RESUMO
Purpose. To assess functional and morphological alterations following video-documented surgery for epiretinal membranes. Methods. Forty-two patients underwent video-documented 23-gauge vitrectomy with peeling of epiretinal (ERM) and inner limiting membrane (ILM). Patient assessment was performed before and 3 and 6 months including best corrected visual acuity (BCVA), slit lamp biomicroscopy, SD-OCT, and central 2° and 18° microperimetry. In addition, all video-documented areas of peeling on the retinal surface were evaluated postoperatively using an additional focal 2° microperimetry. Retinal sensitivity and BCVA were correlated with morphological changes (EZ and ELM) in the foveal region and in regions of membrane peeling. Results. Overall, BCVA increased from 0.6 (±0.2) to 0.2 (±0.2) logMAR after 6 months with an increase in retinal sensitivity (17.9 ± 2.7 dB to 26.8 ± 3.1 dB, p < 0.01). We observed a significant correlation between the integrity of the EZ but not of the ELM and the retinal sensitivity, overall and in peeling areas (p < 0.05). However, no significant correlation between alterations in the area of peeling and overall retinal sensitivity regarding visual acuity gain could be observed after 6 months (p > 0.05). In contrast, overall postoperative retinal sensitivity was significantly decreased in patients with a visual acuity gain lower than 2 lines (p < 0.05) correlating with EZ defects seen in OCT. Conclusions. Mechanical trauma of epiretinal membrane and ILM peeling due to the use of intraocular forceps may affect the outer retinal structure. Nevertheless, these changes seem to have no significant impact on postoperative functional outcome.
RESUMO
PURPOSE: To report on epiretinal membrane (ERM) characteristics and photoreceptor layer integrity of lamellar macular holes (LMHs) and macular pseudoholes (MPHs), and to compare with clinical course in operated and untreated eyes. METHODS: We consecutively reviewed the charts of patients with LMH and MPH between 2003 and 2013. For clinical analysis, we included 87 eyes (48 with LMH, 39 with MPH) with a minimum follow-up of 6 months. Of these, we included 64 eyes (37 with LMH, 27 with MPH) for high-resolution spectral domain optical coherence tomography analysis with examinations fulfilling the required resolution and quality of optical coherence tomography images. Epiretinal membranes were termed "typical tractional ERM" if presenting with contractive properties, or "atypical epiretinal tissue" if presenting as epiretinal material of homogeneous medium reflectivity without contractive properties. Integrity or discontinuity of the inner and outer segment (IS/OS) and the external limiting membrane (ELM) was evaluated by differentiating between "defect present" and "defect absent." RESULTS: In eyes with LMH, atypical epiretinal tissue presented in 29%, typical tractional ERMs were seen in 57%, and a combination of both in 14%. In contrast, eyes with MPH rarely presented atypical epiretinal tissue, and typical tractional ERMs were found in 89%. Comparing cases with LMH, eyes with atypical epiretinal tissue showed significantly more defects of the IS/OS and the ELM than eyes with typical tractional ERM. Both IS/OS and ELM defects correlated with a significant lower best-corrected visual acuity. Defects of the IS/OS were seen in 41% of LMH and 11% of MPH. Defects of the ELM revealed in 27% of LMH and in 11% of MPH. Operated eyes with disrupted IS/OS but intact ELM had significant better best-corrected visual acuity than eyes with defects in both layers. CONCLUSION: Atypical epiretinal tissue is related to the presence of photoreceptor layer defects and to poor visual acuity. It seems that integrity of the ELM is most important for functional recovery after surgery in both LMH and MPH. The presence of atypical epiretinal tissue in eyes with LMH may represent differences in the pathogenesis compared with MPH, and might have therapeutic implications for the proceeding with macular surgery in selected cases.
