Ultrastructure of the Vitreomacular Interface in Full-Thickness Idiopathic Macular Holes: A Consecutive Analysis of 100 Cases

James

2008

Eye

133

Purpose/Background Epiretinal membrane (ERM) formation is a common change resulting in disturbance of macular vision and predisposing to rhegmatogenous retinal detachment. Current treatment strategies rely chiefly on surgical removal of the membranes from the surface of the retina, allowing the retina to remodel and reattach. Improved knowledge of the pathological process behind the formation of these membranes, particularly knowledge of the cell types involved in their formation, is likely to increase our understanding of the way this group of diseases behave and to improve treatment. Methods We reviewed the histological findings of 109 surgically removed specimens and correlated these to age-related changes seen in a 32 cadaver eyes studied after corneal harvesting. The samples were studied using light microscopy and immunocytochemistry. Results In all cases of idiopathic ERMs, including cellophane maculopathy, macular hole, and vitreomacular traction syndrome, laminocytes were the exclusive cell type present. In cases of macular pucker associated with retinal tears, the membranes contain variable cohesive groups of retinal pigment epithelial (RPE) cells in addition to laminocytes. In cases of proliferative diabetic retinopathy, membranes consist almost entirely of capillaries and hyaline stromal tissue, with or without haemosiderin pigment and RPE cells and in which laminocytes and ILM were not identified. In cadaver eyes PVD was seen in 17/32 (53%) of cases, and the vitreous was attached in 14/32 (43.7%) and in one case no vitreous was present. Isolated laminocytes were present on the retinal surface in 12/18 cases with detached vitreous and in 1/14 cases with attached vitreous. In all cases laminocytes were scanty and confined to the optic nerve head, macular or subjacent macular retina. Immunohistochemistry findings indicate that laminocytes are positive for glial fibrillary acidic protein (GFAP), cytokeratin marker AE1/AE3, type II collagen, and type IV collagen. In some cases novel basement membrane formation was seen. There was a tendency for increased positivity of GFAP and AE1/AE3 with increased cellularity, and where novel basement membrane formation was present. Conclusion Laminocytes are the fundamental cell type in idiopathic ERMs. These cells are frequently found in small and dispersed numbers in eyes containing a PVD. The presence of retinal pigment cells invariable indicates proliferative retinopathy and is only seen in association with a retinal detachment or tear. Diabetic membranes are composed of neovascular stromal tissue, which is most likely to be a response to retinal hypoxia.

Section: Introductionmentioning

confidence: 99%

Pathological changes in the vitreoretinal junction 1: epiretinal membrane formation

James

2008

Eye

133

“…In addition, ultrastructural analysis of the vitreomacular interface strongly suggests that the epiretinal fibrocellular proliferation often seen in association with idiopathic macular hole is a secondary rather than primary phenomenon. 7 We propose that traction-induced foveal damage occurring before or coincident with either spontaneous or surgical vitreofoveal separation may destabilize the fovea, predisposing a minority of eyes to macular hole formation at a subsequent time. As in our patients, the foveal disruption may be subtle and therefore not initially cause significant vision loss or clinically apparent changes in foveal architecture.…”

Section: Discussionmentioning

confidence: 99%

Traction-induced foveal damage predisposes eyes with pre-existing posterior vitreous detachment to idiopathic macular hole formation

Besirli

Johnson

2012

Eye

Aim To propose a new mechanism for the development of idiopathic macular hole in the setting of pre-existing posterior vitreous detachment (PVD). Methods Patients were examined clinically with fundus contact lens biomicroscopy and high-definition optical coherence tomography (OCT) was used to characterize the structural changes in the fovea following PVD. Results Two patients presented with vitreofoveal separation and were found by high-definition OCT to have subtle foveal disruption and irregularity of the foveal contour with no evidence of a full thickness macular hole. Sequential examination of these patients demonstrated delayed formation of idiopathic macular hole. Conclusion Traction-induced inner foveal damage occurring before or coincident with spontaneous vitreofoveal separation destabilizes the fovea and predisposes some eyes to delayed macular hole formation.

“…Latest data obtained via electron microscopy suggests that vitreal debri, formed by separation of the vitreal cortex (vitreoschisis), can trigger pronounced fibrocellular proliferation [6,9,13] which results in formation of a membrane that is made up of collagen; retinal pigment epithelium (RPE) cells; glial cells; astrocytes; fibrocytes; and macrophages [9,14], and which can be found on the posterior vitreal cortex and retinal interface, and that can, but does not have to, during the evolution of ERM, bridge the fovea.…”

Section: Introductionmentioning

confidence: 99%

“…Proliferation and transdifferentiation of hyalocytes that are, after posterior vitreous detachment (PVD), found in the remains of cortical gel on the surface of the retina lead to formation of an ERM [3][4][5][6][7][8][9]. ERM that occurs in early PVD is usually localized on the surface of the retina, below the separated posterior vitreal cortex.…”

Section: Introductionmentioning

confidence: 99%

Correlation between Epiretinal Membrane Bridging, Visual Acuity and Central Macular Thickness

Paovic¹,

Paović²

2017

J Cytol Histol

Epiretinal membrane or macular pucker is avascular, fibrocellular membrane that develops on the inner surface of the retina that can result in various stages of macular dysfunction. Fine epiretinal membranes lead to minimal visual loss, whilst epiretinal membranes (that may or may not bridge the fovea) are, in their more severe stages, accompanied by macular edema and image distortion that is caused by pronounced tractional membranes and perifoveal capillary leakage. Macular edema and its' type, as well as epiretinal membrane bridging the fovea can precisely be defined and monitored via optical coherence tomography.This study included a total of 138 patients (188 eyes) with epiretinal membranes (95 on the right and 93 on the left eye). Macular edema was present in 144 eyes with, and 69 eyes without, epiretinal membranes. Data obtained for both eyes indicates that upon analysis number of patients in both examined groups (epiretinal membrane bridged and did not bridge the fovea) increases exponentially with increased visual acuity, and suggests that there is no considerable difference in distribution of visual acuity with regards to patients in both examined groups. This data also indicates that patients with the worst central macular thickness (>500 μ) are represented only in the group of patients where epiretinal membrane had bridged the fovea, but that in both examined groups there is a difference in prevalence of patients with central macular thickness of 400 to 499 μ (more common in the group that did, than in the group that did not, bridge the fovea). Hence, there exists a relationship between epiretinal membrane that bridges the fovea and central macular thickness.Aim of this study is to determine the extent in which epiretinal membrane bridging or not bridging the fovea influences visual acuity and to determine the relationship between them; central macular thickness; and visual acuity.