The role of multimodal imaging in characterization and monitoring of choroidal neovascularization secondary to angioid streaks.

BACKGROUND: To characterize and monitor choroidal neovascularisation (CNV) secondary to angioid streaks (AS) using multimodal imaging and to compare the results with conventional fluorescein angiography (FA). METHODS: A total of 11 eyes with CNV secondary to AS were included in this retrospective study. Multimodal morphological and functional assessment, including spectral-domain optical coherence tomography (SD-OCT), spectral-domain optical coherence tomography angiography (SD-OCTA), and fundus autofluorescence (FAF), were used to assess for evidence of CNV activity and compared with conventional FA. Morphological features of CNV were analyzed and treatment was continuously monitored using SD-OCT and SD-OCTA. RESULTS: Our results showed that SD-OCTA provided reliable results for the detection of secondary CNV in AS that were comparable to conventional FA. With SD-OCTA, a total of 13 CNVs were detected in 11 eyes and analyzed by means of outer retinal choriocapillaris depth (ORCC) segmentation and the corresponding B-scans. Twelve of the 13 CNVs were classified as active and therefore required treatment. For treatment monitoring during intravitreal therapy (IVT), SD-OCTA was found to be a valuable diagnostic tool over a mean follow-up of 76 weeks. CONCLUSIONS: Our study demonstrates that SD-OCTA can be routinely used to identify ill-defined CNV without dye-based angiography, especially in cases of CNV secondary to AS, where Bruch's membrane (BM) defects limit the diagnostic value of FA. Our results showed that non-invasive multimodal imaging facilitates sufficient CNV monitoring and treatment guidance. Further studies are warranted to provide more evidence in this rare retinal disease.

Ultrastructural Details of Epiretinal Membrane Foveoschisis.

INTRODUCTION: The aim of this study was to describe differences in the vitreomacular interface (VMI) in idiopathic epiretinal membrane (ERM) foveoschisis compared to macular pseudohole (MPH) and lamellar macular hole (LMH). METHODS: We analysed surgically excised epiretinal material and internal limiting membrane (ILM) specimens obtained from 16 eyes of 16 patients with ERM foveoschisis (6 eyes), MPH (5 eyes), and LMH (5 eyes) during standard pars plana vitrectomy (PPV) with membrane peeling. The three entities were classified according to the newly introduced optical coherence tomography (OCT) terminology. Transmission electron microscopy (TEM) was used to describe the ultrastructural features. RESULTS: We found fibrocellular epiretinal tissues in all samples analysed. However, the cell and collagen composition of the VMI differed between groups. Eyes with ERM foveoschisis were characterized by a higher number of cells, multilayered membranes, and thick strands of vitreous collagen embedding the major cell types of myofibroblasts compared to MPH. Eyes with MPH also showed a predominance of myofibroblasts, but these were located directly on the ILM with no collagen between the cells and the ILM. Eyes with LMH showed a thick, multilayered epiretinal proliferation consisting mainly of non-tractional glial cells, corresponding to hypodense epiretinal proliferation on OCT. Eyes with ERM foveoschisis and MPH were more likely to have incomplete PVD compared to LMH in terms of posterior hyaloid status. DISCUSSION/CONCLUSION: Tractional ERMs in eyes with ERM foveoschisis and MPH differ in their ultrastructure. The main difference is in the amount and topographical distribution of vitreous collagen. However, the epiretinal cell types are predominantly myofibroblasts in both entities. This highlights the importance of distinguishing ERM foveoschisis from both MPH and LMH in terms of pathogenesis and surgical peeling procedures.

PORES OF THE INTERNAL LIMITING MEMBRANE: A Common Finding in Vitreomaculopathies.

PURPOSE: To describe presence and distribution of pores of the inner limiting membrane (ILM) in eyes with vitreomaculopathies. METHODS: Inner limiting membrane specimens were harvested from 117 eyes of 117 patients during vitrectomy with membrane peeling from eyes with vitreomacular traction syndrome, idiopathic and secondary epiretinal gliosis, and idiopathic full-thickness macular hole. All specimens were processed as flat-mounts for immunocytochemistry and examined by phase-contrast, interference, and fluorescence microscopy. Demographic and clinical data were correlated. RESULTS: Inner limiting membrane pores were found in all vitreomaculopathies. They were identified in 47 (40.2%) of 117 eyes being most evident with antilaminin. In eyes with full-thickness macular hole >400 µ m, pores were seen in more than half of all eyes. They occur as numerous and uniformly distributed defects of the flat-mounted ILM with a mean diameter of 9.5 ± 2.4 µ m. Edges of ILM pores are round with an irregular contour and no specific cellular pattern. Pores were distinguished from retinal vessel thinning and iatrogenic artefacts. CONCLUSION: Contrary to previous reports, ILM pores are a common finding in vitreomaculopathies easily visible with antilaminin staining. Further studies are needed to clarify whether their presence correlates with differences in disease progression or imaging before and after vitrectomy with ILM peeling.

Long-Term Results of Adjunct Autologous Platelet-Rich Plasma in Lamellar Macular Hole Surgery Showing Lasting Restoration of Foveal Anatomy.

The aim of this study was to evaluate the long-time results of highly concentrated autologous platelet-rich plasma (PRP) used as an adjunct in lamellar macular hole (LMH) surgery. Nineteen eyes of nineteen patients with progressive LMH were enrolled in this interventional case series, on which 23/25-gauge pars plana vitrectomy was performed and 0.1 mL of highly concentrated autologous platelet-rich plasma was applied under air tamponade. Posterior vitreous detachment was induced, and the peeling of tractive epiretinal membranes, whenever present, was performed. In cases of phakic lens status, combined surgery was carried out. Postoperatively, all patients were instructed to remain in a supine position for the first two postoperative hours. Best-corrected visual acuity (BCVA) testing, microperimetry, and spectral domain optical coherence tomography (SD-OCT) were carried out preoperatively and at minimum 6 months (in median 12 months) postoperatively. Foveal configuration was postoperatively restored in 19 of 19 patients. Two patients who had not undergone ILM peeling showed a recurring defect at 6-month follow-up. Best-corrected visual acuity improved significantly from 0.29 ± 0.08 to 0.14 ± 0.13 logMAR (p = 0.028, Wilcoxon signed-rank test). Microperimetry remained unchanged (23.38 ± 2.53 preoperatively; 23.0 ± 2.49 dB postoperatively; p = 0.67). No patients experienced vision loss after surgery, and no significant intra- or postoperative complications were observed. Using PRP as an adjunct in macular hole surgery significantly improves morphological and functional outcomes. Additionally, it might be an effective prophylaxis to further progression and also the formation of a secondary full-thickness macular hole. The results of this study might contribute to a paradigm shift in macular hole surgery towards early intervention.

Optimal Patient Adherence and Long-Term Treatment Outcomes of Neovascular Age-Related Macular Degeneration in Real-Life.

PURPOSE: To report on long-term real-life outcomes of anti-vascular endothelial growth factor (anti-VEGF) therapy in neovascular age-related macular degeneration (nAMD) with optimal patient adherence. METHODS: For this retrospective monocenter study, we identified 3217 eyes of 2793 patients that received a minimum of three intravitreal anti-VEGF injections for nAMD therapy between 2006 and 2014 at the University Eye Hospital Munich. From those, we included eyes with treatment-naïve nAMD, follow-up (FU) of ≥60 months and continuous adherence during FU. Primary measures were corrected visual acuity (VA), number of injections and visits as well as treatment regimen. RESULTS: We included 161 eyes of 125 patients with a mean FU of 8.0 ± 2.3 years. Mean VA at baseline was 60.1 letters (Snellen equivalent, 20/63). After the third year, mean VA declined constantly by 2-3 letters per year. After 5 and 8 years, 26.1% and 42.1% had lost at least 3 lines from baseline. Mean cumulative number of injections was 5.3 after the first year, and 23.9, 38.1, 48.5 after 5, 8, and 10 years. "Treat and extent" regimen with higher injection frequency correlated with better function. At time of last FU, 69.8% of eyes were under active treatment. Eyes with ≥70 letters at baseline correlated with better VA at the end of FU. CONCLUSIONS: Despite optimal patient adherence, visual function declined progressively in real-life nAMD therapy over long-term. The highest impact on treatment success is given by an early treatment start with individual but intensive anti-VEGF therapy.

Improving morphological outcome in lamellar macular hole surgery by using highly concentrated autologous platelet-rich plasma.

PURPOSE: To evaluate the use of highly concentrated autologous platelet-rich plasma (PRP) in lamellar macular hole (LMH) surgery with regard to function and morphology. METHODS: We included 12 eyes of 12 patients with progressive LMH in this interventional case series. After 23/25-gauge pars plana vitrectomy, 0.1ml highly concentrated autologous platelet-rich plasma was applied under air tamponade. Induction of posterior vitreous detachment and peeling of tractive epiretinal membranes were performed whenever present. Phacovitrectomy was undertaken in cases of phakic lens status. Postoperatively, all patients were instructed to rest in a supine position for the first two postoperative hours. Best-corrected visual acuity (BCVA) testing, microperimetry, spectral-domain optical coherence tomography (SD-OCT), and fundus photography were carried out preoperatively and 6 months postoperatively. RESULTS: Foveal configuration was restored in 10 of 12 patients (83.3%) at 6 months postoperatively. Two patients who had not undergone ILM peeling showed a recurring defect at 6-month follow-up. Best-corrected visual acuity improved significantly from 0.29 ± 0.08 to 0.14 ± 0.13 logMAR (Wilcoxon: p=0.028). Microperimetry remained unchanged (23.38 ± 2.53 preoperatively; 23.0 ± 2.49 dB postoperatively; p=0.67). No patient experienced vision loss after surgery, and no significant intra- or postoperative complications occurred. CONCLUSION: The application of PRP in the surgical therapy of LMH results in good morphological and functional outcomes. Additional peeling of the ILM seems to be mandatory when using PRP to prevent the recurrence of LMH. Strict postoperative supine positioning for 2 h avoids PRP dislocation. Larger sample sizes are needed to confirm the results.

CENTRAL POSTERIOR LENS CAPSULE USED INSTEAD OF AN INVERTED INTERNAL LIMITING MEMBRANE FLAP: A CLINIC-PATHOLOGICAL CASE REPORT.

PURPOSE: To present immunocytochemical characterization of a surgically excised central posterior lens capsule (PLC) that was transplanted to close a secondary refractory full-thickness macular hole (FTMH) as an epiretinal flap. For comparison, tissue of both an unaffected internal limiting membrane and unexposed PLC was processed. METHODS: Clinical-pathological case report. RESULTS: We report of a 38-year-old patient who underwent pars plana vitrectomy (PPV) with PLC tissue for patching secondary FTMH and silicone oil tamponade after tractional retinal detachment. The PLC was peeled off during a vitrectomy 1 year after positioning. For immunocytochemistry, the removed PLC was prepared as flat mount and showed a positive immunofluorescence of the Müller cells marker glutamine synthetase and for vimentin. The microglia marker IBA and the neuroprotective neurotrophic marker glia cell-derived neurotrophic factor were tested positive too. There was no immunoreactivity of cellular retinaldehyde-binding protein and glial fibrillary acidic protein. In comparison, tissue of a control internal limiting membrane that was obtained during standard FTMH surgery showed few single cells that were likewise positive for glutamine synthetase, glia cell-derived neurotrophic factor, and IBA. The control specimen of unexposed PLC showed rarely cells that were without positive immunostaining for the tested markers. CONCLUSION: Our analysis revealed positive immunoreactivity of macroglia and microglia cells of the PLC tissue that was used to patch a refractory FTMH. Similar immunostaining of PLC material and internal limiting membrane suggests the PLC transplantation as an alternative treatment option for refractory FTMH.

Cell composition at the vitreomacular interface in traumatic macular holes.

PURPOSE: To describe characteristics of the vitreomacular interface (VMI) in traumatic macular holes (TMH) compared to idiopathic macular holes (IMH) using immunofluorescence and electron microscopy, and to correlate with clinical data. METHODS: For immunocytochemical and ultrastructural analyses, premacular tissue with internal limiting membrane (ILM) and epiretinal membrane (ERM) was harvested during vitrectomy from 5 eyes with TMH and 5 eyes with IMH. All specimens were processed as flat mounts for phase-contrast microscopy, interference and fluorescence microscopy, and transmission electron microscopy (TEM). Primary antibodies were used against microglial and macroglial cells. Clinical data was retrospectively evaluated. RESULTS: Surgically excised premacular tissue of eyes with TMH showed a less pronounced positive immunoreactivity for anti-glutamine synthetase, anti-vimentin and anti-IBA1 compared to eyes with IMH. Cell nuclei staining of the flat-mounted specimens as well as TEM presented a lower cell count in eyes with TMH compared to IMH. All detected cells were found on the vitreal side of the ILM. No collagen fibrils were seen in specimens of TMH. According to patients' age, intraoperative data as well as spectral-domain optical coherence tomography (SD-OCT) analysis revealed an attached posterior vitreous in the majority of TMH cases (60%), whereas all eyes with IMH presented posterior vitreous detachment. CONCLUSION: The vitreomacular interface in TMH and IMH shows significant differences. In TMH, glial cells are a rare finding on the vitreal side of the ILM.

Highly Concentrated Autologous Platelet-Rich Plasma Restores Foveal Anatomy in Lamellar Macular Hole Surgery.

BACKGROUND: Lamellar macular holes (LMHs) are an entity of a progressive disease in which the efficacy of the therapy of choice, vitrectomy, seems to be reduced. It is unknown whether highly concentrated autologous platelet-rich plasma (PRP) is of value in the therapy of LMHs. The purpose of this study was to gauge the potential of highly concentrated PRP to restore foveal anatomy in LMH surgery. PATIENTS AND METHODS: In this interventional case series, eight eyes of eight patients with progressive LMH were included. All patients underwent a 23-gauge pars plana vitrectomy with induction of a posterior vitreous detachment and peeling of tractive epiretinal membranes whenever present. Under air tamponade, 0.1 mL of highly concentrated autologous PRP was applied. Subsequently, a gas or air tamponade was performed. All patients were instructed to rest in the supine position for the first 1 to 2 postoperative hours. Best-corrected visual acuity (BCVA) testing, microperimetry, spectral-domain optical coherence tomography (SD-OCT) and fundus photography were performed prior to and 3 months after surgery. RESULTS: SD-OCT showed closure of the macular defect with restoration of a normal foveal configuration in all (8 of 8) patients 3 months postoperatively. BCVA improved significantly, from 0.28 ± 0.08 to 0.12 ± 0.14 logMAR (Wilcoxon: p = 0.03). Microperimetry remained unchanged (24.13 ± 1.96 vs. 23.7 ± 1.54 dB; p = 0.46). No clinically significant intra- or postoperative complications were observed. CONCLUSION: The use of highly concentrated PRP enables excellent anatomical and functional outcomes in the surgical therapy of LMH. Further prospective comparative trials are warranted to compare this promising technique with existing surgical strategies.

Overcoming barriers of retinal care delivery during a pandemic-attitudes and drivers for the implementation of digital health: a global expert survey.

BACKGROUND/AIMS: The SARS-CoV-2 pandemic has imposed barriers to retinal care delivery worldwide. In this context, retinal services are exploring novel ways to ensure access to healthcare. METHODS: We conducted a worldwide survey among retinal specialists between March 31, 2020 and April 12, 2020. The expert survey was developed on the basis of focus group discussions involving retinal specialists and literature searches. It included 44 questions on alternative ways of care provision including digital health domains such as teleophthalmology, home monitoring or decentralised patient care. RESULTS: 214 retinal experts participated in the survey, of which 120 (56.1%) had more than 15 years of experience in ophthalmology. Most participants were clinicians (n=158, 73.9%) practising in Western Europe (n=159, 74%). In the majority of institutions, teleophthalmology, home monitoring and decentralised patient care have not been implemented before the pandemic (n=46, 21.8.1%; n=64, 29.9%; n=38, 19.1%). During the pandemic, the use of teleophthalmology and home monitoring increased significantly (n=105, p<0.001; n=90, p<0.001). In the subgroup of institutions reporting no teleophthalmology service before and implementing a service during the pandemic (34/70, 48.6%), reimbursement was the sole significant parameter (OR 9.62 (95% CI 2.42 to 38.16); p<0.001). CONCLUSION: Digital health is taking the centre stage tackling unpreceded challenges of retinal care delivery during the SARS-CoV-2 pandemic and may sustainably change the way we practice ophthalmology.

Comparison of Vitreomacular Interface Changes in Myopic Foveoschisis and Idiopathic Epiretinal Membrane Foveoschisis.

PURPOSE: To compare characteristics of the vitreomacular interface (VMI) in myopic foveoschisis (mFS) and idiopathic epiretinal membrane foveoschisis (iERM-FS), and to correlate with optical coherence tomography and clinical data. DESIGN: Clinicopathologic study. METHODS: Epiretinal membrane and internal limiting membrane (ILM) specimens were removed from eyes with mFS (5 eyes) and iERM-FS (5 eyes). Harvested tissue was processed for immunocytochemistry and prepared by ultrathin series sectioning for transmission electron microscopy. Cell and collagen compositions were compared and correlated with clinical data. RESULTS: All eyes presented fibrocellular membranes irrespective if associated with mFS or iERM-FS. Cell and collagen types and distribution on the vitreal side of the ILM were similar in both groups, consistent with presence of tractional membranes on optical coherence tomography images. Immunostaining of all specimens were positive for glial cells, microglia, and hyalocytes. Electron microscopy revealed evidence of epiretinal cell multilayers with masses of vitreous collagen and signs of vitreous remodeling in both groups. Three eyes with mFS but none of the eyes with iERM-FS showed massive thinning of the ILM with prominent retinal undulations and presence of retinal nerve fiber layer fragments. CONCLUSION: Whereas fibrocellular components of premacular tissue in mFS are similar to iERM-FS, pathologic abnormalities of the ILM were exclusively present in high myopia. Although peeling of the ILM appears important to completely remove tractional components of the VMI, histopathologic findings emphasize the risk for retinal damage in these highly myopic eyes, indicating that individual preoperative assessment and modification of surgical techniques require further investigation.

Premacular Cells as Source of Neurotrophic Factors in Idiopathic Macular Holes.

Purpose: To describe the presence of neurotrophic growth factors and histopathologic characteristics of internal limiting membrane (ILM) specimens obtained from large idiopathic full-thickness macular holes (FTMH). Methods: In 24 eyes of 24 patients with FTMH of diameter >400 µm, ILM specimens were harvested directly at the edge surrounding the macular hole during vitrectomy with peeling. We performed interference and phase contrast microscopy of flat mounts followed by immunostaining and transmission electron microscopy. Primary antigens directed against neurotrophic growth factors as well as antigens to glial and ganglion cells were used. Topographic relationship of cells and collagen was demonstrated by serial ultrathin sectioning. Results: Immunofluorescence microscopy demonstrated the presence of glial-derived neurotrophic factor and ciliary neurotrophic factor. Expression of vimentin, glial fibrillary acidic protein (GFAP), neurofilament, calretinin, and melanopsin was seen positive too. Cellular retinaldehyde-binding protein was seen positive in half of the specimens. Co-localisation of anti-GFAP as well as anti-vimentin with neurotrophic factors was found. Electron microscopy revealed cells exclusively on the vitreal side of the ILM. Cell fragments on the retinal side were rarely seen. Conclusion: In large FTMH, ILM specimens present positive immunolabelling of neurotrophic factors. The co-localization with macroglial cell markers suggests a premacular cell composition as a source of the neurotrophic factors. Ultrastructurally, premacular cells were found on the vitreal side of the ILM and not within the collagen network of the ILM itself.

[Lamellar macular holes : Morphological characteristics and treatment success]. / Lamelläre Makuladefekte : Morphologische Besonderheiten und therapeutischer Erfolg.

BACKGROUND: In recent years the high resolution of optical coherence tomography (SD-OCT) has led to a more exact and detailed imaging of different morphological types of lamellar macular holes (LMH). This resulted in new knowledge on the pathogenesis, morphology and progression of the disease; however, this also resulted in a lack of clarity in the terminology and in particular led to uncertainty in the treatment of these patients in clinical practice. OBJECTIVE: This article gives an overview on the morphological characteristics and treatment indications for LMH with the aim of enabling a clear differentiation compared to other morphological alterations in traction macular pathologies. MATERIAL AND METHODS: The evaluation is based on the current literature and own study data from the Department of Ophthalmology at the University of Munich, Germany. RESULTS: In eyes with LMH different morphological forms can be seen in SD-OCT. In addition to the known diagnostic criteria of irregular foveal contour, intraretinal splitting and defect of the inner foveal layers, the occurrence and characteristics of epiretinal tissue as well as the occurrence of photoreceptor layer defects can be evaluated. CONCLUSION: Further development of imaging techniques, such as SD-OCT led to improved visualization of different types of LMH. Decisions on treatment should be based on subjective complaints, best corrected visual acuity (BCVA), the clinical course, the presence of defects of the ellipsoid zone, occurrence and characteristics of epiretinal tissue. In cases of progression of symptoms and/or traction by the epiretinal tissue, an early surgical procedure has a good prognosis for functional and anatomical rehabilitation.

Premacular Cell Proliferation Profiles in Tangential Traction Vitreo-Maculopathies Suggest a Key Role for Hyalocytes.

PURPOSE: To compare immunocytochemical and ultrastructural features of premacular tissue surgically removed from eyes with tangential traction vitreo-maculopathies. METHODS: By spectral-domain optical coherence tomography (SD-OCT), premacular tissue was differentiated into premacular proliferation and premacular membrane (PMM). Specimens were harvested during vitrectomy from 10 eyes with macular pucker, lamellar macular hole (LMH) and full-thickness macular hole, and prepared for immunocytochemistry and transmission electron microscopy. RESULTS: All specimens showed positive autofluorescence consistent with the yellow colour of peeled tissue. Glial cells were predominantly positive in premacular proliferation. Hyalocytes were the main cell type in PMM. Electron microscopy revealed densely packed premacular glial cells neighbouring hyalocytes and vitreous collagen strands. Myofibroblasts with features indicative of contractile properties were found in PMM, exclusively. Cell composition of premacular proliferation was free of contractile elements. CONCLUSION: All three types of vitreo-maculopathy have similar cell constituents in their premacular tissue. Cell population of premacular proliferation is not unique for LMHs. Corresponding to SD-OCT, electron microscopy demonstrates hyalocytes and vitreous collagen in PMMs both directly adjacent to the cellular complex of premacular proliferation. Study results point to the vitreous as one important pathogenic player potentially driving the degenerative cellular process at the vitreoretinal interface in tangential traction vitreo-maculopathies.

Lamellar hole-associated epiretinal proliferation presenting with perifoveal exudative vascular anomalous complex.

PURPOSE: Spectral-domain optical coherence tomography (SD-OCT) commonly reveals lamellar-hole-associated epiretinal proliferation (LHEP) as an avascular homogenous layer of premacular material with medium reflectivity, as recently described in various traction maculopathies, mostly in lamellar macular holes (LMH). We have used multimodal imaging to examine a patient suffering from unilateral advanced atrophic LMH presenting LHEP with perifoveal exudative vascular anomalous complex (PEVAC) and intra-LHEP edema fluctuating under anti-vascular endothelial growth factor (anti-VEGF) therapy. OBSERVATION: A 77-year-old male presented with decreased vision in the left eye attributable to longstanding LMH. He complained of worsening symptoms for six months. Whereas SD-OCT showed classic tractional epiretinal gliosis in the right eye, the left eye exhibited atrophic LMH and a significant amount of LHEP containing hyperreflective round lesions and hyporeflective cystoid spaces. Fluorescein/indocyanine green angiography demonstrated PEVAC with large anomalous vessels and exudation. OCT angiography revealed abnormal vessels originating from the deep retinal plexus. After anti-vascular endothelial growth factor (anti-VEGF) therapy, the intraretinal edema seemed to decrease. CONCLUSIONS AND IMPORTANCE: Perifoveal exudative vascular anomalous complex can occur in eyes with advanced LMHs causing edema inside LHEP. Pathologic vessels appear to originate from the deep retinal plexus. Given that LHEP formation is proposed to be a glial-cell-driven process, Müller cells may play a decisive role in the pathogenesis of the presented vascular malformation. Because of spontaneous fluctuation of the associated edema, the role of anti-VEGF remains questionable, while a functional response to therapy might be limited according to the progressive atrophic lamellar defect with intraretinal tissue loss.

Comparison of Surgically Excised Premacular Membranes in Eyes with Macular Pucker and Proliferative Vitreoretinopathy.

PURPOSE: To describe and compare characteristics of premacular membranes in idiopathic macular pucker (iMP) and proliferative vitreoretinopathy (PVR) using immunofluorescence and transmission electron microscopy. MATERIALS AND METHODS: For immunocytochemical and ultrastructural analyses, premacular membranes were harvested during vitrectomy from 16 eyes with iMP and 12 eyes with PVR. All specimens were processed as flat mounts for phase-contrast and fluorescence microscopy. We used 19 different primary antibodies such as anti-α-smooth muscle actin (α-SMA), anti-integrin-αv, anti-galectin, anti-IBA-1, anti-EMMPRIN (CD147), anti-ricinus (RCS) and anti-collagen-type I. Eight of 28 eyes were also prepared for transmission electron microscopy. RESULTS: In all eyes with iMP and PVR, positive immunoreactivity of integrins, especially αvß3 was found. There was also a strong staining of anti-α-SMA, anti-galectin, anti-EMMPRIN, anti-RCS, anti-IBA1 and anti-collagen-type I. Transmission electron microscopy showed that premacular membrane of iMP composed of myofibroblasts, glial cells and fibroblasts. In eyes with PVR, retinal pigment epithelial cells and myofibroblasts were seen as predominant cell types. CONCLUSION: Premacular membranes of iMP and PVR presented with similarities in cell distribution and immunoreactivity, but showed differences in cell composition. Herein, we demonstrate immunocytochemical characteristics involved in fibrotic processes. Cell transdifferentiation into myofibroblasts represents an important process in pathogenesis of both entities. In order to address future anti-fibrotic treatment strategies, we emphasize that both fibrotic diseases share distinct immunocytochemical and ultrastructural features.

Vitrectomy for Diabetic Macular Edema: Optical Coherence Tomography Criteria and Pathology of the Vitreomacular Interface.

PURPOSE: To correlate spectral-domain optical coherence tomography (SDOCT) criteria and clinical data with pathology of the vitreomacular interface (VMI) in eyes with diabetic macular edema (DME). DESIGN: Retrospective cross-sectional study and laboratory investigation. METHODS: We included specimens of 27 eyes of 26 patients with center-involved DME that underwent vitrectomy with peeling of the internal limiting membrane (ILM). Selection of specimens was consecutive and in retrospect using our register of the Vitreoretinal Pathology Unit. Clinical data and SDOCT examinations were correlated to immunocytochemistry and transmission electron microscopy. Classification of DME comprised sponge-like diffuse retinal thickening, cystoid macular edema, and serous retinal detachment. VMI was evaluated for presence of epiretinal membrane (ERM) and thickened vitreous cortex (tVC). RESULTS: ERMs and tVC were found in all DME types. Diffuse DME showed tVC more often than cystoid DME. Hyalocytes, contractile myofibroblasts, glial cells, matrix metalloproteinases-2 and -9, and collagen type I, II, and III were positive tested irrespective of DME type. There were no significant cell fragments at the retinal side of the ILM. Visual acuity improved in the majority of cases and macular thickness decreased significantly during mean follow-up of 17 ± 10 months. CONCLUSIONS: All eyes presented pathologic VMI changes irrespective of the OCT classification of DME type or presence of ERM. Composition of fibrocellular membranes at the VMI indicated remodeling of vitreous cortex and transdifferentiation of hyalocytes into myofibroblasts. Our findings might argue for an early surgical intervention in eyes with DME irrespective of the presence of traction formation imaged by SDOCT.

The Relationship Between Blue-Fundus Autofluorescence and Optical Coherence Tomography in Eyes With Lamellar Macular Holes.

Purpose: The purpose of this study was to evaluate the relationship between blue-fundus autofluorescence (B-FAF) and optical coherence tomography (OCT) in eyes with lamellar macular holes (LMHs). Methods: this was a multicenter, observational case series. Ninety-two eyes with LMH associated with the standard epiretinal membrane (ERM) or lamellar hole-associated epiretinal proliferation (LHEP) were evaluated. The eyes must also present an area of increased autofluorescence on B-FAF. Results: The ERM-alone group and the LHEP group differed with respect to the following variables: logarithm of the minimum angle of resolution best-corrected visual acuity (0.13 ± 0.13 vs. 0.25 ± 0.17; P < 0.001), central foveal thickness (218.74 ± 52.4 µm vs. 187.28 ± 50.29 µm; P = 0.008), FAF diameter (400.78 ± 189.36 µm vs. 503.37 ± 214.25 µm; P = 0.014), outer plexiform layer (OPL) diameter (382.10 ± 157.34 µm vs. 550.79 ± 228.05 µm; P = 0.0001), and disruption of external limiting membrane and ellipsoid zone, which was noted in only 1 and 3 eyes with ERM alone, respectively, and in 18 and 23 eyes with LHEP, respectively (P < 0.0001 for both observations). No difference was found for diameters measured at the level of the inner limiting membrane and schisis/cavitation. In both the ERM-alone group and the LHEP group, a strong correlation was found between the diameters measured on B-FAF and diameters measured at the OPL level on OCT images (P < 0.0001 for both groups). Conclusions: In eyes with LMHs, a strong correlation exists between the diameters of the holes measured with B-FAF and those measured at the OPL level with OCT. This may indicate that the loss or displacement of retinal cells containing macular pigment at the OPL level, specifically photoreceptors and/or Müller cells, is involved in this vitreomaculopathy.

Premacular membranes in tissue culture.

PURPOSE: To investigate integrity and characteristics of human premacular membranes (PMM) with and without standard tissue culturing using mechanical traction. METHODS: Premacular membranes were harvested from 32 eyes of 32 patients with idiopathic macular pucker during standard vitrectomy. By flat-mount preparation with phase contrast and interference microscopy, specimens were prepared for time-lapse microscopy, immunocytochemistry, and transmission electron microscopy. Sixteen of 32 specimens were held in tissue culture with tangential traction by using entomological pins. Of these, specimens of 7 eyes were analyzed with and without tissue culturing for comparison. Primary antibodies were used for myofibroblasts, hyalocytes, macro-/microglial cells, and retinal pigment epithelial and immune cells. RESULTS: Hyalocytes, macroglia, and microglia composed the main cell composition of surgically removed PMM. Correlation of time-lapse microscopy with immunofluorescence microscopy identified fast and unidirectional moving small round cells as microglia. Slowly moving elongated large cells were characterized as alpha-smooth muscle actin (α-SMA)-positive myofibroblasts. Following tissue culturing with tangential stretch, enhanced positive immunolabelling for α-SMA and integrins-αv was seen. All other labelling results were demonstrated to be similar with pre-culture conditions. Ultrastructural analysis revealed fibroblasts, myofibroblasts, and proliferation of glial cells following tissue culture. CONCLUSION: This study demonstrates abundance of fibroblasts, myofibroblasts, and glial cells in PMM from idiopathic macular pucker following tissue culture with tangential stretch application. We found enhanced contractive properties of the cultured PPM that appear to indicate transdifferentiation of the cell composition. This in vitro model may improve understanding of pathogenesis in traction maculopathies and help to establish further anti-fibrosis treatment strategies.