation consisting mainly of non-tractional glial cells, corresponding to hypodense epiretinal proliferation on OCT. Eyes with ERM foveoschisis and MPH were more likely to have incomplete PVD compared to LMH in terms of posterior hyaloid status. DISCUSSION/CONCLUSION: Tractional ERMs in eyes with ERM foveoschisis and MPH differ in their ultrastructure. The main difference is in the amount and topographical distribution of vitreous collagen. However, the epiretinal cell types are predominantly myofibroblasts in both entities. This highlights the importance of distinguishing ERM foveoschisis from both MPH and LMH in terms of pathogenesis and surgical peeling procedures.

Correlation between Anatomical and Functional Outcomes in Patients with Idiopathic Epiretinal Membrane after Vitrectomy.

BACKGROUND: Idiopathic epiretinal membrane (iERM) is a common disorder of the vitreomacular interface characterized by decreased visual acuity and metamorphopsia. This study aimed to analyze the association between the anatomical change of the retina and functional outcomes in iERM patients so as to derive the prognostic factors of visual acuity (VA) and metamorphopsia. METHODS: Forty-five patients (one eye per patient; 45 eyes in total) who underwent pars plana vitrectomy and membrane peeling for iERM by a single surgeon were enrolled in this retrospective study. The results on best-corrected visual acuity (BCVA) and metamorphopsia as well as retinal images were obtained before the surgery and 1, 3, 6 months after the surgery. The BCVA and retinal microstructure, including central retinal thickness (CRT), ganglion cell layer (GCL) thickness, inner nuclear layer (INL) and outer nuclear layer + outer plexiform layer (ONL+OPL), and continuity of photoreceptor inner/outer segment (IS/OS) junction before and after iERM surgery were compared using paired samples t-test (continuous variables) or Chi-square test (categorical variables). Multiple regression analysis was carried out to explore the association among BCVA, M-score, and the parameters derived from optical coherence tomography. RESULTS: Compared with preoperative data, a significant improvement in BCVA was observed 1, 3, and 6 months postoperatively (t = 5.37, p < 0.0001; t = 7.29, p < 0.0001; t = 6.44, p < 0.0001 for 1, 3, and 6 months postoperatively, respectively), whereas the M-score only decreased significantly 3 and 6 months after the surgery (t = 2.36, p = 0.02; t = 5.00, p < 0.0001, respectively). In comparison with the baseline, the CRT, INL, and ONL+OPL thickness showed a significant decrease at each postoperative follow-up time, and GCL thickness (t = 3.86, p = 0.0002) and IS/OS disruption ratio (χ2 = 4.86, p = 0.027) were markedly reduced only 6 months postoperatively. Six-month postoperative BCVA was considerably associated with preoperative CRT and ONL+OPL thickness, as well as postoperative CRT, ONL+OPL thickness, and severity of IS/OS disruption. Moreover, the M-score after surgery was markedly correlated with both the preoperative and postoperative INL and CRT thickness. CONCLUSIONS: Both VA and M-score in iERM patients were significantly improved after vitrectomy. Pre- and post-operative CRT was significantly associated with both postoperative BCVA and M-score. Besides, pre- and post-operative INL thickness was correlated to postoperative metamorphopsia, and postoperative BCVA was associated with postoperative ONL+OPL thickness and IS/OS integrity.

Idiopathic Epiretinal Membrane Surgery in Patients Aged Over 80 Years: Efficacy and Safety.

Purpose: To evaluate the efficacy and safety of idiopathic epiretinal membrane (ERM) surgery in patients aged over 80 years. Methods: Consecutive patients who underwent pars plana vitrectomy (PPV) combined with ERM and internal limiting membrane (ILM) peeling with retrobulbar anesthesia were recruited. Based on age, the patients were divided into the elderly group (≥ 80 years of age) and the control group (< 80 years of age). The best-corrected visual acuity (BCVA) and surgical complications were regarded as the main measurement indicators. Results: This study included 43 eyes from 43 patients aged 80 to 91 years and 86 eyes from 86 patients aged 54 to 79 years. Surgical intervention substantially improved BCVA both in the elderly and control groups (p = 0.005 and p < 0.001, respectively). Statistical analyses showed no significant difference in the incidence of surgical complications between the two groups (p = 0.631). The operations in either group were not delayed or canceled for the reason of complications of retrobulbar anesthesia, severe anxiety, or physical discomfort in the perioperative period. Moreover, no patient required a second operation. Also, no stroke, myocardial infarction, or death occurred during the follow-up period. All the surgical complications were treated satisfactorily. Conclusion: Our outcomes indicate that PPV combined with ERM and ILM peeling with retrobulbar anesthesia is effective and safe in elderly patients aged 80 years or older. Based on age alone, we believe that advancing age should not be the risk factor for idiopathic ERM surgery.

Correlation between Severity of Idiopathic Epiretinal Membrane and Irvine-Gass Syndrome.

A higher risk of pseudophakic cystoid macular edema (PCME) has been reported in patients with preoperative idiopathic epiretinal membrane (ERM); however, whether the formation of PCME depends on the grade of ERM has not been well established. We conducted a retrospective case-control study of 87 eyes of 78 patients who were preoperatively diagnosed with idiopathic ERM and had undergone cataract surgery. Patients were divided into two groups: PCME and non-PCME groups. After cataract surgery, the ERM status was graded using the Gass and Govetto classifications. Both the central macular thickness (CMT) and ERM grade increased after surgery, and higher preoperative CMT and ERM grades were found in the PCME group. The association between higher-grade ERM and the development of PCME was significant in the Govetto classification (grade 2, odds ratio (OR): 3.13; grade 3, OR: 3.93; and grade 4, OR: 16.07). The study results indicate that close attention should be given to patients with ERM with the presence of an ectopic inner foveal layer before cataract surgery.

Deep learning-based postoperative visual acuity prediction in idiopathic epiretinal membrane.

BACKGROUND: To develop a deep learning (DL) model based on preoperative optical coherence tomography (OCT) training to automatically predict the 6-month postoperative visual outcomes in patients with idiopathic epiretinal membrane (iERM). METHODS: In this retrospective cohort study, a total of 442 eyes (5304 images in total) were enrolled for the development of the DL and multimodal deep fusion network (MDFN) models. All eyes were randomized into a training dataset with 265 eyes (60.0%), a validation dataset with 89 eyes (20.1%), and an internal testing dataset with the remaining 88 eyes (19.9%). The input variables for prediction consisted of macular OCT images and diverse clinical data. Inception-Resnet-v2 network was utilized to estimate the 6-month postoperative best-corrected visual acuity (BCVA). Concurrently, a regression model was developed using the clinical data and OCT parameters in the training data set for predicting postoperative BCVA. The reliability of the models was subsequently evaluated using the testing dataset. RESULTS: The prediction DL algorithm exhibited a mean absolute error (MAE) of 0.070 logMAR and root mean square error (RMSE) of 0.11 logMAR in the testing dataset. The DL model demonstrated a robust promising performance with R2 = 0.80, notably superior to R2 = 0.49 of the regression model. The percentages of BCVA prediction errors within ± 0.20 logMAR amounted to 94.32% in the testing dataset. CONCLUSIONS: The OCT-based DL model demonstrated sensitivity and accuracy in predicting postoperative BCVA in iERM patients. This innovative DL model exhibits substantial potential for integration into surgical planning protocols.

Comparison of the morphological characteristics of the choroidal sublayer between idiopathic macular holes and epiretinal membranes with automatic analysis.

PURPOSE: To compare the choroidal sublayer morphologic features between idiopathic macular hole (IMH) and idiopathic epiretinal membrane (iERM) on spectral-domain optical coherent tomography (SD-OCT) using an automatic segmentation model. METHODS: Thirty-three patients with idiopathic IMHs and 44 with iERMs who underwent vitrectomies were involved. The enhanced depth imaging mode of SD-OCT was used to obtain the B-scan image after single line scanning of the macular fovea. The choroidal sublayer automatic analysis model divides the choroidal into the choroidal large vessel layer, the middle vessel layer and the small vessel layer (LVCL, MVCL and SVCL, respectively) and calculates the choroidal thickness (overall, LVCL, MVCL and SVCL) and vascular index (overall, LVCL, MVCL and SVCL). The morphological characteristics of the choroidal sublayer in the ERM eyes and the IMH eyes were compared. RESULTS: The mean choroidal thickness in the macular centre of the IMH eyes was significantly thinner than that of the ERM eyes (206.35 ± 81.72 vs. 273.33 ± 82.31 µm; P < 0.001). The analysis of the choroidal sublayer showed that the MVCL and SVCL macular centres and 0.5-1.5 mm of the nasal and temporal macula were significantly thinner in the IMH eyes than in the ERM eyes (P < 0.05), and there was a difference in the macular centre of the LVCL between the two groups (P < 0.05). In contrast, the choroidal vascular index of the macular centre in the IMH eyes was significantly higher than that in iERM eyes (0.2480 ± 0.0536 vs. 0.2120 ± 0.0616; P < 0.05). There was no significant difference in the CVI of other parts of the macula, the LVCL or MVCL between the two groups. CONCLUSION: The choroidal thickness of the IMH eyes was significantly thinner than that of the iERM eyes, which was mainly observed in 3 mm of the macular centre and the MVCL and SVCL layers of the choroid. The choroidal vascular index of the IMH eyes was higher than that of the iERM eyes. These findings suggest that the choroid may be involved in the pathogenesis of IMH and iERM.

Quantitative assessment of retinal microvascular remodeling in eyes that underwent idiopathic epiretinal membrane surgery.

Purpose: To explore the surgical outcomes of the macular microvasculature and visual function in eyes with idiopathic epiretinal membrane (iERM) using spectral-domain optical coherence tomography angiography (SD-OCTA). Methods: This observational, cross-sectional study included 41 participants who underwent iERM surgery with a 3-month (3M) follow-up. Forty-one healthy eyes formed the control group. The assessments included best-corrected visual acuity (BCVA) and mean sensitivity (MS) by microperimetry and SD-OCTA assessment of vessel tortuosity (VT), vessel density (VD), foveal avascular zone, and retinal thickness (RT). Results: The findings showed statistically significant differences in VT, foveal avascular zone parameters, RT, BCVA, and MS between the iERM and control groups (p < 0.05). After iERM surgery, the macular VT, SCP VD, and RT decreased significantly (p < 0.01) while the DCP VD increased (p = 0.029). The BCVA improved significantly (p < 0.001) and was associated with the MS (rs = -0.377, p = 0.015). MS was associated with the SCP VD and RT at 3M (SCP VD rs = 0.511, p = 0.001; RT rs = 0.456, p = 0.003). In the superior quadrant, the MS improved significantly (p < 0.001) and the improvement of MS was associated with the reduction of VT (ß = -0.330, p = 0.034). Conclusion: Microcirculatory remodeling and perfusion recovery were observed within 3 months after iERM surgery. VT was a novel index for evaluating the morphology of the retinal microvasculature in eyes with iERM and was associated with MS in the superior quadrant.

Total and horizontal distances of the foveal stereotaxic displacement can be prognostic indicators for patients with idiopathic epiretinal membrane.

Introduction: This study aimed to examine the foveal stereo deviations in the different ectopic inner foveal layer (EIFL) stages of idiopathic epiretinal membrane (iERM) and assess its predictive utility for the baseline and postoperative best-corrected visual acuity (BCVA). Methods: Based on the calculational combination of foveal displacements in the horizontal and vertical axial optical coherence tomography (OCT) images, the foveal stereotaxic displacement was estimated through the total distance (TD, the distance from the foveal bottom to the inner edge of displaced central foveal) and horizontal distance (HD, projection of the TD in the retinal plane). The preoperative TD, HD, and other OCT- and OCT angiography (OCTA)-related indicators were obtained. The correlations between structural parameters and baseline and postoperative BCVA were evaluated through correlation and multiple linear regression analyses. Results: In patients with advanced EIFL stage, there was a significant increase in the HD, TD, baseline log of the minimum angle of resolution unit for BCVA, central macular thickness (CMT), acircularity index, and incidence of microcystic macular edema (MME; p < 0.05). Further, they showed a decreased foveal avascular zone (FAZ) area and perimeter (p < 0.001). HD, TD, CMT, MME, FAZ area, and FAZ perimeter were significantly correlated with the baseline and postoperative BCVA (p < 0.05). TD had the highest correlation indexic and was an individual predictor of the baseline and postoperative BCVA. Moreover, FD-300 and MME were individual predictors of postoperative BCVA. Discussion: Stereoscopic foveal deviations significantly correlated with the baseline and postoperative visual acuity. TD may be used as an independent prognostic factor for BCVA.

Long-Term Visual Acuity and Optical Coherence Tomography Changes After Vitrectomy for Idiopathic Epiretinal Membranes.

Objective: To evaluate the long-term visual acuity and retinal thickness changes after pars plana vitrectomy (PPV) for idiopathic epiretinal membranes (ERM). Methods: We performed a retrospective analysis of 72 patients who underwent PPV for idiopathic ERM in a tertiary hospital over 5 consecutive years. The main outcome measurement was change in visual acuity and macular thickness as recorded with optical coherence tomography (OCT). Results: Medical records of 239 patients with a diagnosis of ERM who underwent PPV with or without internal limiting membrane (ILM) peeling were reviewed; of these, 72 patients with idiopathic ERM were included in the final analysis. All patients completed at least one year of follow-up, and 23 patients (30%) had 5 or more years of follow-up. The mean preoperative best corrected visual acuity (BCVA) was 20/65, and mean preoperative central macular thickness (CMT) on OCT was 434 microns (µm). Mean postoperative BCVA and CMT at one year were 20/40 and 303 µm, respectively (p<0.0001). A total of 42 patients (58%) improved by 2 or more lines; BCVA and CMT continued to improve postoperatively for up to 5 years of the follow-up period. There was no significant difference in BCVA or CMT between phakic and pseudophakic patients, and ILM peeling was performed in 67% of patients. Improved BCVA at 1 year was associated with younger age (p<0.0001) and ILM peeling (p=0.020). Conclusion: PPV is an effective treatment for idiopathic ERM, and ILM peel may be of benefit. BCVA continues to improve up to 2 years and beyond after surgery regardless of the duration of symptoms.

Effects of disorganization of retinal inner layers for Idiopathic epiretinal membrane surgery: the surgical status and prognosis.

BACKGROUND: To compare the surgical status in idiopathic epiretinal membrane (IERM) patients with or without disorganization of retinal inner layers (DRIL) and to correlate with optical coherence tomography angiography (OCTA) and clinical data. METHODS: In 74 eyes from 74 patients with IERM treated by surgery with 12-month follow-up. According to the superficial hemorrhage, the patients were divided into group A (no macular bleeding), group B (macular parafoveal bleeding) and group C (macular foveal bleeding). Optical coherence tomography (OCT) were evaluated for presence of DRIL,central retina thickness and integrity of the inner/outer segment layer recorded at baseline and at 1, 3, 6, and 12 months postoperatively and best-corrected visual acuity (BCVA) was recorded simultaneously. OCTA was conducted at 12 months postoperatively. Main outcome measures is correlation between DRIL and superficial hemorrhage in membrane peeling,and BCVA and OCTA outcomes postoperatively. RESULTS: The rate of DRIL and BCVA had statistically significant differences between the three groups at the time points(baseline and 1, 3, 6, and 12 months after surgery), respectively (P < 0.001 for all). FD-300 value (P = 0.001)and DCP in all parafoveal regions (superior: P = 0.001; inferior: P = 0.002;Nasal: P = 0.014;Tempo: P = 0.004) in eyes with DRIL were lower than those without DRIL.There was a linear regression relationship between FD-300 and postoperative BCVA (P = 0.011). CONCLUSION: IERM Patients with DRIL have more intraoperative adverse events and limited benefits from surgery which should be considered in the decision whether to perform mebrane peeling.OCT-A provides more detailed vascular information that extends our understanding of persistent DRIL.

Effect of internal limiting membrane peeling for idiopathic epiretinal membrane.

Purpose: To further evaluate the necessity of internal limiting membrane (ILM) peeling for patients with idiopathic epiretinal membrane (iERM). Method: We searched PubMed, Web of Science, Embase, Cochrane Library, and CNKI from their inception up to August 24, 2021. Eligible meta-analyses comparing iERM removal with and without ILM peeling were included. AMSTAR and GRADE classification was used to assess the methodological quality of each study and the quality for each outcome, respectively. The primary outcomes were best-corrected visual acuity (BCVA), central macular thickness (CMT), and recurrence. Results: 10 meta-analyses were included. 75.9% of studies revealed no statistically significant difference in BCVA between the groups, while only 10.3% showed better BCVA favorable to additional ILM peeling. 54.2% reported no significant difference in CMT between the groups, followed by 41.7% showing thicker CMT due to additional ILM peeling. Compared to iERM removal alone, additional ILM peeling provided a lower recurrence rate in 66.7% of studies. Conclusion: ILM peeling could significantly reduce recurrence rate, but not significantly improve the recovery of visual outcome or decrease the thickness of central macula.

Retinal Vascular Tortuosity Index Change after Idiopathic Epiretinal Membrane Surgery: Does Internal Limiting Membrane Peeling Affect Retinal Vascular Tortuosity?

BACKGROUND: Idiopathic epiretinal membrane (iERM) surgery is one of the most commonly performed vitreoretinal surgeries, and the issue of internal limiting membrane (ILM) peeling in ERM surgery is still controversial. The aims of this study are to evaluate the changes in retinal vascular tortuosity index (RVTI) after pars plana vitrectomy for the iERM using optical coherence tomography angiography (OCTA) and to assess whether ILM peeling has an additional effect on RVTI reduction. METHODS: This study included25 eyes of 25 iERM patients who underwent ERM surgery. The ERM was removed without ILM peeling in 10 eyes (40.0%), and the ILM was peeled in addition to the ERM in 15 eyes (60.0%). The existence of the ILM after ERM peeling was checked with second staining in all eyes. Best corrected visual acuity (BCVA) and 6 × 6 mm en-face OCTA images were recorded before surgery and at the first month postoperatively. A skeleton model of the retinal vascular structure was created following Otsu binarization of en-face OCTA images using ImageJ software (1.52U). RVTI was calculated as the ratio of each vessel length to its Euclidean distance on the skeleton model using the Analyze Skeleton plug-in. RESULTS: The mean RVTI declined from 1.220 ± 0.017 to 1.201 ± 0.020 (p = 0.036) in eyes with ILM peeling and from 1.230 ± 0.038 to 1.195 ± 0.024 in eyes without ILM peeling (p = 0.037). There was no difference between the groups in terms of postoperative RVTI (p = 0.494). A statistically significant correlation was found between postoperative RVTI and postoperative BCVA (rho = 0.408, p = 0.043). CONCLUSIONS: The RVTI is an indirect indicator of the traction created by the iERM on retinal microvascular structures, and it was effectively reduced after iERM surgery. The postoperative RVTIs were similar in cases who underwent iERM surgery with or without ILM peeling. Therefore, ILM peeling may not have an additive effect on the loosening of microvascular traction and thus may be reserved for recurrent ERM surgeries.

Short-term postoperative changes in the choroidal vascularity index in patients with a unilateral epiretinal membrane.

BACKGROUND: To investigate short-term choroidal structural and vascular changes after epiretinal membrane (ERM) surgery. METHODS: In this retrospective study, 65 patients with unilateral ERM underwent pars plana vitrectomy combined with cataract surgery and were examined one day before surgery and one week, one month, and three months after surgery. Choroidal thickness (CT) and choroidal vascular index (CVI) were evaluated using horizontal enhanced depth imaging optical coherence tomography (EDI-OCT) scans and were further calculated using semi-automatic algorithms using MATLAB R2017a. RESULTS: Preoperatively, CVI was higher in eyes with ERM (61.70 ± 5.17%) than in fellow eyes (59.99 ± 5.26%). CVI increased significantly at one week after surgery (62.14 ± 5.02%) and decreased at 1 and 3 months after surgery (60.76 ± 4.97% and 60.4 ± 4.83%, respectively). The change was pronounced in the nasal region (p < 0.001) and central region (p < 0.05). CT in the temporal macula increased at 1 week (239.65 ± 72.98 µm) after surgery and decreased at 1 and 3 months after surgery (222.15 ± 71.91 µm and 222.33 ± 65.72 µm, respectively; p < 0.01). CONCLUSIONS: Short-term postoperative variations in the choroid have been demonstrated in eyes with ERM. This may be related to the release of macular traction. CVI assessment using EDI-OCT may be a useful tool for investigating choroidal structural changes accompanying ERM and postoperative period.

Evaluation of the optical coherence tomography findings of patients with idiopathic epiretinal membrane.

BACKGROUND: This study aimed to determine the relationship between basal visual acuity (VA) and basal optical coherence tomography (OCT) parameters of patients with idiopathic epiretinal membrane (iERM). METHODS: The study included 200 eyes of 200 patients with iERM. In the evaluation of basal VAs, logMAR 0.3 (0.5 on Snellen chart) was accepted as the limit, and the patients were divided into two groups as Group 1 with VA values below logMAR 0.3 and Group 2 with those above logMAR 0.3. Using OCT, the ellipsoid zone (EZ), interdigitation zone (IZ), external limiting membrane (ELM) integrity, peaked appearance of EZ in the fovea, disorganization of the inner retinal layers (DRIL), central foveal thickness (CFT), maximum retinal thickness (MRT), total photoreceptor length (TPL), photoreceptor outer segment length (PROSL), photoreceptor deformity index (PDI), and inner retinal layer irregularity index (IRLII) were evaluated and compared between the groups. RESULTS: There were an equal number of patients in Group 1 and Group 2. The preservation of ELM, EZ, and IZ integrity and the peaked appearance of EZ in the fovea were observed at higher rates in Group 1, whereas the rate of DRIL was higher in Group 2 (p < 0.05 for all). In the multiple regression analysis performed to evaluate categorical OCT parameters, only the presence of DRIL was found to be significantly associated with VA (p < 0.003). CFT*, MRT*, and IRLII** were significantly lower in Group 1 (*p < 0.001, **p = 0.001). TPU, PROSL, and FDI were similar between the two groups (p > 0.05 for all). CONCLUSION: According to the multiple regression analysis, only the presence of DRIL was correlated with lower VA values. Among the OCT parameters, an increase in CFT and MRT, as well as the IRLII value moving away from 1 were related to lower VA values.

Screening of idiopathic epiretinal membrane using fundus images combined with blood oxygen saturation and vascular morphological features.

PURPOSE: To achieve an accurate diagnosis of idiopathic epiretinal membrane (iERM) through analyzing retinal blood vessel oxygen saturation (SO2) and vascular morphological features in fundus images. METHODS: Dual-modal fundus camera was used to obtain color fundus image, 570-nm, and 610-nm images. As iERM affects the macular area, a macular-centered semicircle area as region of interest (MROI) was selected and analyzed SO2 and vascular morphologies in it. Eventually, random forest (RF) and support vector machine (SVM) were as classifiers to diagnose iERM patients. RESULTS: The arterial and venous SO2 levels of the iERM group were significantly higher than that of the control group. There were significant differences in the vessel density and fractal dimension on the artery for vascular morphology, while the tortuosity had a significant difference in the vein. By feeding the SO2 and the vascular morphological features into classifiers, an accuracy of over 82% was obtained, which is significantly better than the two separate inputs for classification. CONCLUSION: Significant differences in SO2 and vascular morphologies between control and iERM groups confirmed that the occurrence of iERM may affect blood supply and vascular structures. Benefiting from the dual-modal fundus camera and machine learning models, accurate judgments can be made on fundus images. Extensive experiments proved the importance of blood vessel SO2 and vascular morphologies for diagnosis, which is of great significance for clinical screening.