Management of endothelial decompensation because of glaucoma shunt tube touch by Descemet membrane endothelial keratoplasty and tube revision.

PURPOSE: To describe the trimming of a glaucoma shunt tube with Descemet membrane endothelial keratoplasty (DMEK) for the treatment of endothelial decompensation caused by tube-endothelium touch. METHODS: An 84-year-old man with pseudoexfoliative glaucoma OU had endothelial decompensation because of the touch of the tube of an Ahmed glaucoma valve at the corneal endothelium OS. The best-corrected visual acuity decreased from 20/60 to counting fingers at 3 feet. The patient underwent uncomplicated trimming of the shunt tube and DMEK. RESULTS: After surgery, the cornea became clear, and the best-corrected visual acuity improved to 20/60. The intraocular pressure remained normal (8-12 mm Hg) without antiglaucoma medications, and endothelial cell count remained stable in a follow-up of 12 months. No complications were encountered. CONCLUSIONS: Glaucoma shunt tube trimming with DMEK may be considered in cases of endothelial decompensation because of tube-endothelium touch and may replace penetrating keratoplasty and other posterior lamellar procedures for such cases.

Persistent epithelial defects and ulcers in repeated corneal transplantation: incidence, causative agents, predisposing factors and treatment outcomes.

PURPOSE: To evaluate the occurrence, predisposing factors and outcome of persistent epithelial defects and ulcers complicating repeated corneal transplants. METHODS: The charts of all the patients that underwent repeated corneal transplantation between 1985 and 1998 were retrospectively reviewed for the presence of persistent epithelial defects and ulcers. The repeated corneal transplantation group included 122 regrafts performed in 80 patients. The follow-up period was at least 6 months after the last transplantation (average 31.5 months). RESULTS: Persistent epithelial defects and/or corneal ulcers affected 31 of the 122 regrafts (25.4%) in 23 patients (29%). Of the repeated grafts, 18 had persistent epithelial defects, five had ulcers and eight had persistent epithelial defects complicated by ulcers. Nine of the 31 regrafts (29%) that developed persistent epithelial defects or ulcers had positive bacterial cultures. The survival proportion was similar for regrafts with persistent epithelial defects and with ulcers (p = 0.859), but lower in the regrafted group with persistent epithelial defects and ulcers compared with the entire repeated corneal transplantation group (p < 0.001). In ten patients (43%), one or several eyelid abnormalities and ocular surface disorders were identified. They were more common in repeated keratoplasties with epithelial defects or ulcers than in repeated keratoplasties without them (p < 0.0001). Persistent epithelial defects developed more commonly after cyclocryotherapy for refractory glaucoma (p = 0.001). CONCLUSIONS: Ulcers and persistent epithelial defects are common in repeated corneal transplantation and are associated with poor graft survival. Predisposing factors should be disclosed before regrafting and promptly treated.

Risk factors for failure of simultaneous penetrating keratoplasty and cataract extraction.

OBJECTIVE: To evaluate the indications, complications, and outcomes of simultaneous cataract extraction and penetrating keratoplasty (PKP) and the risk factors for failure of the procedure. SETTING: Tertiary referral medical center. METHODS: In a retrospective noncomparative interventional case series, the charts of 66 consecutive patients (70 eyes) who had simultaneous PKP and cataract extraction using the same surgical technique were reviewed. RESULTS: The mean follow-up was 32.4 months (range 6 to 125 months). The primary corneal graft remained clear in 48 eyes (69%) and failed in 22 eyes (31%). Sixteen eyes with a failed graft (73%) had 1 or 2 repeat keratoplasties; 8 (50%) were successful. At the end of follow-up, 56 eyes (80%) had a clear corneal graft. Nine eyes (41%) with a failed primary graft and 2 eyes (4%) with a clear primary graft had intracapsular cataract extraction (P<.001); 13 eyes (59%) and 46 eyes (96%), respectively, had extracapsular cataract extraction (P<.001). All eyes with a failed primary graft and 18 eyes (37%) with a clear primary graft had postoperative complications (P<.001). Eyes with a failed graft had more postoperative surgical interventions (P<.001). There were no statistical differences between eyes with clear grafts and eyes with failed grafts in sex, age, indications for surgery, corneal graft diameter, intraoperative vitreous loss, and intraocular lens placement. CONCLUSIONS: Intracapsular cataract extraction, postoperative complications, and postoperative surgical interventions may increase the risk for graft failure in simultaneous cataract extraction and PKP. Intraocular lens implantation did not increase the risk for graft failure.

Preexisting and postoperative glaucoma in repeated corneal transplantation.

PURPOSE: To evaluate the incidence, risk factors, management, and visual outcome of postoperative glaucoma in comparison with preexisting glaucoma in repeated corneal transplantation. METHODS: The charts of all the patients who underwent repeated corneal transplantation between 1985 and 1998 were reviewed for the occurrence of preexisting and postoperative glaucoma. Eighty patients underwent 122 repeated corneal transplantations, of which six underwent surgery in both eyes. The mean follow-up period from the primary keratoplasty was 89.5 months and the minimal follow-up period was at least 6 months after the last transplantation. RESULTS: Postoperative glaucoma affected 29 eyes (34%) in 28 patients (35%) with repeated corneal transplantation. Herpetic scar as an indication for transplantation and a history of previous immune graft rejection were more common in patients who developed postoperative glaucoma compared with the entire regrafted group ( p= 0.016 and p< 0.001, respectively). The incidence of glaucoma usually increased with the increased number of keratoplasties. The following types of glaucoma were disclosed: closed angle (59%), corticosteroid induced (21%), open angle (11%), angle recession (3%), aqueous misdirection (3%), and unknown cause (3%). Surgical intervention was required in 62%. Glaucoma was controlled in nine eyes (31%) and resolved following regrafting or discontinuation of corticosteroids in four eyes (14%), of which five (17%) had clear regrafts. Better intraocular pressure control was achieved in those cases that did not require surgical intervention ( p= 0.019). In 15 eyes (52%), regrafts failed due to uncontrolled glaucoma and/or other causes. At the end of the follow-up period, visual acuity was 20/30 to 20/200 in 17%, counting fingers from less than 20 ft in 31%, hand movement/light perception in 35%, and no light perception in 17%. Six of the 86 eyes (7%) in six patients (7.5%) had preexisting glaucoma. Graft clarity and glaucoma control in patients with preexisting glaucoma were similar to those of postkeratoplasty glaucoma (50% had controlled glaucoma and 33% had clear regraft). CONCLUSIONS: Glaucoma, either preexisting or postoperative, is one of the most devastating complications of repeated corneal transplantation and the cause for regraft failure and visual loss even when intensively treated. Close monitoring and early targeted therapy are warranted to increase the survival of repeated corneal transplants in eyes affected by glaucoma.

The expression of hepatitis-C virus antigen by immunohistochemical stain and polymerase chain reaction in corneas of seropositive corneal donors.

Background: Of the donor corneas rejected for transplantation, the largest group is that from donors testing seropositive for hepatitis C virus (HCV). In situations of severe shortage in supply of donor corneal tissue, we may consider the use of seropositive donors for transplantation if we can prove with high certainty the absence of HCV RNA in the donor corneal tissue. Polymerase chain reaction (PCR) is a highly sensitive and specific technique for direct detection of HCV RNA and can be used for this purpose. Nevertheless, it is not applicable for routine clinical use in most eye departments due to its unavailability and cost effectiveness. Purpose: To study the possible use of immunohistochemical method for detection of HCV antigen in corneal tissue of seropositive donors and correlate the results with those of PCR. Immunohistochemical methods have not yet been studied in donor corneal tissue. Materials and methods: Eight corneas of 4 seropositive and 8 corneas of 4 seronegative corneal donors were studied by immunohistochemical and PCR methods for the presence of HCV antigen in their corneal tissue and sera. Results: HCV RNA was not detected in the sera and corneal tissue of all seropositive and seronegative corneal donors by either PCR and immunohistochemical methods. Conclusion: Although the study is too small for conclusive results, the correlation between the immunohistochemical and PCR studies for direct detection of HCV antigen in corneal tissue of seropositive donors may raise the possibility of using the immunohistochemical method for screening of donor corneas for the detection of HCV antigen. A larger prospective study investigating the sensitivity, specificity and clinical applicability of the immunohistochemical method is warranted.