Effects of Internal Limiting Membrane Peel for Idiopathic Epiretinal Membrane Surgery: A Systematic Review of Randomized Controlled Trials

PURPOSE

The purpose of this study was to compare functional and anatomical outcomes after epiretinal membrane (ERM) peeling with internal limiting membrane (ERM/ILM) peeling and without for the treatment of idiopathic ERM.

DESIGN

Systematic review and meta-analysis.

METHODS

A comprehensive search of Cochrane CENTRAL, MEDLINE Ovid, and Embase Ovid for randomized controlled trials comparing ERM/ILM with ERM was performed. Two independent reviewers selected papers and extracted data. Methodological quality was assessed using the Cochrane Risk of Bias (RobVis) tool. Data was analyzed using RevMan 5.3. Quality of body of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

Seven studies reporting 387 eyes overall were included. A total of 207 eyes (53%) received ERM/ILM. A total of 180 (47%) received ERM. Post-operative visual acuities (logMAR) were not significantly different between ERM/ILM and ERM, with a mean difference (MD) of 0.02 (95% confidence interval [CI]: -0.04 to 0.09; P = .45; I²= 42%; n = 101) at 1 month; 0.03 (95% CI: -0.01 to 0.06; P = .11, I² = 15%; n = 299; High Certainty of Evidence) at 3 months; 0.01 (95% CI: -0.03 to 0.04; P = .72; I² = 21%; n = 317; High Certainty of Evidence) at 6 months; and 0.01 (95% CI: -0.02 to 0.04; P = .49; I² = 39%; n = 234) at 12 months post-operatively. ERM/ILM was significantly associated with lower ERM recurrence at 6-12 months with a relative risk of 0.16 (95% CI: 0.04-0.64; P = .01; I² = 0%; n = 155; Moderate certainty of evidence) and an increased central macular thickness (micrometers) at 12 months with an MD of 20.53 (95% CI: 4.96-36.09; P = .01; I² = 12%; n = 234).

CONCLUSIONS

ERM/ILM and ERM result in similar visual acuity despite subtle differences in anatomical outcomes (central macular thickness). ERM/ILM is associated with a significantly lower rate of ERM recurrence at 6-12 months post-operatively and should be considered where recurrence prevention is the treatment priority.

Pathophysiological correlations between fundus fluorescein angiography and optical coherence tomography results in patients with idiopathic epiretinal membranes

The aim of the current study was to determine the association between fundus fluorescein angiography (FFA) image results, optical coherence tomography (OCT) imaging results and visual functions in patients with idiopathic epiretinal membranes (ERMs). A total of 80 eyes from 40 patients diagnosed with ERM were analyzed. Best-corrected visual acuity (BCVA) and metamorphopsia were measured using the Early Treatment Diabetic Retinopathy Study eye chart and M-charts, respectively. Macular thickness and volume were determined using OCT. Macular vascular leakage and distortion, and foveal avascular zone (FAZ) diameters were assessed using FFA. BCVA and M-chart results confirmed macular degeneration in the affected eyes. The area of macular vascular leakage was positively correlated with macular volume (r=0.50; P=0.001). The ratio of FAZ diameters was negatively correlated with central macular thickness (r=-0.41; P=0.008). The grade of macular vascular distortion was positively correlated with macular thickness (all r≥0.47; P<0.01) and volume (r=0.53; P<0.001). The results of the current study demonstrated that FFA may effectively identify the degree of changes in retinal macular vasculature. Vascular distortion, measured by FFA, may reflect changes in macular structure and visual functions. These results suggest a potential application of FFA in the pre- and post-surgical evaluation of patients with ERMs.

Comparison of Macular Findings due to Vitreomacular Traction Alone or in Association with Epiretinal Membrane

Purpose

To evaluate the anatomical and functional findings in patients with vitreomacular traction (VMT) alone or in combination with epiretinal membrane (ERM).

Methods

In this retrospective, cross-sectional study, we studied 102 patients with VMT, either alone (n = 37) or combined with ERM (n = 65). All patients were examined with spectral-domain optical coherence tomography (SD-OCT). We recorded the vitreofoveal angle of VMT nasally and temporally, the horizontal diameter of VMT, macular thickness, the presence, type, and location of macular edema, the ellipsoid zone (ΕΖ)/external limiting membrane (ELM) status, and the visual acuity.

Results

Patients with VMT combined with ERM presented smaller vitreofoveal angle nasally and temporally, broader adhesion diameter, and a greater extent of EZ defect compared to patients with VMT alone, although there was no statistically significant difference in EZ and ELM condition regarding the number of affected cases. There is also no statistically significant difference between the 2 groups concerning the visual acuity. In the majority of patients with VMT alone, cystoid macular edema was present mainly at the foveal area. In cases where VMT coexisted with ERM, macular edema was mostly found to be diffuse, while cystoid or mixed type, extending to the whole macular area, was also present.

Conclusions

Patients with VMT in association with ERM have different characteristics in SD-OCT compared to those with VMT alone regarding the type and location of macular edema, the extent of EZ defect, as well as the vitreofoveal angle and the VMT diameter. Moreover, they presented worse visual acuity compared to those with VMT alone, although the difference did not reach statistical significance.

Long-Term Anatomical and Functional Results in Patients Undergoing Observation for Idiopathic Nontractional Epiretinal Membrane

Purpose

To evaluate the anatomical and functional course without surgical intervention in patients with nontractional epiretinal membrane (ERM) using spectral-domain optical coherence tomography (SD-OCT) in a long-term follow-up of 38.2 ± 30.6 months.

Methods

Participants were 58 patients with nontractional ERM, which was defined as a tear or rip of the ERM in at least one line of OCT scan. All patients were observed without any surgical intervention. All patients underwent ophthalmologic examination, including best-corrected visual acuity (BCVA) measurement, funduscopy, and SD-OCT. Routine follow-up visits were performed every 6 months or earlier at the discretion of the investigator.

Results

There was no statistically significant difference in BCVA or central foveal thickness (CFT) at all time points of the follow-up. About 84.4% of patients presented improvement or stabilization in BCVA at the end of the follow-up, while 53.4% of patients had a decrease in CFT. All patients had intact ellipsoid zone and none of them needed surgical intervention at the end of the follow-up of 38.2 ± 30.6 months.

Conclusions

In patients with nontractional ERM, BCVA and CFT may remain stable in a long-term follow-up. Therefore, if ellipsoid zone is intact and there is a tear or rip of ERM in at least one OCT scan, patients can be monitored and surgery may be deferred because of high percentage of structural and functional stability.

Hyperreflective foveal lesion observed with optical coherence tomography in cases of epiretinal membranes with a firm foveal attachment

PURPOSE

To report the optical coherence tomography (OCT) findings of the firmly attached foveal area and to investigate the functional results and predictive values in correlation to the degree of firmness of the foveal adherence of the epiretinal membrane (ERM).

METHODS

We retrospectively reviewed the medical records regarding 167 eyes of 166 patients who underwent vitrectomy for the removal of the ERM between January 2009 and December 2012. We evaluated the degree of foveal attachment in all the patients based on the surgical video and reviewed the OCT images. The main and secondary outcome measures were OCT findings including the presence and the size of a highly reflective lesion, visual acuity, and the mean duration of the ERM before surgery.

RESULTS

An abnormal highly reflective lesion was observed beneath the ERM in the foveal area. We termed this type of finding a "hyperreflective foveal lesion" (HFL). This HFL was present in 22 of 23 eyes (95.7%) with a firm foveal attachment (FFA) and in 2 of 144 eyes (1.4%) without an FFA (P < 0.001). The HFL showed a sensitivity of 96%, specificity of 99%, positive predictive value of 92%, and negative predictive value of 99%, as a predictor of FFA. The mean duration of the ERM before surgery was significantly longer in the group with an FFA than in the group without an FFA (P = 0.029). Regarding the degree of firmness of the adherence in the eyes with an FFA, the group with a greater degree of firmness had a larger HFL as observed with OCT before surgery (P < 0.05). The visual acuity in patients with an FFA was significantly lower than that in patients without an FFA after surgery (P = 0.031).

CONCLUSION

Visual acuity after surgery was significantly lower in patients with an FFA. The presence of an HFL in the OCT demonstrated a high predictive value for firmness of the foveal attachment. The size of an HFL in the OCT was associated with the degree of firmness and allowed us to predict inner and outer retinal damages after surgery.

The photoreceptor layer as a prognostic factor for visual acuity in the secondary epiretinal membrane after retinal detachment surgery: imaging analysis by spectral-domain optical coherence tomography

PURPOSE

To study the prognostic factors that influence best-corrected visual acuity (BCVA) outcome in patients with secondary epiretinal membrane (ERM) after retinal detachment surgery.

DESIGN

Retrospective case series.

METHODS

Forty-two patients with ERM were divided into macula-on and macula-off groups based on the macular status before retinal detachment surgery and were studied using the same spectral-domain optical coherence tomography device. Several variables, including the integrity of the external limiting membrane (ELM), the status of the photoreceptor inner segment/outer segment (IS/OS) junction line, and central foveal thickness were evaluated in 17 treated and 25 untreated patients. Linear regression analysis was used to determine the best combination of all variables affecting BCVA.

RESULTS

Final BCVA was significantly better in macula-on and macula-off eyes with intact ELMs and IS/OS junction lines (0.35 ± 0.18 logarithm of the minimal angle of resolution [logMAR] and 0.51 ± 0.17 logMAR, respectively) than in macula-off eyes with disrupted or absent ELMs and IS/OS junction lines (0.83 ± 0.17 logMAR and 1.04 ± 0.05 logMAR, respectively; P < .001, analysis of variance). Final BCVA also was better in the treated group than in the controls (0.55 ± 0.31 logMAR and 0.73 ± 0.26 logMAR, respectively; P = .05, t test). ELM and IS/OS junction line integrity were the main variables significantly affecting the final BCVA outcome (β = 0.42; P = .006, linear regression analysis). Disruption of the ELM and IS/OS junction line was observed in 21 of the 42 cases studied.

CONCLUSIONS

ERM secondary to retinal detachment surgery is accompanied by a high incidence (50%) of IS/OS junction line and ELM disruption. Among the variables studied, the condition of the IS/OS junction layer and the ELM are the main factors that predict final BCVA after ERM peeling.