1/214. Posterior lamellar keratoplasty for a case of pseudophakic bullous keratopathy.PURPOSE: To describe a new surgical technique for posterior corneal transplantation. methods: An elderly patient had painful, pseudophakic bullous keratopathy with low visual potential. Through a 9.0-mm scleral tunnel incision, a midstromal pocket was dissected across the cornea, and a posterior lamellar disk 7.0-mm in diameter, which consisted of posterior stroma, descemet membrane, and endothelium, was excised. A similarly shaped donor posterior disk was implanted in the recipient opening without suture fixation, and the scleral incision was sutured. RESULTS: Throughout the postoperative period, the posterior corneal transplant remained clear and in position. Three months after surgery, the "suture-in" astigmatic error was 3.5 diopters. Pachymetry measured 0.44 mm. CONCLUSION: Posterior lamellar keratoplasty may be a new surgical approach with which to manage corneal endothelial disorders.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
2/214. Pseudocapsulorrhexis in a patient with iridocorneal endothelial syndrome.We describe a patient with Chandler's syndrome variant of the iridocorneal endothelial syndrome in whom ectopic Descemet's membrane was found intraoperatively on the anterior surface of the lens. Initially, the membrane was confused with the anterior lens capsule during extracapsular cataract extraction, leading to the performance of a pseudocapsulorrhexis. Electron microscopy disclosed that the epilenticular membrane was composed of multiple layers of abnormal basement membrane consistent with the iridocorneal endothelial syndrome.- - - - - - - - - - ranking = 4keywords = membrane (Clic here for more details about this article) |
3/214. Peripheral lamellar keratoplasty for corneoscleral cyst: three case reports.PURPOSE: To examine whether peripheral lamellar keratoplasty (LKP) using preserved cornea was effective for the treatment of corneoscleral cysts. methods: Three patients with corneoscleral cysts underwent peripheral lamellar keratoplasty. Two patients had no history of trauma or ocular surgery and were considered to have congenital cysts. The other patient had a history of strabismus surgery that had been performed 7 years previously. The anterior wall of the cysts was removed by trephination, and the epithelial membrane lining the posterior wall was peeled off. Lamellar corneal buttons obtained from preserved corneas then were put in place and secured with 8-10 interrupted sutures. In one case, because the cyst was large and extended to the pupillary axis, peripheral LKP was performed for removal of the scleral and peripheral corneal cyst, and the inner wall of the central corneal cyst was removed with vigorous irrigation and a spatula. RESULTS: Histologic examination showed that all of the cysts were lined with nonkeratinizing epithelial cells. In all three cases, cysts have not reformed after a 1-5-year follow-up. CONCLUSIONS: The cysts were lined in epithelial cells, and removal of these epithelial cells was considered to be important for the prevention of recurrence. Peripheral LKP is effective for the treatment of corneoscleral cysts, since this procedure removes displaced epithelial cells and reconstructs the thin part of the cornea and sclera.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
4/214. Long-term outcome of aqueous shunt surgery in ten patients with iridocorneal endothelial syndrome.PURPOSE: To report the long-term outcome of ten patients with iridocorneal endothelial (ice) syndrome who underwent aqueous shunt surgery for uncontrolled glaucoma. DESIGN: Noncomparative, retrospective case series. PARTICIPANTS: The authors reviewed charts of ten patients with ice syndrome-related glaucoma who underwent aqueous shunt surgery at one institution between 1987 and 1996. MAIN OUTCOME MEASURES: intraocular pressure (IOP), number of glaucoma medications, and further surgical interventions were measured. RESULTS: With a median follow-up of 55 months, four eyes had adequate IOP control (IOP <21 mm Hg) with one or two medications after the initial aqueous shunt surgery. An additional three eyes achieved adequate IOP control after one or more tube repositionings or revisions of the initial aqueous shunt. In this series, the aqueous shunt surgery most often failed because of blocking of the tube ostium by iris, ice membrane, or membrane-induced tube migration. CONCLUSION: Aqueous shunt surgery appears to be an effective method for IOP lowering in some eyes with ice syndrome-related glaucoma when medical treatment or conventional filtration surgeries fail, but additional glaucoma procedures and/or aqueous shunt revisions and tube repositionings are not uncommon.- - - - - - - - - - ranking = 2keywords = membrane (Clic here for more details about this article) |
5/214. Characterization of epithelial downgrowth by confocal microscopy.A 43-year-old white woman with a history of multiple ocular surgeries, including 4 penetrating keratoplasties, developed a concentric retrocorneal membrane at the graft periphery in the right eye. A white-light, tandem, scanning confocal microscope using a 24x/0.60 contact objective was used to examine the right eye in vivo. At the endothelial layer, confocal microscopic images similar to corneal epithelial cells were detected at the graft periphery. Unlike normal endothelial cells, the imaged cells demonstrated easily recognizable nuclei.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
6/214. Deep lamellar keratoplasty using viscoelastic dissection.We describe a technique for performing deep lamellar keratoplasty using viscoelastic dissection. Deep lamellar dissections of the cornea using viscoelastic substances (sodium hyaluronate) were performed on 4 eyes of 4 patients. One patient with keratoconus and another with corneal scarring underwent lamellar keratoplasty using the technique as the sole procedure for visual rehabilitation. Two patients (2 eyes) with opaque corneas underwent deep lamellar dissection with removal of stromal tissue to allow visualization of the anterior segment structures prior to penetrating keratoplasty, thereby facilitating separation of iridocorneal adhesions as the descemet membrane was incised. Deep lamellar dissection was performed without complications related to the procedure in all 4 eyes. The 2 lamellar grafts cleared completely, and both eyes achieved excellent visual acuity with spectacle correction. In the other 2 eyes, deep lamellar dissection provided clear visualization of anterior segment structures during incision of the descemet membrane. Deep lamellar dissection using viscoelastic substances is a useful technique during lamellar keratoplasty.- - - - - - - - - - ranking = 2keywords = membrane (Clic here for more details about this article) |
7/214. Pre-Descemet's membrane hemorrhage after secondary intraocular lens implantation.A 6.0 x 4.0 mm pre-Descemet's membrane hemorrhage with very sharp borders appeared at the temporal portion of the cornea. There was no hyphema in the anterior chamber on the first day after secondary intraocular lens implantation. The hemorrhage resolved almost totally in 1 year without intervention, leaving slight, deep pigmentary changes and minimal diffuse corneal edema.- - - - - - - - - - ranking = 5keywords = membrane (Clic here for more details about this article) |
8/214. Management of oculus fragilis in Ehlers-Danlos type VI.PURPOSE: To describe an alternative, novel surgical approach to the repair of a ruptured globe in the second reported patient with keratoglobus, Ehlers-Danlos type VI, and normal lysyl hydroxylase. methods: Under general anesthesia, a 360 degrees conjunctival peritomy was performed and the epithelium was removed from the keratoglobus cornea. Descemet's membrane and endothelium were removed from a fresh donor corneoscleral ring. An onlay epikeratoplasty was then performed and the entire donor corneoscleral button was secured to the sclera with 9-0 nylon suture. The conjunctiva was brought into position and tacked down over the edge of the donor graft. After 4 months, a full-thickness penetrating keratoplasty was then performed. RESULTS: The patient ultimately had a ruptured globe in the fellow eye and thus required the identical procedure OU. Both eyes were successfully repaired with a final visual acuity OU of 20/100. CONCLUSION: The described surgical approach allowed successful surgical repair of bilateral ruptured globes in a patient with keratoglobus, Ehlers-Danlos type VI, and normal lysyl hydroxylase levels. In the previous report of such a patient by Judisch et al. (1), the attempt at surgical repair was unsuccessful and ended in enucleation. The described surgical technique may be used to treat advanced keratoglobus or oculus fragilis.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
9/214. Cultured corneal epithelia for ocular surface disease.PURPOSE: To evaluate the potential efficacy for autologous and allogeneic expanded corneal epithelial cell transplants derived from harvested limbal corneal epithelial stem cells cultured in vitro for the management of ocular surface disease. methods: Human Subjects. Of the 19 human subjects included, 18 (20 procedures) underwent in vitro cultured corneal epithelial cell transplants using various carriers for the epithelial cells to determine the most efficacious approach. Sixteen patients (18 procedures on 17 eyes) received autologous transplants, and 2 patients (1 procedure each) received allogeneic sibling grafts. The presumed corneal epithelial stem cells from 1 patient did not grow in vitro. The carriers for the expanded corneal epithelial cells included corneal stroma, type 1 collagen (Vitrogen), soft contact lenses, collagen shields, and amniotic membrane for the autologous grafts and only amniotic membrane for the allogeneic sibling grafts. Histologic confirmation was reviewed on selected donor grafts. Amniotic membrane as carrier. Further studies were made to determine whether amniotic membrane might be the best carrier for the expanding corneal epithelial cells. Seventeen different combinations of tryspinization, sonication, scraping, and washing were studied to find the simplest, most effective method for removing the amniotic epithelium while still preserving the histologic appearance of the basement membrane of the amnion. Presumed corneal epithelial stem cells were harvested and expanded in vitro and applied to the amniotic membrane to create a composite graft. Thus, the composite graft consisted of the amniotic membrane from which the original epithelium had been removed without significant histologic damage to the basement membrane, and the expanded corneal epithelial stem cells, which had been applied to and had successfully adhered to the denuded amniotic membrane. Animal model. Twelve rabbits had the ocular surface of 1 eye damaged in a standard manner with direct removal of the presumed limbal stem cells, corneal epithelium, and related epithelium, followed by the application of n-heptanol for 60 seconds. After 6 weeks, all damaged eyes were epithelialized and vascularized. Two such treated eyes were harvested without further treatment, to be used for histologic study as damaged controls. The remaining 10 rabbits received composite grafts (consisting of amniotic membrane with expanded allogeneic rabbit corneal epithelial cell transplants) applied to the ocular surface in a standard manner followed by the application of a contact lens. At 16 days following transplantation, 5 of the rabbits were sacrificed and the corneal rims were removed for histologic study. At 28 days, the remaining rabbits were sacrificed and the previously damaged eyes were harvested for histologic and immunohistochemical study. RESULTS: Human subjects. Of the 19 total patients admitted to the study, the presumed corneal epithelial stem cells of 1 patient did not grow in vitro. Of the remaining 18 patients (20 procedures, 19 eyes), 3 patients had unsuccessful results (3 autologous procedures), 1 patient had a partially successful procedure (allogeneic procedure), and 1 patient had a procedure with an undetermined result at present (allogeneic procedure). One unsuccessful patient had entropion/trichiasis and mechanically removed the graft and eventually went into phthisis. The other 2 unsuccessful patients suffered presumed loss of autologous donor epithelium and recurrence of the ocular surface disease (pterygium). The partially successful patient receiving an allogeneic transplant had infectious keratitis delay of his re-epithelialization; he has only minimal visual improvement but has re-epithelialized. The patient receiving the second allogeneic graft lost his donor epithelium at day 4. Additional donor epithelium was reapplied, but the result is undetermined at present. Amniotic membrane as carrier. The in vitro preparation of the amniotic membrane with corneal epithelial stem cell graft overlay was successful.histology documented removal of the amniotic epithelium and reapplication of corneal epithelial cells. Animal model. The 2 rabbits that had no reparative surgery following standard ocular surface injury had histology and immunopathology consistent with incomplete corneal epithelial stem cell failure with vascularization and scarring of the ocular surface. light microscopy and immunohistologic staining with AE5 confirmed the conjunctival phenotype of the ocular surface repair but also documented the incomplete model. The allogeneic stern cell transplants had varying results. One rabbit had a suppurative infection and lost the graft. Reparative surgery failed in 2 of the rabbits, failed partially in 3 of the rabbits, was partially successful in 3 others, and was successful in 1 rabbit at 28 days. Histologic and immunopathologic study documented successful growth of corneal epithelium onto the recipient surface. CONCLUSIONS: 1. Presumed corneal epithelial stem cells can be harvested safely from the limbus and expanded successfully in vitro. 2. Expanded corneal epithelial cell cultures can be grown onto various carriers, but currently denuded amniotic membrane seems to be the best carrier for ocular surface repair. 3. Expanded corneal epithelial cell transplants appear to resurface damaged ocular surfaces successfully, but cellular tracking and further confirmation are required. 4. Expanded allogeneic corneal epithelial cell transplants are technically possible and may represent alternative treatment modalities for selected ocular surface problems. 5. These techniques potentially offer a new method of restoring a normal ocular surface while minimizing the threat of damage or depletion to the contralateral or sibling limbal corneal epithelial stem cells. 6. The rabbit model was probably incomplete and should be interpreted with caution. The complete eradication of all corneal epithelial stem cells from any eye is difficult, making confirmation of such work challenging. 7. The results of the rabbit model suggest that allogeneic grafts may restore a nearly normal ocular epithelial surface to certain ocular surface injuries.- - - - - - - - - - ranking = 13keywords = membrane (Clic here for more details about this article) |
10/214. Postoperative descemet membrane detachment with maintenance of corneal clarity after trabeculectomy.This case report describes an unusual complication of descemet membrane detachment after anterior chamber reformation to treat a flat anterior chamber and hypotony from a trabeculectomy. This large descemet membrane detachment was unexpectedly associated with a clear cornea. Treatment was conservative, and the descemet membrane detachment spontaneously resolved in 6 months.- - - - - - - - - - ranking = 7keywords = membrane (Clic here for more details about this article) |
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