Functional and Morphological Results of Epiretinal Membrane Surgery in Idiopathic versus Diabetic Epiretinal Membranes

Comparison of postoperative morphological changes and retinal displacement in diabetic and idiopathic epiretinal membranes

PURPOSE

To compare the postoperative retinal displacement by optical coherence tomography (OCT) in idiopathic epiretinal membranes (iERM) and diabetic epiretinal membranes (dERM).

METHODS

This retrospective study included 36 iERM and 22 dERM cases. In cross-sectional OCT images (B-scan) the presence of foveal pit, subfoveal fluid, cotton ball sign (CBS), intraretinal cystic changes (ICC), disorganization of retinal inner layers (DRILs) and ectopic inner foveal layer (EIFL) were recorded. Central macular thickness (CMT) and EIFL thicknesses were calculated. Retinal displacement was quantified using infrared image of OCT approach consisting of the fovea to disc margin, interarcade distance and perimacular distances.

RESULTS

The presence of subfoveal fluid (p = 0.014) and DRIL (p = 0.02) was significantly higher in the dERM group. CMT decreased significantly in both groups (p˂0.001). The EIFL was significantly thicker in the iERM group compared to the dERM group (p = 0.049), and it decreased significantly in the iERM group postoperatively. In the iERM group, while the fovea-disc margin distance decreased, the interarcade and perimacular distance increased significantly (p˂0.001). In the dERM group, the disc-fovea distance change was not significant (p = 0.082). Significant visual improvement was achieved with vitrectomy in both groups (p˂0.001). In the dERM group, the presence of DRIL was associated with lower pre and post-op visual acuity (VA) (r = 0.596 and p = 0.004 for pre-operative and r = 0.567 and p = 0.007 for post-operative).

CONCLUSION

Significant retinal displacement occurs after vitrectomy in both iERM and dERM. The low VA in the dERM group may be related to the presence of DRILs.

Choroidal Vascularity Index Fluctuations in Epiretinal Membranes in Vitreoretinal Surgery: Comparison Between Idiopathic and Diabetic Ones

Purpose

The aim of the study was to analyze choroidal vascularity index (CVI) fluctuations in patients with epiretinal membrane after vitreoretinal surgery, comparing idiopathic and secondary diabetic ones.

Methods

Thirty eyes suffering from idiopathic ERMs (I-ERMS; n = 15) and diabetic ERMs (D-ERMS; n = 15) were analyzed in this observational prospective study. Anatomical (central macular thickness) and functional (best-corrected visual acuity) parameters were analyzed preoperatively and at 1 and 3 months after vitrectomy. Perfusion findings regarding CVI and luminal area were also calculated.

Results

At 1 month after surgery, the luminal area and CVI significantly decreased in the I-ERMS group, whereas they were increased in the D-ERMS group. At the 3-month follow-up, the CVI tended to return to baseline values in I-ERMS and to reduce in D-ERMS, but without any statistical differences.

Conclusions

The significant change in the CVI after surgery seems to imply that the choroidal layer is affected by vitreomacular disease and can become a novel potential biomarker of predictiveness in vitreoretinal surgery.

Translational Relevance

The aim of the study was to focus on the early choroidal changes to better understand initial predictive elements of long-term functional postoperative outcomes.

Effect of Internal Limiting Membrane Peeling or Not on Blood Flow Signal in Macular Area of Diabetic Patients with Preretinal Membrane

PURPOSE

To study the effect of intraoperative internal limiting membrane (ILM) peeling on the macular vascular structure in patients with diabetic epiretinal membrane (ERM).

METHODS

Patients with diabetic ERM were divided into an ERM + ILM peeling group (18 eyes) and an ERM peeling group (19 eyes), all of whom underwent standard vitrectomy and were followed up until 6 months postoperatively. Best-corrected visual acuity (BCVA), Central macular thickness (CMT), Vessel density (VD) and vessel length density (VLD) of the superficial as well as deep retinal capillary plexus were compared between the two groups.

RESULTS

There was no significant difference in BCVA (p = .188, .410, .901, .916) and CMT (p = .164, .128, .110, .105) between the two groups at the week 1, month 1, month 3 and month 6 after operation. In the superficial capillary plexus (SCP), the change in VD (p = .106) and VLD (p = .438) was not affected by ILM peeling, and there was no significant difference in VD (p = .154, .063, .100, .162) and VLD (p = .386, .263, .431, .391) between the two groups during the four follow-up after operation. For the deep capillary plexus (DCP), there was an effect of ILM peeling on the changes in VD (p = .024) and VLD (p = .012), ILM peeling delayed the recovery time of the VD and VLD; The VD (p = .026, .000, .003) and VLD (p = .005, .000, .000) of ERM + ILM peeling group were lower than those of ERM peeling group from the month 1 to the month 6 after operation.

CONCLUSION

Intraoperative peeling of the ILM in patients with diabetic ERM delayed the improvement of blood flow signal in the DCP but did not affect the recovery of postoperative BCVA and CMT.