Comparison of Donor Cornea Endothelial Cell Density Determined by Eye Banks and by a Central Reading Center in the Cornea Preservation Time Study.

PURPOSE: To evaluate agreement between eye banks (EBs) and a reading center on endothelial cell density (ECD) determinations in the Cornea Preservation Time Study. METHODS: The Cornea Image Analysis Reading Center (CIARC) performed variable frame image analysis on EB-obtained-preoperative central endothelial images (after lamellar dissection for Descemet stripping automated endothelial keratoplasty by the EBs or before shipping, if surgeon prepared) to determine ECD. The EBs performed their usual method of ECD determination. The CIARC and EBs also provided ECD determinations from screening central endothelial images taken by the EBs during donor evaluation. Two independent masked CIARC readers determined ECD with measurements averaged. RESULTS: The mean preoperative ECD was 15 cells/mm greater by the EBs than by CIARC (N = 1286, P < 0.001) with 95% limits of agreement of (-644, 675 cells/mm). The limits of agreement in preoperative ECD were wider in the After-Lamellar-Dissection Group (-687, 683 cells/mm) than in the Before Shipping Group [(-505, 633 cells/mm); P = 0.03]. The EBs-determined preoperative ECD was within 10% of the CIARC-determined ECD for 886 (69%) image sets, with 236 (18%) higher by >10% and 164 (13%) lower by >10%. Excellent agreement appeared between the EBs and CIARC when 100-300 cells could be analyzed in contrast to <100 cells (SD = 308 cells/mm vs. SD = 603 cells/mm; P < 0.001). CONCLUSIONS: The mean ECD by the EBs and CIARC were similar, but there was considerable variability between determinations for individual corneas. Agreement improved between the 2 measurements when more than 100 cells were able to be analyzed.

Factors Associated With Graft Rejection in the Cornea Preservation Time Study.

PURPOSE: To identify factors related to graft rejection following Descemet stripping automated endothelial keratoplasty (DSAEK) in the Cornea Preservation Time Study (CPTS). DESIGN: Cohort study within a multicenter randomized clinical trial. METHODS: A total of 1330 eyes of 1090 subjects undergoing DSAEK were randomized to receive a donor cornea with preservation time (PT) of 0-7 days (n = 675) or 8-14 days (n = 655) and followed for 3 years. Central endothelial cell density (ECD) was determined by a central image analysis reading center. Multivariable Cox models adjusted for PT, recipient diagnosis, and surgeon effect were used to identify factors associated with rejection. RESULTS: Cumulative probability of definite graft rejection was 3.6% (99% confidence interval 2.5%-5.3%). Younger recipient age was associated with graft rejection (P < .001; hazard ratio: 0.53 [0.33, 0.83] per decade). PT, donor-recipient sex mismatch, recipient diagnosis, recipient race, graft size, discontinuation of topical corticosteroids and immune-modulators, prior immunizations within 3 months, and prior glaucoma surgery were not associated with rejection (P > .01). Among clear grafts with an ECD measurement at baseline and 3 years (n = 913), endothelial cell loss (ECL) was greater in eyes that experienced a rejection episode (n = 27) than in those that did not (n = 886) (48% vs 38%, P = .03). Twelve of 44 eyes (27%) with definite graft rejection subsequently failed, comprising 15% of the 79 failures in the CPTS. CONCLUSIONS: Graft rejection is uncommon after DSAEK and more likely with younger age, in a study cohort mostly > 50 years old. Rejection increases ECL, but it is not a leading cause of DSAEK failure.

Long-Term Follow-Up of Amniotic Membrane Graft for the Treatment of Symblepharon in a Patient With Recessive Dystrophic Epidermolysis Bullosa.

PURPOSE: To report a case of symblepharon due to epidermolysis bullosa (EB), surgical treatment, and follow-up to 14 years. METHODS: A 17-year-old white female with recessive dystrophic EB presented with decreased vision due to extensive symblepharon OU. There was opacification and neovascularization of the cornea OU with limited motility. RESULTS: The symblepharon was surgically lysed, anterior lamellar keratectomy performed, and amniotic membrane graft transplanted to the cornea and palpebral conjunctiva, first in the OS and subsequently in the OD. Visual acuity improved from counting fingers to 20/40 in the OS and from 20/200 to 20/70 in the OD at 2 months and 6 weeks postoperatively, respectively, with minimal symblepharon, mild corneal scarring, neovascularization, and haze of OU. She recovered full ductions, but noted diplopia and had a 35 prism diopter exotropia. Symblepharon resolved after 6 months, and alignment improved to 4 prism diopter exophoria. At 14 years follow-up, visual acuity was 20/20 in the OD and 20/30 in the OS, with clear cornea, maintained on fluorometholone 0.1% one drop OU at bedtime. CONCLUSIONS: Surgical symblepharolysis, superficial lamellar keratectomy, and amniotic membrane graft transplantation were effective for our patient with recessive dystrophic EB. Her postoperative exotropia resolved over time with monitoring and convergence exercises.

The use of a virtual reality surgical simulator for cataract surgical skill assessment with 6 months of intervening operating room experience.

PURPOSE: To evaluate a haptic-based simulator, MicroVisTouch™, as an assessment tool for capsulorhexis performance in cataract surgery. The study is a prospective, unmasked, nonrandomized dual academic institution study conducted at the Wilmer Eye Institute at Johns Hopkins Medical Center (Baltimore, MD, USA) and King Khaled Eye Specialist Hospital (Riyadh, Saudi Arabia). METHODS: This prospective study evaluated capsulorhexis simulator performance in 78 ophthalmology residents in the US and Saudi Arabia in the first round of testing and 40 residents in a second round for follow-up. RESULTS: Four variables (circularity, accuracy, fluency, and overall) were tested by the simulator and graded on a 0-100 scale. Circularity (42%), accuracy (55%), and fluency (3%) were compiled to give an overall score. Capsulorhexis performance was retested in the original cohort 6 months after baseline assessment. Average scores in all measured metrics demonstrated statistically significant improvement (except for circularity, which trended toward improvement) after baseline assessment. A reduction in standard deviation and improvement in process capability indices over the 6-month period was also observed. CONCLUSION: An interval objective improvement in capsulorhexis skill on a haptic-enabled cataract surgery simulator was associated with intervening operating room experience. Further work investigating the role of formalized simulator training programs requiring independent simulator use must be studied to determine its usefulness as an evaluation tool.

Surgical outcomes of Baerveldt implants in pediatric glaucoma patients.

PURPOSE: To evaluate the efficacy of the Baerveldt glaucoma implant (BGI) in children. METHODS: The medical records of pediatric glaucoma patients aged 5 months to 19 years who underwent BGI placement by a single surgeon (JCS) between January 1, 2000, and March 1, 2010, were retrospectively reviewed. Patients were evaluated at 3-9 months, 12-18 months, and 24-30 months after surgery. We defined surgical success as a postoperative intraocular pressure (IOP) of >6 mm Hg and <21 mm Hg, without additional glaucoma surgery, loss of light perception, removal of the BGI, chronic hypotony, retinal detachment, malignant glaucoma, endophthalmitis, or phthisis bulbi. Additional outcome measures were tube erosion, corneal decompensation, tube retraction, visual acuity, clinical bleb encapsulation, and choroidal detachment. RESULTS: A total of 45 eyes of 36 patients were included. The mean preoperative IOP was 31.6 ± 5.0 mm Hg; the mean postoperative IOP, 16.3 ± 5.1 mm Hg at 3-9 months, 19.5 ± 4.8 mm Hg at 12-18 months, and 18.3 ± 4.8 mm Hg at 24-30 months. Cumulative probability of success was 93.3% at 3-9 months, 86.7% at 12-18 months, and 86.7% at 24-30 months. Overall, 6 eyes failed within 30 months because of uncontrolled IOP (3 eyes), replacement of the glaucoma drainage device (2 eyes), and no light perception (1 eye). CONCLUSIONS: In this study cohort, BGI surgery effectively reduced IOP in pediatric patients with refractory glaucoma.

Descemet stripping with automated endothelial keratoplasty: A comparative study of outcome in patients with preexisting glaucoma.

PURPOSE: To compare postoperative complications after Descemet stripping with automated endothelial keratoplasty (DSAEK) in patients with and without glaucoma. METHODS: For this retrospective study a series of 298 DSAEK cases performed at the Doheny Eye Institute were taken, we compared postoperative complications in eyes with glaucoma on medication (55) or with previous glaucoma surgeries (64) with a time-matched group of all other DSAEK cases (179, control). RESULTS: With a mean follow-up of 1.85 ± 1.12 years, the complication rates were 12.8%, 11.1%, and 26.8% for postoperative graft detachment, graft failure, and IOP elevation, respectively. Graft detachment was an independent risk factor for graft failure (odds ratio OR = 12.35, 95% confidence interval CI [5.46-27.90], P < 0.001). Graft detachment was not associated with either history of glaucoma or glaucoma surgery (P > 0.05). Glaucoma on medication had no increased risks of graft failure compared to normal eyes (P = 0.38). However, increased risk of failure was seen in eyes with prior incisional glaucoma surgeries (OR = 4.26, 95% CI [1.87-9.71], P < 0.001). Medically managed glaucoma has increased risks of postoperative IOP elevation (OR = 2.39, 95% CI [1.25-4.57], P = 0.013), whereas surgically managed glaucoma has no significant elevation (P = 0.23). Elevation of IOP was not significantly correlated with graft failure (P = 0.21). CONCLUSION: DSAEK is the preferred treatment for corneal endothelial dystrophy. We observed that having glaucoma or glaucoma surgery is not associated with graft detachment. A history of glaucoma surgery and postoperative graft detachment appeared to be important risk factors for graft failure. And more studies are indicated to study long-term IOP evolution in post-DSAEK patients and its association with graft survival.

Primary and secondary congenital glaucoma: baseline features from a registry at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia.

PURPOSE: To compare the demographic and clinical distribution of primary and secondary congenital glaucoma from a registry at King Khaled Eye Specialist Hospital. DESIGN: Registry-based cohort study. METHODS: Review of registry data that included new patients with congenital glaucoma seen between 2001 and 2003 (29 months); analysis of the demographic data and clinical features of primary and secondary congenital glaucoma at presentation. RESULTS: A total of 325 eyes of 180 patients were included. Most patients had primary congenital glaucoma (80%). The mean (± SD) age at presentation for primary congenital glaucoma was 3.8 ± 10.7 months and for secondary congenital glaucoma was 4.3 ± 7.9 months. Most primary congenital glaucoma and secondary congenital glaucoma patients had bilateral disease (82.6%; 74.3%). Primary congenital glaucoma was equally distributed by sex but secondary congenital glaucoma was 1.5-fold more common in male patients. A positive family history was elicited in 30%, and almost 60% had a history of consanguinity in both groups. The mean intraocular pressure and corneal diameter were comparable in both groups but the axial length was significantly longer in primary congenital glaucoma and cup-to-disc (C/D) ratio greater in secondary congenital glaucoma. In the primary congenital glaucoma group, corneal haze showed a significant relationship with most clinical parameters. In primary congenital glaucoma, a positive correlation was noted between age at presentation and increasing corneal diameter and axial length but a negative relationship was noted with C/D ratio and corneal haze, whereas for secondary congenital glaucoma only axial length was positively correlated. CONCLUSION: The congenital glaucoma registry provides unique baseline data on primary congenital glaucoma and secondary congenital glaucoma in Saudi Arabia that will enable us to better understand the disease in the Kingdom and region.

Dual laser-assisted lamellar anterior keratoplasty with top hat graft: a laboratory study.

OBJECTIVES: To develop a dual laser-assisted lamellar anterior keratoplasty (LALAK) technique, using excimer and femtosecond lasers to perform surgery on eye bank eyes. METHODS: First, we compared corneal stromal surfaces produced by (1) deep excimer ablation, (2) femtosecond lamellar cuts, and (3) manual dissection and evaluated the effect of excimer laser smoothing with fluid masking on each surface. Masked observers graded scanning electron microscopy images on a 5-point roughness scale. Then, we performed a 6-mm diameter excimer laser phototherapeutic keratectomy ablation to a residual bed thickness of 200 µm, followed by laser smoothing. We used the femtosecond laser to cut donors in a modified top hat design with a thin tapered brim, which fitted into a manually dissected circumferential pocket at the base of the recipient bed. Fourier domain optical coherence tomography was used to measure corneal pachymetry and evaluate graft fit. RESULTS: Deep excimer ablation with smoothing (n = 4) produced a significantly (P < 0.05) smoother surface (grade = 3.5) than deep excimer alone (n = 4, grade = 3.8) or manual dissection with (n = 1, grade = 3.8) and without smoothing (n = 1, grade = 4.8). Deep femtosecond cuts (n = 2) produced macroscopic concentric ridges on the stromal surface. Experimental LALAK was performed on 4 recipients prepared by deep excimer ablation and 4 donors cut with the femtosecond laser. After suturing, good peripheral graft-host match was observed on Fourier domain optical coherence tomography imaging. CONCLUSION: These preliminary studies show that the LALAK technique permits improved interface smoothness and graft edge matching. Clinical trials are needed to determine whether these improvements can translate to better vision.

Early surgical debridement in the management of infectious scleritis after pterygium excision.

PURPOSE: The purpose of this study was to report outcomes of infectious scleritis after pterygium surgery, managed with antibiotic therapies and early scleral debridement. METHODS: Retrospective chart review of 13 consecutive cases of infectious scleritis after pterygium excision between 1999 and 2009 was conducted. Collected data included prior medical and surgical history, latency period between pterygium surgery and presentation of infectious scleritis, culture and histopathologic findings, antibiotic regimen, length of hospital stay, visual acuity before and after treatment, and complications. RESULTS: Median follow-up was at 14 months. Twelve patients underwent prompt surgical debridement after infectious scleritis diagnosis (median, 2.5 days). Debridement was delayed in one patient. Median hospital stay was 3 days. Best-corrected visual acuity improved in ten patients, remained stable in one patient, and decreased in two patients following treatment. Complications included scleral thinning requiring scleral patch graft (1/13), glaucoma (3/13), and progression to phthisis bulbi (1/13). No patients required enucleation. CONCLUSIONS: In contrast to the generally poor outcomes in the literature, early surgical debridement of pterygium-associated infectious scleritis appears to offer improved prognosis.

Long term comparison between single stage Baerveldt and Ahmed glaucoma implants in pediatric glaucoma.

PURPOSE: To compare the long term intraocular pressure control in pediatric glaucoma patients who underwent single stage Baerveldt glaucoma valve and Ahmed glaucoma valve S2 implantation. STUDY DESIGN: A retrospective study was conducted to analyze the data of patients with single stage Baerveldt glaucoma valve and Ahmed valve implantation at Children Hospital Los Angeles. METHODS: Medical records of patients were reviewed retrospectively and divided into two groups. All cases received single stage valve implantation in which the tube was inserted primarily into the anterior chamber. In cases with Baerveldt implants, the silicone tube was ligated near its plate location with a single absorbable suture. Group 1 included patients with Baerveldt glaucoma implant model BG 101-350, while group 2 included patients with Ahmed valve implant model S-2. Patients' data collected ranged over the period from 2001 to 2008. The minimum follow up period was 6 month; maximum follow up period was 8 years. All patients were below 18 years of age. Success was considered if last postoperative IOP was between 8 and 24 mm Hg (with or without medications), no additional glaucoma surgery after valve implantation, and absence of visually significant complications. RESULTS: Group 1 included 20 cases and group 2 included 11 cases. Long term success rate based on criterion defined was 80% for group 1 (Baerveldt) with average IOP postoperatively on last follow-up of 19.6 mm Hg. In group 2 (Ahmed), average postoperative pressure was 24 mm Hg with 6 out of 11 considered successful based on criterion giving 54.5% success rate. CONCLUSION: In the long term, single stage Baerveldt implantation appears to control pressure well in pediatric glaucoma.

Community opinions in the management of corneal ulcers and ophthalmic antibiotics: a survey of 4 states.

OBJECTIVE: To evaluate the ophthalmic community's current opinions of the management of bacterial keratitis and usage of the currently available ophthalmic antibiotics. METHODS: An anonymous questionnaire was mailed to ophthalmologists in California, Florida, Illinois, and Missouri. The results were tabulated and analyzed statistically. RESULTS: Six hundred twenty-nine usable questionnaires (10.3%) were returned. In the management of corneal ulcers, 42.2% of comprehensive ophthalmologists and 75.3% of cornea specialists perform Gram stains some of the time. A total of 73.3% of comprehensive ophthalmologists and 93.7% of cornea specialists perform corneal cultures some of the time. A total of 88.8% of comprehensive ophthalmologists and 76% of cornea specialists initiate treatment with the newer fluoroquinolone antibiotics. A total of 12.1% of comprehensive ophthalmologists and 41% of cornea specialists would select fortified antibiotics for the treatment of corneal ulcers. The percentage of those who feel that fortified antibiotics are superior ranges from 17.7% for comprehensive ophthalmologists to 33.3% for cornea specialists. A total of 65.7% of comprehensive ophthalmologists indicate that the newer fluoroquinolones have impacted their practices, and 58.3% indicate that they represent an improvement over older fluoroquinolones. CONCLUSIONS: Most responding ophthalmologists initiate empiric therapy with the newer fluoroquinolone antibiotics for corneal ulcers, forgoing Gram staining and culturing. However, respondents are not universally sanguine about the newer fluoroquinolones. The practice patterns and opinions on antibiotics differ almost universally between comprehensive ophthalmologists and cornea specialists. Larger, more detailed surveys and more specific analyses would help to further establish the factors that lead to differing management choices and opinions.

Optical coherence tomography of clear corneal incisions for cataract surgery.

PURPOSE: To study the architecture of clear corneal incisions for phacoemulsification cataract surgery using optical coherence tomography (OCT). SETTING: Doheny Eye Institute and Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA. METHODS: This prospective study comprised 20 eyes of 20 patients 1 month after cataract surgery performed by 1 of 2 experienced surgeons. Temporal clear corneal single-plane incisions were made with 3.0 mm metal keratomes. Each eye was scanned before and 1 month after surgery with a prototype high-speed anterior segment OCT system (Carl Zeiss Meditec, Inc.). The OCT scans were repeated 3 times during the same visit. The length of the corneal incision, thickness of the cornea, and position of the incision (distance from external wound edge to scleral spur) were measured using a computer caliper. The angle of the incision relative to the corneal surface was then calculated. RESULTS: The mean corneal incision length was 1.81 mm +/- 0.27 (SD), the mean corneal thickness at the incision was 747 +/- 67 microm, and the mean distance between the incision and the scleral spur was 1.46 +/- 0.24 mm. The mean angle of the incision was 26.8 +/- 5.5 degrees. The measurements were repeatable to within +/-0.072 mm (pooled standard deviation) for the incision length, +/-11 microm for the corneal thickness, and +/-0.042 mm for the position of the incision. CONCLUSIONS: Optical coherence tomography allowed excellent evaluation of corneal incisions in cataract surgery postoperatively. Measurements of wound dimensions using OCT were highly repeatable.

High-speed optical coherence tomography for management after laser in situ keratomileusis.

PURPOSE: To report applications of optical coherence tomography (OCT) in the management of laser in situ keratomileusis (LASIK) related problems. SETTING: Doheny Eye Institute and Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA. METHODS: Five patients referred for LASIK-related problems were enrolled in a prospective observational study. Clinical examination, ultrasound (US) pachymetry, Placido ring slit-scanning corneal topography (Orbscan II, Bausch & Lomb), and high-speed corneal OCT were performed. RESULTS: In cases of regression and keratectasia, OCT provided thickness measurements of the cornea, flap, and posterior stromal bed. Locations of tissue loss and flap interface planes were identified in a case with a recut enhancement complication. The information was used to determine whether further laser ablation was safe, confirm keratectasia, and manage complications. Optical coherence tomography measurements of central corneal thickness agreed well with US pachymetry measurements (difference 6.4 microm +/- 11.7 [SD]) (P = .026), while Orbscan significantly underestimated corneal thickness (-67.5 +/- 72.5 microm) (P = .17). CONCLUSIONS: High-speed OCT provided noncontact imaging and measurement of LASIK anatomy. It was useful in monitoring LASIK results and evaluating complications.

Optical coherence tomography to assess intrastromal corneal ring segment depth in keratoconic eyes.

PURPOSE: To investigate intrastromal corneal ring segment depth with a high-speed corneal optical coherence tomography (OCT) system. SETTING: Doheny Eye Institute, University of Southern California, Los Angeles, California, USA. METHODS: A prospective observational case series comprised 4 eyes of 4 patients receiving Intacs intrastromal corneal ring segments (Addition Technology, Inc.) for keratoconus. Optical coherence tomography (OCT) was performed between 7 days and 43 days after implantation. RESULTS: The slitlamp impression of intrastromal corneal ring segment implantation depth did not correlate well with OCT measurements (r(2) = 0.68). The fractional implantation depth was correlated with several surgical variables using a stepwise multivariate regression model, and 2 statistically significant correlations were found. The position of the distal portions of the ring segments was shallower than that of the portion closer to the insertion site (P = .003). Segments placed in the inferior cornea (P = .008) experienced more distal shallowing. Shallower depth was associated with greater fractional anterior stromal compression (P = .04). CONCLUSIONS: Shallower placement of intrastromal corneal ring segments may result in more complications, such as epithelial-stromal breakdown and extrusion, because of the greater anterior stromal tensile strain. The distal and inferior portions of intrastromal corneal ring segments tended to be placed at a shallower depth. Optical coherence tomography provided precise measurement of ring segment depth and may help identify implants that pose a greater risk for depth-related complications.