Photodynamic therapy (PDT) involves the induction of endothelial cell death or occlusion of blood vessels. On the basis of this mechanism of action, PDT is used in the treatment of predominant classic choroidal neovascularization (CNV), if the classic component is over 50%, and in myopic CNV. This study describes 2 cases of distinctive, abnormal, large, subretinal new vessels that are thought to have originated from the choroids. Diminishment of the new vessels was observed following treatment with PDT.
Retinal Vessels/drug effects/*pathology ; Retinal Diseases/*drug therapy/pathology ; *Photochemotherapy ; Neovascularization, Pathologic/*drug therapy/pathology ; Middle Aged ; Male ; Humans ; Female ; Angiography

We studied the ultrastructural features of four consecutive subfoveal neovascularmembranes (SFNM) associated with age-related macular degeneration. Cellular components of the membranes included retinal pigment epithelial (RPE) cells, endothelium-lined vascular channels, macrophages, myofibroblasts, fibrocytes, glial cells, erythrocytes, and lymphocytes. Extracellular interstitial constituents included collagen fibrils, basal laminar deposits, fibrin and young elastic fibrils. These findings show that SFNMs consist of various cells originating from surrounding tissues and vessels. Among these RPE cells and macrophages are the main cellular components and in conjunction with various extracellular matrix, especially collagen, may play an important role in the formation and maintenance of the membranes.
Basement Membrane/surgery/ultrastructure ; Humans ; Macular Degeneration/complications ; Microscopy, Electron ; Retina/*ultrastructure ; Retinal Neovascularization/etiology/*pathology/surgery

The visual results of laser photocoagulation for subfoveal choroidal neovascular membrane (CNVM) has not always been satisfactory. The surgical removal of the neovascular membrane may be another treatment option. To investigate the prognosis and risk factors of this surgery, we analyzed the results of surgical removal of subfoveal CNVM (23 eyes), subfoveal hemorrhage with CNVM (6 eyes), and subfoveal hemorrhage alone (6 eyes). The mean follow-up period was 17.7 months (range 2 to 47 months). The mean preoperative membrane size was 0.89 disc diameter and the mean postoperative retinal pigment epithelial (RPE) defect size was 1.33 disc diameter. Visual improvement was observed in 13 out of the 23 eyes (56.5%) with sufoveal CNVM, four out of the six eyes (66.6%) with subretinal hemorrhage and CNVM, and five out of the six eyes (83.3%) with subretinal hemorrhage only. The visual outcome of subfoveal CNVM surgery was related to the presence of a subfoveal RPE defect (p = 0.005) rather than to the size of the RPE defect. No recurrence of neovascular membrane was observed during the follow up period. In conclusion, surgical removal may be a good alternative treatment for subfoveal CNVM.
Choroidal Neovascularization/surgery* ; Choroidal Neovascularization/diagnosis ; Choroidal Neovascularization/complications ; Comparative Study ; Female ; Fluorescein Angiography ; Fovea Centralis/surgery ; Fovea Centralis/pathology ; Fundus Oculi ; Human ; Laser Coagulation* ; Male ; Middle Age ; Pigment Epithelium of Eye/pathology ; Prognosis ; Retinal Hemorrhage/surgery ; Retinal Hemorrhage/diagnosis ; Retinal Hemorrhage/complications ; Retrospective Studies ; Risk Factors ; Visual Acuity

OBJECTIVETo evaluate the role of different oxygen concentration (FiO2) and different period of oxygen exposure on oxygen-induced retinopathy (OIR) in neonatal mice and to provide evidences for proper clinical oxygen therapy.

METHODSTwo hundred and four 7-day-old (P7) C57BL/6J mice were exposed to different FiO2 30%, 50% and 75% for 5, 7 and 9 days. The mice were divided into eight groups: groups 1 - 3 (n = 24 in each) were exposed to 30% oxygen for 5, 7 and 9 days, respectively; groups 4 - 6 (n = 24 in each) were exposed to 50% oxygen for 5, 7 and 9 days, respectively; group 7 (n = 30) was exposed to 75% hyperoxia for 5 days; group 8 (n = 30) was exposed to room air. Proliferative neovascular responses were estimated by observing vascular patterns in adenosine diphosphate-ase (ADPase) stained retina flat-mounts and quantitated by counting the number of new vascular cell nuclei extending into the internal limiting membrane in cross-sections.

RESULTS(1) Vascular patterns in retina flat-mounts: a) When FiO2 was 30%, the entire vascular pattern was completely normal after 5 and 7 days exposure; although the deep vascular system seemed slightly constricted after 9 days exposure, it recovered 2 days later and matured at P21. b) When FiO2 was 50%, after 5 days exposure (group 4), the larger vessels constricted and central perfusion decreased moderately; after exposing to room air for 2 days, neovascularization was seen; however, the entire vascular pattern was almost normal at P17. After 7 days of exposure to 50% O2 (group 5), the vascular pattern recovered a bit, seemed to be better than that of group 4; after 9 days of exposure to 50% O2 (group 6), only slight constriction could be seen and it disappeared 2 days later and all vessels matured later. c) When FiO2 was 75%, after 5 days exposure to hyperoxia, the larger vessels became tortuous and constricted, central perfusion became decreased obviously; after exposing to room air for 2 days, neovascularization was seen; and this response was maximal at P17 - P21. However, the mortality of nurser mice and pups increased dramatically when the duration of hyperoxia was prolonged. (2) Quantitative results in cross-sections: neovascular nuclei extending into the vitreous reached (41.9 +/- 2.8) per section in 75% oxygen group, while less than 1 in every other groups, which was statistically different (P < 0.0001).

CONCLUSIONSFiO2 and the duration of hyperoxia could affect retinal vascular development. Low and moderate FiO2 could induce reversible vessel changes, while high FiO2 induced irreversible changes which should be avoided in clinic.

Animals ; Disease Models, Animal ; Humans ; Hyperoxia ; pathology ; Infant, Newborn ; Mice ; Mice, Inbred C57BL ; Oxygen ; adverse effects ; Oxygen Inhalation Therapy ; adverse effects ; Retinal Neovascularization ; pathology ; Retinal Vessels ; pathology ; Retinopathy of Prematurity ; pathology

OBJECTIVEFluctuations in arterial oxygen are associated with development of severe retinopathy of prematurity (ROP) in humans. However, the causal relationship between oxygen variability and ROP remains unknown. The authors developed a rat model of retinal neovascularization by repeated fluctuations of inhaled oxygen between hypoxia and hyperoxia to investigate the mechanism of the development of retinal neovascularization, the regulation of vascular endothelial growth factor (VEGF) and KDR/Flk-1 (VEGFR-2) expression.

METHODSTwo hundred and eight newborn Sprague Dawley rats were randomly divided into oxygen and air groups. The oxygen concentration in the oxygen group was alternated between 50% and 10% every 24 hours for 14 days. The control group were kept in room air environment. VEGF and Flk-1 expression was observed at 14, 18 and 25 days after birth in both exposed group and control group by immunohistochemical staining and semiquantitative RT-PCR. The status of retinal vasculature on day 4 after oxygen exposure was also observed. The retinas were dissected and stained by using a histochemical method for detecting adenosine diphosphatase (ADPase) activity, digital images of the retinas were captured and the peripheral avascular retina were measured. HE staining on methacrylate sections of eyes was used for counting the number of nuclei extending from retinal area into vitreous to identify extraretinal neovascularization. Numeric data were expressed as the mean +/- standard deviation (SD). Statistical calculations were performed using the SAS 8.1 statistical package. Differences in measured variables between experimental and control groups were determined using comparison of the means using two-way analysis of variance (ANOVA) statistical calculations and T-test. AP value less than 0.05 was regarded as significant.

RESULTS(1) The animal model was successfully established: the avascular areas of retina of 18-day-old rats were larger than those of the control group and the numbers of nuclei extending from retinal area into vitreous in exposed group were significantly higher compared to the control (P < 0.05). (2) The expression of VEGF and Flk-1 on the 14(th) day in the oxygen group was significantly stronger than that of the control group (P < 0.05). In the oxygen group, VEGF and Flk-1 expression was the strongest in the retina on the 18(th) day, the result had significant difference as compared with the 14(th) and 25(th) day (P < 0.05), and they were also stronger than that of the control group (P < 0.05). The expression of VEGF and Flk-1 decreased on the 25(th) day and had no significant difference as compared with the control group (P > 0.05). (3) Both VEGF-mRNA and Flk-1-mRNA significantly increased on the 14(th) day and the 18th day (P < 0.05). On the 25(th) day, the amounts of VEGF-mRNA and Flk-1-mRNA were similar between the control and oxygen group (P > 0.05).

CONCLUSIONFluctuation in oxygen is associated with the development of retinal neovascularization in the retinopathy. Increased expressions of VEGF and Flk-1 in the oxgen fluctuations-induced neovascularized retina suggested that VEGF and Flk-1 might play a critical role in the pathogenesis of ROP. The results also indicated the positive feedback in the pathogenesis of ROP that the synergistic interaction of VEGF and Flk-1 in the retinal vascular proliferation. These findings provide insight into the effect of repeated oxygen fluctuation on the development of severe ROP in preterm infants.

Animals ; Disease Models, Animal ; Humans ; Hyperoxia ; pathology ; Hypoxia ; pathology ; Infant, Newborn ; Oxygen ; adverse effects ; Rats ; Rats, Sprague-Dawley ; Retinal Neovascularization ; pathology ; Retinopathy of Prematurity ; pathology ; Vascular Endothelial Growth Factor A ; metabolism ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism

OBJECTIVETo examine the expression of mRNA of vascular endothelial growth factor (VEGF) in a rat model of hyperoxia-induced retinopathy and to investigate the role of VEGF in the process of neovascularization in retinopathy.

METHODSOne hundred fifty one-day-old neonatal Sprague-Dawley rats were randomly divided into hyperoxia-induced retinopathy and normal control groups. The rats in the retinopathy group were exposed to (80 +/- 2)% oxygen for 7 days and then replaced by room air. The rats in the control group were exposed to room air all the time of the experiment. The morphologic changes of retinal vessels were estimated by observing the vascular pattern in adenosine diphosphate ase (ADPase) stained retina flat mounts. The newborn vessels were quantified by haematoxylin and eosin staining. Reversal transcription-polymerase chain reaction (RT-PCR) was used to detect the VEGF mRNA expression.

RESULTSIn the retinopathy group at 7 days of age, most of central radial vessels became constricted and blocked, and central perfusion decreased obviously. After switching to room air exposure for 7 days (14 days of age), noticeable retinal neovascularization appeared. The expression of VEGF mRNA in the retinopathy group at 7 days of hyperoxia exposure was noticeably lower than in the control group, and increased gradually after switching to room air exposure. At 9 and 14 days of age, the expression of VEGF mRNA in the retinopathy group was noticeably higher than in the control group. The expression of retinal VEGF mRNA in the retinopathy group increased before neovascularization occurred, and decreased with regression of new vessels.

CONCLUSIONSHyperoxia exposure may decrease the transcription of VEGF mRNA and the growth of retinal blood vessels. The relative hypoxia after hyperxia withdrawal can up-regulate the transcription of VEGF mRNA, resulting in a significant retinal neovascularization. The abnormal expression of VEGF in the retina may play an important role in the development of neovascularization in retinopathy.

Animals ; Animals, Newborn ; Disease Models, Animal ; Female ; Humans ; Hyperoxia ; complications ; Infant, Newborn ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Retina ; pathology ; Retinal Neovascularization ; Retinopathy of Prematurity ; metabolism ; Vascular Endothelial Growth Factor A ; genetics

PURPOSE: To identify the unique pathologic findings of retinal angiomatous proliferation (RAP) in optical coherence tomography (OCT). METHODS: Retrospectively, 29 eyes of 25 patients with age-related macular degeneration and complicated RAP were analyzed. All 29 eyes had choroidal neovascularization (CNV) in the area of pigment epithelial detachment (PED) or adjacent to it, which was visible with fluorescein angiography or indocyanine green angiography. Cross-sectional images were obtained by OCT scanning through the CNV lesions. RESULTS: Six distinctive findings of OCT included drusen (100%), inner retinal cyst (80%), outer retinal cyst (68%), fibrovascular PED (84%), serous retinal detachment (40%), and PED (68%). CONCLUSIONS: Through analysis of OCT findings, we revealed six different types of lesions distinctive of RAP which may provide helpful diagnostic information for subsequent treatment and predicting the prognosis of RAP.
Aged ; Aged, 80 and over ; Female ; Follow-Up Studies ; Humans ; Macular Degeneration/*complications/diagnosis ; Male ; Middle Aged ; Reproducibility of Results ; Retina/*pathology ; Retinal Neovascularization/*diagnosis/etiology ; Retrospective Studies ; Severity of Illness Index ; Tomography, Optical Coherence/*methods

BACKGROUNDNeovascularization can cause vision loss in proliferative diabetic retinopathy (PDR) and may be affected by many factors. Stromal cell-derived factor-1 (SDF-1) is a potent stimulator of angiogenesis. The study was aimed to investigate the expression of SDF-1 and its correlation with vascular endothelial growth factor (VEGF) in the eyes with diabetic retinopathy.

METHODSThe levels of SDF-1 and VEGF were measured by enzyme-linked immunosorbent assay in the vitreous of 41 eyes of 41 patients with PDR and 12 eyes of 12 patients with idiopathic macular hole (IMH). Vitreous fluid samples and fibrovascular preretinal membranes were obtained at vitrectomy. SDF-1 and VEGF were localized using immunohistochemistry.

RESULTSThe vitreous concentration of VEGF was significantly higher in eyes with PDR ((2143.7 +/- 1685.21) pg/ml) than in eyes with IMH ((142.42 +/- 72.83) pg/ml, P < 0.001). The vitreous level of SDF-1 was also significantly higher in eyes with PDR ((306.37 +/- 134.25) pg/ml) than in eyes with IMH ((86.91 +/- 55.05) pg/ml, P < 0.001). The concentrations of both VEGF and SDF-1 were higher in eyes with active PDR than in eyes with inactive PDR. Panretinal photocoagulation (PRP) could decrease the SDF-1 levels in the vitreous of PDR patients. The vitreous concentration of SDF-1 correlated with that of VEGF in eyes with PDR (r = 0.61, P < 0.001). The costaining of SDF-1 and VEGF was confined to the vascular components in preretinal membranes.

CONCLUSIONSSDF-1 protein is highly expressed in both the vitreous and preretinal membranes of PDR patients; SDF-1 may be correlated with VEGF in angiogenesis in PDR.

Chemokine CXCL12 ; metabolism ; Diabetic Retinopathy ; metabolism ; pathology ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunohistochemistry ; Neovascularization, Pathologic ; metabolism ; physiopathology ; Retinal Perforations ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism ; Vitrectomy ; Vitreous Body ; metabolism

PURPOSE: To investigate which spectral domain optical coherence tomography (SD-OCT) findings predict visual outcome after anti-vascular endothelial growth factor (VEGF) treatment in neovascular age-related macular degeneration (NV-AMD). METHODS: We reviewed the medical records of patients with treatment-naive NV-AMD who underwent three or more consecutive anti-VEGF injections. The patients were divided into three groups according to their changes of visual acuity (VA); improved (group I), static (group S), or worsened (group W). We assessed the incidences and values of all available SD-OCT findings of these groups, compared these findings between the three groups and compared the initial values with the post-treatment values. RESULTS: Better initial VA and longer external limiting membrane (ELM) length were associated with less change in VA after anti-VEGF treatment. The initial VA was mildly correlated with initial photoreceptor inner and outer segment junction (IS/OS) length and initial ELM length. The final VA was also mildly correlated with the final IS/OS length and the final ELM length. VA was significantly changed after anti-VEGF treatment in groups W and I. With regard to incidence, disruption of the IS/OS (IS/OS-D), disruption of the ELM (ELM-D) and ELM length differed significantly between the three groups, particularly ELM-D. The incidences of IS/OS-D and ELM-D in group I were significantly lower than those in groups S and W, and those in group S were also lower than those in group W. The ELM length in group I was significantly longer than it was in groups S and W, and the ELM length in group S was longer than that for group W. However, these three findings did not change after the anti-VEGF treatment. CONCLUSIONS: Initial IS/OS-D, ELM length and particularly ELM-D can be useful predictors of the visual outcome after anti-VEGF treatment in NV-AMD patients.
Aged ; Aged, 80 and over ; Angiogenesis Inhibitors/*therapeutic use ; Choroidal Neovascularization/*drug therapy/physiopathology ; Female ; Humans ; Intravitreal Injections ; Male ; Middle Aged ; Ranibizumab/*therapeutic use ; Retinal Photoreceptor Cell Inner Segment/pathology ; Retinal Photoreceptor Cell Outer Segment/pathology ; Tomography, Optical Coherence ; Vascular Endothelial Growth Factor A/antagonists & inhibitors ; Visual Acuity/*physiology ; Wet Macular Degeneration/*drug therapy/physiopathology

PURPOSE: The goal of the present research was to study post-treatment changes in polypoidal choroidal vasculopathy (PCV) shown by optical coherence tomography (OCT). METHODS: The study included 12 patients with naive PCV. Photodynamic therapy and 3 consecutive intravitreal bevacizumab injections at 6-week intervals were given. Best corrected visual acuity, subretinal fluid (SRF), pigment epithelium detachment (PED), central macular thickness (CMT), and total macular volume (TMV) were measured before and after treatment as assessed by Stratus OCT3. RESULTS: After treatment, the SRF height decreased earlier than the PED height. The SRF diameter decreased with statistical significance. However, the PED diameter did not show a statistically significant improvement, persisting at pre-treatment levels. Both CMT and TMV decreased significantly after treatment. CONCLUSIONS: After PCV treatment, SRF and PED stabilized, as shown by OCT. However, the PED treatment response was both delayed and refractory compared to the SRF response. The small change in post-treatment PED diameter may suggest the possibility of PCV recurrence.
Aged ; Choroid/*pathology ; Choroid Diseases ; Choroidal Neovascularization/diagnosis/*drug therapy ; Disease Progression ; Female ; Fluorescein Angiography ; Follow-Up Studies ; Fundus Oculi ; Humans ; Male ; Photochemotherapy/*adverse effects ; Prognosis ; Retinal Detachment/diagnosis/*etiology ; Retinal Pigment Epithelium/*pathology ; Retrospective Studies ; *Subretinal Fluid ; Time Factors ; Tomography, Optical Coherence ; Visual Acuity