The purpose of this study is to evaluate the macular morphological changes associated with idiopathic epiretinal membrane (iERM) using high-resolution Fourier-domain optical coherence tomography (FD-OCT), as they correlate with visual acuity and microperimetry (MP-1).
In all, 24 eyes (19 subjects) with iERM were imaged prospectively using FD-OCT with axial resolution of 4.5 μm and transverse resolution of 10 to 15 μm. MP-1 and Stratus OCT were carried out in a subset of eyes.
The mean log of the minimum angle of resolution best-corrected visual acuity (BCVA) was 0.18±0.16 (range: −0.08 to 0.48, Snellen equivalent 20/15−1 to 20/60). ERM was visualized in all 24 eyes with FD-OCT and in 17 eyes (85%) of 20 eyes imaged with Stratus OCT. Although BCVA correlated with macular thickening in the central 1 mm sub-field of the Stratus ETDRS (P=0.0005) and macular volume (central 3 mm area) on FD-OCT (P<0.0001), macular thickening on thickness map and volume correlated poorly with decrease in macular sensitivity on MP-1 (P=0.16). On FD-OCT, foveal morphological changes correlated best with decrease in BCVA, the strongest being central foveal thickness (P<0.0001). Other significant changes included blurring of the foveal inner segment–outer segment (IS–OS) junction and/or Verhoeff's membrane, vitreal displacement of foveal outer nuclear layer and foveal detachment (P<0.05). Foveal IS–OS junction disruption was seen in 25% of eyes on Stratus OCT but in none of the eyes on FD-OCT.
FD-OCT allowed improved visualization of ERM and associated foveal morphological changes that correlated best with BCVA. Macular thickening correlated weakly with decreased macular function as assessed by MP-1.
epiretinal membrane; Fourier-domain optical coherence tomography; macular morphology; Stratus OCT; microperimetry
The pathogenesis of idiopathic epiretinal membranes (iERMs), a common pathology found in retina clinics, still eludes researchers to date. Ultrastructural studies of iERMs in the past have failed to identify the cells of origin due to the striking morphologic changes of cells involved via transdifferentiation. Thus, immunohistochemical techniques that stain for the cytostructural components of cells have confirmed the importance of glial cells and hyalocytes in iERM formation. The cellular constituents of iERMs are thought to consist of glial cells, fibroblasts, hyalocytes, etc. that, in concert with cytokines and growth factors present in the vitreous, lead to iERM formation. Recently, research has focused on the role of the posterior hyaloid in iERM formation and contraction, particularly the process of anomalous PVD as it relates to iERM formation. Recent advances in proteomics techniques have also elucidated the growth factors and cytokines involved in iERM formation, most notably nerve growth factor, glial cell line-derived growth factor, and transforming growth factor β1.
To identify preoperative markers on spectral domain optical coherence tomography (SD-OCT) for residual inner limiting membrane (ILM) in epiretinal membrane (ERM) peeling.
In this retrospective case series the preoperative SD-OCTs from 119 eyes of 119 consecutive patients who underwent surgery for idiopathic ERM by a single surgeon were evaluated for markers predisposing for ILM persistence after ERM removal. ILM persistence was determined via intraoperative indocyanine green staining. The main outcome measures were correlation of central foveal thickness (CFT), ERM thickness, extent of elevated ERM and retinal folding, intraretinal cysts, and discontinuation of the ERM, with ILM persistence after ERM peeling.
The persistence of the ILM was found in 50.4% (n = 60). After Bonferroni correction for multiple testing, a greater extent of elevated ERM and thicker ERMs were associated with persistence of the ILM (p<0.005). The other parameters showed no statistically significant correlations with the persistence of the ILM (p≥0.005).
Residual ILM can be found in nearly half of the eyes after ERM peeling. A loose connection between the ERM and the retinal surface predisposes for ILM persistence. Preoperative SD-OCT is helpful in identifying risk markers for the persistence of the ILM in ERM surgery.
To determine the prevalence and risk factors associated with idiopathic epiretinal membranes (iERM) in a Chinese population aged 60 years or older in Beixinjing Blocks, Shanghai.
This population-based study consisted of 3727 participants (89.7% of the eligible). It was performed to describe the prevalence of iERM and possible demographic, systemic, and ocular factors associated with iERM. Each participant underwent a standardized interview and comprehensive ophthalmic examination. iERM was identified and graded from retinal photographs. Then, a case-control study comparing the participants with vs. without iERM was performed to further study the associations between iERM and blood biochemical test results (including fasting plasma glucose, serum creatinine, total cholesterol, and triglyceride), ocular biological parameters (including the axial length, corneal curvature, refractive diopter, intraocular press, and anterior chamber depth), and the data of optical coherence tomography.
The prevalence of iERM was 1.02%. iERM was significantly associated with diabetes (OR: 2.457; 95% CI: 1.137, 5.309) and a higher level of education (OR: 1.48; 95% CI: 1.123, 1.952). Blood biochemical test results and ocular biological parameters showed no significant differences between the iERM and control groups, whereas the incidence of posterior vitreous detachment in the iERM group was much higher than in the control group (26.5% vs. 8.8%), but this difference was not statistically significant. Moreover, the eyes with iERM had poorer visual acuity than the eyes without iERM (P<0.05).
In Beixinjing Blocks, Shanghai, iERM was relatively rare, was associated with diabetes and a higher level of education, and caused a substantial decrease in visual acuity.
To evaluate the anatomical and functional outcome in eyes with indocyanine green (ICG)-assisted idiopathic epiretinal membrane (ERM) peeling by optical coherence tomography (OCT) and multifocal electroretinogram (MFERG).
Prospective, interventional, noncomparative case series.
Twenty eyes of 20 patients with idiopathic ERM underwent pars plana vitrectomy and ICG-assisted ERM and internal limiting membrane (ILM) removal. Visual acuity (VA), OCT, and MFERG measurements were performed preoperatively and postoperatively at 1, 3, 6, and 12 months.
Best-corrected VA (BCVA) improved ≥2 Snellen lines in 70% of our patients at the 12th postoperative month. Mean VA increased from 20/100 preoperatively to 20/40 at 12 months. VA increased significantly at all postoperative examinations, compared to preoperative VA. Foveal thickness measured by OCT decreased significantly at all postoperative examinations. OCT mean values dropped from 472.3 μm preoperatively, to 249.2 μm at 12 months. Preoperative MFERG values significantly improved only at 12 months. OCT measurements and MFERG values did not correlate at any time. OCT values correlated with VA values only preoperatively while MFERG measurements correlated with VA at 12 months.
In our series of eyes with ERM surgery, OCT measurements and VA improved gradually throughout the first postoperative year, while MFERG values showed significant improvement at 12 months.
To determine the retinal thickness (RT), after vitrectomy with internal limiting membrane (ILM) peeling, for an idiopathic macular hole (MH) or an epiretinal membrane (ERM). Also, to investigate the effect of a dissociated optic nerve fiber layer (DONFL) appearance on RT.
A non-randomized, retrospective chart review was performed for 159 patients who had successful closure of a MH, with (n = 148), or without (n = 11), ILM peeling. Also studied were 117 patients who had successful removal of an ERM, with (n = 104), or without (n = 13), ILM peeling. The RT of the nine Early Treatment Diabetic Retinopathy Study areas was measured by spectral domain optical coherence tomography (SD-OCT). In the MH-with-ILM peeling and ERM-with-ILM peeling groups, the RT of the operated eyes was compared to the corresponding areas of normal fellow eyes. The inner temporal/inner nasal ratio (TNR) was used to assess the effect of ILM peeling on RT. The effects of DONFL appearance on RT were evaluated in only the MH-with-ILM peeling group.
In the MH-with-ILM peeling group, the central, inner nasal, and outer nasal areas of the retina of operated eyes were significantly thicker than the corresponding areas of normal fellow eyes. In addition, the inner temporal, outer temporal, and inner superior retina was significantly thinner than in the corresponding areas of normal fellow eyes. Similar findings were observed regardless of the presence of a DONFL appearance. In the ERM-with-ILM peeling group, the retina of operated eyes was significantly thicker in all areas, except the inner and outer temporal areas. In the MH-with-ILM peeling group, the TNR was 0.86 in operated eyes, and 0.96 in fellow eyes (P < 0.001). In the ERM-with-ILM peeling group, the TNR was 0.84 in operated eyes, and 0.95 in fellow eyes (P < 0.001). TNR in operated eyes of the MH-without-ILM peeling group was 0.98, which was significantly greater than that of the MH-with-ILM peeling group (P < 0.001). TNR in the operated eyes of the ERM-without-ILM peeling group was 0.98, which was significantly greater than that of ERM-with-ILM peeling group (P < 0.001).
The thinning of the temporal retina and thickening of the nasal retina after ILM peeling does not appear to be disease-specific. In addition, changes in RT after ILM peeling are not related to the presence of a DONFL appearance.
epiretinal membrane; macular hole; optical coherence tomography; retinal thickness; internal limiting membrane
To determine whether horizontal macular contraction caused by epiretinal membranes (ERMs) improves after surgical removal.
In this prospective, single-center, observational study, 63 consecutive patients with unilateral idiopathic ERM in one eye and no retinal disease in the fellow eye underwent pars plana vitrectomy. Fundus photography and optical coherence tomography (OCT) were performed preoperatively and at 3 months postoperatively. The area enclosed by superior and inferior major vessels from the optic disc to the fovea (area under major vessel (AUV)) and the macroscopic diverging angle (MDA) between superior and inferior major vessels were calculated using digital image analysis of fundus photographs and compared pre- and postoperatively.
AUV was significantly smaller in the eyes with ERM compared with the normal fellow eyes (P<0.001). Significant postoperative change in AUV and MDA was demonstrated after ERM removal (P<0.001). However, postoperative AUV of grade 2 and 3 ERM eyes was still significantly smaller than that of normal fellow eyes. Macular thickness differences measured with stratus OCT were positively correlated with AUV differences.
Retinal topographic changes caused by ERM improved in part after ERM removal. The improvement of topographic changes were correlated with tomographic changes detected with OCT.
epiretinal membrane; macular contraction; surgical removal
To describe a case of fine retinal striae visualized using an adaptive optics flood illuminated (AO-flood) fundus camera in a patient with vision loss from an idiopathic macular epiretinal membrane (ERM).
A case report of a 48-year-old woman with recent vision loss from ERM imaged using an AO-flood fundus camera and high resolution Fourier-domain optical coherence tomography (Fd-OCT) before and 3 months after vitrectomy.
Visual acuity improved from 20/70 to 20/20 after vitrectomy. Preoperative Fd-OCT showed severe cystoid macular edema with irregularities in the outer nuclear layer which consists of cell bodies of photoreceptors. Preoperative AO-flood en face images showed dark linear striae of approximately 10 μm width overlying the cone mosaic that improved following surgery, concurrent with improvement in visual acuity and morphologic changes on Fd-OCT.
Microstructural changes within the retinal layers resulting from macular traction from ERM can be visualized using an AO-flood fundus camera and Fd-OCT. They can appear as fine linear striae in AO-flood en face images. Further studies are needed to correlate these changes with vision loss associated with this condition.
To assess the clinical outcomes in idiopathic epiretinal membrane (ERM) patients after vitrectomy and ERM removal with or without additional indocyanine green (ICG)-assisted internal limiting membrane (ILM) peeling.
The medical records of 43 patients with an idiopathic ERM that underwent vitrectomy and ERM removal between July 2007 and April 2010 were reviewed. The patients were divided into two groups: triamcinolone-assisted simple ERM peeling only (group A, n = 23) and triamcinolone-assisted ERM peeling followed by ICG staining and peeling of the remaining internal ILM (group B, n = 20).
No difference was found between the two groups in terms of visual acuity, macular thickness, P1 amplitude or implicit time on multifocal-electroretinogram (mfERG) at six and 12 months postoperatively. In group B, ICG staining after ERM peeling demonstrated that the ILM had been removed together with the ERM in 12 eyes (60%), and all 12 eyes showed punctate retinal hemorrhages during ERM peeling. There was no recurrence of an ERM in either group.
Additional procedures involving ICG staining and ILM peeling during ERM surgery do not appear to have an additive effect on the clinical outcomes in terms of visual acuity, retinal function based on mfERG, or recurrence rate.
Double staining; Epiretinal membrane; Internal limiting membrane
Purpose. To correlate the uveitic epiretinal membrane (ERM) features using spectral-domain optical coherence tomography (SD-OCT) with visual acuity (VA). Methods. Forty-one eyes of 32 patients were included in this retrospective study. SD-OCT was performed in all patients and data were collected at the time of ERM diagnosis and at the final visit. Both best corrected visual acuity (BCVA) and ERM thickness were correlated with the morphological and clinical features. Results. Final BCVA was positively correlated with male sex (P = 0.0055) and the focal pattern of ERM attachment (P = 0.031) and negatively correlated with IS/OS photoreceptor junction disruption (P = 0.042). BVCA change showed a positive correlation with the age of ERM onset (P = 0.056) but a negative correlation with IS/OS photoreceptor disruption at the ERM diagnosis (P = 0.029) and the increase of central subfield thickness (CST) (P = 0.95). Final ERM thickness correlated with the duration of uveitis (P = 0.0023) and the duration of ERM (P = 1.15 e-05). During the follow-up, ERM thickening correlated with male sex (P = 0.042), posterior uveitis (P = 0.036), uveitis duration (P = 0.026), and broad attachment pattern (P = 0.052). Conclusions. In the uveitic ERM, VA negatively correlates with IS/OS photoreceptor junction disruption and the increase of CST. ERM thickness is influenced by longer duration of both uveitis and ERM.
To describe epiretinal membrane (ERM) features using spectral domain optical coherence tomography “SD OCT” and to delineate the three-dimensional (3D) relationship in eyes with epiretinal membrane.
Fifty-two eyes of 44 patients with ERM were classified into two groups: idiopathic ERM and secondary ERM. Posterior vitreous face was evaluated. Pattern of ERM attachment was divided into: focal and global. A 3D SD OCT system (5 μm resolution) was used for scanning. Surface maps were used to study retinal topography.
Surface maps revealed manner and direction of epiretinal traction, pattern of attachment and blood vessel involvement. In 55.8% of eyes the membrane was globally adherent to the retina. There was a significant association (p = 0.02%) between pattern of membrane attachment and etiological classification of eyes. Posterior vitreous detachment (PVD) was associated with both groups, but no significant difference in between.
Spectral domain OCT allowed better characterization of ERM including: visualization, extension, cleavage plane and zones with free edges. Surface maps revealed the topography of ERM and retina pathology. Idiopathic ERM are significantly associated with global pattern. PVD plays an important role in the pathogenesis of primary as well as secondary ERM.
Epiretinal membrane; Optical coherence tomography; Three-dimensional
Optical coherence tomography (OCT) has emerged as a powerful diagnostic aid in disorders of the vitreoretinal juncture. The purpose of this study is to determine whether OCT can be used as an additional tool for evaluating an architecture including the thickened area, and the identifiable edge of a macular epiretinal membrane (ERM), and helping us to dissect the ERM from the retinal surface more easily and safely. In two cases with ERM, the edges of the membranes were detected by OCT, and the peeling of the membrane was started at the area easily. OCT guided ERM peeling might be useful for dissecting ERM membranes without any hesitation.
optical coherence tomography; epiretinal membrane; vitrectomy
To evaluate the clinical course of visual acuity and foveal thickness in the idiopathic epiretinal membrane (ERM) after a vitrectomy with the use of triamcinolone.
We retrospectively reviewed the records of 30 patients (30 eyes) with ERM that were treated by vitrectomy from 2004 to 2008. Visual acuity and foveal thickness from optical coherence tomography imaging was obtained preoperatively and at every postoperative follow-up visit.
Visual acuity improved by two or more lines of vision in 30%, 50%, 60%, and 70%, and stayed the same within ±1 line in 47%, 50%, 40%, and 30% at one month, three months, five months, and seven months after surgery. Twenty-three percents of the subjects deteriorated by two or more lines of vision within one month after surgery. None of the subjects had reduced vision three months after surgery. Foveal thickness decreased significantly after surgery. The mean thickness was 409.7±107.9 µm before surgery and 288.6±66.1 µm seven months after surgery. Parameters which were significantly correlated with the final visual acuity included preoperative visual acuity (0.683), preoperative foveal thickness (0.544), and final foveal thickness (0.643) (p<0.005).
Foveal thickness and visual acuity improved until seven months after the vitrectomy in patients with idiopathic ERM. Preoperative visual acuity, foveal thickness, and final foveal thickness had a significant correlation with the final visual acuity.
Epiretinal membrane; Foveal thickness; Optical coherence tomography; Visual acuity; Vitrectomy
To identify visually significant spectral-domain optical coherence tomography (SD-OCT) features of epiretinal membranes (ERM) in patients with uveitis.
Retrospective cohort and cross-sectional study.
Eighty consecutive eyes with uveitis and SD-OCT– documented ERM were included. Clinical data were collected at the time of diagnosis of ERM and at the final visit. SD-OCT images at the last visit were evaluated to identify fovea and ERM configuration and structural changes. Changes of 10% and 20% in central subfield thickness between initial and last SD-OCT were calculated and correlated with visual acuity (VA). An ERM thickness map was created using validated SD-OCT grading software.
VA improved significantly in eyes with more than 12 months of follow-up (P = .03). Although inflammation activity and medical treatment methods were no different in eyes with more or less than 12 months of follow-up, 16 eyes in the subset with longer follow-up underwent cataract extraction and intraocular lens implantation. Kaplan-Meier analysis demonstrated few vision losses during the follow-up period. Change in central subfield thickness did not correlate with VA. Foveal center involvement (P < .001), focal attachment of the ERM (P = .003), and foveal inner segment and outer segment junction disruption (P = .006) were associated independently with lower VA. ERM was thinner in eyes with 20/40 or better VA (4.6 ± 0.6 μm) compared with eyes with VA of less than 20/200 (P =.02). Longer duration of ERM was associated with thicker ERM (P < .05).
In most eyes with uveitis and ERM, VA remains stable if ocular inflammation and comorbidities are addressed appropriately.
The purpose of this study is to investigate the morphological features of epiretinal membrane (ERM) in the presence or absence of a posterior vitreous detachment (PVD).
Retrospective observational comparative case series.
This study involved 34 patients in whom the vitreoretinal relationship was confirmed during vitrectomy for treatment of ERM. We analyzed demography, direction of macular folds in fundus photographs, and foveal contours assessed by optical coherence tomography (OCT) in two groups of patients, the posterior vitreous attachment (PVA) group and the PVD group.
Mean age of the 14 patients in the PVA group was 58.2±8.2 years, and that of 20 patients in the PVD group was 66.7±6.7 years (P=0.0023). Funduscopic examination revealed radiating folds in 57.1% of patients in the PVA group and 10% of patients in the PVD group, and a flat-shaped foveal contour was observed on OCT in 71.5% of patients in the PVA group and 25.0% of patients in the PVD group. Significant differences were observed between the PVA group and the PVD group in both direction of the macular folds (P<0.01) and foveal contours (P=0.028).
Patients with ERM and PVA were usually younger than 60 years. Radiating macular folds and flat foveal contour in patients with ERM are highly sensitive and specific findings indicative of PVA.
epiretinal membrane; posterior vitreous attachment; posterior vitreous detachment; retinal fold; foveal flattening; OCT
To report the preoperative best-corrected visual acuity (BCVA) and foveal thickness (FT) values that lead to a postoperative decimal BCVA of ≥1.0 after surgical removal of an idiopathic epiretinal membrane (ERM).
This is a retrospective case series of 73 eyes that underwent surgery for removal of an idiopathic ERM. All eyes had been treated by a single surgeon using a 25-gauge transconjunctival sutureless vitrectomy and indocyanine green-assisted internal limiting membrane peel. The BCVA and FT were measured at baseline and 6 months postoperatively.
A postoperative decimal BCVA ≥ 1.0 was obtained in eyes with a preoperative decimal BCVA ≥ 0.3 but not in those with a preoperative decimal BCVA ≤ 0.2. The incidence of obtaining a postoperative decimal BCVA ≥ 1.0 was significantly (P = 0.002) higher in eyes with a preoperative decimal BCVA ≥ 0.5 (50%) than in eyes with a preoperative decimal BCVA < 0.5 (11%). Additionally, a postoperative decimal BCVA of ≥ 1.0 was obtained in 51% of the eyes that had a preoperative FT < 400 μm, compared with only 21% of eyes with a preoperative FT ≥ 400 μm (P = 0.01). The incidence of obtaining a postoperative decimal BCVA ≥ 1.0 was significantly higher in eyes with preoperative decimal BCVA ≥ 0.5 and FT < 400 μm (60%) than in eyes with preoperative decimal BCVA ≥ 0.5 and FT ≥ 400 μm (20%; P = 0.03) or preoperative BCVA < 0.5 and FT ≥ 400 μm (7%; P < 0.001).
These findings indicate that eyes with both preoperative BCVA ≥ 0.5 and FT < 400 μm have a significantly better chance of obtaining a postoperative decimal BCVA ≥ 1.0 following idiopathic ERM removal.
25-gauge vitrectomy; optical coherence tomography; epimacular membrane; epiretinal membrane; visual acuity; foveal thickness
To examine the ultrastructural correlates of spectral-domain optical coherence tomography (SD-OCT) findings in patients with vitreomacular traction (VMT).
Observational case series.
Retrospective analysis of six eyes of consecutive patients who underwent vitrectomy surgery for VMT was performed in this single-center, noncomparative study. One patient had a concurrent macular hole. Preoperative assessment included SD-OCT examination with 3-dimensional image reconstruction. During surgery the vitreous cone was dissected from the vitreous body using scissors, then removed from the surface of the retina with a combination of sharp dissection and peeling, and subsequently submitted for histologic and transmission electron microscopic processing.
SD-OCT showed prominent vitreal-foveal adhesion in all six eyes. Each eye had an epiretinal membrane (ERM) under the detached perifoveal posterior vitreous detachment. In all eyes this ERM appeared to course up the cone of attached vitreous and along the back surface of the posterior vitreous face. Ultrastructural analysis showed fibrocellular proliferations in the vitreous specimens in all six cases, which included retinal pigment epithelium (RPE) cells (five eyes), fibrocytes (four eyes), and macrophages (three eyes).
The adhesion between the vitreous and fovea in vitreomacular traction syndrome is accompanied by fibrocellular proliferation along the exposed surfaces of the inner retina and the posterior surface of the vitreous. This fibrocellular proliferation may augment the adhesion between the vitreous and fovea, and may account for the prominent OCT signal seen along the posterior surface of the vitreous in these cases.
It is widely accepted that intravitreous levels of erythropoietin (Epo) are elevated in patients with ischaemic retinal diseases such as proliferative diabetic retinopathy (PDR). The aim of this study was to examine the expression of Epo and the Epo receptor (EpoR) in epiretinal membranes with and without diabetes.
Eighteen epiretinal membranes (PDR (n = 10), idiopathic epiretinal membranes (IERMs) without diabetes (n = 4) and inner limiting membranes (ILMs) (n = 4)) were obtained during pars plana vitrectomy. Formalin‐fixed and paraffin‐embedded tissues were examined by immunohistochemistry with anti‐Epo and EpoR antibodies.
The histopathological findings demonstrated that PDR membranes consisted of a variety of endothelial cells forming a microvascular cavity with red blood cells and non‐vascular stromal mononuclear cells. Membranous and cytoplasmic immunoreactivity for EpoR was strongly detected in endothelial cells and stromal cells in all PDR patients. Although microvessels were not observed in IERMs and ILMs, immunoreactivity for EpoR was noted in the cellular component of IERMs, and was weakly detected in ILMs. Epo was not expressed in any membrane.
EpoR was strongly expressed in microvessels of all PDR membranes. The in vivo evidence in this study suggests that Epo in the vitreous binds to EpoR in PDR membranes, which subsequently leads to the proliferation of new retinal vessels. EpoR immunoreactivity in non‐vascular stromal cells in PDR membranes, and IERMs and ILMs might be indirectly correlated with ischaemia.
To evaluate the functional and morphological outcomes of postoperative systemic steroid therapy after successful macular surgery in eyes with macular edema due to idiopathic macular epiretinal membranes (ERMs).
Prospective, randomized, investigator-masked, controlled clinical study.
Twenty-eight patients scheduled for 23-gauge vitrectomy combined with ERM and inner limiting membrane (ILM) peeling for macular edema due to ERM were included in this single center trial. Patients were randomized to receive oral steroid therapy (Prednisolone, 100 mg per day for 5 days) or no oral steroid (control group) after surgery. Main outcome measures included best corrected visual acuity (BCVA; Early Treatment Diabetic Retinopathy Study), central retinal thickness (CRT), retinal volume (RV), and macular morphology as determined by spectral domain optical coherence tomography (SD-OCT, Cirrus). Examinations were carried out preoperatively and at week 1, at months 1 and 3, postoperatively.
At month 3, mean BCVA improved to a eight-letter gain in each study group (P<0.01 compared with baseline for both groups), showing no statistically significant difference between both the groups (P=0.19). Morphologically, retinal surface folds resolved within 1 month after surgery in both treatment groups, followed by a progressive recovery of retinal layer integrity and a statistical significant (P<0.01) decrease in CRT and RV without significant differences between both groups (P=0.62, P=0.13, respectively, ANOVA between the groups).
The early postoperative use of systemic steroid treatment after successful vitrectomy combined with ERM and ILM peeling does not seem to improve significantly the anatomic and functional outcomes in eyes with ERM.
epiretinal membrane; macular surgery; systemic steroid therapy; optical coherence tomography
To describe the evaluation of optical coherence tomography (OCT) scans in the Muliticenter Uveitis Steroid Treatment (MUST) trial and report baseline OCT features of enrolled participants.
Time domain OCTs acquired by certified photographers using a standardized scan protocol were evaluated at a Reading Center. Accuracy of retinal thickness data was confirmed with quality evaluation and caliper measurement of centerpoint thickness (CPT) was performed when unreliable. Morphological evaluation included cysts, subretinal fluid,epiretinal membranes (ERMs),and vitreomacular traction.
Of the 453 OCTs evaluated, automated retinal thickness was accurate in 69.5% of scans, caliper measurement was performed in 26%,and 4% were ungradable. Intraclass correlation was 0.98 for reproducibility of caliper measurement. Macular edema (centerpoint thickness ≥ 240um) was present in 36%. Cysts were present in 36.6% of scans and ERMs in 27.8%, predominantly central. Intergrader agreement ranged from 78 − 82% for morphological features.
Retinal thickness data can be retrieved in a majority of OCT scans in clinical trial submissions for uveitis studies. Small cysts and ERMs involving the center are common in intermediate and posterior/panuveitis requiring systemic corticosteroid therapy.
The aim of the current study was to evaluate macular function before and after surgery for idiopathic epiretinal membranes with internal limiting membrane (ILM) peeling by means of multifocal electroretinography (ERG). Eighteen eyes of 18 patients who underwent vitrectomy with ILM removal were included. Best corrected visual acuity, optical coherence tomography (OCT), and multifocal electroretinography were assessed prior to surgery, and 3 and 12 months after surgery. All surgical samples were obtained and confirmed inclusion of an ILM by electron microscopy. Visual acuity and the central foveal thickness by OCT improved significantly 3 months postoperatively, with gradual recovery by 12 months. Preoperatively, only the P1 amplitude in rings 1 and 2 were decreased compared with the normal fellow eyes (P < 0.01). Three and 12 months after surgery, the P1 amplitude in rings 1 and 2 were decreased compared with the preoperative P1 amplitudes, but without significance. The photoreceptor status by OCT was related to the N1 amplitude before and after surgery. Although visual acuity and macular edema were improved after surgery, macular function, as indicated by multifocal ERG, had limited recovery at 12 months.
epiretinal membrane; macular function; multifocal electroretinography
To present the clinical spectrum of lamellar macular defects and describe the different subtypes based on their optical coherence tomography (OCT) configuration and visual prognosis.
The retrospective observational case series reviewed OCT scans of 92 eyes with lamellar macular defects. Lamellar macular defects were categorised into subtypes of macular pseudohole (MPH), lamellar macular hole (LMH) and foveal pseudocyst (FP) according to their OCT morphology. The defects were quantitatively characterised in terms of base diameter, depth and central foveal thickness, and examined for the presence of associated epiretinal membranes (ERM).
Visual acuity (VA) was significantly correlated with the central foveal thickness and depth of the lamellar defect. MPH was associated with better VA compared with LMH and FP. MPH was of a smaller base diameter and had a greater central foveal thickness than that of LMH and FP. Fifty-per cent of all lamellar defects had an associated ERM.
Different profiles of lamellar macular defects were characterised and quantified by OCT. Deeper and wider lamellar defects were associated with poorer visual outcome. Such objective parameters lamellar macular defects are of value when explaining to patients regarding their decreased acuity. Future prospective investigations are required to study the natural history of lamellar defects of different aetiology and surgical indications.
To compare retinal surgeons’ recommendations for management of epiretinal membranes (ERM) and vitreomacular traction syndrome (VMT) based on clinical examination alone, with management based on examination supplemented by optical coherence tomography (OCT).
A prospective, masked clinical case series was conducted. Surgeons first assessed, on the basis of clinical examination only, whether ERM, VMT, or macular edema was present, questionably present, or absent and made a provisional management recommendation. The retina specialist then reviewed the OCT images, determined the presence or absence of ERM, VMT, or associated macular edema, and made a final management recommendation.
Eighty-four eyes of 73 patients were examined. ERM was identified in 66 (78.6%) of 84 using clinical examination compared to 72 (85.7%) of 84 using OCT (P = .06). VMT was identified in five (6%) of 84 using clinical examination compared to 18 (21.4%) of 84 using OCT (P < .005). Macular edema was identified in 57 (67.9%) of 84 using clinical examination compared to 70 (83.3%) of 84 using OCT (P =.003). Surgical intervention was recommended in 33 cases: 19 (57.6%) based on clinical examination alone and 14 (42.4%) based on the combination of clinical examination and OCT findings.
OCT is more sensitive than clinical examination in detecting ERM, VMT, and associated macular edema. OCT influenced the recommendation for surgical intervention in 42.4% of patients scheduled for surgery.
We report intensely staining epiretinal membrane (ERM) with Brilliant Blue G (BBG) under air for two minutes. ERM peeling was performed in 21 cases. After removal of posterior hyaloid, 0.2 mL BBG was first applied on the macula, to stain ERM under air conditions for 2 minutes. Internal limiting membrane (ILM) was intensely stained and peeled in all cases following ERM removal. In 4 cases, the ERM was also observed to be intensely stained with BBG and peeled with an ILM forceps. Postoperatively, the ganglion cell layer thickness was lower in three of the cases, however VA improved in all cases and multifocal electroretinogram revealed no toxicity. Light microscopy of ERM revealed masses of cells whereas; the ILM did not. The increased staining characteristics of ERM and ILM may be resulted from longer contact time of BBG under air pressure.
To study the ability of volumetric spectral domain optical coherence tomography (SD-OCT) to perform quantitative measurement of the choroidal vasculature in vivo.
Choroidal vascular density and vessel size were quantified using en face choroidal scans from various depths below the retinal pigment epithelium (RPE) in 58 eyes of 58 patients with either epiretinal membranes (ERM), early age-related macular degeneration (AMD), or reticular pseudo-drusen (RPD). For each patient, we used the macular volume scan (6×6 mm cube) for vessel quantification, while high-definition (HD) cross-section raster scans were used to qualitatively assess vascularity of the choroidal sub-layers, and measure choroidal thickness.
Of the 58 patients, more were female (66% versus 34% male), of whom 14 (24%) had ERM, 11 (19%) early AMD, and 33 (57%) RPD. Compared to intact choriocapillaris in all ERM (100%), none of the RPD and only 5/11 (45%) early AMD eyes had visible choriocapillaris on either cross section or C-scans (p-value<0.001). When comparing select regions from the most superficial C-scans, early AMD group had lowest vascular density and RPD had highest (p-value 0.04). Qualitative evaluation of C-scans from all three groups revealed a more granular appearance of the choriocapillaris in ERM versus increased stroma and larger vessels in the RPD eyes.
SD-OCT can be used to qualitatively and quantitatively assess choroidal vascularity in vivo. Our findings correlate to previously reported histopathologic studies. Lack of choriocapillaris on HD cross-sections or C-scans in all RPD and about half of early AMD eyes suggests earlier choroidal involvement in AMD and specifically, RPD.