1/24. 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 = vessel (Clic here for more details about this article) |
2/24. indocyanine green angiographic findings in idiopathic choroidal neovascularisation.PURPOSE: The authors report the cases of two patients affected with idiopathic choroidal neovascularisation studied with combined fluorescein angiography and indocyanine green (ICG) angiography. In particular the presence of choroidal abnormalities at ICG angiography which could not be detected by fluorescein angiography was studied. methods: Both patients underwent a complete systemic and ocular assessment. fluorescein angiography and ICG angiography were performed in a routine fashion at the time of presentation in both cases and after 14 months in the second patient. RESULTS: Results of the systemic investigations were unremarkable. A distinct dark rim surrounding the choroidal neovascular net was evident until the late phases of ICG angiography despite the presence of subretinal blood. Dilated choroidal vessels were observed beneath the neovascular membrane in both cases. In the first patient a hyperfluorescent area beyond the primary lesion was detected in the affected eye and a distinct leaking subfoveal choroidal venous vessel was found in the fellow eye. The second patient never showed other angiographic alterations either in the affected or in the fellow eye. CONCLUSIONS: ICG angiography has proved to be useful, both to better define and follow up the true extent of the pigment halo (healing response) around the neovascular membrane when subretinal blood and dye leakage at fluorescein angiography prevent its full appreciation, and to rule out other causes of choroidal neovascularisation in young healthy adults associated with either choroidal inflammatory focal lesions or choroidal vascular dynamic or inflammatory alterations.- - - - - - - - - - ranking = 0.4keywords = vessel (Clic here for more details about this article) |
3/24. ICGA-guided laser photocoagulation of feeder vessels of choroidal neovascular membranes in age-related macular degeneration. indocyanine green angiography.PURPOSE: To report the ability of indocyanine green angiography (ICGA) with a confocal scanning laser ophthalmoscope (SLO) to identify feeder vessels of choroidal neovascular membranes (CNVM) secondary to age-related macular degeneration (ARMD) and to show the feasibility of inducing complete closure of the CNVM by photocoagulation targeted exclusively to the feeder vessels. methods: Five consecutive patients with exudative ARMD in whom ICGA with the confocal SLO showed extrafoveal feeder vessels supplying choroidal neovascular nets had laser photocoagulation done only to the feeder vessels. In two patients, two separate membranes were seen. RESULTS: Laser photocoagulation resulted in closure of the feeder vessels and the CNVM in four patients. Complete closure was achieved with one treatment in one patient and with two treatments in three patients. In one patient, two treatments failed to close the feeder vessel and the CNVM, but a third, more intense laser treatment resulted in temporary closure of the feeder vessel and CNVM, which recanalized 2 to 4 weeks later with development of a large rip in the retinal pigment epithelium. In one patient, two separate CNVMs grew from the edge of the laser scars, but they were not directly related to the original CNVM and its feeder vessel, and were treated successfully. The same eye later developed subfoveal occult CNVM with gradual deterioration of visual acuity. In the other four patients, visual acuity improved in two and was unchanged in two. CONCLUSIONS: indocyanine green angiography with the confocal SLO can identify choroidal feeder vessels supplying CNVM secondary to ARMD. Laser treatment to such extrafoveal feeder vessels, particularly in membranes that are large or subfoveal, may be effective in closing the feeder vessel and CNVM with preservation of the fovea and central vision. More than one treatment may be required, however, and failures and complications may be expected with this treatment modality.- - - - - - - - - - ranking = 3keywords = vessel (Clic here for more details about this article) |
4/24. Polypoidal choroidal vasculopathy pattern in age-related macular degeneration: a clinicopathologic correlation.PURPOSE: To report the histopathologic features of surgically removed submacular tissue from an elderly patient with a pattern of polypoidal choroidal vasculopathy on indocyanine green angiography. methods: Clinical examination including fluorescein and indocyanine green angiography and light microscopy of surgical specimen. RESULTS: A thick yellow proteinaceous subretinal fluid was seen in the right macula of an 81-year-old white man. fluorescein angiography indicated progressive leakage from undetermined source apart from a few focal hyperfluorescent points. indocyanine green angiography showed several polyps as well as dilated choroidal vessels in the macula and along the superior temporal arcade. A large plaque was visualized in the late phase. Microscopically, the specimen consisted of a thick fibrovascular membrane located on the choroidal side of the retinal pigment epithelium (RPE). The RPE layer was discontinuous whereas on its choroidal side an almost intact layer of diffuse drusen was observed. A group of dilated thin-walled vessels were found that appeared to be saccular on serial sections. Some of these were located almost immediately under the diffuse drusen. CONCLUSION: Histologic examination of submacular tissue removed from an eye with polypoidal choroidal vasculopathy showed several aneurysmal dilatations located directly under diffuse drusen within a sub-RPE, intra-Bruch's fibrovascular membrane.- - - - - - - - - - ranking = 0.4keywords = vessel (Clic here for more details about this article) |
5/24. Histological findings of surgically excised choroidal neovascular membranes after photodynamic therapy.AIM: To investigate effects of photodynamic therapy (PDT) on human choroidal neovascularisation (CNV). methods: Two patients with recurrences after PDT with verteporfin underwent surgical extraction of the CNV. Immediately after surgical excision the subfoveal neovascular membranes were divided for light microscopic and for electron microscopic processing. For light microscopy tissues were embedded in paraffin. Sections were stained with haematoxylin and eosin, and the periodic acid Schiff (PAS) reaction was performed to determine histological diagnosis and to ensure tissue quality. For electron microscopy the specimens were fixed in glutaraldehyde and embedded in epoxy resin. Semithin sections were stained with uranyl acetate and lead citrate and examined with a transmission electron microscope. RESULTS: light microscopy showed thick fibrovascular membranes in both cases. On the outer surface remnants of retinal pigment epithelial cells resting on thickened inner aspect of Bruch's membrane were found. On the retinal side some outer segments were found. The membrane showed areas with irregularly shaped vessels. Electron photomicrographs showed occluded vessels within the CNV containing thrombotic masses and/or ultrastructural damage of the neovascular endothelium. Most of the vessels presented regressive changes with vacuolisation and fragmentation of the neovascular endothelium accompanied by disintegration of the endothelial cell layer. Extravasation of red blood cells was observed. Occasionally, vessels with normal endothelium containing intact red blood cells were observed. Some vessels contained immature endothelial cells. At some locations the retinal pigment epithelium cells (RPE) were metaplastic showing highly vacuolised cytoplasm. CONCLUSIONS: These findings suggest that the evidence of fluorescein leakage from the CNV and enlargement of the neovascular complex following PDT could be related to new vessel growth and recanalisation of occluded vessels. Additionally, RPE disturbances were observed in the specimens. This finding may be related to the original pathology or could indicate that PDT treatment may result in RPE atrophy.- - - - - - - - - - ranking = 1.4keywords = vessel (Clic here for more details about this article) |
6/24. radiotherapy of exudative age-related macular degeneration; a clinical and pathologic study.BACKGROUND: radiotherapy has recently been employed to treat patients with exudative macular degeneration in order to prevent severe visual loss. radiotherapy affects the evolution of exudative macular degeneration directly by endothelial toxicity, leading to capillary closure, and/or indirectly through its attenuating effects on the inflammatory response, mediated by macrophages and other inflammatory cells. methods: In this study we describe the histopathologic findings in a patient with exudative age-related macular degeneration (AMD) in both eyes whose right eye was treated with radiotherapy (5 times 2 Gy) 3 years before he died. The eyes were enucleated post mortem and investigated by light microscopy. Additionally, immunohistochemical investigation with antibodies against CD34 and CD68 was performed to identify patent endothelial cells and macrophages. RESULTS: Both eyes showed neovascular AMD consisting of mixed fibrocellular and fibrovascular membranes. capillaries in both the choriocapillaris and the neovascular membrane were patent in both eyes. macrophages were present in the choroidal neovascularization of both eyes. Neither preexistent choroidal, intraretinal, nor neovascular vessels showed increased wall thickness as sign of radiation damage. CONCLUSION: No radiation-related histopathologic effect could be demonstrated 3 years after radiation therapy in this patient with AMD.- - - - - - - - - - ranking = 0.2keywords = vessel (Clic here for more details about this article) |
7/24. Clinicopathologic studies of age-related macular degeneration with classic subfoveal choroidal neovascularization treated with photodynamic therapy.BACKGROUND: Photodynamic therapy (PDT) is a relatively new modality that is currently under clinical and experimental evaluation for treatment of subfoveal choroidal neovascularization (CNV). The authors report the case of an 82-year-old woman who underwent verteporfin-mediated PDT for classic subfoveal CNV. fluorescein angiography performed 2 weeks after treatment disclosed reduction of the initial area of neovascularization and leakage by approximately 60%. Three weeks after PDT, however, the area of leakage was almost the same size as that before treatment. The patient underwent submacular membranectomy almost 4 weeks after treatment. The authors describe the ultrastructural vascular changes after PDT and a clinicopathologic study of classic CNV. methods: The submacular membrane was studied by light and electron microscopy and immunohistochemical techniques. RESULTS: Ultrastructural examination of the peripheral vessels showed evidence of endothelial cell degeneration with platelet aggregation and thrombus formation. Occasional occluded vessels were surrounded by macrophages, a phenomenon previously reported to describe the process of resorption of such blood vessels. The vessels in the center of the membrane were unremarkable. CONCLUSION: Photodynamic therapy causes endothelial cell damage, thrombus formation, and vascular occlusion of classic CNV in age-related macular degeneration.- - - - - - - - - - ranking = 0.8keywords = vessel (Clic here for more details about this article) |
8/24. Quantifying changes in RPE and choroidal vasculature in eyes with age-related macular degeneration.PURPOSE: An image-analysis technique was developed to quantify changes in the retinal pigment epithelium (RPE) and choriocapillaris in eyes of deceased donors with age-related macular degeneration (AMD). methods: Both eyes of two donors with AMD and of one normal control donor were used to develop this technique. After removal of the anterior segments, the eyecups were hemisected through the macula, with the disc included in one half of the eyecup. The choroid with RPE cells was dissected from the sclera and incubated for alkaline phosphatase (APase) activity, and the pigment was partially bleached with H2O2. The APase-incubated choroid was flat embedded and sectioned after image and morphometric analyses. Quantitative computer-assisted morphometric analyses of the two AMD-affected eyes (cases 1 and 2) were compared with analysis of the normal eye of a 70-year-old control subject (case 3). RESULTS: The right eye in case 1 had geographic atrophy (GA) and demonstrated a large area in the posterior pole with very few RPE cells (90% loss of RPE), but the border of the area of RPE atrophy was not well defined. The density of choroidal blood vessels in this area was reduced 30% to 50%, compared with the same regions in the control eye. No area was completely devoid of choriocapillaris. Clinically undetected choroidal neovascularization (CNV) was observed in the right eye in case 1 in both the periphery and the macula and was generally associated with surviving RPE cells. The right eye in case 2 had GA (areolar RPE atrophy) and demonstrated a reduction in vascular density in the area from disc to macula that was even greater than that in the eye in case 1 (53% reduction in the submacular region). RPE atrophy between the disc and macula was almost complete. The border of the RPE defect was clearly delineated and coincided closely with the area of decreased choroidal vascular density. Surviving choriocapillaris in the area of RPE atrophy was significantly narrower than choriocapillaris in the control subject and in normal areas of the eyes with GA (P < 0.0001). CONCLUSIONS: In these eyes with GA, RPE atrophy was more severe than loss of choriocapillaris. Surviving choriocapillaris in areas with complete RPE loss was highly constricted. The association of surviving RPE cells with CNV suggests that RPE cells may furnish a stimulus for new vessel formation or stabilization.- - - - - - - - - - ranking = 0.4keywords = vessel (Clic here for more details about this article) |
9/24. Successful photodynamic therapy combined with laser photocoagulation in three eyes with classic subfoveal choroidal neovascularisation affecting two patients with multifocal choroiditis: case reports.Multifocal choroiditis (MC) is an idiopathic choroidal inflammatory disease affecting young subjects. Secondary choroidal--and often central--neovascularisation is a frequent complication leading to a poor visual prognosis. Photodynamic therapy (PDT) has now proven to be successful to treat classic subfoveal choroidal neovascularisation in age-related macular degeneration and in pathologic myopia. We describe the treatment applied to classic choroidal neovascularisation in two young women with MC, two eyes with subfoveal neovascular membrane and one eye in which new vessels encroach the foveal avascular zone. PDT has been useful in the three reported eyes, with stable or improved visual acuity. In two of them, it even made the membrane retract and become extrafoveal, allowing a secondary treatment using conventional laser.- - - - - - - - - - ranking = 0.2keywords = vessel (Clic here for more details about this article) |
10/24. Clinicopathological correlation of polypoidal choroidal vasculopathy revealed by ultrastructural study.AIMS: To describe the clinical and histopathological findings in a patient with polypoidal choroidal vasculopathy. methods: A 76 year old Japanese man had a discrete, orange-red lesion of 1 disc diameter in the macula, with the fluorescein and indocyanine green angiographic and optical coherence tomographic findings compatible with polypoidal choroidal vasculopathy. He underwent a surgical removal of the macular lesion, followed by light and electron microscopic examinations. RESULTS: The histopathological examination revealed that the specimen consisted of degenerated retinal pigment epithelium-Bruch's membrane-choriocapillaris complex and inner choroid. A tortuous, unusually dilated venule was present adjacent to an arteriole with marked sclerotic changes, appearing to form arteriovenous crossing. These vessels seemed to represent native inner choroidal vessels, and had haemorrhage per diapedesis. blood cells and fibrin filled the lumina of the vessels and accumulated in the extravascular spaces, indicating vascular stasis. CONCLUSION: Hyperpermeability and haemorrhage due to stasis of a dilated venule and an arteriole involved by sclerosis at the site where they cross in the inner choroid might cause oedema and degeneration of the tissue. Voluminous accumulation of blood cells and fibrin might generate elevation of tissue pressure sufficient to displace the weakened lesion anteriorly. The result suggests that the polypoidal vessels in this case represent abnormality in the inner choroidal vasculature.- - - - - - - - - - ranking = 0.8keywords = vessel (Clic here for more details about this article) |
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