Natural History and Surgical Outcomes of Lamellar Macular Holes.

PURPOSE: To assess the natural history and surgical outcomes of lamellar macular holes (LMHs). DESIGN: Retrospective and consecutive case series. SUBJECTS: Patients with LMHs from multiple tertiary care centers. METHODS: Clinical charts and OCT scans were reviewed. MAIN OUTCOME MEASURES: The visual acuity (VA) changes and the occurrence rate of full-thickness macular hole (FTMH) were studied in both groups. Within the operated group, factors associated with 6-month VA and development of FTMH were explored. RESULTS: One hundred seventy-eight eyes were included, of which 89 were monitored and 89 underwent surgery. In the observation group, the mean VA decreased from 0.25 ± 0.18 to 0.28 ± 0.18 logarithm of the minimum angle of resolution (logMAR; P = 0.13), with 14 eyes (15.7%) that lost ≥ 0.2 logMAR VA, after 45.7 ± 33.3 months. Nine eyes (10.1%) spontaneously developed an FTMH. In the operated group, the mean VA increased from 0.47 ± 0.23 to 0.35 ± 0.25 logMAR at 6 months (P < 0.001) and 0.36 ± 0.28 logMAR (P = 0.001) after 24.1 ± 30.1 months. By multivariate analysis, better baseline VA (P < 0.001), the presence of an epiretinal membrane (P = 0.03), and the peeling of the internal limiting membrane (ILM; P = 0.02), with a greater effect of ILM perihole sparing, were associated with a greater 6-month VA. Perihole epiretinal proliferation sparing was associated with a better postoperative VA by univariate analysis (P = 0.03), but this was not significant by multivariate analysis. Eight eyes (9.0%) developed a postoperative FTMH. Using Cox proportional hazard ratios [HRs], pseudophakia at baseline (HR, 0.06; 95% confidence interval [CI], 0.00-0.75; P = 0.03) and peeling of the ILM (HR, 0.05; 95% CI, 0.01-0.39; P = 0.004) were protective factors, while ellipsoid zone disruption (HR, 10.5; 95% CI, 1.04-105; P = 0.05) was associated with an increased risk of FTMH. CONCLUSION: Observed eyes with LMH experienced, on average, progressive VA loss. Patients with LMH and altered vision may benefit from surgery. Internal limiting membrane peeling, with perihole ILM sparing, represents a crucial step of the surgery associated with a greater VA and a lower risk of postoperative FTMH. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

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.

Hyalocytes in proliferative vitreo-retinal diseases.

Introduction: Hyalocytes are sentinel macrophages residing within the posterior vitreous cortex anterior to the retinal inner limiting membrane (ILM). Following anomalous PVD and vitreoschisis, hyalocytes contribute to paucicellular (vitreo-macular traction syndrome, macular holes) and hypercellular (macular pucker, proliferative vitreo-retinopathy, proliferative diabetic vitreo-retinopathy) diseases. Areas covered: Studies of human tissues employing dark-field, phase, and electron microscopy; immunohistochemistry; and in vivo imaging of human hyalocytes. Expert opinion: Hyalocytes are important in early pathophysiology, stimulating cell migration and proliferation, as well as subsequent membrane contraction and vitreo-retinal traction. Targeting hyalocytes early could mitigate advanced disease. Ultimately, eliminating the role of vitreous and hyalocytes may prevent proliferative vitreo-retinal diseases entirely.

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.

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.

[Retinal imaging of vitreomacular traction diseases]. / Retinale Bildgebung bei traktiven vitreomakulären Erkrankungen.

Advances in imaging techniques of the retina have substantially enhanced our current understanding of the pathogenesis, morphology and prognosis of vitreomacular retinal diseases. Optical coherence tomography-based criteria and classification systems were recently proposed for uniform diagnoses and treatment recommendations for patients with vitreomacular traction, epiretinal gliosis and the various forms of macular holes. This article provides an overview of the different retinal imaging modalities as well as the currently recommended classification for vitreomacular traction pathologies.

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.

Impact of Sub-Retinal Fluid on the Long-Term Incidence of Macular Atrophy in Neovascular Age-related Macular Degeneration under Treat & Extend Anti-Vascular Endothelial Growth Factor Inhibitors.

Sub-retinal fluid (SRF) has been discussed as a protective factor against macular atrophy in eyes with neovascular age-related macular degeneration (nAMD).To gauge the impact of SRF on macular atrophy, a database of 310 nAMD eyes was screened for eyes manifesting an SRF-only phenotype under treat & extend anti-VEGF treatment, defined as nAMD expressing CNV exudation beyond the three monthly anti-VEGF loading doses by SRF only without any signs of exudative intra-retinal fluid (IRF) for ≥3 years. Incidence of macular atrophy and treatment responses were evaluated on multimodal imaging, including optical coherence tomography (OCT), blue autofluorescence (BAF) and near-infrared (NIR) confocal scanning laser ophthalmoscopy and fluorescence and indocyanine green angiography (FAG/ICGA). In total, 27 eyes (8.7%) of 26 patients with a mean follow-up of 4.2 ± 0.9 (3-5) years met the inclusion criteria. Mean age was 72 ± 6 (range: 61-86) years. The SRF only phenotype was seen from baseline in 14 eyes (52%), and in 13 eyes (48%) after a mean 1.0 ± 1.3 (1-3) injections. In years 1 to 5, mean 7.5, 5.9, 6.1, 6.1 and 7.0 anti-VEGF injections were given (p = 0.33). Cumulative macular atrophy incidence was 11.5% at year 1, 15.4% throughout years 2 to 4, and 22.4% at year 5. In conclusion, eyes manifesting activity by SRF only in treat & extend anti-VEGF regimen for nAMD seem to exhibit rather low rates of macular atrophy during long-term follow-up. SRF might be an indicator of a more benign form of nAMD.

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.

Foveal Abnormality associated with epiretinal Tissue of medium reflectivity and Increased blue-light fundus Autofluorescence Signal (FATIAS).

PURPOSE: To describe a distinct vitreomacular interface disorder (VMID) termed Foveal Abnormality associated with epiretinal Tissue of medium reflectivity and Increased blue-light fundus Autofluorescence Signal (FATIAS). METHODS: A case series including forty-seven eyes of 47 patients. The included eyes must present an irregular foveal contour on optical coherence tomography (OCT) and a pathologically increased autofluorescent signal at the fovea on blue-light fundus autofluorescence (B-FAF). Main outcome measures were morphologic characteristics of the lesions, logarithm of minimum angle of resolution (logMAR) best-corrected visual acuity (BCVA), and central foveal thickness (CFT). RESULTS: The following two types of FATIAS were identified: (1) the step type characterized by an asymmetric contour of the foveal pit and by a tissue of medium reflectivity on the foveal surface and (2) the rail type characterized by a shallow foveal pit and a rail of tissue of medium reflectivity on the foveal surface. The outer retinal bands were continuous in all cases. Both types presented with an area of increased B-FAF signal, usually bilobed in the step type and round and centered on the foveal pit in the rail type. LogMAR BCVA was 0.09 ± 0.1 and 0.1 ± 0.1 (P = 0.91), and CFT was 197.8 ± 9.7 and 202.2 ± 13.2 (P = 0.19) in the step and in the rail group, respectively. CONCLUSIONS: We describe a distinct VMID named FATIAS. Two types of FATIAS may be appreciated with SD-OCT and B-FAF analyses, the step and the rail type. Both are characterized by abnormal foveal contour and autofluorescence signal.

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.

DEVELOPMENT AND PROGRESSION OF A LAMELLAR MACULAR HOLE WITH LAMELLAR HOLE-ASSOCIATED EPIRETINAL PROLIFERATION.

PURPOSE: To describe evolution and progression of a lamellar macular hole (LMH) with "lamellar hole-associated epiretinal proliferation (LHEP)" using spectral-domain optical coherence tomography and fundus autofluorescence. METHODS: Observational case report. RESULTS: We report on a 63-year-old male patient demonstrating a complete history of LMH development with LHEP occurring during a follow-up period of 8 years. Presenting with a normal foveal contour and attached posterior vitreous at first visit, an LMH developed shortly after incomplete posterior vitreous detachment with vitreopapillary adhesion. On spectral-domain optical coherence tomography images, progression of the LMH including enlargement of the intraretinal cavitation and decrease in the retinal thickness were documented. An increase of LHEP was first documented 6 months after LMH evolution. One month after cataract surgery and 6 years after the first visit, a full-thickness macular hole developed that closed spontaneously after 4 weeks. Localization of LHEP had moved into the foveal defect toward the outer retinal layers. Thereafter, the LMH was stable, and the patient presented with a visual acuity of 20/25. CONCLUSION: Proper follow-up time is important for studying eyes with an LMH. Epimacular cell proliferation shows progression over time that appears to be associated with morphologic changes of the LMH including shape of the lamellar defect, amount of LHEP, and contractive properties of epiretinal tissue. The presence of LHEP was documented shortly after posterior vitreous detachment.

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.

In Vitro Comparison of 2D-Cell Culture and 3D-Cell Sheets of Scleraxis-Programmed Bone Marrow Derived Mesenchymal Stem Cells to Primary Tendon Stem/Progenitor Cells for Tendon Repair.

The poor and slow healing capacity of tendons requires novel strategies to speed up the tendon repair process. Hence, new and promising developments in tendon tissue engineering have become increasingly relevant. Previously, we have established a tendon progenitor cell line via ectopic expression of the tendon-related basic helix-loop-helix (bHLH) transcription factor Scleraxis (Scx) in human bone marrow mesenchymal stem cells (hMSC-Scx). The aim of this study was to directly compare the characteristics of hMSC-Scx cells to that of primary human tendon stem/progenitors cells (hTSPCs) via assessment of self-renewal and multipotency, gene marker expression profiling, in vitro wound healing assay and three-dimensional cell sheet formation. As expected, hTSPCs were more naive than hMSC-Scx cells because of higher clonogenicity, trilineage differentiation potential, and expression of stem cell markers, as well as higher mRNA levels of several gene factors associated with early tendon development. Interestingly, with regards to wound healing, both cell types demonstrate a comparable speed of scratch closure, as well as migratory velocity and distance in various migration experiments. In the three-dimensional cell sheet model, hMSC-Scx cells and hTSPCs form compact tendinous sheets as histological staining, and transmission electron microscopy shows spindle-shaped cells and collagen type I fibrils with similar average diameter size and distribution. Taken together, hTSPCs exceed hMSC-Scx cells in several characteristics, namely clonogenicity, multipotentiality, gene expression profile and rates of tendon-like sheet formation, whilst in three-dimensional cell sheets, both cell types have comparable in vitro healing potential and collagenous composition of their three-dimensional cell sheets, making both cell types a suitable cell source for tendon tissue engineering and healing.