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Evangelos S Gragoudas

Publications and source records attributed to Evangelos S Gragoudas.

At least 19 recordsLinked to original sources

Proton beam irradiation for neovascular age-related macular degeneration.

OBJECTIVE: To evaluate safety and visual outcomes after proton therapy for subfoveal neovascular age-related macular degeneration (AMD). DESIGN: Randomized dose-ranging clinical trial. PARTICIPANTS: One hundred sixty-six patients with angiographic evidence of classic choroidal neovascularization resulting from AMD and best-corrected visual acuity of 20/320 or better. METHODS: Patients were assigned randomly (1:1) to receive 16-cobalt gray equivalent (CGE) or 24-CGE proton radiation in 2 equal fractions. Visual acuity was measured using standardized protocol refraction. Complete ophthalmological examinations, color fundus photography, and fluorescein angiography were performed before and 3, 6, 12, 18, and 24 months after treatment. MAIN OUTCOME MEASURE: Proportion of eyes losing 3 or more lines of vision from baseline. Kaplan-Meier statistics were used to compare cumulative rates of vision loss between the 2 treatment groups. RESULTS: At 12 months after treatment, 36 eyes (42%) and 27 eyes (35%) lost 3 or more lines of vision in the 16-CGE and 24-CGE groups, respectively. Rates increased to 62% in the 16-CGE group and 53% in the 24-CGE group by 24 months after treatment (P = 0.40). Radiation complications developed in 15.7% of patients receiving 16 CGE and 14.8% of patients receiving 24 CGE. CONCLUSIONS: No significant differences in rates of visual loss were found between the 2 dose groups. Proton radiation may be useful as an adjuvant therapy or as an alternative for patients who decline or are not appropriate for approved therapies.

Aged↗

Conservation treatment of the eye: Conformal proton reirradiation for recurrent uveal melanoma.

PURPOSE: To evaluate the outcomes of a second course of proton beam radiation therapy (PBRT) in patients with recurrent uveal melanoma. METHODS AND MATERIALS: Thirty-one patients received a second course of PBRT. The mean interval between the first and the second PBRT course was 50.2 months (range, 8-165 months). Most patients (87%) received 70 cobalt Gray equivalent (CGE) for both courses. Visual acuity was 20/200 or better in 30 patients initially and in 22 patients at the second treatment. The mean follow-up time after the second treatment was 50 months (range, 6-164 months). RESULTS: At the time of the last follow-up, 20 patients were classified as having no evidence of disease, defined as tumor regression or an absence of tumor progression. Nine eyes (29%) were enucleated because of local recurrence (n = 5) or intractable pain (n = 4). The 5-year eye retention rate was 55% (95% confidence interval: 25.2-77.4). Six of the 22 patients who retained the eye (27%) had useful vision (20/200 or better). CONCLUSIONS: A second course of PBRT for recurrent uveal melanoma to total doses between 118 and 140 CGE was associated with a relatively good probability of local control and a low enucleation rate. Although most patients lost vision, the majority were able to retain the reirradiated eye. Further evaluation is needed to assess metastasis-free survival of additional proton irradiation vs. enucleation after local recurrence.

Adult↗

Histologic correlation of in vivo optical coherence tomography images of the human retina.

PURPOSE: To correlate in vivo human retina optical coherence tomography (OCT)3 images with histology. DESIGN: Case series. METHODS: Linear OCT3 scans through the macula and optic nerve were obtained in three eyes of three patients who then underwent exenteration surgery for orbital cancers. OCT3 images were then correlated with histology. RESULTS: On histology, two eyes were normal, and one eye had dry macular degeneration. The plexiform layers on histology correlated with the green/yellow areas on the OCT3 scans, and the nuclear layers correlated with the black areas on the OCT3 scans. CONCLUSIONS: The authors are unaware of previous reports correlating histology to in vivo human retina OCT3 images. Our findings using human eyes are not different from previous animal studies, in that the plexiform layers are optically highly backscattering and the nuclear layers are not.

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Effect of intravitreal injection of ranibizumab in combination with verteporfin PDT on normal primate retina and choroid.

PURPOSE: To evaluate the effect of intravitreal injection of a monoclonal antibody fragment (ranibizumab, also known as rhuFab V2 and Lucentis; Genentech, S. San Francisco, CA) directed against vascular endothelial growth factor (VEGF) in combination with verteporfin photodynamic therapy (PDT) on normal primate retina and choroid. METHODS: Eight cynomolgus monkeys were treated with intravitreal ranibizumab in one eye and placebo in the other, alternating with verteporfin PDT in both eyes on a weekly basis for 6 to 7 weeks. Treatment effects were evaluated by color fundus photography, fluorescein angiography, and light and electron microscopy. RESULTS: Over the course of the study, increasing retinal pigment epithelial changes, with corresponding window defects, developed in both eyes of all animals on fluorescein angiography over the course of the study. No complications attributable to the intravitreal injection of ranibizumab were observed. Histologic analysis revealed a similar reduction in choriocapillaris density in the irradiated area of eyes treated with PDT alone compared with those that received combination treatment. CONCLUSIONS: In this limited study of normal monkey eyes, no severe adverse effects from the combination of intravitreal ranibizumab and verteporfin PDT were demonstrated compared with PDT alone.

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Dose-dependent effect of pitavastatin on VEGF and angiogenesis in a mouse model of choroidal neovascularization.

PURPOSE: To evaluate the relation between statin therapy, vascular endothelial growth factor (VEGF) expression, vascular leakage, and CNV size in experimentally induced choroidal neovascularization (CNV). METHODS: Wild-type (C57 Bl/6J) mice received pitavastatin 0.18 mg/kg per day (group 1), 1.8 mg/kg per day (group 2) or 18 mg/kg per day (group 3) for 3 days before laser-induced CNV and continued to receive the drug for 14 days. Serum total cholesterol levels were measured by spectrophotometry. Fluorescein angiograms were graded by masked observers. VEGF protein levels from retinal lysates were measured and CNV area was assessed by histology. RESULTS: Pitavastatin did not reduce total serum cholesterol at any of the doses used. The incidence rate ratios for development of clinically significant CNV leakage was 0.62 (95% CI, 0.46-0.84) for group 1, 0.56 (95% CI, 0.28-1.10) for group 2, and 1.22 (95% CI, 1.01-1.48) for group 3 (P=0.002, 0.09, and 0.04, respectively). Mean CNV area increased by 13%, 22%, and 95% in groups 1, 2, and 3, respectively (P>0.05). Normalized VEGF levels did not mirror the observed changes in fluorescein leakage and CNV area in histologic examination. CONCLUSIONS: Pitavastatin therapy for experimental CNV in wild-type mice resulted in reduced fluorescein leakage at a dose of 0.18 mg/kg per day. The higher dose of 18 mg/kg per day resulted in increased fluorescein leakage and a trend toward an increase in CNV size, indicating a potentiating effect in choroidal neovascular disease.

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Investigating the effect of ciliary body photodynamic therapy in a glaucoma mouse model.

PURPOSE: To investigate the morphologic and functional effects of verteporfin ciliary body photodynamic therapy (PDT) in a murine glaucoma model and normal mouse eyes. METHODS: A glaucomatous mouse strain, DBA/2J and a normal control mouse strain (C57BL/6) were used in the study. Verteporfin was injected intravenously at doses of 1.0 (DBA/2J) or 2.0 or 4.0 (C57BL/6) mg/kg. Transscleral irradiation of the ciliary body was performed with light at a wavelength of 689 nm delivered through an optical fiber, with irradiance of 1800 mW/cm2 and fluence of 100 J/cm2. Laser irradiation was applied for 360 degrees of the corneoscleral limbus in C57BL/6 normal mice and for 180 degrees in DBA/2J mice. Retreatment was performed in C57BL/6 normal mice that had been treated with 2.0 mg/kg of verteporfin at post-PDT day 7. One eye of each animal was treated, and the fellow eye served as the control. The morphologic effect of PDT on the ocular structures was assessed by light and electron microscopy. The IOP was measured using an applanation tonometer with a fiber-optic pressure sensor. Surviving retinal ganglion cells (RGCs) in DBA/2J mice eyes were retrogradely labeled with a neurotracer dye at 12 weeks after PDT. RESULTS: In all groups, almost all ciliary body blood vessels in the treated area were thrombosed 1 day after PDT. In DBA/2J mice, ciliary epithelium and stroma were severely damaged 1 day after PDT. The mean IOP in treated eyes was significantly reduced compared with that in the control eyes in all groups. The reduction of mean IOP in DBA/2J mouse eyes persisted for 7 weeks, although the mean IOP in normal mouse eyes treated with 2 or 4.0 mg/kg verteporfin returned to the level of the fellow control eyes by 7 and 17 days after treatment, respectively. The mean number of RGCs in the DBA/2J treated eyes was significantly higher than in control eyes. CONCLUSIONS: Ciliary body PDT resulted in morphologic changes in the ciliary body, significant reduction of IOP, and prevention of ganglion cell loss in a mouse glaucoma model. These results suggest that ciliary body PDT is a more selective cyclodestructive technique with potential clinical application in the treatment of glaucoma.

Animals↗

Identification of Chlamydia pneumoniae within human choroidal neovascular membranes secondary to age-related macular degeneration.

Age-related macular degeneration (AMD) is a leading cause of blindness in the United States, and increasing evidence suggests that it is an inflammatory disease. The prokaryotic obligate intracellular pathogen Chlamydia pneumoniae is emerging as a novel risk factor in cardiovascular disease, and recent sero-epidemiological data suggest that C. pneumoniae infection is also associated with AMD. In this study, we examined choroidal neovascular membrane (CNV) tissue from patients with neovascular AMD for the presence of C. pneumoniae and determined whether the pathogen can dysregulate the function of key cell types in ways that can cause neovascular AMD. Nine CNV removed from patients with neovascular AMD were examined for the presence of C. pneumoniae by immunohistochemistry (IHC) and polymerase chain reaction (PCR); in addition, we performed PCR on nine non-AMD eyes, and IHC on five non-AMD CNV, seven non-AMD eyes, and one internal limiting membrane specimen. Finally, human monocyte-derived macrophages and retinal pigment epithelial (RPE) cells were exposed to C. pneumoniae and assayed in vitro for the production of pro-angiogenic immunomodulators (VEGF, IL-8, and MCP-1). C. pneumoniae was detected in four of nine AMD CNV by IHC and two of nine AMD CNV by PCR, induced VEGF production by human macrophages, and increased production of IL-8 and MCP-1 by RPE cells. In contrast, none of the 22 non-AMD specimens showed evidence for C. pneumoniae. These data indicate that a pathogen capable of inducing chronic inflammation and pro-angiogenic cytokines can be detected in some AMD CNV, and suggest that infection may contribute to the pathogenesis of AMD.

Adult↗

An antisense oligodeoxynucleotide against vascular endothelial growth factor in a nonhuman primate model of iris neovascularization.

OBJECTIVE: To evaluate an antisense oligodeoxynucleotide (AS-ODN) targeted against vascular endothelial growth factor for its effects on ocular angiogenesis and its intraocular localization in a nonhuman primate model of iris neovascularization. METHODS: Bilateral laser retinal vein occlusion was performed in monkeys, followed by intravitreal injections of a vascular endothelial growth factor-specific AS-ODN or control. Serial fluorescein angiograms were graded in a masked manner to measure iris neovascularization. Localization was determined using a fluorescent-labeled AS-ODN and confocal microscopy on fixed tissue. RESULTS: Intravitreally injected vascular endothelial growth factor-specific AS-ODN localized to the retina, in the ganglion cell layer, inner nuclear layer, outer plexiform layer, photoreceptor outer segments, and retinal pigment epithelium. In 8 animals tested with 3microM ODN, AS-ODN-treated eyes had a significant reduction in iris neovascularization compared with control fellow eyes (P = .006, MIXOR analysis). Overall, in 17 animals tested across a range of ODN concentrations (0.1-50.0microM), AS-ODN-treated eyes were more likely to have lower iris neovascularization grades (P = .006, McNemar test) and the absence of iris neovascularization (P< .001, mixed-effects logistic regression model). CONCLUSION: Antisense ODNs that target vascular endothelial growth factor delivered to the retina via intravitreal injection reduced iris neovascularization in this model. Clinical Relevance Antisense ODNs against vascular endothelial growth factor may have therapeutic potential for neovascular eye diseases.

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Safety and efficacy of intravitreal injection of ranibizumab in combination with verteporfin PDT on experimental choroidal neovascularization in the monkey.

OBJECTIVE: To study the safety and efficacy of intravitreal injections of anti-vascular endothelial growth factor antibody fragment (ranibizumab [formerly known as rhuFabV2], Lucentis; Genentech, South San Francisco, Calif) in combination with intravenous verteporfin (Visudyne; Novartis, East Hanover, NJ) photodynamic therapy (PDT) on experimental choroidal neovascularization in the monkey eye. METHODS: Choroidal neovascularization was induced by laser injury in both eyes of cynomolgus monkeys and followed with weekly fundus photography and fluorescein angiography. Two weeks after induction, weekly treatments were initiated. These treatments included using either an intravitreal injection of ranibizumab (previously known as rhuFabV2) in combination with verteporfin PDT or a ranibizumab vehicle (placebo) in combination with verteporfin PDT (PDT only). Six animals (group 1) initially received intravitreal injections followed 1 week later by PDT. Four animals (group 2) initially received PDT followed 1 week later by intravitreal injection. Two animals (group 3) received injections and PDT on the same day at 2-week intervals. Photodynamic therapy was applied in all 3 groups every 2 weeks for 3 treatments with follow-up through 2 weeks after the last PDT treatment. Fluorescein angiograms were graded using a masked standardized protocol. The data were analyzed using the McNemar chi(2) test for matched pairs. RESULTS: No choroidal neovascularization leakage was observed in the eyes of animals treated with ranibizumab and PDT at day 21 or 42 after the start of the first treatment. Leakage persisted in eyes treated with PDT alone at 21 days (3 of 12 eyes) and 42 days (2 of 12 eyes). At all time points studied, the ranibizumab and PDT-treated eyes experienced better angiographic outcomes than the eyes receiving PDT alone. CONCLUSION: These preliminary data indicate that an intravitreal ranibizumab injection in combination with verteporfin PDT (ranibizumab and PDT) causes a greater reduction in angiographic leakage than PDT and intravitreal vehicle injection (PDT only) in experimental choroidal neovascularization. CLINICAL RELEVANCE: This combination therapy can potentially offer a new treatment modality for choroidal neovascularization in patients with macular degeneration and other diseases.

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Uveal melanoma: proton beam irradiation.

Over the past two decades, radiotherapy has replaced enucleation as the standard treatment for uveal melanoma. Although this method does not alter survival, preservation of the globe and, in some instances, visual function, is achieved. This article presents the authors' and other investigators' experience with proton therapy.

Follow-Up Studies↗

Treatment of metastatic tumors of the choroid with proton beam irradiation.

OBJECTIVE: To describe the clinical outcomes of patients treated by proton beam irradiation for choroidal metastatic tumors. DESIGN: Noncomparative case series. PARTICIPANTS: A retrospective chart review was performed on a series of 63 patients (76 eyes) with choroidal metastases treated with proton beam therapy between December 1989 and September 2000. METHODS: Patients were treated with 2 fractions of 14 cobalt gray equivalents (CGEs) (CGE = proton Gy x relative biological effectiveness 1.1), each using a nonoperative "light-field" technique. Ophthalmologic follow-up was available for 46 patients (55 eyes), with a mean follow-up time of 10 months. The medical record or the Social Security Death Index was used to obtain survival status, which was available in 94% of cases. MAIN OUTCOME MEASURES: Tumor regression, recurrence, treatment-associated complications, and visual acuity were evaluated by ophthalmologic examination and ultrasonography. Eye retention and length of survival also were assessed. RESULTS: At the time of ocular diagnosis, 49 patients reported a history of a primary cancer. Median survival time after ocular diagnosis was 16 months through May 2003. Most choroidal metastases were dome shaped (62%) and located at the posterior pole (95%). Mean tumor height was approximately 3.5 mm, and serous retinal detachment was seen in 63% of cases. Eighty-four percent of treated tumors regressed completely within 5 months of treatment, and none of these recurred. Retinal detachment resolved in 82% of patients within 3.8 months after treatment, and visual acuity was preserved or improved in 47% of the patients. Complications occurred in 56% of cases and included madarosis, keratitis, dry eye syndrome, cataract, neovascular glaucoma, chorioretinal atrophy, radiation papillopathy, and radiation maculopathy. None of the treated eyes required enucleation. CONCLUSIONS: Proton beam irradiation is a useful therapeutic approach for choroidal metastases; it allows retention of the globe, achieves a high probability of local tumor control, and helps to avoid pain and visual loss. Although complications occur in most cases, many of these are minor and are not associated with a change in function. This modality is accurate and efficient, because it only entails 2 treatment fractions and does not require surgery for tumor localization.

Adult↗

Pegaptanib for neovascular age-related macular degeneration.

BACKGROUND: Pegaptanib, an anti-vascular endothelial growth factor therapy, was evaluated in the treatment of neovascular age-related macular degeneration. METHODS: We conducted two concurrent, prospective, randomized, double-blind, multicenter, dose-ranging, controlled clinical trials using broad entry criteria. Intravitreous injection into one eye per patient of pegaptanib (at a dose of 0.3 mg, 1.0 mg, or 3.0 mg) or sham injections were administered every 6 weeks over a period of 48 weeks. The primary end point was the proportion of patients who had lost fewer than 15 letters of visual acuity at 54 weeks. RESULTS: In the combined analysis of the primary end point (for a total of 1186 patients), efficacy was demonstrated, without a dose-response relationship, for all three doses of pegaptanib (P<0.001 for the comparison of 0.3 mg with sham injection; P<0.001 for the comparison of 1.0 mg with sham injection; and P=0.03 for the comparison of 3.0 mg with sham injection). In the group given pegaptanib at 0.3 mg, 70 percent of patients lost fewer than 15 letters of visual acuity, as compared with 55 percent among the controls (P<0.001). The risk of severe loss of visual acuity (loss of 30 letters or more) was reduced from 22 percent in the sham-injection group to 10 percent in the group receiving 0.3 mg of pegaptanib (P<0.001). More patients receiving pegaptanib (0.3 mg), as compared with sham injection, maintained their visual acuity or gained acuity (33 percent vs. 23 percent; P=0.003). As early as six weeks after beginning therapy with the study drug, and at all subsequent points, the mean visual acuity among patients receiving 0.3 mg of pegaptanib was better than in those receiving sham injections (P<0.002). Among the adverse events that occurred, endophthalmitis (in 1.3 percent of patients), traumatic injury to the lens (in 0.7 percent), and retinal detachment (in 0.6 percent) were the most serious and required vigilance. These events were associated with a severe loss of visual acuity in 0.1 percent of patients. CONCLUSIONS: Pegaptanib appears to be an effective therapy for neovascular age-related macular degeneration. Its long-term safety is not known.

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Selective photodynamic therapy by targeted verteporfin delivery to experimental choroidal neovascularization mediated by a homing peptide to vascular endothelial growth factor receptor-2.

OBJECTIVE: To evaluate the feasibility, efficacy, and selectivity of photodynamic therapy (PDT) using targeted delivery of verteporfin to choroidal neovascularization (CNV) in the rat laser-injury model of CNV. METHODS: We performed PDT in rat eyes on experimental CNV and normal retina and choroid using verteporfin conjugates. A targeted verteporfin conjugate was made by conjugating verteporfin (after isolation from its liposomal formulation) to a modified polyvinyl alcohol (PVA) polymer (verteporfin-PVA) followed by linkage to the peptide ATWLPPR known to bind the receptor for vascular endothelial growth factor, VEGFR2. The verteporfin-PVA conjugate served as a control. We performed fluorescent fundus angiography to determine the optimal timing of light application for PDT using the conjugates. Closure of CNV was assessed angiographically and graded in a masked standardized fashion. We used standardized histological grading to compare the effects on normal retina and choroid. RESULTS: The verteporfin-PVA conjugation ratio was on average 28:1. The conjugate retained typical emission/excitation spectra and photosensitizing activity and was as efficient as an equivalent amount of verteporfin. Peak intensity of targeted verteporfin in CNV was detected angiographically at 1 hour after intravenous injection. Photodynamic therapy using targeted verteporfin (3 or 4.5 mg/m2) with light application 1 hour after drug injection showed angiographic closure of all treated CNV (17/17) 1 day after treatment. Photodynamic therapy using verteporfin-PVA at the same drug dose achieved closure in 18 of 20 CNV. Histological examination after PDT of normal retina and choroid using targeted verteporfin and irradiation at 1 hour showed minimal effect on retinal pigment epithelium and no injury to photoreceptors, whereas PDT using verteporfin-PVA resulted in retinal pigment epithelium necrosis and mild damage to photoreceptors. CONCLUSIONS: Verteporfin bound to the targeting peptide, ATWLPPR, retained its spectral and photosensitizing properties. Angiography demonstrated localization of the targeted verteporfin 1 hour after injection. Photodynamic therapy using targeted verteporfin and the control conjugate were more effective in causing CNV closure than standard liposomal verteporfin. The targeted verteporfin resulted in more selective treatment than the control conjugate or standard verteporfin. These results suggest that targeted PDT strategies based on selective expression of receptors on CNV vasculature may improve current therapy. CLINICAL RELEVANCE: Targeted PDT for CNV is feasible and may offer a qualitative improvement in current treatments for patients with age-related macular degeneration. This study provides the basis for further preclinical studies of targeted PDT strategies and subsequent clinical trials.

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MRI of blood volume with superparamagnetic iron in choroidal melanoma treated with thermotherapy.

Functional magnetic resonance imaging (MRI) with a new intravascular contrast agent, monocrystalline iron oxide nanoparticles (MION), was applied to assess the effect of transpupillary thermotherapy in a rabbit model of choroidal melanoma. 3D-spoiled gradient recalled sequences were used for quantitative assessment of blood volume. The MRI-parameters were 5/22/35 degrees (time of repetition (TR)/echo delay (TE)/flip angle (FA)) for T(1)- and 50/61/10 degrees for T(2)-weighted sequences. Images were collected before and at different times after MION injection. In all untreated tissues studied, MION reduced the T(2)-weighted signal intensity within 0.5 h and at 24 h (all p <== 0.012), whereas no significant changes were detected in treated tumors. T(1)-weighted images also revealed differences of MION-related signal changes between treated tumors and other tissues, yet at lower sensitivity and specificity than T(2). The change of T(2)-weighted MRI signal caused by intravascular MION allows early distinction of laser-treated experimental melanomas from untreated tissues. Further study is necessary to determine whether MRI can localize areas of tumor regrowth within tumors treated incompletely.

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