Management of focal limbal stem cell deficiency associated with soft contact lens wear.

PURPOSE: To present the varying manifestations of and the treatment methods for corneal epitheliopathies because of focal limbal stem cell deficiency (LSCD) associated with soft contact lens (SCL) wear. METHODS: The medical records of patients seen at 3 institutions who developed focal LSCD, based on clinical examination, that was attributed to SCL wear were reviewed. Information regarding the patients' demographics, contact lens wearing schedules, medical and surgical treatment modalities, and clinical and visual outcomes were recorded. RESULTS: Eighteen eyes of 10 SCL wearers were found to have varying degrees of corneal epitheliopathy secondary to focal LSCD. Nine of the 10 patients (90%) were women, and the mean age of all patients was 35.1 years (range, 20-58 years). The mean duration of SCL wear was 15.2 years (range, 4-30 years). Two patients wore the lenses for 20 hours per day. Mean follow-up time was 7.0 months (range, 0.25-24 months). Visual acuity at first examination was affected in 10 of the 18 eyes (55.6%) and ranged from 20/30 to hand motions. The focal LSCD was found superiorly in all involved eyes and inferiorly in only 5 of 18 eyes (27.8%). The epitheliopathy resolved or stabilized in 11 eyes (61.1%) with cessation of SCL wear and use of artificial tears. Five eyes required topical corticosteroid eyedrops, and 2 eyes required surgical intervention. One eye had a best spectacle-corrected visual acuity of less than 20/30 at last follow-up. CONCLUSIONS: Focal LSCD can be a result of SCL wear, presenting with varying manifestations. SCL wearers should be monitored routinely and counseled on this possible complication. Early identification of focal LSCD in SCL wearers with subsequent cessation of wear may prevent the need for surgical intervention.

Clinical experience with Acanthamoeba keratitis at the cole eye institute, 1999-2008.

PURPOSE: To review the clinical presentations, risk factors, medical and surgical management, and outcomes of patients with Acanthamoeba keratitis (AK). METHODS: Retrospective review of laboratory and medical records of all patients suspected of having AK from January 1999 through May 2008 at Cole Eye Institute. RESULTS: Twenty-nine eyes of 26 patients were identified as having either culture- or tissue-proven AK or presumed AK based on clinical examination and complete response to full course of treatment. The most common risk factors identified for AK were history of contact lens wear (89.7%) and exposure to contaminated water (27.6%). Clinical presentations included early AK (superficial disease) in 37.9% of eyes or late AK (deep stromal disease with or without epithelial disease) in 62.1% of eyes. All early AK cases had best-corrected visual acuity of 20/30 or better at last follow-up, whereas only 55.6% of late AK cases achieved 20/30 or better. Eight eyes underwent penetrating keratoplasty. One patient demonstrated viable-appearing cysts in the corneal button, despite 15 months of maximum medical treatment and 5 months off all medical treatments. Over the nearly 10-year period, there was no significant increase in the number of cases seen each year. CONCLUSIONS: The most common risk factor for AK continues to be contact lens wear. AK requires prolonged and intense treatment, although good final visual acuity can be achieved. Potentially viable Acanthamoeba cysts can still persist in a noninflamed cornea after extensive medical therapy, supporting the practice that corneal transplantation after presumably resolved cases of AK should be followed with vigilance to detect the earliest signs of recurrent disease.

External refinement of the donor lenticule position during descemet's stripping and automated endothelial keratoplasty.

The authors describe a technique to facilitate the centration of the donor lenticule during Descemet's stripping and automated endothelial keratoplasty. The donor corneal lenticule is unfolded and grossly centered in the anterior chamber using a barbed 30-gauge needle on a 3-cc air syringe or a reverse Sinsky hook. Fine adjustments to center the lenticule can be achieved by applying external pressure to the cornea with a laser in-situ keratomileusis flap roller. This simple technique provides a mechanism for simultaneously removing interface fluid and allows the surgeon to center the donor corneal lenticule without further risk of direct mechanical trauma to the donor endothelium.

Epithelial debridement for the treatment of epithelial basement membrane abnormalities coincident with endothelial disorders.

PURPOSE: To determine if treatment directed at the epithelial basement membrane abnormalities in eyes with endothelial disorder can improve visual acuity and surface irregularity. METHODS: Retrospective interventional case series of 4 eyes of 3 patients with epithelial basement membrane abnormalities and endothelial disorder coincident with Fuchs endothelial corneal dystrophy or iridocorneal endothelial syndrome that had initial treatment directed only at the epithelial basement membrane disorder. RESULTS: In 2 of the 4 eyes undergoing epithelial basement membrane debridement, visual acuity improved by 3 Snellen lines. In the other 2 eyes, the intervention improved visual acuity by 2 lines in 1 eye and no lines in the other, but the procedure allowed for accurate keratometry readings to be obtained for intraocular lens calculations before cataract surgery. CONCLUSIONS: Epithelial basement membrane abnormalities can occur in eyes with endothelial disorder. Treatment of the epithelial basement membrane disorder in these eyes can sometimes improve the regularity of the ocular surface and visual acuity.

Keratoconus diagnosis with optical coherence tomography pachymetry mapping.

OBJECTIVE: To detect abnormal corneal thinning in keratoconus using pachymetry maps measured by high-speed anterior segment optical coherence tomography (OCT). DESIGN: Cross-sectional observational study. PARTICIPANTS: Thirty-seven keratoconic eyes from 21 subjects and 36 eyes from 18 normal subjects. METHODS: The OCT system operated at a 1.3 microm wavelength with a scan rate of 2000 axial scans per second. A pachymetry scan pattern (8 radials, 128 axial scans each; 10 mm diameter) centered at the corneal vertex was used to map the corneal thickness. The pachymetry map was divided into zones by octants and annular rings. Five pachymetric parameters were calculated from the region inside the 5 mm diameter: minimum, minimum-median, inferior-superior (I-S), inferotemporal-superonasal (IT-SN), and the vertical location of the thinnest cornea. The 1-percentile value of the normal group was used to define the diagnostic cutoff. Placido-ring-based corneal topography was obtained for comparison. MAIN OUTCOME MEASURES: The OCT pachymetric parameters and a quantitative topographic keratoconus index (keratometry, I-S, astigmatism, and skew percentage [KISA%]) were used for keratoconus diagnosis. Diagnostic performance was assessed by the area under the receiver operating characteristic (AROC) curve. RESULTS: Keratoconic corneas were thinner. The pachymetric minimum averaged 452.6+/-60.9 microm in keratoconic eyes versus 546+/-23.7 microm in normal eyes. The 1-percentile cutoff was 491.6 microm. The thinnest location was inferiorly displaced in keratoconus (-805+/-749 microm vs -118+/-260 microm; cutoff, -716 microm). The thinning was focal (minimum-median: -95.2+/-41.1 microm vs -45+/-7.7 microm; cutoff, -62.6 microm). Keratoconic maps were more asymmetric (I-S, -44.8+/-28.7 microm vs -9.9+/-9.3 microm; cutoff, -31.3 microm; and IT-SN, -63+/-35.7 microm vs -22+/-11.4 microm; cutoff, -48.2 microm). Keratoconic eyes had a higher KISA% index (2641+/-5024 vs 21+/-19). All differences were statistically significant (t test, P<0.0001). Applying the diagnostic criteria of any 1 OCT pachymetric parameter below the keratoconus cutoff yielded an AROC of 0.99, which was marginally better (P = .09) than the KISA% topographic index (AROC, 0.91). CONCLUSIONS: Optical coherence tomography pachymetry maps accurately detected the characteristic abnormal corneal thinning in keratoconic eyes. This method was at least as sensitive and specific as the topographic KISA. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Amantadine-associated corneal edema potentially irreversible even after cessation of the medication.

PURPOSE: To describe the clinical features of 3 patients with amantadine-associated corneal edema, including the histopathologic findings from 1 patient who underwent corneal transplantation for irreversible corneal edema. DESIGN: Interventional case series. PARTICIPANTS: Three patients who sought treatment at the authors' institution with abrupt-onset, bilateral, diffuse corneal edema associated with systemic amantadine use. METHODS: Retrospective chart review. MAIN OUTCOME MEASURES: Visual acuity, corneal thickness, slit-lamp observations, and histopathologic findings. RESULTS: The duration of use of amantadine ranged from 2 months to 6 years before onset of corneal edema. Discontinuation of amantadine resulted in resolution of corneal edema in both eyes of 2 patients. A third patient underwent a full-thickness corneal transplantation, and subsequently, edema developed in the grafted cornea. Cessation of amantadine therapy in this patient resulted in resolution of corneal edema in both eyes, but the ungrafted corneal eventually decompensated and became edematous, requiring corneal transplantation. Histopathologic analysis of the cornea buttons showed significant loss of endothelial cells. CONCLUSIONS: Amantadine can cause corneal edema that begins a few months to several years after institution of therapy, and the edema can occur even in a corneal graft. Prolonged corneal edema in the setting of amantadine use can be irreversible. In cases of corneal edema without an obvious causative disease, the systemic medication list of the patient must be reviewed, and amantadine must be considered as a possible cause.

Ocular TRUST: nationwide antimicrobial susceptibility patterns in ocular isolates.

PURPOSE: Ocular Tracking Resistance in U.S. Today (TRUST) annually evaluates in vitro antimicrobial susceptibility of Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae to ciprofloxacin, gatifloxacin, levofloxacin, moxifloxacin, penicillin, azithromycin, tobramycin, trimethoprim, and polymyxin B in national samples of ocular isolates. DESIGN: Laboratory investigation. METHODS: Prospectively collected ocular isolates (197 S. aureus, 49 S. pneumoniae, and 32 H. influenzae) from 35 institutions and archived ocular isolates (760 S. pneumoniae and 356 H. influenzae) from 34 institutions were tested by an independent, central laboratory. Mean minimum inhibitory concentrations that would inhibit growth of 90% of the tested isolates (MIC(90)) were interpreted as susceptible, intermediate, or resistant according to standardized breakpoints for systemic treatment. S. aureus isolates were classified as methicillin susceptible (MSSA) or methicillin resistant (MRSA). RESULTS: MSSA or MRSA susceptibility patterns were virtually identical for the fluoroquinolones, that is, MSSA susceptibility was 79.9% to 81.1% and MRSA susceptibility was 15.2%. Trimethoprim was the only agent tested with high activity against MRSA. All S. pneumoniae isolates were susceptible to gatifloxacin, levofloxacin, and moxifloxacin; 89.8% were susceptible to ciprofloxacin. H. influenzae isolates were 100% susceptible to all tested agents but trimethoprim. Ocular TRUST 1 data were consistent with the eight-year longitudinal sample of archived ocular isolates. CONCLUSIONS: The fluoroquinolones were consistently active in MSSA, S. pneumoniae, and H. influenzae. After more than a decade of intensive ciprofloxacin and levofloxacin use as systemic therapy, 100% of ocular S. pneumoniae isolates were susceptible to gatifloxacin, levofloxacin, and moxifloxacin; nonsusceptibility to ciprofloxacin was less than 15%. High-level in vitro MRSA resistance suggests the need to consider alternative therapy to fluoroquinolones when MRSA is a likely pathogen.

Multivariate model of refractive shift in Descemet-stripping automated endothelial keratoplasty.

PURPOSE: To relate in situ graft shape in Descemet-stripping automated endothelial keratoplasty (DSAEK) to surgically induced refractive error. SETTING: Academic eye institute. METHODS: High frequency arc-scanning ultrasound was performed in 7 patients enrolled in a prospective study of microkeratome-assisted endothelial keratoplasty approved by the Investigative Review Board. A region of interest spanning the horizontal meridian was defined for analysis of epithelial, host, graft, and total corneal thicknesses. Graft thickness profiles were fit by quadratic polynomials where the 2nd-order coefficients represent the posterior corneal curvature contributed by the graft. The curvature coefficient and central graft thickness were analyzed as predictors of induced refractive error. RESULTS: At final follow-up (mean 5.9 months +/- 3.2 [SD]), 3 patients had a hyperopic shift (+2.50 diopters [D] each), 3 had insignificant (< 0.50 D) refractive shifts, and 1 had a myopic shift. In the group with hyperopic shift, a negative lens effect was predicted by positive curvature coefficients, representing grafts that were thinner centrally than peripherally (mean +22.72 microm/mm(2); range +4.95 to +45.17 microm/mm(2)). In the group with minimal refractive shift, coefficients were less positive (mean +7.28 microm/mm(2); range +2.01 to +13.82 microm/mm(2)). The patient with a myopic shift (-1.00 D) had the only negative curvature coefficient (-0.64 microm/mm(2)). In a 2-predictor model of refractive shift, central graft thickness and the curvature coefficient together accounted for 86% of the variance in the refractive response to DSAEK (P = .025). CONCLUSION: Nonuniform thickness profiles and variable central graft thicknesses both contribute to refractive shift after DSAEK.

Late repeat Descemet-stripping automated endothelial keratoplasty.

PURPOSE: To report the outcomes of 2 patients who underwent repeat Descemet-stripping automated endothelial keratoplasty (DSAEK) 13 and 23 months after their primary surgeries. METHODS: Two patients underwent repeat DSAEK for late graft failure at approximately 1 and 2 years, respectively. The operative procedure involved removing the failed graft and replacing it with new donor tissue. RESULTS: The postoperative visual recovery was similar to the visual outcomes of primary DSAEK surgery, with both patients achieving 20/30 or better best spectacle-corrected visual acuity within 3 months. There were no signs of interface scarring after surgical removal of the failed donor disc. CONCLUSIONS: Late repeat DSAEK can result in rapid visual recovery without interface scarring.

Reopening of previously closed macular holes after cataract extraction.

PURPOSE: To evaluate the frequency of reopening of macular holes after cataract extraction. DESIGN: Retrospective, comparative, consecutive case series. METHODS: Two hundred and eleven eyes with idiopathic macular holes closed by vitrectomy were divided into four groups: Group 1: prior cataract extraction; Group 2: vitrectomy then cataract extraction; Group 3: vitrectomy only; and Group 4: vitrectomy and cataract extraction as a combined procedure. The main outcome measure of macular hole reopening was evaluated in relationship to multiple variables. RESULTS: Two hundred and eleven eyes were included: Group 1: 56 eyes; Group 2: 86 eyes; Group 3: 41 eyes; and Group 4: 28 eyes. Twenty-four macular holes reopened (11%) (mean follow-up 26.6 months, range, three to 118 months). The greatest number of macular hole reopenings, 17 (20%), were in Group 2. Cox multivariate analysis failed to demonstrate an association between duration of hole, serum use, internal limiting membrane peeling, or stage and reopening of a macular hole. Cox analysis showed a four-fold increased risk of reopening in Group 2 eyes (95% confidence interval [CI]: 1.7 to 11.2; P = .002). Eyes with cystoid macular edema after cataract extraction had a seven-fold increased risk of macular hole reopening (7.72; 95% CI: 2.79 to 21.3; P < .0005). Kaplan-Meier analysis showed increased rates of macular hole reopening in Group 2 eyes compared to the other 3 groups combined (log-rank P < .00005). CONCLUSIONS: Cataract extraction after successful vitrectomy for macular hole, when complicated by cystoid macular edema (CME), may increase the risk of macular hole reopening.

Anterior segment and external ocular disorders associated with human immunodeficiency virus disease.

The eye is a common site for complications of human immunodeficiency virus (HIV) infection. Although cytomegalovirus retinitis remains the most prevalent of the blinding ocular disorders that can occur in individuals with the acquired immunodeficiency syndrome (AIDS), several important HIV-associated disorders may involve the anterior segment, ocular surface, and adnexae. Some of these entities, such as Kaposi sarcoma, were well described, but uncommon, before the HIV epidemic. Others, like microsporidial keratoconjunctivitis, have presentations that differ between affected individuals with HIV disease and those from the general population who are immunocompetent. The treatment of many of these diseases is challenging because of host immunodeficiency. Survival after the diagnosis of AIDS has increased among individuals with HIV disease because of more effective antiretroviral therapies and improved prophylaxis against, and treatment of, opportunistic infections. This longer survival may lead to an increased prevalence of anterior segment and external ocular disorders. In addition, the evaluation and management of disorders such as blepharitis and dry eye, which were previously overshadowed by more severe, blinding disorders, may demand increased attention, as the general health of this population improves. Not all individuals infected with HIV receive potent antiretroviral therapy, however, because of socioeconomic or other factors, and others will be intolerant of these drugs or experience drug failure. Ophthalmologists must, therefore, still be aware of the ocular findings that develop in the setting of severe immunosuppression. This article reviews the spectrum of HIV-associated anterior segment and external ocular disorders, with recommendations for their evaluation and management.

Visual acuity, refractive error, and endothelial cell density six months after Descemet stripping and automated endothelial keratoplasty (DSAEK).

PURPOSE: To evaluate visual acuity, refractive outcomes, and endothelial cell density 6 months after Descemet stripping and automated endothelial keratoplasty (DSAEK). METHODS: We performed an institutional review board-approved prospective study of a surgical case series of 34 patients at 2 institutions undergoing DSAEK for Fuchs endothelial dystrophy, pseudophakic bullous keratopathy, or aphakic bullous keratopathy with or without simultaneous phacoemulsification and intraocular lens implantation. Clinical outcomes, including best spectacle-corrected visual acuity (BSCVA), spherical equivalent refraction, and refractive astigmatism and topographic or keratometric astigmatism, were assessed at the 6-month postoperative examination and compared with preoperative values with paired Student t tests. The change in endothelial cell density from the eye bank examination to 6 months after transplantation was similarly evaluated. RESULTS: BSCVA averaged 20/99 preoperatively and 20/42 postoperatively (P < 0.0001). After DSAEK, 30 (88.2%) of 34 patients showed improved BSCVA, and 21 (61.8%) of the 34 patients achieved a BSCVA of 20/40 or better. For patients not undergoing simultaneous phacoemulsification and intraocular lens implantation, a hyperopic shift in refraction of 1.19 +/- 1.32 D was noted. Refractive astigmatism, topographic astigmatism, and keratometry showed no statistically significant change. Endothelial cell density of donor corneas averaged 2826 +/- 370 cells/mm, whereas the mean postoperative density was 1396 +/- 440 cells/mm. This finding corresponded to an average loss of 1426 cells/mm (50% loss; P = 0.0001). The first half of cases experienced an average cell loss of 1674 cells/mm (59% loss) compared with 1181 (41% loss) in the second half of cases (P = 0.005). Three (9%) of 34 grafts experienced iatrogenic graft failure and required reoperation with new donor tissue. Also, 9 (27%) of 34 grafts experienced dislocation in the early postoperative period and required repositioning. CONCLUSIONS: In this prospective study of DSAEK for bullous keratopathy and Fuchs endothelial corneal dystrophy, improvement of visual acuity was achieved with only a mild tendency toward hyperopic shift and without significant induced astigmatism. Endothelial cell loss was significant, however, and may be related to surgical experience.

Use of an air-fluid exchange system to promote graft adhesion during Descemet's stripping automated endothelial keratoplasty.

Dislocation of the graft is a well-recognized complication of Descemet's stripping automated endothelial keratoplasty (DSAEK). We describe a technique to promote adhesion of the graft during DSAEK using an anterior chamber air-fluid infusion and exchange for direct control of the pressure and medium used to tamponade the graft against the host stroma.

Simple technique to unfold the donor corneal lenticule during Descemet's stripping and automated endothelial keratoplasty.

We describe a technique to facilitate unfolding and prevent inversion of the donor corneal lenticule during Descemet's stripping and automated endothelial keratoplasty (DSAEK). The donor corneal lenticule is unfolded in the anterior chamber using a bent 30-gauge needle on a 3 cc air syringe. The needle tip is used to pinion the edge of the lenticule while an air bubble is simultaneously injected between the folded edges of the donor graft. A gentian-violet dye mark placed on the peripheral stromal surface of the donor lenticule is used to confirm proper graft orientation. The simple technique of simultaneously fixating the donor lenticule while injecting air ensures that the graft unfolds correctly and minimizes potential mechanical trauma to the endothelium.

Narrow-strip conjunctival autograft for treatment of pterygium.

PURPOSE: To determine the efficacy of narrow-strip conjunctival autograft surgery in the treatment of pterygium. DESIGN: Retrospective noncomparative interventional case series. PARTICIPANTS: Twenty-one consecutive interventions between 1994 and 2005 in 20 eyes of 18 patients for primary (n = 17 cases) or recurrent (n = 4 cases) pterygia. INTERVENTION: Surgical excision of the pterygium and conjunctival transplantation with a narrow-strip technique. In all cases, a 2-mm-wide autograft was secured adjacent and posterior to the limbus, leaving a 2- to 3-mm zone of bare sclera between the graft and the anterior margin of the conjunctival wound. All conjunctival margins were secured by suture to bare sclera. MAIN OUTCOME MEASURE: Recurrence of pterygium at 12 months. RESULTS: Mean follow-up after surgery was 41 months (median, 42; range, 4-132). At 1 year and all time points thereafter, 18 of 19 (94.7%) cases were free of recurrence. One patient was lost to follow-up at 4 months, and another died after 9 months of follow-up. The lone recurrence occurred inferiorly in an eye that had undergone an adjacent narrow-strip conjunctival transplantation 6 months previously for a recurrent temporal pterygium. The same patient remains recurrence-free 67 months after inferior pterygium excision and a second narrow-strip autograft surgery. CONCLUSION: Narrow-strip conjunctival autografting appears to be an effective surgical technique in preventing pterygium recurrence. Creating an intervening bare sclera area between the secured conjunctival graft and the anterior margin of the conjunctival wound may be important in preventing recurrence.

Dysfunctional tear syndrome: a Delphi approach to treatment recommendations.

PURPOSE: To develop current treatment recommendations for dry eye disease from consensus of expert advice. METHODS: Of 25 preselected international specialists on dry eye, 17 agreed to participate in a modified, 2-round Delphi panel approach. Based on available literature and standards of care, a survey was presented to each panelist. A two-thirds majority was used for consensus building from responses obtained. Treatment algorithms were created. Treatment recommendations for different types and severity levels of dry eye disease were the main outcome. RESULTS: A new term for dry eye disease was proposed: dysfunctional tear syndrome (DTS). Treatment recommendations were based primarily on patient symptoms and signs. Available diagnostic tests were considered of secondary importance in guiding therapy. Development of algorithms was based on the presence or absence of lid margin disease and disturbances of tear distribution and clearance. Disease severity was considered the most important factor for treatment decision-making and was categorized into 4 levels. Severity was assessed on the basis of tear substitute requirements, symptoms of ocular discomfort, and visual disturbance. Clinical signs present in lids, tear film, conjunctiva, and cornea were also used for categorization of severity. Consensus was reached on treatment algorithms for DTS with and without concurrent lid disease. CONCLUSION: Panelist opinion relied on symptoms and signs (not tests) for selection of treatment strategies. Therapy is chosen to match disease severity and presence versus absence of lid margin disease or tear distribution and clearance disturbances.

A combined technique for surgical repair of Descemet's membrane detachments.

BACKGROUND AND OBJECTIVE: Descemet's membrane detachments are an uncommon complication after cataract surgery that can result in severe visual loss. A combined technique of intracameral gas injection and transcorneal suturing for the repair of Descemet's membrane detachments is described. PATIENTS AND METHODS: In this interventional case series, four cases of Descemet's membrane detachments with associated corneal edema observed following cataract surgery were successfully repaired using a combined technique of intracameral gas injection and transcorneal suturing. RESULTS: In all cases, Descemet's membranes were successfully reattached using the aforementioned technique. In three cases, the associated corneal edema resolved postoperatively. In the fourth case, the patient required a penetrating keratoplasty for persistent corneal edema despite immediate anatomical success following reattachment. CONCLUSIONS: Combined intracameral gas and transcorneal suturing appears to be an effective technique in the repair of Descemet's membrane detachments. Early intervention may prevent persistent or recurrent corneal edema.

Immunohistochemical detection and Western blot analysis of nitrated protein in stored human corneal epithelium.

While the production of nitric oxide by human corneas in storage has recently been demonstrated, protein nitration as a result of this production has not been demonstrated. In this study, nitrated protein accumulation in the epithelium of stored human corneas was assessed. One half of five donor corneas maintained in storage media for 3 days were prepared for immunohistochemical studies. The other halves remained in storage media for 7 additional days and were also processed for immunohistochemistry. Mouse monoclonal antibody to nitrotyrosine adducts was used to define the localisation of these epitopes. The density of antibody staining was observed and quantified on a digital camera system and statistically analysed. Immunostaining in the epithelium was greater in tissues recovered after 10 days in storage compared to the intensity of staining after 3 days of storage (p<0.0001). No staining was evident in the epithelium in sections exposed to non-immune mouse IgG. Western blot analysis was performed on epithelial cells scraped from corneal surfaces of one-half of four donor corneas in storage for 3 days and from the other half at 10 days of storage. Nitrated BSA was used as a positive control. After extraction and homogenisation, identical protein concentrations of each sample were loaded per lane on 10% gels and subjected to SDS-PAGE. Proteins were blotted and probed with the anti-nitrotyrosine antibody. Western blot immunoreactivity was detected in epithelial samples at the 3 and 10 day recovery times with the latter samples showing greater staining intensity. Nitrated protein, thought to indicate toxic peroxynitrite formation, accumulates in the human corneal epithelium with time of storage. Our study shows that there is an association between increased nitrated protein and storage time.

A device to facilitate limbal stem cell procurement from eye bank donor tissue for keratolimbal allograft procedures.

PURPOSE: To develop a device that facilitates the procurement of corneal limbal stem cell grafts for keratolimbal allograft procedures used in the treatment of ocular surface disease associated with stem cell deficiency. DESIGN: Description of device design and technique for use. METHODS: The device is composed of a pedestal with a convex surface mounted to a flat platform. A corneoscleral button placed endothelial side down and centrally upon the convexity is secured by suction conveyed through a hollowed core in the pedestal that connects to fenestrated openings on the convex surface. A donut-shaped stainless steel ring placed on tension by springs braces the peripheral tissue. A circular corneal incision is created of a desired thickness by a suction trephine, and a crescent blade is utilized to peripherally dissect a donut-shaped keratolimbal allograft. RESULTS: This device facilitated the harvesting of the keratolimbal allograft tissue from four eye bank donor practice corneoscleral buttons and was then used to successfully procure grafts from six corneoscleral buttons used in three keratolimbal allograft procedures in three patients, one each with aniridia, alkali burn, and drug-induced limbal stem cell deficiency. CONCLUSIONS: The described device effectively facilitates procurement of corneoscleral buttons for keratolimbal allograft procedures. It appears to offer advantages over freehanded techniques and previously described devices used for the same purpose.