Idiopathic Epiretinal Membrane: Microvasculature Analysis with Optical Coherence Tomography and Optical Coherence Tomography Angiography

Background: The present study examined the relationships among macular microvasculature, retinal structure, and epiretinal membrane (ERM) and explored the utility of optical coherence tomography (OCT) angiography (OCTA) in idiopathic ERM assessment. Methods: The study sample comprised 276 eyes of 276 patients. A total of 154 eyes with ERM and 122 normal (control) eyes were analyzed. Only one eye of each participant was randomly selected for posterior segment imaging. Each patient underwent OCT and OCTA. Images were analyzed with AngioTool 0.6. Results: Foveal avascular zone was significantly smaller in the ERM group (p = 0.044). Average retinal thickness and foveal thickness were significantly higher in the ERM group (both p = 0.001). Moreover, 64 (41.5%) patients exhibited no metamorphopsia, while 46 (29.8%) and 44 (28.7%) patients exhibited moderate and extensive metamorphopsias, respectively. Meanwhile, FAZ was negatively correlated with central retinal thickness in the ERM group. The vessel area (p = 0.0017) and vessel percentage area (p = 0.044) were significantly greater in the ERM group. Conclusions: Changes observed in the superficial plexus in OCTA are related to the severity of metamorphopsia and can be further evaluated to support decision making regarding the surgical management of idiopathic ERM.

Efficacy and safety of primary posterior capsulotomy during phaco-vitrectomy for epiretinal membrane

Purpose To evaluate the necessity and safety of primary posterior capsulotomy during phaco-vitrectomy for idiopathic epiretinal membrane (ERM). Setting Seoul National University Bundang Hospital, Seongnam, Korea. Design Retrospective consecutive cohort analysis. Methods This study enrolled 219 patients (228 eyes) who underwent combined 25-gauge phaco-vitrectomy for idiopathic ERM and cataract, divided into capsulotomy (−) group (152 eyes, 144 patients) and capsulotomy (+) group (76 eyes, 75 patients). The main outcomes were rate of posterior capsular opacity (PCO) occurrence and postoperative complications. Ophthalmic examinations were performed at baseline, 1, 3, 6, and 12 months postoperatively. Results PCO only occurred in capsulotomy (−) group (20 eyes, 13.2%), with mean onset of 10.59 months. Visually-significant PCO that needed Nd:YAG posterior capsulotomy was present in 9 eyes (45.0% of PCO eyes). The rate of cystoid macular edema (CME) was higher in capsulotomy (+) group (6.6% vs. 15.8%, p = 0.026) with longer duration (1.50 vs. 3.36 months, p = 0.019). Female sex and posterior capsulotomy were significant risk factors for CME occurrence (p < 0.05). Conclusion Primary posterior capsulotomy during phaco-vitrectomy for idiopathic ERM obviated the need for Nd:YAG posterior capsulotomy, but visually-significant PCO that needed Nd:YAG laser was not common. Considering the low rate of visually-significant PCO and high rate of postoperative CME, routine posterior capsulotomy during phaco-vitrectomy may not be necessary for preventing PCO in ERM.

Two-year Changes in Postoperative Central Macular Thickness and Subfoveal Choroidal Thickness in Epiretinal Membrane Patients

Purpose: To evaluate changes in central macular thickness (CMT) and subfoveal choroidal thickness (SFCT) after phacovitrectomy over a 2-year period in idiopathic epiretinal membrane (ERM) patients.Methods: The records of 52 idiopathic ERM patients (52 eyes) who underwent phacovitrectomy, without recurrence of the condition over a 2-year follow-up period, were reviewed retrospectively. Changes in CMT and SFCT, as measured by optical coherence tomography, were analyzed and compared with those of a normal control group over a 2-year period.Results: The mean preoperative CMT and SFCT were 425.67 ± 84.67 and 257.56 ± 90.13 μm, respectively. Postoperative CMT was reduced significantly to 372.17 ± 45.26 μm at 1 year and 363.15 ± 47.35 μm at 2 years (p < 0.001). SFCT at 1 and 2 years postoperatively was significantly reduced to 238.85 ± 84.85 and 230.31 ± 87.95 μm, respectively (p < 0.001). In the control group, there was no significant change in CMT; however, the SFCT decreased by 11.09 ± 22.36 μm during the 2-year follow-up (p = 0.007). In contrast, in the patient group, CMT and SFCT decreased by 62.52 ± 71.45 and 27.25 ± 41.97 μm, respectively, showing a significant difference from the control group (p < 0.001 and p = 0.043, respectively). Both before surgery and at 1 year postoperatively, the thinner the CMT, the better the best-corrected visual acuity (BCVA) (p = 0.010 and p = 0.018, respectively). A better postoperative BCVA at 2 years was associated with a thinner CMT and better BCVA before surgery (p < 0.001 and p < 0.001, respectively).Conclusions: Following a phacovitrectomy procedure, ERM patients showed significant reductions in both the CMT and SFCT at the 2-year follow-up.