CHARACTERISTICS OF EPIRETINAL MEMBRANE REMNANT EDGE BY OPTICAL COHERENCE TOMOGRAPHY AFTER PARS PLANA VITRECTOMY

Persistence and recurrence after removal of idiopathic epiretinal membrane

OBJECTIVES

To analyse the incidence of persistence and recurrence after the peeling of idiopathic epiretinal membrane (ERM) and to describe its clinical features.

METHODS

This retrospective study included 666 eyes (645 patients) that underwent macular surgery for ERM removal. Optical coherence tomographic (OCT) images taken within three months after surgery and at the following visits, clinical parameters and surgery related factors were analysed to investigate the incidence and associated factors of ERM persistence and recurrence. Postoperative ERM types were categorised depending on the size ( < 100 µm, ≥100 µm) and the location (foveal, parafoveal, outside the parafovea) RESULTS: The mean follow-up time was 29.4 months. ERM persistence (examination within 3 months) was found in 29.6% of all eyes. Only 1.9% of the eyes presented foveal ERM persistence. Foveal recurrence, defined as reappearance or growth of persistent ERM covering the fovea, was found in 8.2%. In 84.4% of eyes with foveal ERM recurrence, postoperative persistence of ERM of varying severity were identified. None of the pre-operative or surgery related factors were found significantly associated with ERM recurrence. Persistent ERM within the parafovea was the most significant risk factor for foveal ERM recurrence.

CONCLUSION

Recurrence of ERM is generally preceded by the persistence of ERM fragments found in the early postoperative period. Growth of ERM persistence from the parafoveal region was often the origin of foveal ERM recurrence. Insufficient peeling seems to be the most significant predisposing factor for foveal ERM recurrence.

Long-term Follow-up Results of Idiopathic Epiretinal Membrane Removal in the Eyes with Ectopic Inner Foveal Retinal Layers

PURPOSE

The purpose of this study was to evaluate pre- and perioperative factors related to time for the evolution of ectopic inner foveal layers (EIFL) following pars plana vitrectomy (PPV) for epiretinal membrane (ERM) peeling.

METHODS

This retrospective study included 81 consecutive eyes with idiopathic ERM that underwent vitrectomy surgery. Standard PPV + internal limiting membrane peeling was performed in all cases. A comprehensive ophthalmic examination was performed for all patients before and 1, 3, 6, and 12 months, and the last follow-up after surgery. We observed the postoperative improvement in EIFL severity in the short-term and longest follow-up and evaluated anatomical and functional improvement. Several parameters were assessed using the multivariate COX proportional hazard analysis.

RESULTS

Eighty patients (81 eyes) with a mean age of 70.33 ± 7.75 years were followed for a mean of 34.37 ± 23.61 months, and 55.5% of eyes (45 eyes) with EIFL ERM showed improvement of foveal contour to a better stage at the last follow-up. The median estimated time for evolving to a better stage was 29.73 months for stage 2, 49.68 months for stage 3, and 38.67 months for stage 4 (P = 0.001, log-rank test). The severity of EIFL was the only significant factor for time to evolution of EIFL ERM to a better stage, where the eyes with stage 4 EIFL ERM showed faster foveal contour improvement compared to those with stage 3 EIFL ERM (hazard ratio: 0.317, 95% confidence interval = 0.164-0.615, P = 0.001).

CONCLUSION

On assessing preoperative factors, the preoperative EIFL stage emerged as the sole significant factor for EIFL ERM improvement to a better disease stage. This study reports some of the longest follow-up durations for patients undergoing PPV for EIFL ERM, and both functional and anatomical improvements were observed across all stages of EIFL, including in the advanced stage 4 EIFL ERM.

Comparison of Idiopathic Macular Hole Interventions Using Frequency Domain Optical Coherence Tomography and Optical Coherence Tomography Angiography

Objective

We aimed to determine the efficacy of different idiopathic macular hole treatment methods to improve recovery time and patient outcomes using Frequency Domain Optical Coherence Tomography (SD-OCT) and Optical Coherence Tomography Angiography (OCTA).

Methods

This retrospective study included patients with idiopathic macular hole who were admitted to our hospital between 1st January 2019 and 31st October 2021. The control group was treated with internal limiting membrane tamponade, and the study group was treated with clamshell therapy. Treatment conditions (internal limiting membrane treatment duration and hole closure rate), best corrected visual acuity (BCVA) before and after surgery, OCTA measurements, and SD-OCT were assessed. The retinal nerve fiber layer (RNFL), retinal ganglion cell layer (GCL), and retinal pigment epithelium (RPE) thicknesses were also analyzed.

Results

The treatment time and hole closure rate of the internal limiting membrane in the study group were higher than those in the control group. The curative effect of the study group was better than that of the control group. The postoperative DCP blood vessel density in both groups was higher than that before operation, and the study group was higher than the control group. The FAZ area and circumference were lower than those before surgery, and the study group was lower than the control group. At 3 months after operation, the thickness of DIOA, nasal temporal RNFL, and GCL were decreased in both groups, and the observed values in the study group were lower than those in the control group. At 3-month follow-up, there was no significant difference in RPE thickness between the two groups.

Conclusion

Flip and cover therapy is the most effective treatment. SD-OCT and OCTA provide an objective basis for clinical intervention by comparing the effects of different procedures on the retinal condition of patients.

RECURRENCE OF IDIOPATHIC EPIRETINAL MEMBRANE AND ITS PREDISPOSING FACTORS: An Optical Coherence Tomography Study

PURPOSE

To evaluate the incidence and clinical course of recurrent epiretinal membrane (ERM) after ERM surgery and to identify predisposing optical coherence tomography (OCT) findings for the recurrence.

METHODS

Postoperative ERM recurrence, defined as reappearance of the membrane after its removal or regrowth of the remnant membrane, was investigated in 301 eyes with idiopathic ERM followed up for more than 6 months after macular surgery by fundus photographs and spectral-domain OCT. The incidences of recurrent ERM and its associated clinical characteristics were assessed. Preceding OCT findings in the area subsequently showing recurrent ERM were evaluated at early postoperative periods.

RESULTS

Among the 301 eyes that underwent ERM peeling, 119 (39.5%) and 86 (28.6%) showed ERM recurrence on OCT images and biomicroscopic examination/fundus photographs, respectively, during the follow-up period (average: 18.1 months). Neighboring remnant membrane and hyperreflective dots on the retinal surface at 1 week after the surgery and postoperative inner retinal wrinkling persisting for ≥1 month were predisposing OCT findings for ERM recurrence, with an odds ratio of 6.48 (95% confidence interval, 3.51-12.0), 3.48 (95% confidence interval, 1.81-6.70), and 6.11 (95% confidence interval, 3.30-11.3), respectively (all P < 0.001).

CONCLUSION

Incidence of ERM recurrence varies depending on the definition used for the recurrence. Optical coherence tomography examination may be useful for the prediction and sensitive detection of recurrent ERM.

En Face Image-Based Analysis of Epiretinal Membrane Formation after Surgery for Idiopathic Epiretinal Membrane

PURPOSE

To analyze en face epiretinal membrane (ERM) images constructed using swept-source (SS) OCT and to determine the incidence of ERM formation after ERM surgery and its effects on visual function.

DESIGN

Retrospective, consecutive observational study.

PARTICIPANTS

Consecutive series of 73 eyes (71 patients) with idiopathic ERM that underwent vitrectomy with both ERM and internal limiting membrane (ILM) peeling.

METHODS

We retrospectively reviewed the data of the 73 eyes included in the study. During surgery, the ERM was removed as extensively as possible, and the ILM was removed such that the area of ILM peeling was at least larger than the parafoveal area. All patients underwent comprehensive ophthalmologic examinations, including assessments of best-corrected visual acuity and metamorphopsia, before and at 2 weeks and 6 months after the surgery. En face images constructed using SS OCT were used to investigate ERM formation.

MAIN OUTCOME MEASURES

The incidence of ERM formation at 6 months after the surgery, effects of ERM formation on visual function, and the relationship between ERM formation and the extent of ERM and ILM peeling.

RESULTS

At 6 months after ERM and ILM peeling, 8 eyes (11.0%) showed ERM formation (formation group). Twenty eyes (27.4%) exhibited remnant ERM without ERM formation (remnant group), whereas 45 eyes (61.6%) showed no ERM (no ERM group). In both the remnant and no ERM groups, best-corrected visual acuity and metamorphopsia showed significant improvements after ERM surgery (both P < 0.01); these improvements were not seen in the formation group (P = 0.067 and P = 0.053, respectively). However, no significant differences were found in preoperative and postoperative best-corrected visual acuities and metamorphopsia among the 3 groups. In the formation group, ERM formation occurred only in the area with residual ILM. Most patients who underwent ILM peeling in which the area of the peeling covered the ERM belonged to the no ERM group (97.7%; P < 0.01).

CONCLUSIONS

Epiretinal membrane formation does not affect visual function significantly when the area of ILM peeling is larger than the parafoveal area. When the ILM peeling area covers the ERM area, postoperative ERM formation can be prevented.

Long-term evaluation of spontaneous release of epiretinal membrane and its possible pathogenesis

PURPOSE

To investigate the characteristics in spontaneous release of epiretinal membrane (ERM) during watchful waiting and to introduce a possible mechanism of pathogenesis as a photo essay.

METHODS

Records from all patients with ERM were obtained from Osaka Medical College Hospital from January 2001 to October 2012. Visual acuity (VA), fundus photo, and optical coherence tomography (OCT) were reviewed using the medical records. For statistical analysis, VA measured with a Landolt chart was converted to the logarithm of the minimum angle of resolution (logMAR). To investigate the pathogenesis of ERM, tryptase activity in vitreous, which plays a role in tissue fibrosis and remodeling, was measured in patients that underwent a vitrectomy for ERM, macular hole, and proliferative diabetic retinopathy (PDR).

RESULTS

ERM was observed in 604 patients and spontaneous release of the ERM was observed in 13 patients with 14 eyes (four males and nine females, aged 33-78 years). Among the 14 eyes, mean VA did not change significantly through the release of the ERMs (0.17±0.18 before and 0.24±0.40 after release, P=0.544). Nine eyes showed posterior vitreous detachment or vitreomacular traction on OCT images and five eyes did not. ERM was released in five eyes with no accompanying vitreous traction by OCT during watchful waiting and seems to have peeled off by itself by contracting and rolling from the inferior side. Three eyes with deteriorated VA underwent vitrectomy due to macular hole or pseudomacular hole. Vitreal tryptase activity was significantly higher in patients with ERM compared to those with PDR (P<0.05).

CONCLUSION

Fundus photos of ERM auto-peeling were taken during long-term follow-up. Spontaneous release of ERM is possibly involved in vitreous traction or membrane contraction. In addition, tryptase may be involved in the development and contraction of ERM.