1/49. Peripheral choriovitreal neovascularization in proliferative diabetic retinopathy: histopathologic and ultrastructural study.We describe the histopathologic and ultrastructural evidence of choriovitreal neovascularization in the peripheral fundus of a non-vitrectomized eye with proliferative diabetic retinopathy (PDR). One eye with PDR was surgically enucleated because of neovascular glaucoma and studied with light and electron microscopy. The eye had neovascular membranes at the ora serrata of the peripheral fundus. The newly formed vessels originated from the choroid, passed through Bruch's membrane and the retina, and extended into the vitreous. These vessels had either developing or mature characteristics. The endothelial cells of the developing vessels contained a bulky cytoplasm with many intracytoplasmic filaments, ribosomes and rough endoplasmic reticulum. Budding endothelial cells were frequently found in the developing vessels. The endothelial cells of the mature vessels had attenuated cytoplasm and fenestrations with diaphragms. These observations suggest that choriovitreal neovascularization in the peripheral fundus is one of the features of PDR.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
2/49. vitrectomy for cystoid macular oedema with attached posterior hyaloid membrane in patients with diabetes.AIM: To report the success of vitrectomy in eliminating cystoid macular oedema and improving vision in three eyes of two patients with diabetic cystoid macular oedema. In all of the eyes there was no ophthalmoscopic evidence of traction from a posterior hyaloid membrane or from proliferative tissue. methods: Pars plana vitrectomy was performed on three eyes of two patients with diabetic cystoid macular oedema who did not show traction upon examination with a slit lamp biomicroscope and a scanning laser ophthalmoscope. RESULTS: Cystoid changes disappeared 1, 3, and 5 days, postoperatively, and diffuse macular oedema resolved within 2 weeks. The visual acuity was improved and maintained. CONCLUSION: vitrectomy can be effective in some patients with diabetic cystoid macular oedema even in patients who lack evidence of traction by ophthalmoscopy.- - - - - - - - - - ranking = 2.5keywords = membrane (Clic here for more details about this article) |
3/49. Electron immunocytochemical analysis of posterior hyaloid associated with diabetic macular edema.BACKGROUND: Tangential traction in the macula from a thickened posterior hyaloid of the vitreous has been implicated as a cause of diffuse diabetic macular edema. vitrectomy with peeling of the posterior hyaloid has been shown to reduce retinovascular leakage and improve vision in select patients. We report a clinicopathologic correlation using electron microscopy and electron immunocytochemistry to characterize the membrane infiltrating the posterior hyaloid in two such patients. methods: Two patients presented with vision loss associated with diffuse diabetic macular edema and an attached, thickened, and taut posterior hyaloid. The patients underwent vitrectomy with peeling of the posterior hyaloid. The premacular posterior hyaloid specimens then were analyzed by electron microscopy with immunocytochemical staining for cytokeratin and glial fibrillary acidic protein. RESULTS: Both posterior hyaloid specimens contained collagen and a large cellular component. Immunogold labeling showed cells positive for glial fibrillary acidic protein or cytokeratin. With double labeling, no cells expressed both proteins simultaneously. Clinically, both patients had vision improvement and macular edema resolution after surgery. CONCLUSIONS: The thickened, taut posterior hyaloid observed in our patients with diabetic macular edema contained cells of glial and epithelial origin. This cellular infiltration may contribute to abnormal vitreomacular adherence and could play a role in the pathogenesis of macular edema in some patients with diabetes.- - - - - - - - - - ranking = 0.5keywords = membrane (Clic here for more details about this article) |
4/49. Surgical treatment for severe diabetic macular edema with massive hard exudates.PURPOSE: Massive diabetic macular exudates respond poorly to conventional laser treatment. The purpose of this study was to analyze the surgical results of eyes with massive hard exudates secondary to diabetic macular edema treated with combined pars plana vitrectomy, posterior hyaloid removal, focal endolaser treatment, and panretinal photocoagulation. methods: The author retrospectively analyzed the surgical outcome of 13 consecutive eyes (11 patients) with massive diabetic macular exudates. All patients had had at least one session of focal and/or grid laser treatment without any effect. Pars plana vitrectomy, posterior hyaloid removal, focal macular endolaser treatment, and intraoperative panretinal photocoagulation were performed. Postoperative visual acuity, evolution of macular edema, and hard exudates were recorded. RESULTS: All 13 eyes showed significant decreases in macular edema and hard exudates, a process that became clinically obvious 3 months after the operation. Eleven eyes had improved vision of at least two lines during an average follow-up period of 14.8 months. Intraoperative and postoperative complications included angle closure glaucoma (one eye), persistent vitreous hemorrhage (two eyes), choroidal detachment (one eye), intravitreal fibrin formation (one eye), epiretinal membrane formation (one eye), and neovascular glaucoma (one eye). CONCLUSION: Combined surgery may offer an opportunity for improvement of vision and reduction of massive macular exudates in patients with severe diabetic macular edema.- - - - - - - - - - ranking = 0.5keywords = membrane (Clic here for more details about this article) |
5/49. Surgical removal of choroidal neovascular membranes after laser photocoagulation for diabetic maculopathy.PURPOSE: Choroidal neovascularisation (CNV) occurs rarely following laser photocoagulation for macular oedema in diabetic retinopathy, and its management is not well established. We report the clinical course and visual outcomes in a series of patients who underwent surgical extraction of the CNV membrane. methods: A retrospective review of 4 cases was carried out. RESULTS: Two women and 2 men, mean age 59.5 (range 58-62) years, were reviewed. The CNV developed 2-24 (mean 11) months after laser coagulation and resulted in decreased visual acuity to between 6/60 and HM. All underwent pars plana vitrectomy, extraction of the CNV membrane and fluid-air exchange. Follow-up ranged between 9 and 48 months. In 2 patients, the vision improved by 4 and 1 Snellen lines respectively and remained stable, in 1 patient it improved by 1 line initially but then regressed to CF, and in 1 patient it remained unchanged. recurrence of CNV occurred in only 1 patient. Histological characteristics were those of CNV without evidence of photoreceptors. CONCLUSIONS: This study shows that surgical removal of post-laser CNV is technically feasible despite the previous laser scars and may have beneficial outcome. This surgical approach may provide a therapeutic option in such patients.- - - - - - - - - - ranking = 3keywords = membrane (Clic here for more details about this article) |
6/49. vitrectomy for diabetic macular edema: the role of posterior vitreous detachment and epimacular membrane.PURPOSE: To evaluate the surgical efficacy of pars plana vitrectomy on eyes with diabetic macular edema in the presence or absence of a complete posterior vitreous detachment and with or without an epimacular membrane. methods: Pars plana vitrectomy was performed on 30 eyes of 29 cases with diabetic macular edema. visual acuity was measured, and retinal thickness was determined by optical coherence tomography before and after vitrectomy. To evaluate the relationship between the effects of vitrectomy and the presence or absence of posterior vitreous detachment and/or epimacular membrane, all eyes were placed into one of four groups: group A, eyes with posterior vitreous detachment and epimacular membrane; B, eyes with posterior vitreous detachment and without epimacular membrane; C, eyes without posterior vitreous detachment and with epimacular membrane; and D, eyes without posterior vitreous detachment and without epimacular membrane. The expression of vascular endothelial growth factor and interleukin-6 was investigated immunohistochemically in epimacular membrane specimens obtained from seven eyes with diffuse diabetic macular edema. RESULTS: The postoperative mean visual acuity (0.653 /- 0.350: mean /- SD logarithm of minimal angle of resolution [logMAR]) was significantly better than the mean preoperative visual acuity (0.891 /- 0.319 logMAR; Wilcoxon signed-rank test, P =.0007). The postoperative foveal thickness (264.5 /- 118.6 microm) was significantly thinner than the preoperative foveal thickness (477.8 /- 147.7 microm; Wilcoxon signed-rank test, P <.0001). There were no significant differences in the improvement of visual acuity and decrease of foveal thickness between the four groups (Kruskal-Wallis test, P =.13, P =.65, respectively). All of the epimacular membranes obtained at surgery expressed vascular endothelial growth factor and interleukin-6. CONCLUSIONS: These results demonstrated that vitrectomy with removal of epimacular membrane is generally an effective procedure in reducing diabetic macular edema, and the outcome does not depend on the presence absence of posterior vitreous detachment and epimacular membrane.- - - - - - - - - - ranking = 7keywords = membrane (Clic here for more details about this article) |
7/49. Increased platelet aggregation in diabetic patients with microangiopathy despite good glycemic control.The pathogenesis of diabetic micro- and macroangiopathy cannot be fully explained by hyperglycemia alone. To clarify diabetic complications mediated by increased platelet activity, we have studied platelet aggregation and its second messenger molecules such as protein kinase c (PKC), RhoA, and phosphatidylinositol 3-kinase (PI3- kinase), in six diabetic patients with diabetic retinopathy and other diabetic complications in spite of good glycemic control. Their HbA(1c) levels throughout the observation period had been less than 6% with diet treatment alone, despite which diabetic retinopathy developed to the pre-proliferative stage during 2-8 years observation. Low-dose thrombin (< 0.5 U/ml)-stimulated platelet aggregation in the diabetic patients was enormously elevated compared with healthy control subjects. PKC, RhoA and PI3-kinase activities in the cytosol- and membrane-associated fractions were examined in the platelets from the two patients (Cases 2 and 4). Platelet membrane-associated RhoA and PI3-kinase activity in Case 2 were increased before the stimulation. Platelet RhoA and PI 3-kinase activities in Case 4 were increased after the stimulation with low-dose thrombin (0.01 U/ml). Membrane-associated immunoreactive PKC alpha, but not PKC beta in Cases 2 and 4 was elevated. Although platelet hyperactivity in these four patients was observed, PKC and RhoA in mononuclear leukocytes from these patients were not different from healthy subjects. Membrane-associated PKC alpha and RhoA immunoreactivities also increased in the other three cases. These results suggest that hyperreactivity of PKC alpha may lead to increased RhoA and PI3-kinase activities and platelet hyperfunction in diabetic patients with good glycemic control, and that raised platelet PKC alpha may be implicated in the pathogenesis of diabetic complications.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
8/49. Photodynamic therapy for choroidal neovascularization after thermal laser photocoagulation for diabetic macular edema.PURPOSE: To report the use of photodynamic therapy for treating a choroidal neovascular membrane secondary to thermal laser photocoagulation. DESIGN: Interventional case report. methods: A 61-year-old man with a choroidal neovascular membrane secondary to thermal laser photocoagulation for diabetic macular edema was treated with photodynamic therapy. RESULTS: Subjective and objective improvement in visual acuity and improvement of fluorescein angiogram have been demonstrated for more than a year after treatment. CONCLUSIONS: Photodynamic therapy may be useful for treating patients with choroidal neovascularization secondary to thermal laser photocoagulation.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
9/49. Increased diode laser uptake in inner retinal layers after indocyanine green staining of the internal limiting membrane.Intraoperative use of indocyanine green to stain the internal limiting membrane assists in its visualization and removal. This article describes increased uptake of diode laser energy by the superficial layers of the retina after indocyanine green staining of the internal limiting membrane in a patient with diabetic macular edema and a taut, attached posterior hyaloid. The patient was undergoing pars plana vitrectomy, removal of the posterior hyaloid, and indocyanine green-assisted peeling of the internal limiting membrane. In addition, panretinal diode laser endophotocoagulation was performed after discovering retinal neovascularization. In areas that were more intensely stained with indocyanine green, the clinical appearance and optical coherence tomography scans demonstrated markedly increased laser energy uptake in the superficial layers of the retina. This case indicates near-infrared or infrared laser procedures performed in areas of indocyanine green-stained internal limiting membrane may necessitate adjustment of laser power and technique.- - - - - - - - - - ranking = 4keywords = membrane (Clic here for more details about this article) |
10/49. Use of perfluorocarbon liquid during vitrectomy for severe proliferative diabetic retinopathy.AIM: To evaluate the value of using perfluorocarbon liquid (PFCL) during vitrectomy in eyes with proliferative diabetic retinopathy (PDR). methods: The surgical records of eyes with PDR (291 eyes of 228 patients) that underwent vitrectomy in the vitreoretinal service of Osaka Medical College (April 1999 to October 2001) were reviewed. From these, 18 eyes of 15 patients had PFCL used during vitrectomy, and the preoperative and postoperative findings of these eyes were analysed. RESULTS: All of the 18 eyes had advanced PDR with tractional and/or rhegmatogenous retinal detachment. PFCL enabled easier flattening of the retinal folds and effective endophotocoagulation. In two cases, PFCL was used to flatten a bullous retinal detachment that developed when a tight vitreoretinal adhesion was loosened. In two other cases with combined traction/rhegmatogenous retinal detachment, PFCL was used to tamponade the detached retina which then allowed successful membrane dissection. Anatomical success was obtained in 16 of the 18 cases (mean follow up time 13.3 months) with visual acuity of 20/200 or better in nine eyes (50%). CONCLUSIONS: PFCL is considered to be a useful adjunct during vitrectomy for the treatment of severe PDR.- - - - - - - - - - ranking = 0.5keywords = membrane (Clic here for more details about this article) |
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