202 results on '"de Juan E Jr"'
Search Results
2. Silicone oil injection after failed primary vitreous surgery in severe ocular trauma
- Author
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Antoszyk, A.N., McCuen, B.W., 2d., de Juan, E., Jr., and Machemer, R.
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Eye ,Retinal detachment -- Complications ,Silicones in medicine -- Statistics ,Health - Abstract
In 42 cases of retinal detachment following a failed vitrectomy (a procedure to remove the contents of the vitreous chamber of the eye), the re-attachment of the retina was successful in 50 percent of the cases. Twenty-eight percent had vision of 5/200 or better. Many patients who had vision of 5/200 or better at six months lost acuity in the three years following, usually due to further retinal detachments or swelling of the cornea. Only 12 percent of the patients had vision of 5/200 or better at the last examination.
- Published
- 1989
3. Progress in the treatment of posterior segment trauma.
- Author
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MacCumber, Mathew W., de Juan, Eugene, MacCumber, M W, and de Juan, E Jr
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- 1994
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4. Rate-dependent, nonlinear photoablation of ocular tissue at 308 nm.
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Schallen, Eric H., Awh, Carl C., De Juan, Eugene, Schallen, E H, Awh, C C, and de Juan, E Jr
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- 1994
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5. Clinical results with the model 1IRP implant.
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Humayun, M., Yanai, D., Greenberg, R.J., Little, J., Mech, B.V., Mahadevappa, M., Weiland, J.D., Fujii, G.Y., and de Juan, E., Jr.
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- 2004
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6. Electrical stimulation of retina in blind humans.
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Weiland, J.D., Yanai, D., Mahadevappa, M., Williamson, R., Mech, B.V., Fujii, G.Y., Little, J., Greenberg, R.J., de Juan, E., Jr., and Humayun, M.S.
- Published
- 2003
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7. Cortical response after chronic electrical stimulation of canine retina.
- Author
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Mahadevappa, M., Weiland, J.D., Guven, D., Fujii, G.Y., Mech, B.V., Greenberg, R.J., de Juan, E., Jr., and Humayun, M.S.
- Published
- 2003
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8. Chronic electrical stimulation of the canine retina.
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Weiland, J.D., Fujii, G.Y., Mahadevappa, M., Greenberg, R.J., Tameesh, M., Guven, D., de Juan, E., Jr., and Humayun, M.S.
- Published
- 2002
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9. Macular vessel density in central retinal artery occlusion with retinal arterial cannulation.
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Soga N, Tanaka S, Inoue M, Inoue T, Hayashi A, de Juan E Jr, and Kadonosono K
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- Humans, Cross-Sectional Studies, Retina diagnostic imaging, Computed Tomography Angiography, Retinal Artery Occlusion diagnostic imaging, Vision, Low
- Abstract
To characterize and compare macular vessel density in central retinal artery occlusion (CRAO) eyes with retinal arterial cannulation and CRAO eyes with standard treatment. This study was Cross-sectional, observational study. Twenty-two eyes with nonarteric CRAO which underwent retinal arterial cannulation and 19 eyes with nonarteric CRAO with standard treatment were included. Optical coherent tomography angiography (OCTA)-based macular vessel density and visual acuity were examined. The dynamic ranged-based normalized rates of vessel density was compared within each group at the first visit to the clinic and 7 days after the onset. Macular vessel density in cannulation group was significantly better at 7 days after the onset than that at the first visit (3.73 ± 3.02 mm
-1 vs. 7.89 ± 1.02 mm-1 , P = 0.0001), while there wasn't significant improvement of macular vessel density in standard treatment group at 7 days after the onset (2.13 ± 1.62 mm-1 vs. 2.89 ± 0.22 mm-1 , P = 0.067). At one month after the onset, mean LogMAR visual acuity in CRAO eyes with cannulation significantly improved compared with that at the first visit after the onset (1.678 vs. 0.979, P = 0.00012). Macular vessel density loss in CRAO eyes was improved by retinal arterial cannulation. Early intervention of retinal arterial cannulation is useful for minimizing visual impairment in CRAO eyes., (© 2023. The Author(s).)- Published
- 2023
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10. Development of the Port Delivery System with ranibizumab for neovascular age-related macular degeneration.
- Author
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Adamis AP and de Juan E Jr
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- Angiogenesis Inhibitors therapeutic use, Antibodies, Monoclonal therapeutic use, Humans, Intravitreal Injections, Ranibizumab therapeutic use, Treatment Outcome, Diabetic Retinopathy drug therapy, Macular Degeneration drug therapy, Macular Edema drug therapy, Wet Macular Degeneration drug therapy
- Abstract
Purpose of Review: This review provides background on the remaining unmet needs with antivascular endothelial growth factor (VEGF) therapies for the treatment of neovascular age-related macular degeneration (nAMD). We also discuss the developmental story of the Port Delivery System with ranibizumab (PDS; SUSVIMO, Genentech, Inc., South San Francisco, CA, USA)., Recent Findings: Real-world studies have shown that undertreatment is a major reason for continued vision loss in the anti-VEGF era. As a result, there is a need for long-acting anti-VEGF treatment options for patients with nAMD, diabetic macular edema, and other retinal diseases. The PDS is a solid state, refillable, intraocular long-acting drug delivery system that continuously delivers a customized formulation of ranibizumab into the vitreous for 6 months. In a phase 3 trial, the PDS showed equivalent visual acuity improvements with monthly ranibizumab injections in patients with nAMD and adverse events associated with the PDS were well understood and manageable., Summary: The PDS is the first US Food and Drug Administration-approved treatment for nAMD that provides continuous delivery of an anti-VEGF molecule. The PDS offers a unique drug delivery system that has the potential to serve as a platform to be used with other molecules in the future., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)
- Published
- 2022
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11. Endovascular surgery in the field of ophthalmology.
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Kadonosono K, Hayashi A, and de Juan E Jr
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- Fibrinolytic Agents, Humans, Tissue Plasminogen Activator, Visual Acuity, Vitrectomy, Ophthalmology, Retinal Vein, Retinal Vein Occlusion diagnosis, Retinal Vein Occlusion drug therapy, Retinal Vein Occlusion surgery
- Abstract
In this article, we provide an overview of the current perspectives on endovascular surgery in ophthalmology, including a description of the various approaches, recent clinical results and future prospects. Experimental studies of endovascular surgery in ophthalmology started in the 1980s; since then, a considerable amount of research has been done to develop the procedure for clinical use. During the past two decades endovascular surgery has been performed on eyes with retinal vascular disorders, including central retinal vein occlusion and central retinal artery occlusion. The first endovascular surgery on human eyes was performed in 1998 on a patient with central retinal vein occlusion (CRVO). The most recent techniques used in retinal endovascular surgery involve manual injection of liquid agents such as tissue plasminogen activator into major retinal vessels using a 47 or 48-gauge micro-needle. New technology using a bimanual procedure and digitally assisted vitrectomy systems enables surgeons to perform this delicate procedure more effectively. Recent results reported from a number of researchers corroborate the effectiveness of the procedure. Endovascular surgery is one of the latest techniques in the field of ophthalmology and has garnered significant interest from vitreoretinal surgeons. However, it is also at the limit of what surgeons are able to accomplish with manual precision. There is still much to learn and improve to maximize the potential of this approach. The combination of skills as a surgeon, sound science, objective clinical evidence and cutting edge technology will lead to improvements in this field.
- Published
- 2021
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12. ADVERSE EVENTS OF THE ARGUS II RETINAL PROSTHESIS: Incidence, Causes, and Best Practices for Managing and Preventing Conjunctival Erosion.
- Author
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Rizzo S, Barale PO, Ayello-Scheer S, Devenyi RG, Delyfer MN, Korobelnik JF, Rachitskaya A, Yuan A, Jayasundera KT, Zacks DN, Handa JT, Montezuma SR, Koozekanani D, Stanga PE, da Cruz L, Walter P, Augustin AJ, Chizzolini M, Olmos de Koo LC, Ho AC, Kirchhof B, Hahn P, Vajzovic L, Iezzi R Jr, Gaucher D, Arevalo JF, Gregori NZ, Grisanti S, Özmert E, Yoon YH, Kokame GT, Lim JI, Szurman P, de Juan E Jr, Rezende FA, Salzmann J, Richard G, Huang SS, Merlini F, Patel U, Cruz C, Greenberg RJ, Justus S, Cinelli L, and Humayun MS
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- Conjunctival Diseases epidemiology, Conjunctival Diseases prevention & control, Europe epidemiology, Female, Humans, Incidence, Male, Middle Aged, Postoperative Complications epidemiology, Postoperative Complications prevention & control, Prosthesis Implantation methods, Retrospective Studies, United States epidemiology, Conjunctiva surgery, Conjunctival Diseases etiology, Postoperative Complications etiology, Prosthesis Implantation adverse effects, Retinitis Pigmentosa surgery, Visual Prosthesis adverse effects
- Abstract
Purpose: To analyze and provide an overview of the incidence, management, and prevention of conjunctival erosion in Argus II clinical trial subjects and postapproval patients., Methods: This retrospective analysis followed the results of 274 patients treated with the Argus II Retinal Prosthesis System between June 2007 and November 2017, including 30 subjects from the US and European clinical trials, and 244 patients in the postapproval phase. Results were gathered for incidence of a serious adverse event, incidence of conjunctival erosion, occurrence sites, rates of erosion, and erosion timing., Results: Overall, 60% of subjects in the clinical trial subjects versus 83% of patients in the postapproval phase did not experience device- or surgery-related serious adverse events. In the postapproval phase, conjunctival erosion had an incidence rate of 6.2% over 5 years and 11 months. In 55% of conjunctival erosion cases, erosion occurred in the inferotemporal quadrant, 25% in the superotemporal quadrant, and 20% in both. Sixty percent of the erosion events occurred in the first 15 months after implantation, and 85% within the first 2.5 years., Conclusion: Reducing occurrence of conjunctival erosion in patients with the Argus II Retinal Prosthesis requires identification and minimization of risk factors before and during implantation. Implementing inverted sutures at the implant tabs, use of graft material at these locations as well as Mersilene rather than nylon sutures, and accurate Tenon's and conjunctiva closure are recommended for consideration in all patients.
- Published
- 2020
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13. The Bionic Eye: A Quarter Century of Retinal Prosthesis Research and Development.
- Author
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Humayun MS, de Juan E Jr, and Dagnelie G
- Abstract
This article describes the history of visual prostheses, with emphasis on the development of the Argus II retinal prosthesis system (Second Sight Medical Products, Inc., Sylmar, CA). A brief overview of cortical electrical stimulation in the blind is provided, followed by an account of the design and development of retinal stimulation equipment at the Duke Eye Center in the late 1980s; the first human intraoperative tests there and the subsequent 8 years of tests at the Wilmer Eye Institute; the transfer of the project to the Doheny Eye Institute at the University of Southern California and the founding of Second Sight Medical Products; and the development and clinical trials of the Argus I and Argus II systems. In a series of vignettes, we pay tribute to the many colleagues and patient volunteers without whose help the work would not have been possible., (Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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14. Same-Day Versus Next-Day Repair of Fovea-Threatening Primary Rhegmatogenous Retinal Detachments.
- Author
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Gorovoy IR, Porco TC, Bhisitkul RB, de Juan E Jr, Schwartz DM, and Stewart JM
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- Adult, Aged, Female, Fovea Centralis physiopathology, Humans, Male, Middle Aged, Retinal Detachment physiopathology, Retrospective Studies, Time Factors, Time-to-Treatment, Treatment Outcome, Visual Acuity physiology, Fovea Centralis surgery, Retinal Detachment surgery, Scleral Buckling, Vitrectomy
- Abstract
Purpose: To evaluate the outcomes of same-day versus next-day repair of fovea-threatening rhegmatogenous retinal detachments (FT RRD)., Design: Retrospective, multi-surgeon observational case series., Methods: Operative reports and medical records were reviewed to evaluate a number of visual and anatomic outcomes, including presenting features, intraoperative complications, and postoperative results in the repair of primary FT RRD undergoing same-day versus next-day repair with scleral buckling, pars plana vitrectomy, or both procedures., Participants: A total of 96 consecutive patients (43 same-day, 45 next-day, and eight two days later) were compared., Results: There was no statistically significant difference in visual outcomes between same-day and next-day repair at postoperative months 3 and 6 and at last follow-up (month 3 mean BCVA 20/30 same day; 20/32 next day; p = 0.82). Preoperative vision was strongly correlated with postoperative acuity. Effect of differences in length or type of visual symptoms, location of RRD, gender, or lens status on postoperative month 3 best-corrected visual acuity (BCVA) was not statistically significant. Overall, 85% of patients had a BCVA of 20/40 or better at postoperative month 3. Reoperation rate and intraoperative complications were not statistically different between the two groups. Re-attachment was achieved in all but one patient in both groups. Time in the operating room was longer for same-day surgery (2.98 ± 0.46 hours) compared to next-day surgery (2.54 ± 0.38 hours) (p < 0.001), which was statistically significant even when factoring in the type of surgery performed. However, one case did progress to a macula-off detachment in a superior RRD with breaks found in lattice degeneration., Conclusion: Next-day surgery provided equivalent visual outcomes. Emergent, same-day surgery has logistical and resource implications as it may be more expensive, may necessitate rescheduling of previously booked cases, and may limit preoperative examination by the surgeon and perioperative team.
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- 2016
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15. Extraction of retinal tacks from subjects implanted with an epiretinal visual prosthesis.
- Author
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de Juan E Jr, Spencer R, Barale PO, da Cruz L, and Neysmith J
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- Aged, Choroideremia therapy, Female, Fluorescein Angiography, Humans, Male, Middle Aged, Prosthesis Implantation, Retinitis Pigmentosa therapy, Wound Healing, Device Removal, Electrodes, Implanted, Retina surgery, Surgical Fixation Devices, Visual Prosthesis
- Abstract
Background: Retinal tacks, first developed for the treatment of complex retinal detachments, have more recently been used for the fixation of epiretinal electrode arrays as part of implanted visual prostheses. Here, we report on the clinical experience of extracting four such tacks after chronic implantation. The ability to safely extract retinal tacks ensures that epiretinal devices can be repositioned or removed if necessary., Methods: Custom-built, titanium alloy retinal tacks were mechanically removed from the posterior coats after prolonged implantation (up to 19 months). The resulting wound was characterized by clinical evaluation, fundus photography, and fluorescein angiography while being monitored for stability over time. The wounds were also compared to earlier published reports of the healing response around retinal tacks in human subjects., Results: Tack extraction was accomplished successfully, without complication, in all four subjects. The wound site was readily identified by pale scar tissue. No change in the wound size or appearance was noted over many months of post-operative observation (up to 22 months after explant). No adverse effects on overall ocular health were detected., Conclusion: Extraction of retinal tacks from subjects implanted with epiretinal prostheses can be performed without significant complication. The long-term healing response appears to be stable and localized in eyes afflicted with retinitis pigmentosa or choroideremia. There was also minimal, if any, impact on the local circulatory system. These cases suggest that the use of retinal tacks for anchoring epiretinal visual prostheses does not preclude safe repositioning or removal of the device more than a year after implant.
- Published
- 2013
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16. Effect of intravitreal bevacizumab on intraocular pressure in a case of severe chronic hypotony.
- Author
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Trager Cabrera MJ, Borirakchanyavat S, and De Juan E Jr
- Abstract
Purpose: Chronic severe hypotony is associated with many serious ocular consequences, including phthisis. This case illustrates a possible new therapy for chronic hypotony., Methods: This study is a case report of a 75-year-old man who had undergone trabeculectomy followed by multiple retinal surgeries and developed chronic hypotony in the left eye for more than 1 year., Results: Treatment with intravitreal bevacizumab led to an elevation of intraocular pressure to 8 mmHg 1 week later. Hypotony returned within 2 weeks (2 mmHg) and variably remained for 2 months (0-10 mmHg) until a repeat injection of intravitreal bevacizumab resulted in another elevation in intraocular pressure, which was sustained (5-8 mmHg over 2 months). We postulate that antivascular endothelial growth factor therapy may influence aqueous production through restoration of tight junctions in the nonpigmented ciliary epithelium. Vascular endothelial growth factor and antivascular endothelial growth factor therapies have been demonstrated to modulate tight junctions in many other tissues in the body, including retinal pigment epithelium, ovarian tissue, vascular endothelium, liver, and brain vasculature., Conclusion: We postulate that antivascular endothelial growth factor therapy may play a role in treating hypotony by enhancing the function of tight junctions in the ciliary body and restoring aqueous production. Further studies are necessary to better clarify the influence of antivascular endothelial growth factor on intraocular pressure and aqueous production.
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- 2010
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17. Subretinal delivery of immunoglobulin G with gold nanoparticles in the rabbit eye.
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Hayashi A, Naseri A, Pennesi ME, and de Juan E Jr
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- Animals, Cell Culture Techniques, Cell Proliferation drug effects, Electrophoresis, Polyacrylamide Gel, Immunoenzyme Techniques, Metal Nanoparticles ultrastructure, Microscopy, Electron, Transmission, Photoreceptor Cells, Vertebrate drug effects, Photoreceptor Cells, Vertebrate ultrastructure, Rabbits, Retina ultrastructure, Retinal Pigment Epithelium drug effects, Retinal Pigment Epithelium ultrastructure, Drug Delivery Systems, Gold, Immunoconjugates administration & dosage, Immunoglobulin G administration & dosage, Metal Nanoparticles administration & dosage, Retina drug effects
- Abstract
Purpose: To examine the feasibility of subretinal delivery of immunoglobulin G (IgG) adsorbed onto gold nanoparticles (GNPs) and its histologic distribution in the rabbit retina after the injection., Methods: Goat IgG was adsorbed onto GNPs electrostatically. Goat IgG-adsorbed GNPs or buffer with goat IgG was injected into the subretinal space of rabbit eyes and followed up for 3 months by examination of fundus photographs, immunohistochemistry against goat IgG, and transmission electron microscopy (TEM). Human retinal pigment epithelial cells (ARPE-19 cells) were cultured, and cell proliferation with or without GNPs was assayed., Results: At 1 week after the subretinal injection of goat IgG-adsorbed GNPs, retinal degeneration was observed in the outer retina, and goat IgG was immunolabeled in the retinal pigment epithelium (RPE) and the photoreceptor cells. TEM showed GNPs located in the outer segments and in the lysosomes in the RPE at 1 month and no apparent cytotoxicity of the RPE. There were no inhibitory effects of GNPs on proliferation of ARPE-19 cells., Conclusions: Goat IgG was successfully delivered into photoreceptor cells and RPE using GNPs, though retinal degeneration in the outer retina occurred in this model. This might be an alternative drug delivery method to photoreceptors and RPE.
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- 2009
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18. Helical intravitreal triamcinolone acetonide implant: a 6-month surgical feasibility study in rabbits.
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Mello-Filho PA, Guven D, Beeley NR, de Juan E Jr, and Erickson SR
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- Animals, Feasibility Studies, Follow-Up Studies, Glucocorticoids adverse effects, Intraoperative Complications, Postoperative Complications, Rabbits, Retina drug effects, Retina pathology, Sclerostomy methods, Triamcinolone Acetonide adverse effects, Drug Implants, Glucocorticoids administration & dosage, Triamcinolone Acetonide administration & dosage, Vitreous Body drug effects
- Abstract
Background and Objective: To investigate the surgical feasibility and safety of a long-term intravitreal triamcinolone acetonide (TA) sustained delivery system., Materials and Methods: Pigmented rabbits were implanted with sustained-release formulations containing 925 microg of TA within a non-biodegradable polymer coating: Dose A (n = 15) with a slow delivery rate of 1 to 2 microg/day and Dose B (n = 15) releasing 3 to 5 microg/day. Additionally, a control group (n = 10) using a device coated with polymer only was implanted. The devices were surgically implanted through a 30-gauge sclerotomy into the vitreous cavity. The animals were clinically observed for up to 6 months after the surgery with complete ophthalmologic examinations. Histologic evaluation of a subset of eyes was performed at the conclusion of the study., Results: Implants were successfully implanted in all 40 eyes. Ocular examinations revealed excellent implant tolerability. In all eyes, there was no significant postoperative inflammation at 1 week of follow-up. There was no increase in intraocular pressure during the follow-up period and histologic evaluation demonstrated no significant abnormalities. Minimal and localized vitreous hemorrhage was observed in 22.5% of implanted eyes and mostly cleared at 1 month after surgery. During the 6 months of follow up, localized lens opacities associated with physical implant contact developed in 66.6% of eyes., Conclusion: The surgical procedure using the intravitreal TA sustained delivery device is feasible. Surgical complications were generally mild, with lens opacities attributable to unique anatomical features of the rabbit eye. Long-term follow-up and histology revealed excellent implant tolerability.
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- 2009
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19. A novel method to oxygenate intraocular irrigation fluids with an in-line oxygenator.
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Khurana RN, Chang YH, Barnes AC, Fujii GY, De Juan E Jr, and Humayun MS
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- Drug Combinations, Ophthalmology methods, Ringer's Lactate, Acetates administration & dosage, Isotonic Solutions administration & dosage, Minerals administration & dosage, Ophthalmic Solutions administration & dosage, Oxygen administration & dosage, Oxygenators, Sodium Chloride administration & dosage, Therapeutic Irrigation
- Abstract
Purpose: We describe a novel method to oxygenate intraocular irrigation solutions involving an in-line oxygenator., Methods: Either lactated Ringer (LR) solution or balanced salt solution (BSS) was oxygenated with the FE390 Stainless In-line Oxygenation Assembly (Beer, Beer, and More Beer, Concord, CA). After running a 100-mL of solution through the in-line oxygenator, oxygen saturation was measured with a dissolved oxygen meter. A control experiment involving the oxygenator without oxygen perfusion was performed. Paired t-tests were used to compare oxygen saturation changes before and after oxygenation., Results: In comparison with the original BSS, there was an increase in oxygen saturation of 162 +/- 47% (n = 40; P < 0.05). Without oxygenation perfusion, there was only a 24 +/- 14% (n = 40) increase in oxygen levels in BSS, which was significantly lower than that in treated BSS (P < 0.05). In comparison with the original LR solution, there was an increase in oxygen saturation of 208 +/- 21% (n = 40; P < 0.05). Without oxygenation perfusion, there was only a 21 +/- 9% (n = 40) gain in oxygen saturation in the control LR solution, which was statistically lower as well (P < 0.05)., Conclusion: The in-line oxygenator is an efficient tool for oxygenating BSS and LR solution. It represents a potential efficient and convenient method to oxygenate irrigating solutions for vitreoretinal surgeries.
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- 2007
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20. Effect of oxygenated intraocular irrigation solutions on the electroretinogram after vitrectomy.
- Author
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Javaheri M, Fujii GY, Rossi JV, Panzan CQ, Yanai D, Lakhanpal RR, Maia M, Khurana RN, Guven D, De Juan E Jr, and Humayun MS
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- Acetates administration & dosage, Animals, Bicarbonates administration & dosage, Dark Adaptation, Drug Combinations, Glutathione administration & dosage, Isotonic Solutions administration & dosage, Male, Minerals administration & dosage, Oxygenators, Photic Stimulation, Postoperative Period, Rabbits, Ringer's Lactate, Sodium Chloride administration & dosage, Electroretinography drug effects, Ophthalmic Solutions administration & dosage, Oxygen administration & dosage, Retina physiology, Vitrectomy
- Abstract
Purpose: To investigate the effect of oxygenated intraocular irrigating solutions on electroretinograms (ERGs) for postvitrectomy rabbits., Methods: Eight groups of five rabbits each underwent pars plana vitrectomy on the right eye; the left eye of each rabbit served as control. The intraocular irrigating solutions were balanced salt solution (BSS), BSS-plus, BSS + oxygen (BSS + O2), BSS-plus + O2, and combinations of each with the addition of endoillumination (L). All animals were evaluated by single-flash scotopic electroretinography on the operated and nonoperated eyes before surgery and at 1 hour, 1 day, 1 week, and 1 month after surgery by an unmasked observer. The main outcome measures were dark-adapted b-wave amplitudes of operated eye/nonoperated eye ratios. The results for the different groups were compared by analysis of variance., Results: Mean dark-adapted b-wave amplitudes of operated eye/nonoperated eye ratios +/- SD for BSS-plus and BSS-plus + O2 before surgery and 1 hour, 1 day, 1 week, and 1 month after surgery were 1.01 +/- 0.09, 0.50 +/- 0.11, 0.95 +/- 0.11, 0.97 +/- 0.11, and 0.99 +/- 0.08 and 0.98 +/- 0.08, 0.59 +/- 0.10, 0.92 +/- 0.06, 0.97 +/- 0.08, and 0.97 +/- 0.10, respectively. At both 1 hour and 1 day after surgery, rabbits treated with BSS-plus + O2 had an earlier b-wave return to baseline findings, but the differences were not statistically significant (P > 0.05). Mean dark-adapted b-wave amplitudes of operated eye/nonoperated eye ratios +/- SD for BSS and BSS + O2 before surgery and 1 hour, 1 day, 1 week, and 1 month after surgery were 1.02 +/- 0.10, 0.47 +/- 0.09, 0.77 +/- 0.07, 0.89 +/- 0.07, and 0.89 +/- 0.07 and 1.02 +/- 0.06, 0.62 +/- 0.16, 0.94 +/- 0.09, 0.97 +/- 0.08, and 0.96 +/- 0.06, respectively. One hour and 1 day after surgery, ERG readings for rabbits treated with BSS + O2 exhibited a statistically significantly earlier return of ERG voltage to baseline values compared with both BSS and BSS + L (P = 0.05 and P = 0.02, respectively). One day after surgery, rabbits treated with BSS alone had the lowest ERG ratios. One week and 1 month after surgery, for all solutions tested other than BSS, ERG values were within normal limits., Conclusion: The use of oxygenated solutions appears to affect ERG readings after pars plana vitrectomy. Further studies to evaluate the role of oxygenated solutions in different vitreoretinal surgical procedures are warranted.
- Published
- 2007
- Full Text
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21. A new model of experimental subretinal neovascularization in the rabbit.
- Author
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Qiu G, Stewart JM, Sadda S, Freda R, Lee S, Guven D, de Juan E Jr, and Varner SE
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- Animals, Biocompatible Materials administration & dosage, Choroid pathology, Collagen administration & dosage, Drug Combinations, Fluorescein Angiography methods, Injections, Laminin administration & dosage, Proteoglycans administration & dosage, Rabbits, Retina pathology, Retinal Vessels pathology, Tomography, Optical Coherence methods, Vascular Endothelial Growth Factor A administration & dosage, Choroidal Neovascularization pathology, Disease Models, Animal
- Abstract
Existing animal models of choroidal neovascularization (CNV) present several problems: they are hard to reproduce, they are inefficient, and the CNV created is not sustainable. The purpose of this study is to develop a highly efficient, reliable, sustainable rabbit model of CNV to facilitate the study of anti-angiogenic and anti-proliferative therapies for ocular diseases. Twenty-two pigmented rabbits were used in this study. Eleven rabbits received subretinal injections of either 10 microl of Matrigel with 500 ng of vascular endothelial growth factor (VEGF) or 20 microl of Matrigel with 750 ng of VEGF; eight rabbits received subretinal injections of either 10 or 20 microl of Matrigel only; three rabbits used as controls received subretinal injections of 20 microl phosphate-buffered saline (PBS) alone. Fundus photography, fluorescein angiography, optical coherence tomography, and histologic examinations were performed 1, 2, 4, and 9 weeks after injection. All experimental eyes showed angiographic leakage within this localized area 1 week after injection. The amount of leakage usually increased at weeks 2 and 4 and, in most cases, persisted at week 9. Control eyes demonstrated no leakage at any time point. Optical coherence tomography of treated eyes showed subretinal fluid and the presence of a lesion, possibly vascular or fibrotic, at the site of the leakage. Histologic analysis confirmed the presence of new subretinal blood vessels in the areas of Matrigel deposit. In conclusion, this novel method provides a highly reproducible, reliable, and sustainable rabbit model of experimental choroidal neovascularization. Such a model may prove useful for screening new anti-angiogenic therapies in a larger animal eye.
- Published
- 2006
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22. Rapid recurrence of geographic atrophy after full macular translocation for nonexudative age-related macular degeneration.
- Author
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Khurana RN, Fujii GY, Walsh AC, Humayun MS, de Juan E Jr, and Sadda SR
- Subjects
- Aged, Atrophy, Fluorescein Angiography, Humans, Male, Recurrence, Visual Acuity, Visual Field Tests, Macular Degeneration surgery, Pigment Epithelium of Eye pathology, Postoperative Complications, Retina pathology, Retina transplantation
- Abstract
Objective: To report the recurrence of geographic atrophy (GA) in a patient with nonexudative age-related macular degeneration (AMD) after full macular translocation., Design: Observational case report., Methods: Review of the clinical, photographic, and angiographic records of a patient with GA who underwent full macular translocation., Main Outcome Measures: Progression of GA., Results: A 73-year-old man with GA secondary to nonexudative AMD underwent a macular translocation with 360 peripheral retinectomy (MT 360) in his left eye. On postoperative month 4, fundus photography showed subtle alterations of the pigment underneath the translocated foveal region. On postoperative month 9, the visual acuity worsened to preoperative levels and there was frank retinal pigment epithelium atrophy involving the new macular region., Conclusions: The rapid recurrence and development of GA in the translocated fovea after MT 360 raise new questions regarding the pathogenesis of GA. They also raise concerns regarding the use of MT 360 in the management of nonexudative AMD.
- Published
- 2005
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23. Fabrication, implantation, elution, and retrieval of a steroid-loaded polycaprolactone subretinal implant.
- Author
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Beeley NR, Rossi JV, Mello-Filho PA, Mahmoud MI, Fujii GY, de Juan E Jr, and Varner SE
- Subjects
- Angiography methods, Animals, Aqueous Humor metabolism, Biocompatible Materials, Cell Proliferation, Choroid metabolism, Drug Delivery Systems, Drug Implants, Neovascularization, Pathologic, Polymers chemistry, Prostheses and Implants, Prosthesis Implantation, Rabbits, Retina pathology, Serum Albumin, Bovine chemistry, Steroids chemistry, Time Factors, Triamcinolone chemistry, Absorbable Implants, Polyesters chemistry, Polyesters pharmacology, Retina drug effects, Steroids administration & dosage
- Abstract
A subretinal drug delivery system was developed to overcome the limitations of current treatments for retinal disease. A rod-shaped implant was made by embedding the corticosteroid triamcinolone acetonide within a biodegradable polycaprolactone polymer matrix. The implant was fabricated by homogeneously mixing the polymer and drug in solvent. The mixture was then dried, melted, and extruded, and the prepared solid form was drawn into a filament. The rods were mechanically sectioned to a length of 2 mm with a diameter of up to 320 microm. The rods were successfully implanted into the subretinal space of six rabbits. No complications were observed during the 4-week follow-up period. Initial observations of the implantation and elution characteristics revealed that polycaprolactone is well tolerated by the retinal tissue and that the implant can elute steroid for a period of at least 4 weeks without eliciting inflammatory response or complications. In vitro drug elution rates of different polymer to drug ratios and geometries into a balanced salt solution/bovine serum albumin (1%) solution showed an early rapid-release phase and late first-order phase. Histology and device retrieval after implantation revealed minimal encapsulation and good preservation of cellular morphology during the follow-up period and a more fibrous polymer microstructure of the implant., ((c) 2005 Wiley Periodicals, Inc.)
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- 2005
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24. Outcomes of 140 consecutive cases of 25-gauge transconjunctival surgery for posterior segment disease.
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Lakhanpal RR, Humayun MS, de Juan E Jr, Lim JI, Chong LP, Chang TS, Javaheri M, Fujii GY, Barnes AC, and Alexandrou TJ
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- Aged, Conjunctiva surgery, Female, Humans, Intraocular Pressure, Male, Middle Aged, Minimally Invasive Surgical Procedures, Retrospective Studies, Safety, Treatment Outcome, Visual Acuity, Vitrectomy methods, Eye Diseases surgery, Retinal Diseases surgery, Vitrectomy instrumentation, Vitreous Body surgery
- Abstract
Purpose: To evaluate the safety and efficacy of 25-gauge instrumentation for a variety of vitreoretinal conditions on previously nonvitrectomized eyes., Design: Single-center, retrospective, interventional case series., Participants: One-hundred forty eyes of 140 patients were evaluated at the Doheny Retina Institute from July 2002 to July 2003., Intervention: All patients underwent surgical procedures using the Millennium 25-gauge Transconjunctival Standard Vitrectomy system. Twenty eyes (14.3%) underwent procedures without vitrectomy., Main Outcome Measures: Postoperative visual acuity (VA), intraocular pressure, surgical time, postoperative inflammation, complications, and number of sutured sites., Results: No intraoperative complications were noted. No cases required conversion to 20-gauge machines. Ten cases (7.1%) involved single-site sclerotomy suture placement due to bleb formation at the conclusion of the procedure, but 5 of these entry sites were enlarged to facilitate larger instrumentation for tissue manipulation. Median VA improved from 20/250 (logarithm of the minimum angle of resolution, 1.08+/-0.47) preoperatively to 20/60 (0.47+/-0.30) (P<0.0001) at final visit. Mean follow-up was 33.8+/-9.7 weeks, and all eyes were observed for a minimum of 12 weeks. Mean total surgical time was 17.4+/-6.9 minutes. Intraocular pressures remained stable throughout the postoperative course. Five eyes (3.8%) presented on day 1 with shallow choroidal detachments, but all resolved by day 7, and none required volume infusion during the postoperative period. All but one of these cases was within the first 50 procedures performed. No detectable inflammation was noted in any eyes by 4 weeks postoperatively. No case of retinal detachment or endophthalmitis was recorded., Conclusions: Transconjunctival surgery using 25-gauge instrumentation may hasten postoperative recovery by decreasing overall surgical time and postoperative inflammation. Procedures requiring minimal intraocular manipulation did not require sutures and, thus, may be better suited for this surgical modality.
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- 2005
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25. Photoreceptor differentiation and integration of retinal progenitor cells transplanted into transgenic rats.
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Qiu G, Seiler MJ, Mui C, Arai S, Aramant RB, de Juan E Jr, and Sadda S
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- Animals, Animals, Genetically Modified physiology, Cell Differentiation physiology, Cell Survival physiology, Cells, Cultured, Disease Models, Animal, Glial Fibrillary Acidic Protein analysis, Immunohistochemistry methods, Rats, Retinal Degeneration physiopathology, Rhodopsin analysis, Stem Cell Transplantation methods, Synapsins analysis, Tomography, Optical Coherence methods, Photoreceptor Cells physiopathology, Retina physiopathology, Stem Cells physiology
- Abstract
Previous studies evaluating neural stem cells transplanted into the mature retina have demonstrated limited levels of graft-host integration and photoreceptor differentiation. The purpose of this investigation is to enhance photoreceptor cell differentiation and integration of retinal progenitor cells (RPC) following subretinal transplantation into retinal degenerate rats by optimization of isolation, expansion, and transplantation procedures. RPCs were isolated from human placental alkaline phosphatase (hPAP)-positive embryonic day 17 (E17) rat retina and expanded in serum-free defined media. RPCs at passage 2 underwent in vitro induction with all trans retinoic acid or were transplanted into the subretinal space of post-natal day (P) 17 S334ter-3 and S334ter-5 transgenic rats. Animals were examined post-operatively by ophthalmoscopy and optical coherence tomography (OCT) at weeks 1 and 4. Differentiation profiles of RPCs, both in vitro and in vivo were analysed microscopically by immunohistochemistry for various retinal cell specific markers. Our results demonstrated that the majority of passage 2 RPCs differentiated into retina-specific neurons expressing rhodopsin after in vitro induction. Following subretinal transplantation, grafted cells formed a multi-layer cellular sheet in the subretinal space in both S334ter-3 and S334ter-5 rats. Prominent retina-specific neuronal differentiation was observed in both rat lines as evidenced by recoverin or rhodopsin staining in 80% of grafted cells. Less than 5% of the grafted cells expressed glial fibrillary acidic protein. Synapsin-1 (label for nerve terminals) positive neural processes were present at the graft-host interface. Expression profiles of the grafted RPCs were similar to those of RPCs induced to differentiate in vitro using all-trans retinoic acid. In contrast to our previous study, grafted RPCs can demonstrate extensive rhodopsin expression, organize into layers, and show some features of apparent integration with the host retina following subretinal transplantation in slow and fast retinal degenerate rats. The similarity of the in vitro and in vivo RPC differentiation profiles suggests that intrinsic signals may have a significant contribution to RPC cell fate determination.
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- 2005
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26. Transvitreal limited arteriovenous-crossing manipulation without vitrectomy for complicated branch retinal vein occlusion using 25-gauge instrumentation.
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Lakhanpal RR, Javaheri M, Ruiz-Garcia H, De Juan E Jr, and Humayun MS
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- Adult, Aged, Aged, 80 and over, Connective Tissue pathology, Female, Fluorescein Angiography, Humans, Macular Edema complications, Macular Edema diagnosis, Macular Edema surgery, Male, Middle Aged, Regional Blood Flow, Retinal Hemorrhage complications, Retinal Hemorrhage diagnosis, Retinal Hemorrhage surgery, Retinal Vein Occlusion diagnosis, Retinal Vein Occlusion etiology, Tomography, Optical Coherence, Visual Acuity, Vitrectomy, Connective Tissue surgery, Ophthalmologic Surgical Procedures instrumentation, Retinal Artery, Retinal Vein, Retinal Vein Occlusion surgery
- Abstract
Purpose: To evaluate a new technique, 25-gauge transvitreal limited arteriovenous-crossing manipulation without vitrectomy (LAM), for the treatment of branch retinal vein occlusion (BRVO) complicated by macular hemorrhage and/or macular edema recalcitrant to grid laser photocoagulation., Methods: Twelve eyes of 12 patients underwent LAM for BRVO performed by a single surgeon (M.S.H.) using the 25-gauge nitinol flexible-extendable blunt pick. The presence or absence of intraoperative reperfusion visualization, pre- and postoperative visual acuity, macular thickness as measured by optical coherence tomography, intraocular pressure, and lens status were evaluated., Results: Restoration of blood flow was noted in all patients and was based on intraoperative reestablishment of a red column of erythrocytes through the previously closed vessel. Mean visual acuity improved from 20/200 (logarithm of the minimal angle of resolution [LogMAR] +/- SD, 1.00 +/- 0.32) preoperatively to 20/70 (LogMAR +/- SD, 0.56 +/- 0.28) (P = 0.0003) at the final visit. Eleven (92%) of 12 eyes had >or=2 lines of visual improvement. Five eyes (45%) had final visual acuity of 20/50 or better. Mean macular thickness +/- SD improved from 401.0 +/- 73.2 to 178.7 +/- 19.6 microm (P < 0.0001) at the final visit. No statistically significant difference was noted in cataract progression or intraocular pressure. Mean follow-up +/- SD was 49.9 +/- 19.6 weeks. All patients were observed for at least 12 weeks., Conclusion: LAM may achieve outcomes comparable with those of arteriovenous adventitial sheathotomy for complicated BRVO.
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- 2005
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27. Retinal vein cannulation with prolonged infusion of tissue plasminogen activator (t-PA) for the treatment of experimental retinal vein occlusion in dogs.
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Tameesh MK, Lakhanpal RR, Fujii GY, Javaheri M, Shelley TH, D'Anna S, Barnes AC, Margalit E, Farah M, De Juan E Jr, and Humayun MS
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- Animals, Disease Models, Animal, Dogs, Feasibility Studies, Fluorescein Angiography, Infusions, Intravenous, Safety, Swine, Treatment Outcome, Catheterization, Peripheral methods, Fibrinolytic Agents administration & dosage, Retinal Vein drug effects, Retinal Vein Occlusion drug therapy, Tissue Plasminogen Activator administration & dosage
- Abstract
Purpose: To evaluate the feasibility, safety, and efficacy of local thrombolytic agents directly injected into occluded retinal veins in an experimental animal model., Design: Experimental animal study., Methods: This experimental study was performed in two phases. In phase 1, 15 enucleated porcine eyes and 8 in vivo canine eyes were used for the development of the instrumentation and surgical technique required for retinal vein cannulation with prolonged intravascular infusion. In phase 2 of this study, experimental branch retinal vein occlusion was photo-chemically created using an intravenous injection of rose bengal followed by diode laser photocoagulation in eight eyes of eight dogs. Four eyes were treated by retinal vein cannulation and an injection of tissue plasminogen activator (t-PA) using a specifically designed microcatheter, while the remaining four eyes were untreated (control group). The total amount of t-PA injected intravenously ranged from 400 to 1000 mug, infused over a period ranging from 25 to 45 minutes with a mean pressure of 40 psi, resulting in a mean injection flow rate of 0.05 ml/min. The dogs underwent clinical examination, fluorescein angiography, and histologic examination. Main outcome measures were: Achievement of prolonged intravascular infusion of t-PA, changes in fundus appearance, fluorescein angiography, and histology., Results: A microcatheter instrument and a surgical technique for retinal vein cannulation with prolonged intravascular infusion were developed. Cannulation and t-PA infusion for a period of at least 30 minutes was achieved in all four treated eyes with experimental branch retinal vein occlusion. No complications were recorded in all treated eyes. One week and 1 month postoperatively, treated eyes exhibited marked decreases in retinal hemorrhages, retinal vein dilation, and tortuosity, whereas nontreated eyes exhibited persistence of these findings. Fluorescein angiography demonstrated improved circulatory flow in treated relative to nontreated eyes. Histologic analysis confirmed the presence of thrombi in nontreated eyes only., Conclusions: Retinal vein cannulation with prolonged intravascular injection of t-PA is feasible and safe, and this may offer a new treatment option for retinal vein occlusion.
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- 2004
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28. Retinal thickness in normal and RCD1 dogs using optical coherence tomography.
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Panzan CQ, Güven D, Weiland JD, Lakhanpal RR, Javaheri M, de Juan E Jr, and Humayun MS
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- Animals, Diagnostic Techniques, Ophthalmological veterinary, Disease Models, Animal, Dogs, Nerve Fibers pathology, Retinal Degeneration diagnosis, Retinal Ganglion Cells pathology, Video Recording, Dog Diseases diagnosis, Retina pathology, Retinal Degeneration veterinary, Tomography, Optical Coherence veterinary
- Abstract
Background and Objective: To compare retinal thickness and retinal nerve fiber layer (RNFL) thickness values obtained by optical coherence tomography (OCT) in normal dogs and dogs with rod-cone dysplasia type 1 (RCD1)., Materials and Methods: Eight eyes of 6 normal hound-bred dogs and 12 eyes of 6 dogs with RCD1, 2 to 5 years of age, were examined using the Fast RNFL Thickness, Fast Macular Thickness, and line scan protocols of OCT., Results: Retinal thickness was significantly higher in the tapetal fundus than in the non-tapetal fundus, in both normal (P = .0036) and RCD1 (P < .0001) dogs. Superotemporal, superonasal, and inferior retinal thickness values were significantly higher in normal dogs (P < .0001). Area centralis thickness was 183.5 +/- 10.66 microm in normal dogs and 136.16 +/- 13.12 microm in RCD1 dogs (P < .0001). There was no difference in RNFL thickness between normal and RCD1 dogs (P > .05)., Conclusion: OCT scanning in dogs is considered to be a useful method of evaluation in future retinal studies in this animal model.
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- 2004
29. Macular translocation in patients with recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization.
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Ng EW, Fujii GY, Au Eong KG, Reynolds SM, Melia BM, Kouzis AC, Humayun MS, de Juan E Jr, and Pieramici DJ
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- Adult, Aged, Aged, 80 and over, Choroidal Neovascularization etiology, Female, Fovea Centralis pathology, Humans, Male, Middle Aged, Pilot Projects, Recurrence, Retrospective Studies, Treatment Outcome, Visual Acuity, Vitrectomy, Choroidal Neovascularization surgery, Fovea Centralis surgery, Laser Coagulation, Macula Lutea transplantation
- Abstract
Purpose: To report visual outcomes and to examine surgical factors affecting outcomes in patients undergoing macular translocation for recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization., Design: Retrospective, noncomparative, interventional case series., Participants: A consecutive series of 31 eyes of 29 patients who underwent macular translocation for recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization., Intervention: Inferior macular translocation with punctate retinotomy performed by a single surgeon., Outcome Measures: Surgical and visual outcomes at 3 and 6 months after surgery and complications data are reported. Associations between surgical factors and visual outcomes were analyzed statistically., Results: Effective translocation was achieved in 77.4% of eyes. At 6 months, 54% of eyes achieved visual acuity (VA) better than 20/100, and 46% of eyes gained the equivalent of > or =2 Early Treatment Diabetic Retinopathy Study lines of vision. No association between size of recurrent choroidal neovascularization and visual outcome was identified. Eyes with a larger scar size experienced lower VA at 3 and 6 months, but scar size was not associated with change in VA at 3 and 6 months. Subretinal dissection during surgery to detach the macula was required in 8 of 31 eyes and was associated with a significantly increased incidence of peripheral retinal breaks. However, there was no difference in either VA or change in VA in eyes with and without subretinal dissection. Retinal detachment (RD) occurred in 6 of 31 eyes. No significant difference in the RD rate was observed between groups with or without subretinal dissection (P = 0.30)., Conclusion: Our pilot data suggest that macular translocation can result in favorable surgical outcomes in patients with recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization. Use of subretinal dissection intraoperatively in these patients does not seem to affect visual outcome adversely, but may be associated with increased risk of peripheral retinal breaks.
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- 2004
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30. Comparison of electrical stimulation thresholds in normal and retinal degenerated mouse retina.
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Suzuki S, Humayun MS, Weiland JD, Chen SJ, Margalit E, Piyathaisere DV, and de Juan E Jr
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- Animals, Disease Models, Animal, Electric Stimulation, Male, Mice, Mice, Inbred C57BL, Mice, Mutant Strains, Microelectrodes, Photic Stimulation, Retina physiopathology, Sensory Thresholds physiology, Action Potentials physiology, Retinal Degeneration physiopathology, Retinal Ganglion Cells physiology
- Abstract
Purpose: To compare the threshold for electrically elicited action potentials of retinal ganglion cells in normal mouse retina and photoreceptor degenerated (rd) mouse retina., Methods: Microelectrode recordings were made from retinal ganglion cells of normal and rd mice. Mice with a genetically based retinal degeneration (rd mice) were grown to the age of 16 weeks, when light-evoked responses could no longer be recorded. A bare wire was placed in the vitreous to stimulate the retina with charge-balanced current pulses. The following pulse shapes were investigated: single, square biphasic pulse, single sine wave, and biphasic pulse trains., Results: Normal mice had significantly lower stimulus thresholds than rd mice for all pulse shapes. In normal and rd mice, short pulses were more efficient with respect to total charge used, but required a higher current. In normal mice, sine wave stimulation was significantly more efficient than a biphasic pulse of the same duration. No difference was noted between sine wave and square wave stimulation in rd mice. Pulse trains offered little benefit over single pulses., Conclusion: The amount of electrical charge required to elicit an action potential is dependent on the condition of the retina and the shape of the stimulus pulse used to deliver the charge., (Copyright Japanese Ophthalmological Society 2004)
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- 2004
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31. Limited macular translocation: a clinicopathologic case report.
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Albini TA, Rao NA, Li A, Craft CM, Fujii GY, and De Juan E Jr
- Subjects
- Aged, Arrestin metabolism, Biomarkers analysis, Cell Count, Choroid blood supply, Choroidal Neovascularization etiology, Choroidal Neovascularization pathology, Choroidal Neovascularization surgery, Fluorescein Angiography, Humans, Immunoenzyme Techniques, Macular Degeneration complications, Macular Degeneration pathology, Macular Degeneration surgery, Male, Photoreceptor Cells, Vertebrate metabolism, Bruch Membrane pathology, Macula Lutea pathology, Macula Lutea transplantation, Photoreceptor Cells, Vertebrate pathology, Pigment Epithelium of Eye pathology
- Abstract
Objective: To illustrate the histopathologic findings in a patient who underwent limited macular translocation., Design: Observational case report., Methods: The patient underwent limited macular translocation for subfoveal choroidal neovascularization resulting from age-related macular degeneration. Thirty-one months after surgery, the patient had died and both eyes were obtained at autopsy. Serial sections through both maculas were obtained. Immunohistochemistry of the foveas with C10C10 and hCAR/LUMIf antibodies for rods and cones, respectively, was performed., Main Outcome Measures: Histopathologic changes in the operated eye as compared with the fellow eye., Results: There was no morphologic difference in the subfoveal retinal pigment epithelium, Bruch's membrane, or choriocapillaris, but there was a decreased cone density in the translocated fovea as compared with the fellow eye., Conclusions: In this patient, the fovea was translocated without causing apparent change in the underlying retinal pigment epithelium, Bruch's membrane, or choriocapillaris. Although there may be some photoreceptor loss, the excellent visual recovery suggests that the retinal pigment epithelium underlying the translocated fovea is functionally adequate.
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- 2004
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32. Use of rotational sutures for limited retinal translocation: a new technique for superior limited macular translocation.
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Güven D, Panzan CQ, Humayun MS, and De Juan E Jr
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- Animals, Disease Models, Animal, Intraocular Pressure, Rabbits, Tissue Transplantation methods, Transplantation, Autologous, Vitrectomy, Choroidal Neovascularization surgery, Nylons, Retina transplantation, Suture Techniques, Sutures
- Abstract
Purpose: To report a modified surgical technique for retinal translocation in eyes with subfoveal choroidal neovascularization., Design: Experimental animal study., Methods: Nine pigmented rabbits were used consecutively to apply this technique. Placement of inferotemporal scleral imbrication sutures was followed by vitrectomy with posterior hyaloid separation. Balanced saline solution (BSS) was injected subretinally with a 30G needle or with a 39G hydrodissection cannula and viscous fluid injector to detach one retinal quadrant. Under low intraocular pressure, the imbrication sutures were tied, the sclerotomy sites were closed, and intravitreal air tamponade was injected. Rotation sutures were passed and the eye globe was rotated approximately 90 degrees counterclockwise. The rotation sutures were removed after 24 hours. Retinal photographs were taken and fundus examination was performed on postoperative days 1, 2 and 7. The animals were sacrificed after 7 to 10 days for postmortem macroscopic examination., Results: The entire procedure was performed in nine eyes of nine rabbits. In eight eyes, translocation could be seen on the first postoperative day after removal of the rotation sutures. The average amount of translocation was 667 microm (range: 500-800 microm) in a nasal to inferonasal direction. Vitreous hemorrhage occurred at the end of surgery in one eye due to hypotony. Iatrogenic small retinal breaks occurred in 2 eyes but did not prevent completion of the procedure. There was only a temporary hyperemia of the eyelids and conjunctiva., Conclusion: Limited retinal translocation using rotational sutures provided a predictable amount of translocation in the planned direction. This technique is expected to be useful for superior macular translocation in humans.
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- 2004
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33. Virtual vitreoretinal surgical simulator as a training tool.
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Rossi JV, Verma D, Fujii GY, Lakhanpal RR, Wu SL, Humayun MS, and De Juan E Jr
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- Adult, Clinical Competence, Equipment Design, Feasibility Studies, Female, General Surgery, Humans, Internship and Residency, Male, Students, Medical, Computer Simulation, Education, Medical methods, Educational Technology instrumentation, Retina surgery, User-Computer Interface, Vitreous Body surgery
- Abstract
Objective: To demonstrate the feasibility and potential applicability of a virtual reality simulator for vitreoretinal surgery as a training and/or assessment tool., Methods: The subjects of this study included medical students, ophthalmologic residents, and trained vitreoretinal surgeons. There were three study groups. Group I comprised 22 subjects who performed a navigation task. The time to complete the task was recorded. The relationship between the completion time, experience, and stereopsis was evaluated. Group II included 6 subjects who consecutively performed the navigation task to evaluate their learning curve. Group III included 16 subjects who performed the membrane peeling task. The number of retinal contacts and the completion time were recorded. The relationship between experience and stereopsis with the number of contacts and the completion time were evaluated., Results: The average completion time in Group I for students, residents, and trained surgeons was 121.6, 92.5, and 70.6 seconds. There was a significant difference between students and trained surgeons (P = 0.004). In Group II, there was a significant decrease in the completion time with training (P = 0.001). In Group III, the average completion time for students, residents, and trained surgeons was 197, 144, and 118.2 seconds; the respective number of retinal contacts was 14, 8, and 3. There was a significant difference between students and residents (P = 0.05) and between residents and trained surgeons (P = 0.003) for the average completion time in Group III. There was a significant difference between students and trained surgeons (P = 0.003) for the number of contacts per average time and between students and residents (P = 0.05). There was a significant inverse correlation between stereopsis vision score and completion time in Group I and number of contacts per average time (P = 0.0004 and P = 0.01, respectively)., Conclusions: This study demonstrates potential applications of a vitreoretinal surgical simulator as a training and skills assessment tool for novice, inexperienced, and trained surgeons. A simulator can be used to teach specific techniques and train surgeons.
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- 2004
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34. Effects of indocyanine green injection on the retinal surface and into the subretinal space in rabbits.
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Maia M, Kellner L, de Juan E Jr, Smith R, Farah ME, Margalit E, Lakhanpal RR, Grebe L, Au Eong KG, and Humayun MS
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- Animals, Fluorescein Angiography, Injections, Neuroglia drug effects, Neuroglia ultrastructure, Photoreceptor Cells, Vertebrate drug effects, Photoreceptor Cells, Vertebrate ultrastructure, Pigment Epithelium of Eye drug effects, Pigment Epithelium of Eye ultrastructure, Rabbits, Retina ultrastructure, Vitrectomy, Coloring Agents toxicity, Extracellular Space drug effects, Indocyanine Green toxicity, Retina drug effects
- Abstract
Purpose: To evaluate the effects of indocyanine green (ICG) injection on the retinal surface and into the subretinal space of rabbit eyes., Methods: Twenty-two Dutch-belted rabbits underwent two-port vitrectomy followed by injection of ICG (5 mg/mL) on the retinal surface and into the subretinal space. Balanced salt solution (BSS) was also injected subretinally. The locations where ICG was delivered (both epiretinal and subretinal) were exposed to light from an endoilluminator for 7 minutes. The animals were examined at 1, 7, and 14 days after surgery. The eyes were studied by fluorescein angiography as well as light and electron microscopy., Results: No damage was observed after epiretinal ICG injection, but subretinal ICG injection resulted in damage to the outer nuclear layer, photoreceptor inner and outer segments, and retinal pigment epithelium. This damage was more severe with longer follow-up. Control experiments without ICG, in which balanced salt solution was injected into the subretinal space or light was delivered on the epiretinal surface, demonstrated only damage to the photoreceptor outer segments., Conclusion: Subretinal delivery of ICG (5 mg/mL) in rabbits induces retinal pigment epithelium, photoreceptor inner and outer segment, and outer nuclear layer damage. These mechanisms of damage may explain the retinal pigment epithelium changes that are sometimes seen after ICG-assisted internal limiting membrane peeling in humans.
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- 2004
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35. Retinal pigment epithelial abnormalities after internal limiting membrane peeling guided by indocyanine green staining.
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Maia M, Haller JA, Pieramici DJ, Margalit E, de Juan E Jr, Farah ME, Lakhanpal RR, Au Eong KG, Guven D, and Humayun MS
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Basement Membrane surgery, Child, Epiretinal Membrane diagnosis, Female, Fluorescein Angiography, Humans, Male, Middle Aged, Pigment Epithelium of Eye pathology, Retinal Diseases diagnosis, Retinal Perforations diagnosis, Retrospective Studies, Coloring Agents adverse effects, Epiretinal Membrane surgery, Indocyanine Green adverse effects, Pigment Epithelium of Eye drug effects, Retinal Diseases chemically induced, Retinal Perforations surgery
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- 2004
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36. Effects of intravitreal indocyanine green injection in rabbits.
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Maia M, Margalit E, Lakhanpal R, Tso MO, Grebe R, Torres G, Au Eong KG, Farah ME, Fujii GY, Weiland J, de Juan E Jr, D'Anna SA, and Humayun MS
- Subjects
- Animals, Coloring Agents administration & dosage, Dose-Response Relationship, Drug, Electroretinography drug effects, Fluorescein Angiography, Indocyanine Green administration & dosage, Injections, Microscopy, Ophthalmoscopy, Rabbits, Retina physiopathology, Retina ultrastructure, Vitreous Body, Coloring Agents toxicity, Indocyanine Green toxicity, Retina drug effects
- Abstract
Purpose: To report the clinical, electrophysiologic, and histologic findings of different concentrations of indocyanine green (ICG) injected into the vitreous cavity of rabbit eyes., Methods: Forty-two rabbits underwent intravitreal injection of 0.1 mL of ICG in three different concentrations: 0.5 mg/mL (250 mOsm), 5 mg/mL (270 mOsm), and 25 mg/mL (170 mOsm). Fellow eyes were injected with 0.1 mL of balanced salt solution. Biomicroscopy, ophthalmoscopy, electroretinography, fluorescein angiography, and histologic evaluation were performed., Results: Eyes injected with 0.5 mg/mL of ICG showed b-wave latency delay on the first day after injection. Eyes injected with 5 mg/mL of ICG showed b-wave latency delay and decreased b-wave amplitude on the first and seventh days after injection; delayed a-wave latency on the first day after injection was also observed. Eyes injected with 25 mg/mL of ICG showed b- and a-wave amplitude and latency abnormalities during the entire follow-up. Direct correlation of increasing retinal edema proportional to the progressively increasing ICG concentrations was shown on histologic evaluation., Conclusion: Intravitreal ICG injection in rabbit eyes may impair retinal function and morphology proportional to the progressively increasing ICG dosages.
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- 2004
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37. Visual task performance in blind humans with retinal prosthetic implants.
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Weiland JD, Yanai D, Mahadevappa M, Williamson R, Mech BV, Fujii GY, Little J, Greenberg RJ, de Juan E Jr, and Humayun MS
- Abstract
A prototype electronic retinal prosthesis has been tested in three subjects. The system features an implanted retinal stimulator and an external system for image acquisition, processing, and telemetry. The subjects in general performed better than chance on psychophysical tests involving object detection, object counting, object discrimination, and direction of movement.
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- 2004
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38. Characteristics of visual loss by scanning laser ophthalmoscope microperimetry in eyes with subfoveal choroidal neovascularization secondary to age-related macular degeneration.
- Author
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Fujii GY, De Juan E Jr, Humayun MS, Sunness JS, Chang TS, and Rossi JV
- Subjects
- Aged, Aged, 80 and over, Cross-Sectional Studies, Female, Fixation, Ocular physiology, Fluorescein Angiography, Fovea Centralis, Humans, Male, Middle Aged, Ophthalmoscopes, Retrospective Studies, Vision Disorders etiology, Vision Disorders physiopathology, Visual Acuity, Visual Fields, Choroidal Neovascularization etiology, Macular Degeneration complications, Retina pathology, Vision Disorders diagnosis, Visual Field Tests methods
- Abstract
Purpose: To evaluate the effects of subfoveal choroidal neovascularization secondary to age-related macular degeneration on functional parameters obtained by scanning laser ophthalmoscope microperimetry., Design: Retrospective observational case series and cross-sectional study., Methods: At the Doheny Retina Institute and Wilmer Eye Institute a consecutive series of 179 eyes of 175 patients with subfoveal choroidal neovascularization secondary to age-related macular degeneration was studied. The onset of visual symptoms, best-corrected visual acuity, fluorescein angiography, evaluation of fundus microperimetry and fixation pattern using the Rodenstock scanning laser ophthalmoscope were obtained for each patient. The main outcome measures were central retinal sensitivity and fixation pattern (fixation location and fixation stability) in eyes with subfoveal choroidal neovascularization and their relationship to the length of disease, type and characteristics of choroidal neovascularization, and visual acuity., Results: Of 179 eyes, 135 (75%) had central fixation, 27 (15%) had poor central fixation, and 17 (9%) had predominantly eccentric fixation. Seventy-six eyes (42%) had stable fixation, 70 eyes (39%) had relatively unstable fixation, and 33 eyes (18%) had unstable fixation. In 50 eyes (28%) a dense central scotoma was noted. Eighty-nine of 100 eyes (89%) with length of symptoms of less than 3 months had predominantly central fixation and 58 (58%) had stable fixation; 14 of 34 eyes (41%) with length of symptoms of more than 6 months had predominantly central fixation, and 5 eyes (15%) had stable fixation. In 15 eyes of patients who elected not to receive treatment, successive scanning laser ophthalmoscope microperimetry were obtained over time (follow-up of 18 months after onset of symptoms). Three months or less after the onset of symptoms, 13 eyes (87.7%) had predominantly central fixation and 9 eyes (60%) had stable fixation. More than 3 months and 6 months or less after the onset of symptoms, 10 eyes (66.7%) had predominantly central fixation and 7 eyes (46.7%) had stable fixation. This trend was further demonstrated in eyes more than 6 months after the onset of symptoms., Conclusions: We conclude that the sequence of events leading to visual function deterioration appears to involve an initial mild decrease in central retinal sensitivity and visual acuity followed by progressive fixation instability and, ultimately, development of an absolute central scotoma with totally eccentric fixation. Increased length of disease is associated with worse fixation pattern and retinal sensitivity deterioration as assessed by scanning laser ophthalmoscope microperimetry. A better understanding of the characteristics of visual loss assessed by fixation pattern evaluation and microperimetry in age-related macular degeneration may help optimize timing, patient selection, and treatment options in eyes with this condition.
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- 2003
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39. Advances in the development of visual prostheses.
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Lakhanpal RR, Yanai D, Weiland JD, Fujii GY, Caffey S, Greenberg RJ, de Juan E Jr, and Humayun MS
- Subjects
- Humans, Prosthesis Design, Electric Stimulation instrumentation, Photic Stimulation instrumentation, Prostheses and Implants, Vision Disorders rehabilitation
- Abstract
Visual prostheses are based on neuronal electrical stimulation at different locations along the visual pathway (ie, cortical, optic nerve, epiretinal, subretinal). In terms of retinal prostheses, advances in microtechnology have allowed for the development of sophisticated, high-density integrated circuit devices that may be implanted either in the subretinal or epiretinal space. Analogous to the cochlear implants for some forms of deafness, these devices could restore useful vision by converting visual information into patterns of electrical stimulation that would excite the remaining spared inner retinal neurons in patients with diseases such as retinitis pigmentosa and age-related macular degeneration. The different types of implants and recent results are discussed, but special emphasis is given to retinal implants.
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- 2003
- Full Text
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40. Visual and electrical evoked response recorded from subdural electrodes implanted above the visual cortex in normal dogs under two methods of anesthesia.
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Margalit E, Weiland JD, Clatterbuck RE, Fujii GY, Maia M, Tameesh M, Torres G, D'Anna SA, Desai S, Piyathaisere DV, Olivi A, de Juan E Jr, and Humayun MS
- Subjects
- Animals, Dogs, Electric Stimulation methods, Electrodes, Implanted, Evoked Potentials, Visual drug effects, Halothane pharmacology, Propofol pharmacology, Visual Cortex drug effects, Anesthesia methods, Anesthetics, Inhalation pharmacology, Anesthetics, Intravenous pharmacology, Evoked Potentials, Visual physiology, Visual Cortex physiology
- Abstract
Sensitive methods are required to record electrical evoked potentials over the visual cortex to evaluate the efficacy and safety of a retinal prosthesis before it can be implanted on the retinal surface of patients afflicted by outer retinal diseases. This study was designed to examine subdural electrodes as a mean to evaluate cortical evoked potentials in response to light and electrical stimulation of the retina in three dogs under two methods of anesthesia-halothane and propofol. Results showed that subdural electrodes could be stabilized over the visual cortex for several (3-5) months, and that they were 6.95 times more sensitive than subdermal electrodes in recording cortical visual evoked potentials (VEPs) and 4.31 times more sensitive in recording cortical electrical evoked potentials under both methods of anesthesia. The waveforms' shape changed for each electrode in the subdural array during 6/6 (100%) and 20/38 (52%) multi-channel recording sessions under halothane and propofol, respectively. This change could point to a cortical retinotopic organization versus hierarchical organization of different cortical areas for a given retinal stimulus. In summary, subdural electrodes show promising results for recording visual and electrical evoked responses (EERs) and thus for evaluation of the retinal prosthesis.
- Published
- 2003
- Full Text
- View/download PDF
41. Combined phacoemulsification, intraocular lens implantation, and vitrectomy for eyes with coexisting cataract and vitreoretinal pathology.
- Author
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Demetriades AM, Gottsch JD, Thomsen R, Azab A, Stark WJ, Campochiaro PA, de Juan E Jr, and Haller JA
- Subjects
- Adult, Aged, Aged, 80 and over, Eye Diseases surgery, Female, Humans, Lenses, Intraocular, Male, Middle Aged, Retinal Diseases surgery, Retrospective Studies, Treatment Outcome, Visual Acuity, Vitreous Body surgery, Cataract complications, Eye Diseases complications, Lens Implantation, Intraocular methods, Phacoemulsification methods, Retinal Diseases complications, Vitrectomy methods, Vitreous Body pathology
- Abstract
Purpose: To report the preoperative, intraoperative, and postoperative outcomes of combining phacoemulsification and posterior chamber intraocular lens (IOL) implantation with pars plana vitrectomy in eyes with significant cataract and coexisting vitreoretinal pathology., Design: Retrospective, consecutive, interventional case series., Methods: Charts of patients undergoing combined procedures at the Wilmer Ophthalmologic Institute between March 1995 and May 2000 were reviewed., Results: In all, 122 eyes of 111 patients were identified. Patient ages ranged from 27 to 89 years (mean 65). Forty-three eyes had diabetic retinopathy; 11 had undergone vitrectomy previously. Macular pathology (hole, membrane, choridal neovascularization) was present in 69 eyes. The most common indications for surgery were diabetic vitreous hemorrhage, macular hole, epiretinal membrane, and retinal detachment. In all cases, phacoemulsification and IOL implantation were performed before vitreoretinal surgery. Preoperative vision ranged from 20/30 to light perception and postoperative vision ranged from 20/20 to no light perception. In 105 patients vision improved, in 7 there was no change, and in 10 vision decreased. Postoperative complications included opacification of the posterior capsule, increased intraocular pressure, corneal epithelial defects, vitreous hemorrhage, retinal detachment and iris capture by the IOL., Conclusions: Combined surgery is a reasonable alternative in selected patients. Techniques that may simplify surgery and reduce complications include: careful, limited, curvilinear capsulorhexis; in-the-bag placement of IOLs; use of IOLs with larger optics; suturing of cataract wounds before vitrectomy; use of miotics and avoidance of long-acting dilating drops in patients with intravitreal gas; and use of wide-field viewing systems., (Copyright 2003 by Elsevier Science Inc.)
- Published
- 2003
- Full Text
- View/download PDF
42. Heat effects on the retina.
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Piyathaisere DV, Margalit E, Chen SJ, Shyu JS, D'Anna SA, Weiland JD, Grebe RR, Grebe L, Fujii G, Kim SY, Greenberg RJ, De Juan E Jr, and Humayun MS
- Subjects
- Animals, Body Temperature, Dogs, Electroretinography, Fundus Oculi, Hot Temperature, Models, Animal, Radiation Injuries, Experimental physiopathology, Retina physiology, Retinal Diseases physiopathology, Thermography, Hyperthermia, Induced adverse effects, Radiation Injuries, Experimental etiology, Retina radiation effects, Retinal Diseases etiology
- Abstract
Background and Objective: To study the heat and power dissipation effect of anintraocular electronic heater on the retina. The determination of thermal parameters that are nonharmful to the retina will aid in the development of an implantable intraocular electronic retinal prosthesis., Materials and Methods: In dogs, five different retinal areas were touched with a custom intraocular heater probe (1.4 x 1.4 x 1.0 mm) for 1 second while the heater dissipated 0 (control), 10, 20, 50, or 100 mW. In a second protocol, the heater was mechanically held in the vitreous cavity while dissipating 500 mW for 2 hours while monitoring intraocular temperature. The animals were observed for 4 weeks with serial fundus photography and electroretinography. The procedure was then repeated in the fellow eye. The dogs were killed and both eyes were enucleated and submitted for histology., Results: In experiments using protocol 1, heater settings of 50 mW or higher caused an immediate visible whitening of the retinal tissue. Histologically, this damage was evident only if the eyeswere immediately enucleated. Permanent damage was caused by heater settings of 100 mW or higher. Under protocol 2, no ophthalmologic, electroretinography, or histologic differences were noted between the groups. Temperature increases of 5 degrees C in the vitreous and 2 degrees C near the retina were noted., Conclusions: The liquid environment of the eye acts as a heat sink that is capable of dissipating a significant amount of power. An electronic chip positioned away from the retina can run at considerably higher powers than a chip positioned on the retinal surface.
- Published
- 2003
43. Autologous transplantation of retinal pigment epithelium after mechanical debridement of Bruch's membrane.
- Author
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Phillips SJ, Sadda SR, Tso MO, Humayan MS, de Juan E Jr, and Binder S
- Subjects
- Animals, Atrophy, Bruch Membrane ultrastructure, Capillaries, Cell Differentiation, Cell Division, Cell Survival, Cell Transplantation, Choroid blood supply, Choroid ultrastructure, Debridement, Fluorescein Angiography, Photoreceptor Cells, Vertebrate ultrastructure, Pigment Epithelium of Eye ultrastructure, Rabbits, Transplantation, Autologous, Bruch Membrane surgery, Pigment Epithelium of Eye transplantation
- Abstract
Purpose: To determine whether transplantation of autologous retinal pigment epithelium (RPE) will prevent atrophy of the choriocapillaris and loss of photoreceptors in an area in which the RPE has been mechanically debrided from Bruch's membrane., Methods: Abrasive debridement of RPE was performed with a metal cannula after localized retinal bleb detachments in two separate areas of the rabbit retina. The RPE cell suspension aspirated from one of the debridement sites was transplanted to the other. The debridement-only site served as control. The transplant and control sites were evaluated after 30 days by color fundus photography, fluorescein angiography, light microscopy and transmission electron microscopy., Results: Compared with debridement only, debridement plus transplantation of RPE resulted in more complete repopulation of the bare Bruch's membrane surface with relative preservation of choriocapillaris and photoreceptors., Conclusion: Autologous transplantation of RPE onto an abrasively debrided Bruch's membrane decreases choriocapillaris atrophy and photoreceptor loss.
- Published
- 2003
- Full Text
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44. Force comparison of air currents produced by a standard and modified infusion cannula.
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Ladd BS, Fujii GY, Gupta P, Jensen PS, Kouzis A, Rossi JV, Barnes A, and De Juan E Jr
- Subjects
- Biomechanical Phenomena, Humans, Intraoperative Complications prevention & control, Models, Biological, Pressure, Catheterization instrumentation, Ophthalmologic Surgical Procedures instrumentation
- Abstract
Objective: To develop and characterize an infusion cannula that reduces the intraocular jet forces created during fluid-air exchange., Methods: A new infusion cannula was manufactured by adding a baffle 1.0 mm perpendicular to the distal opening of a 20-gauge infusion. The forces generated by the modified and standard cannulas were measured at a constant air infusion pressure of 50 mmHg by using a force sensor coupled to a schematic eye with eight radial positions from 0 degrees to 180 degrees along the circumference. Five different orientations relative to the baffle support of the modified cannula were evaluated at each position to assess the turbulent flow., Results: The standard cannula produced a maximum force of 0.14 mmHg at 180 degrees from the sensor. The modified cannula generated a maximum pressure of 0.017 mmHg at 67.5 degrees from the sensor. Overall, the force from the modified cannula was an order of magnitude less than the standard infusion cannula (P < 0.01)., Conclusions: The modifications of the new infusion cannula are passive with respect to its surgical performance. However, the additional baffle transforms laminar air currents into turbulent ones and allows dispersion of the jet forces, which should reduce barotrauma and desiccation of the retina during fluid-air exchange.
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- 2003
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45. Intraoperative ketorolac and eye pain after viteoretinal surgery: a prospective, randomized, placebo-controlled study.
- Author
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Fekrat S, Marsh MJ, Elsing SH, Raja SC, de Juan E Jr, Campochiaro PA, and Haller JA
- Subjects
- Aged, Analgesics, Non-Narcotic administration & dosage, Cyclooxygenase Inhibitors administration & dosage, Double-Blind Method, Eye Diseases surgery, Female, Humans, Injections, Intravenous, Intraoperative Care methods, Ketorolac Tromethamine administration & dosage, Male, Middle Aged, Nausea drug therapy, Pain Measurement, Prospective Studies, Retinal Diseases surgery, Vitreous Body surgery, Analgesics, Non-Narcotic therapeutic use, Cyclooxygenase Inhibitors therapeutic use, Ketorolac Tromethamine therapeutic use, Pain, Postoperative drug therapy, Scleral Buckling adverse effects, Vitrectomy adverse effects
- Abstract
Purpose: To compare the efficacy of one intraoperative dose of intravenous ketorolac tromethamine to saline placebo in controlling postoperative eye pain, nausea, and sedation following vitreoretinal surgery., Study Design: Prospective, randomized, placebo-controlled clinical trial., Methods: One hundred fourteen vitreoretinal surgical patients were randomized over a 7-month period to a single intraoperative intravenous dose of ketorolac tromethamine or placebo. All patients underwent surgery with intravenous sedation and retrobulbar anesthetic injection and had access to a standard postoperative analgesic regimen. After 2 and 5 hours, eye pain, nausea, and sedation levels were recorded using a standard visual analog scale. Analgesic requirements were tabulated., Results: Patients given ketorolac were significantly less likely to have postoperative eye pain than were placebo-treated patients (P = 0.0043). Fewer ketorolac patients required postoperative analgesia than placebo patients did (P < 0.0001). Four ketorolac patients (7%) required a narcotic compared to 11 placebo patients (20%) (P < 0.0001). Fewer ketorolac patients experienced nausea and sedation than placebo patients did, but this difference was not statistically significant., Conclusion: Ketorolac tromethamine is an effective nonnarcotic choice for postoperative pain control following vitreoretinal surgery. Pain control is particularly important in this group of patients, whose compliance with postoperative procedures and positioning may significantly affect surgical outcome.
- Published
- 2003
- Full Text
- View/download PDF
46. Limited macular translocation for the management of subfoveal choroidal neovascularization after photodynamic therapy.
- Author
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Fujii GY, de Juan E Jr, Humayun MS, and Chang TS
- Subjects
- Aged, Choroidal Neovascularization drug therapy, Choroidal Neovascularization etiology, Female, Fluorescein Angiography, Humans, Macular Degeneration complications, Male, Photosensitizing Agents therapeutic use, Porphyrins therapeutic use, Retrospective Studies, Verteporfin, Visual Acuity, Choroidal Neovascularization surgery, Macula Lutea transplantation, Photochemotherapy
- Abstract
Purpose: To report our initial experience of limited macular translocation in patients with subfoveal choroidal neovascularization secondary to age-related macular degeneration following photodynamic therapy with verteporfin., Design: Interventional case series., Methods: Retrospective review of four eyes of four consecutive patients with subfoveal choroidal neovascularization secondary to age-related macular degeneration who underwent effective limited macular translocation following photodynamic therapy. The mean logarithm of minimal angle of resolution preoperative best-corrected visual acuity was 20/190 (range, 20/150 to 20/200), and in all eyes the visual acuity was 20/150 or worse. The major outcome measures were postoperative visual acuity and complications related to the surgery., Results: The mean postoperative follow-up was 6.75 months (range, 6-8 months). Postoperative best-corrected visual acuity improved by 2 or more Snellen lines of visual acuity in three of four eyes (75%) and remained within 1 line in one of four eyes (25%). The mean postoperative best-corrected visual acuity was 20/100 (range, 20/40 to 20/150), and in two of the four eyes (50%) the visual acuity achieved was 20/100 or better. No complication was observed., Conclusions: Limited macular translocation may be a viable option in patients who have previously undergone photodynamic therapy.
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- 2003
- Full Text
- View/download PDF
47. Improvements after sheathotomy for branch retinal vein occlusion documented by optical coherence tomography and scanning laser ophthalmoscope.
- Author
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Fujii GY, de Juan E Jr, and Humayun MS
- Subjects
- Diagnostic Techniques, Ophthalmological, Fluorescein Angiography, Humans, Interferometry, Lasers, Light, Male, Middle Aged, Ophthalmoscopy, Retinal Vein Occlusion physiopathology, Tomography methods, Treatment Outcome, Visual Acuity, Decompression, Surgical methods, Retinal Vein Occlusion surgery, Vitrectomy methods
- Abstract
A 55-year-old man presented with decreased visual acuity of 20/400 and central foveal thickness of 450 microm as measured using optical coherence tomography due to a superior temporal branch retinal vein occlusion. Adventitial sheathotomy was performed with a 25-gauge sutureless transconjunctival vitrectomy system. At 1 day, 1 month, and 6 months postoperatively, visual acuity improved to 20/80, 20/40, and 20/30 OS, respectively; central foveal thickness decreased to 228, 195, and 161 microm, respectively; and the scanning laser ophthalmoscope microperimetry showed improved retinal sensitivity and fixation pattern with more stable and central fixation at both postoperative visits. This case indicates optical coherence tomography can detect an early positive effect of sheathotomy surgery on macular edema, and scanning laser ophthalmoscope can document associated improvement in fixation stability.
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- 2003
48. The value of preoperative tests in the selection of blind patients for a permanent microelectronic implant.
- Author
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Yanai D, Lakhanpal RR, Weiland JD, Mahadevappa M, Van Boemel G, Fujii GY, Greenberg R, Caffey S, de Juan E Jr, and Humayun MS
- Subjects
- Electroretinography, Evoked Potentials, Humans, Psychophysics methods, Blindness surgery, Microelectrodes, Patient Selection, Preoperative Care, Prostheses and Implants
- Abstract
Purpose: To determine the best candidates (ie, those requiring lowest current levels delivered to the retina to elicit visual perceptions) for long-term implantation of a microelectronic retinal implant through a series of preoperative visual, psychophysical, and electrophysiological tests., Methods: This study protocol was granted an investigational device exemption by the Food and Drug Administration and was approved by the institutional review board at the University of Southern California. After informed consent was obtained, all subjects underwent the following preoperative tests: dark-adapted bright flash and 30-Hz flicker electroretinograms, electrical evoked responses (EERs) using a Burian-Allen corneal electrode to stimulate the globe, and psychophysical tests to evaluate the light and electrically elicited visual perceptions. Intraocular stimulation (IOS) of the retina was performed by an array of electrodes positioned on the internal limiting lamina., Results: Lower vision correlated with less sensitive psychophysical responses (P<.0001). Lower vision and less sensitive psychophysical tests correlated with higher EER values for stimulus pulse widths of 2 ms (P<.0008) and 4 ms (P<.0002). Lower IOS currents correlated with more sensitive psychophysical responses (P<.02) and lower EER values at 4 ms (P<.04)., Conclusions: Preoperative testing, especially psychophysical and electrophysiological tests to assess light and electrically driven visual responses, can help in evaluating patients for suitability for receiving a permanent microelectronic retinal implant. Further study is warranted.
- Published
- 2003
49. Limited macular translocation: current concepts.
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Fujii GY, Au Eong KG, Humayun MS, and de Juan E Jr
- Subjects
- Choroidal Neovascularization etiology, Clinical Trials as Topic, Fluorescein Angiography, Humans, Macular Degeneration complications, Ophthalmologic Surgical Procedures, Choroidal Neovascularization surgery, Macula Lutea transplantation, Macular Degeneration surgery
- Abstract
Macular translocation is a promising treatment modality that offers patients a chance to improve their vision, potentially to a level that may allow reading and driving. Proper patient selection avoids surgery in eyes with permanently damaged central retina and identifies eyes with the greatest potential for good visual outcomes. Functionally, those patients with recent-onset subfoveal CNV without permanent foveal neurosensory retina damage have the greatest likelihood of good visual outcome. Use of fixation evaluation by means of the SLO appears to greatly optimize patient selection. Anatomically, the best candidates have small minimum desired translocations and healthy RPE-Bruch membrane-choriocapillaris complex beyond the borders of the lesion. The exact role of limited macular translocation for the management of subfoveal CNV in this era of photodynamic therapy remains to be evaluated, and a pilot multicenter, randomized, clinical trial is under way to compare the efficacy of limited macular translocation with photodynamic therapy in eyes with subfoveal CNV secondary to AMD.
- Published
- 2002
- Full Text
- View/download PDF
50. Iatrogenic choroidal neovascularization occurring in patients undergoing macular surgery.
- Author
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Ng EW, Bressler NM, Boyer DS, and de Juan E Jr
- Subjects
- Aged, Aged, 80 and over, Choroidal Neovascularization pathology, Choroidal Neovascularization surgery, Epiretinal Membrane surgery, Fluorescein Angiography, Humans, Iatrogenic Disease, Laser Coagulation, Macula Lutea transplantation, Male, Retrospective Studies, Bruch Membrane surgery, Choroidal Neovascularization etiology, Ophthalmologic Surgical Procedures adverse effects
- Abstract
Purpose: To report three cases of choroidal neovascularization (CNV) that occurred following surgical disruption of Bruch membrane during macular surgery., Methods: A retrospective case series was compiled. Macular translocation surgery with punctate retinotomy was performed in two patients for subfoveal CNV, and pars plana vitrectomy with epiretinal membrane (ERM) peeling was performed in one patient for idiopathic ERM., Results: CNV developed at a site of subretinal cannulation in two cases of macular translocation, and at a site of inadvertent injury to Bruch membrane with a vitreoretinal pick in the one case that underwent ERM peeling., Conclusions: These cases underscore the need to monitor breaks in Bruch membrane for CNV following macular surgery.
- Published
- 2002
- Full Text
- View/download PDF
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