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PURPOSE: The aim of this study was to assess and compare the association of glaucoma therapy with graft survival after performing penetrating keratoplasty (PKP) and Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: A retrospective chart review was performed of cases: primary PKP from January 1, 2003, to December 31, 2005, or primary DSAEK from January 1, 2006, to December 31, 2008. Eyes with a surgical indication of pseudophakic corneal edema were included in the statistical analysis. Eyes were stratified by glaucoma treatment into those with (1) no glaucoma treatment, (2) medical therapy only, or (3) surgical intervention. The main outcome measure was graft survival. RESULTS: Fifty-seven PKP-operated and 156 DSAEK-operated eyes met the inclusion criteria. After PKP and DSAEK, respectively, the 5-year Kaplan-Meier graft survival was 94.7% and 93.8% in eyes with no glaucoma treatment (P > 0.99), 93.8% and 96.3% in eyes with medical therapy only (P > 0.99), and 56.8% and 50% in eyes with surgical intervention (P > 0.99). After both procedures were performed, graft survival was significantly worse in eyes with surgical intervention compared with that in eyes with no glaucoma treatment (P < 0.0001) or in eyes with medical therapy alone (P < 0.0001). CONCLUSIONS: PKP and DSAEK have comparable graft survival in eyes without glaucoma management and in those with comparable glaucoma management.

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PURPOSE: To compare the performance on the EYESi surgical simulator capsulorhexis training module between medical students and residents and experienced cataract surgeons. SETTING: Department of Ophthalmology, University of Iowa, Iowa City, Iowa, USA. DESIGN: Comparative case series. METHODS: The study comprised medical students and residents at the University of Iowa and experienced cataract surgeons. Neither group had experience with the simulator. Each participant completed 4 trials on the capsulorhexis module. RESULTS: The 7 experienced surgeons achieved statistically significantly better total scores than the 16 medical students and residents on the easy level and the medium level of the capsulorhexis module (P = .004 and P = .000007, respectively). Experienced surgeons achieved significantly better scores in all parameters at the medium level, with better centering (P = .001), less corneal injury (P = .02), fewer spikes (P = .03), less time operating without a red reflex (P = .0005), better roundness of the capsulorhexis (P = .003), and less time completing tasks (P = .008). CONCLUSION: The surgical simulator capsulorhexis module showed significant construct validity (P<.05).

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PURPOSE: To determine the prevalence and risk factors for escalation of glaucoma therapy after deep lamellar endothelial keratoplasty (DLEK). METHODS: Retrospective review of every case of DLEK performed at a tertiary care facility between December 1, 2003 and January 31, 2006. RESULTS: Eighty eyes met the inclusion criteria. Escalation of glaucoma therapy occurred in 13 eyes (16.3%) during a mean follow-up period of 27.1 months. Ten eyes required additional topical medical therapy, and 3 eyes required surgical intervention. Glaucoma therapy escalation was significantly associated with preexisting glaucoma (42.9% vs. 10.6%; P = 0.008). CONCLUSION: Escalation of glaucoma therapy is not uncommon after DLEK, especially in eyes with preexisting glaucoma.

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PURPOSE: To determine whether institution of a structured surgical curriculum for ophthalmology residents decreased the rate of sentinel surgical complications. SETTING: Veterans Affairs Medical Center, Des Moines, Iowa, USA. METHODS: A retrospective review was performed of third-year ophthalmic resident quality-assurance surgical outcomes data at a single residency-training site from 1998 to 2008. The primary outcome measure was defined as a sentinel event; that is, a posterior capsule tear (with or without vitreous loss) or vitreous loss (from any cause) occurring during a resident-performed case. The study population was divided into 2 groups. Group 1 comprised surgical cases of residents trained before the surgical curriculum change (academic years 1998 to 2003) and Group 2, surgical cases of residents trained with the enhanced curriculum (academic years 2004 to 2008). Data from 1 year (academic year 2003 to 2004) were excluded because the transition to the enhanced curriculum occurred during that period. The data were analyzed and adjusted for surgical experience. RESULTS: In Group 1 (before institution of surgical curriculum), there were 823 cases with 59 sentinel complications. In Group 2 (after institution of surgical curriculum), there were 1009 cases with 38 sentinel complications. There was a statistically significant reduction in the sentinel complication rate, from 7.17% before the curriculum changes to 3.77% with the enhanced curriculum (P = .001, unpaired 2-tailed t test). CONCLUSION: Implementation of a structured surgical curriculum resulted in a statistically significant reduction in sentinel event complications, even after adjusting for surgical experience.

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PURPOSE: To evaluate the performance of an automated algorithm for determination of the cup and rim from close-to-isotropic spectral domain (SD) OCT images of the optic nerve head (ONH) and compare to the cup and rim as determined by glaucoma experts from stereo color photographs of the same eye. METHODS: Thirty-four consecutive patients with glaucoma were included in the study, and the ONH in the left eye was imaged with SD-OCT and stereo color photography on the same day. The cup and rim were segmented in all ONH OCT volumes by a novel voxel column classification algorithm, and linear cup-to-disc (c/d) ratio was determined. Three fellowship-trained glaucoma specialists performed planimetry on the stereo color photographs, and c/d was also determined. The primary outcome measure was the correlation between algorithm-determined c/d and planimetry-derived c/d. RESULTS: The correlation of algorithm c/d to experts 1, 2, and 3 was 0.90, 0.87, and 0.93, respectively. The c/d correlation of expert 1 to 2, 1 to 3, and 2 to 3, were 0.89, 0.93, and 0.88, respectively. CONCLUSIONS: In this preliminary study, we have developed a novel algorithm to determine the cup and rim in close-to-isotropic SD-OCT images of the ONH and have shown that its performance for determination of the cup and rim from SD-OCT images is similar to that of planimetry by glaucoma experts. Validation on a larger glaucoma sample as well as normal controls is warranted.

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OBJECTIVE: To determine and compare variance components in linear cup-to-disc ratio (LCDR) estimates by computer-assisted planimetry by human experts, and automated machine algorithm (digital automated planimetry). DESIGN: Prospective case series for evaluation of planimetry. PARTICIPANTS: Forty-four eyes of 44 consecutive patients from the outpatient Glaucoma Service at University of Iowa with diagnosis of glaucoma or glaucoma suspect were studied. METHODS: Six stereo pairs of optic nerve photographs were taken per eye: 3 repeat stereo pairs using simultaneous fixed-stereo base fundus camera (Nidek 3Dx) and another 3 repeat stereo pairs using sequential variable-stereo base fundus camera (Zeiss). Each optic disc stereo pair was digitized and segmented into cup and rim by 3 glaucoma specialists (computer-assisted planimetry) and using a computer algorithm (digital automated planimetry), and LCDR was calculated for each segmentation (either specialist or algorithm). A linear mixed model was used to estimate mean, SD, and variance components of measurements. MAIN OUTCOME MEASURES: Average LCDR, interobserver, interrepeat, intercamera coefficients of variation (CV) of LCDR and their 95% tolerance limits. RESULTS: There was a significant difference in LCDR estimates among the 3 glaucoma specialists. The interobserver CV of 10.65% was larger than interrepeat (6.7%) or intercamera CV (7.6%). For the algorithm, the LCDR estimate was significantly higher for simultaneous stereo fundus images (Nidek, mean: 0.66) than for sequential stereo fundus images (Zeiss, mean: 0.64), whereas interrepeat CV for Nidek (4.4%) was lower than Zeiss (6.36%); the algorithm's interrepeat and intercamera CV were 5.47% and 7.26%, respectively. CONCLUSIONS: Interobserver variability was the largest source of variation for glaucoma specialists, whereas their interrepeat and intercamera variability is comparable with that of the algorithm. DAP reduces variability on LCDR estimates from simultaneous stereo images, such as the Nidek 3Dx.

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Glaucoma after penetrating keratoplasty is a frequently observed post-operative complication and is a risk factor for graft failure. Penetrating keratoplasty performed for aphakic and pseudophakic bullous keratopathy and inflammatory conditions are more likely to cause postoperative glaucoma compared with keratoconus and Fuchs' endothelial dystrophy. The intraocular pressure elevation may occur immediately after surgery or in the early to late postoperative period. Early postoperative causes of glaucoma include pre-existing glaucoma, retained viscoelastic, hyphema, inflammation, pupillary block, aqueous misdirection, or suprachoroidal hemorrhage. Late causes include pre-existing glaucoma, angle-closure glaucoma, ghost cell glaucoma, suprachoroidal hemorrhage, and steroid-induced glaucoma. Determining the cause of IOP elevation can help guide therapeutic intervention. Treatments for refractory glaucoma include topical anti-glaucoma medications such as beta-adrenergic blockers. Topical carbonic anhydrase inhibitors, miotic agents, adrenergic agonists, and prostaglandin analogs should be used with caution in the post-keratoplasty patient, because of the possibility of corneal decompensation, cystoid macular edema, or persistent inflammation. Various glaucoma surgical treatments have reported success in post-keratoplasty glaucoma. Trabeculectomy with mitomycin C can be successful in controlling IOP without the corneal toxicity noted with 5-fluorouracil. Glaucoma drainage devices have successfully controlled intraocular pressure in postkeratoplasty glaucoma; this is, however, associated with increased risk of graft failure. Placement of the tube through the pars plana may improve graft success compared with implantation within the anterior chamber. In addition, cyclophotocoagulation remains a useful procedure for eyes that have refractory glaucoma despite multiple surgical interventions.

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The current resident selection process for ophthalmology has undergone little change over the last several years and remains highly dependent on the traditional selection factors (i.e., grades, honors, letters of recommendation, and an interview). Unfortunately, these selection factors have not been shown to be consistently predictive of future resident performance. In addition, the Accreditation Council for Graduate Medical Education (ACGME) has mandated implementation of six new competencies in resident training in the USA and the current selection process does not directly recruit for these competencies. We propose an implementation strategy to re-engineer and improve the resident selection process in ophthalmology and potentially develop assessments that would be predictive of actual downstream resident performance that would encompass the ACGME related competencies. An intra-departmental Task Force for the ACGME Competencies reviewed a PubMed literature search regarding resident selection. A content expert (AGL) gleaned selected "good practices" from the literature review and summarized the results. Specific recommendations were reviewed for topicality to ophthalmology and where possible for feasibility, reliability, and validity. We summarize several good practices identified from the literature review and propose an implementation matrix for aligning the resident application process with the ACGME competencies that might include: using a standardized and consolidated academic score for the cognitive domains; converting the letter of recommendation format into a letter of evaluation; standardizing the letters of evaluation, including the "Dean's letter"; using behavior specific interview techniques with standardized questions; and developing a specialty based consensus for the selection of traits specific to ophthalmology that might predict success. The resident selection process for ophthalmology might be improved by implementation of specific good practices from the literature. Ophthalmology should strive to develop applicant selection tools that might be useful for predicting residency performance and that would align with the ACGME competency mandate for tools to predict future performance as a physician.

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The Accreditation Council for Graduate Medical Education (ACGME) has mandated that residency programs, including ophthalmology, teach and assess specific competencies, including systems-based learning. We review the pertinent literature on systems-based learning for ophthalmology and recommend specific "good practices" to manage the ACGME mandate. Tools are required that both teach and assess systems based learning competency simultaneously, that are reliable and valid, that have low faculty burden, and that are affordable, practical, and fair. Future research should provide evidence that these interventions produce improved educational and patient outcomes and show proof of competence in systems based learning among residents and clinicians in practice.

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PURPOSE: To study the concordance of diurnal intraocular pressure (IOP) between fellow eyes in primary open-angle glaucoma (POAG). DESIGN: Retrospective chart review. PARTICIPANTS: Ninety-three POAG patients. METHODS: Patients who met the definition of POAG and underwent diurnal curve measurement were included. Subjects were excluded if there was a history of surgery, trauma, ocular vascular disease, incomplete diurnal curve, or asymmetric ocular medication use. Patients on symmetric ocular medication were included and analyzed separately. Goldmann applanation tonometry was performed at 10 am, 1 pm, 4 pm, 7 pm, 10 pm, and 7 am (the next day). The following statistical analyses were performed: (1) average Pearson correlation coefficient (r) from individual correlations of right and left eye IOP over the 6 time points for each subject; (2) linear mixed model analysis for repeated measures, with eye (right and left) and time as the within-subject fixed effects, and (3) absolute difference in change in IOP between fellow eyes over each time interval and probability that the difference was within 2 or 3 mmHg. MAIN OUTCOME MEASURE: The concordance of the IOP between fellow eyes as measured by absolute difference in change in IOP between fellow eyes and probability of the difference being within 2 or 3 mmHg. RESULTS: Thirty-seven patients were untreated and 56 were treated on symmetric IOP-lowering medications. The diurnal curves of fellow eyes exhibited parallel profiles according to the linear mixed model. The average difference in the change of IOP between fellow eyes over given time intervals ranged from 1.6 to 2.0 mmHg. The estimated probability that the absolute change in IOP between fellow eyes was within 2 mmHg was 68% to 90%, and within 3 mmHg was 78% to 95% for all time intervals. CONCLUSION: The diurnal variation of IOP in POAG is largely concordant between fellow eyes. For any given time interval, the fellow eye IOPs may fluctuate asymmetrically a minority of the time. Clinicians who utilize the uniocular trial should be aware of the limit of the IOP concordance.

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PURPOSE: To describe an ophthalmology wet laboratory (OWL) curriculum for residents in training. METHODS: Systematic literature review and selection of best practices for use in the OWL learning plan from a single academic ophthalmology program. RESULTS: A pretest and posttest of cognitive skills, objective wet laboratory structured assessment of skill and technique, and summative global evaluation form were developed as part of a systematic OWL curriculum. CONCLUSION: The Iowa OWL curriculum may form the basis for successfully utilizing the wet laboratory to teach and assess aspects of resident surgical competence in cataract surgery.

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PURPOSE: The study objective was to determine the concordance of intraocular pressure (IOP) in glaucoma suspects (GS) and normal tension glaucoma (NTG) patients. METHODS: This was a retrospective review of diurnal curves of untreated GS and NTG patients. No subject had IOP greater than 21 mm Hg. We defined GS patients as having suspicious optic nerves with normal visual fields, and NTG patients as having glaucomatous optic nerves with associated visual field loss. Goldmann applanation tonometry was performed at 10:00, 13:00, 16:00, 19:00, 22:00, and 07:00. Linear association of OD and OS IOP was estimated using Pearson correlation coefficient (r). The diurnal period was divided into 7 time intervals of 3, 6, 9, 12, 15, 18, and 21 hours, and the absolute difference in change in IOP between fellow eyes and probability that it was within 3 mm Hg were calculated. RESULTS: The study included 68 GS and 95 NTG subjects. The diurnal curves of the OD and OS showed a parallel course in both groups. The average correlations (r) of OD and OS IOP over the 6 time points were 0.78 and 0.81 for GS and NTG, respectively. The mean absolute difference in IOP change between OD and OS over the 6 time intervals ranged between 1.4 and 1.9 mm Hg for GS, and 1.3 and 1.5 mm Hg for NTG subjects. The probability that this difference was within 3 mm Hg ranged between 87% and 94% for GS, and 86% and 93% for NTG subjects. CONCLUSIONS: The diurnal variation in IOP between the 2 eyes in GS and NTG is largely concordant in approximately 90% of the time.

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PURPOSE: To evaluate a novel automated segmentation algorithm for cup-to-disc segmentation from stereo color photographs of patients with glaucoma for the measurement of glaucoma progression. METHODS: Stereo color photographs of the optic disc were obtained by using a fixed stereo-base fundus camera in 58 eyes of 58 patients with suspected or open-angle glaucoma. Manual planimetry was performed by three glaucoma faculty members to delineate a reference standard rim and cup segmentation of all stereo pairs and by three glaucoma fellows as well. Pixel feature classification was evaluated on the stereo pairs and corresponding reference standard, by using feature computation based on simulation of photoreceptor color opponency and visual cortex simple and complex cells. An optimal subset of 12 features was used to segment all pixels in all stereo pairs, and the percentage of pixels assigned the correct class and linear cup-to-disc ratio (LCDR) estimates of the glaucoma fellows and the algorithm were compared to the reference standard. RESULTS: The algorithm was able to assign cup, rim, and background correctly to 88% of all pixels. Correlations of the LCDR estimates of glaucoma fellows with those of the reference standard were 0.73 (95% CI, 0.58-0.83), 0.81 (95% CI, 0.70-0.89), and 0.86 (95% CI, 0.78-0.91), respectively, whereas the correlation of the algorithm with the reference standard was 0.93 (95% CI, 0.89-0.96; n = 58). CONCLUSIONS: The pixel feature classification algorithm allows objective segmentation of the optic disc from conventional color stereo photographs automatically without human input. The performance of the disc segmentation and LCDR calculation of the algorithm was comparable to that of glaucoma fellows in training and is promising for objective evaluation of optic disc cupping.

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