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Objective: The Eye Institute of Alberta Emergency Eye Clinic (EIA EEC) is a tertiary eye care centre that provides emergency eye services to a population of more than 1 million. The purpose of this study was to describe the epidemiology of ocular emergencies at the EIA EEC., Design: Prospective epidemiologic study based on secondary use of patient data., Participants: All patients seen in the EIA EEC on weekdays between July 2020 and June 2021., Methods: Charts were reviewed to obtain patient demographics, referral details, final diagnoses, need for imaging, emergency procedures, or further referrals. SPSS Statistics was used for data analysis., Results: A total of 2586 patients were seen over the study period. Most of the referrals (58%) were from emergency physicians. Optometrists and general physicians contributed 14% and 11% of referrals, respectively. Most referral diagnoses were related to inflammation (32%), and trauma (22%). Of all the cases of inflammation, 41% involved infection of the eye and 8% involved infection of ocular adnexa. In addition, 44% and 7% of cases involved noninfectious inflammation of the eye and adnexa, respectively. Frequently preformed emergency procedures were corneal or conjunctival foreign-body removal (39%) and corneal scraping (14%)., Conclusions: Continuing education related to emergency eye care may be most beneficial to emergency physicians, general practitioners, and optometrists. Educational opportunities could focus on most frequently seen diagnostic categories such as inflammation and trauma. Targeted public education aimed at preventing ocular trauma and infection, such as promoting wearing eye protection and practicing contact lens hygiene, may be beneficial., (Copyright © 2023 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To create a standardized undergraduate medicine ophthalmology curriculum for Canadian medical schools., Design: Two-stage modified Delphi technique., Participants: Undergraduate ophthalmology leads at all the medical schools in Canada and 6 nonophthalmologist physicians with medical education expertise., Methods: In stage 1, a preliminary list of curricular objectives was developed using the 2018 Association of University Professors in Ophthalmology's list of curricular objectives as a foundation. Subsequently, an online survey was sent to 24 individuals (18 ophthalmology undergraduate curriculum leads and 6 non-ophthalmology medical educators) at 17 institutions to evaluate the objectives using a 5-point Likert-type scale. In stage 2, the ophthalmology curriculum leads were invited to participate in a virtual meeting during which the list of curricular objectives was discussed and finalized by consensus., Results: In stage 1, a preliminary list of 76 learning objectives organized into 10 overarching topics was developed. A total of 21 survey responses were received (87.5% response rate), allowing for the creation of a revised list. In stage 2, five participants from four schools met, achieving consensus following one round of feedback. The final undergraduate ophthalmology curriculum contained 10 topics and 75 objectives; it covered common presentations of a variety of acute and chronic eye diseases that were felt to be relevant to a wide medical audience., Conclusions: The consensus obtained on a comprehensive list of undergraduate medicine ophthalmology curricular objectives identified in this study is the first of its kind in Canada. These objectives can be used by medical schools across Canada to standardize undergraduate ophthalmology teaching., (Copyright © 2023 Canadian Ophthalmological Society. All rights reserved.)

Objective: Lengthy wait times for cataract surgery can negatively affect patients' quality of life and increase the incidence of falls and depression. The COVID-19 pandemic has presented significant challenges to the delivery of elective cataract surgeries. The effects of the COVID-19 pandemic on cataract surgery wait times in the Alberta Health Services' Edmonton zone were studied by examining the wait times before and during the pandemic., Methods: This study was conducted based on a retrospective population-based design. Data were compiled from a centralized database related to hospital-based cataract surgery (Royal Alexandra, Fort Saskatchewan, and WestView Health Centre) between April 2019 and March 2022 (i.e., 3 fiscal years)., Results: The average wait time for cataract surgery increased from 14.4 ± 1.4 weeks in 2019-2020 to 18.2 ± 2.7 weeks in 2020-2021 (p = 0.005) and then decreased to 11.5 ± 1.3 in 2021-2022 (p < 0.001). The number of completed surgeries decreased from 13,103 in 2019-200 to 9,308 (p = 0.09) and 10,365 (p = 0.1) during the next 2 years. The annual operating room time for scheduled cases was reduced to 4463 hours (p = 0.42) and 4552 hours (p = 0.15) during the pandemic compared with 5541 hours before the pandemic. However, the average waitlist size decreased from 6629 at the end of 2019-200 to 6122 (p = 0.029) and 4011 (p < 0.001) during the next 2 years., Conclusion: The COVID-19 pandemic resulted in significantly increased average wait times for elective cataract surgery during the first year of the pandemic. Because of a reduction of the waitlist size, the wait times decreased during the second year of the pandemic., (Copyright © 2022 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To compare costs between two different eye drop delivery modalities: multidose bottles and single-use minims., Design: Retrospective cohort study., Methods: Monthly dilating eye drop costs and quantities (tropicamide 1%, phenylephrine 2.5%, cyclopentolate 1%) were studied over a 2-year period between April 2013 and March 2015 at 2 tertiary ophthalmic centres (Royal Alexandra Hospital [RAH, Edmonton] and Rockyview General Hospital [RGH, Calgary]). In April 2014, RAH switched its dilating eye drop practice from predominantly multidose bottles to single-use minims, whereas RGH continued using predominantly multidose bottles. Eye drop volume and total and per-patient eye drop costs were quantified at RAH before switching (pre-intervention) and after (post-intervention) using an interrupted time-series analysis with RGH as a control. A counterfactual analysis was also performed. Significance was obtained using independent t-testing., Results: After switching to single-use minims, RAH experienced changes in the following: an increase in single-use minims as a proportion of total eye drop utilization (from 5.6% to 89.1%; p = 0.001), an increase in total eye drop cost by $2117 per month (95% confidence interval [CI], $1354-$2880; p < 0.001), an increase in per-patient costs by $984 per 1000 patients per month (95% CI, $674-$1293). Contrastingly, RGH did not experience similar changes. Ultimately, the cost of switching to single-use minims was $22 481 (95% CI, $7830-$31 336) over a 12-month period., Conclusions: If safe eye drop practices are enforced via proper protocols, the use of multidose bottles may be a more cost-effective option than single-use minims for routine clinical practice., (Copyright © 2021 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To determine the incidence and risk factors for steroid response in patients undergoing combined phacoemulsification cataract extraction (PCE) and microinvasive glaucoma surgery with either trabecular microbypass stent implantation (iStent) or ab interno trabeculectomy (Trabectome)., Design: Retrospective, noncomparative, single-institutional observational chart review., Participants: Consecutive patients with open-angle glaucoma who underwent PCE with iStent or Trabectome with 3 months of follow-up., Methods: Data were collected from patient charts, including pre- and postoperative intraocular pressure (IOP) following application of topical corticosteroid on postoperative visits for at least 3 months. A steroid response was defined as an IOP rise of greater than 5 mm Hg beginning at least 3 days after surgery with no other obvious explanation and with IOP < 20 mm Hg following rapid tapering or withdrawal of the steroid., Results: A total of 118 eyes from 89 patients, average age of 71.4 ±12.1 years, were included. Overall, a steroid response was seen in 12.7% of eyes (n = 15), and no difference was noted between Trabectome (11.8%) and iStent (13.6%, p = 0.782) eyes. Axial length (AL; p = 0.01), younger age (p = 0.009), traumatic glaucoma (p = 0.004), and normal-tension glaucoma (NTG; p = 0.0048) were significant predictors of steroid response in a multivariate analysis. In eyes with AL ≥ 25 mm, the steroid response rate was 40%, in contrast to eyes with AL < 25 mm, where it was 10.2%., Conclusion: A steroid response develops in approximately 1 in 8 patients undergoing PCE with Trabectome or iStent. Young age, AL > 25 mm, traumatic glaucoma, and NTG were found to be significant predictors of steroid response., (Copyright © 2021 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To describe a teaching model for aqueous tube shunt surgery using freshly enucleated pig eyes., Design: A descriptive methods report, containing a small prospective noncomparative interventional case series., Participants: Six ophthalmology residents from the University of Alberta program., Methods: A descriptive report outlines the materials and methods required for creating a surgical wet lab that teaches aqueous draining device implantation. Residents practiced each step associated with the insertion of plated aqueous tube shunt devices in porcine eyes., Results: The porcine model worked well to demonstrate and perform steps associated with tube implant surgery. Trainee comfort improved in all surgical steps practiced during the session when reassessed at 3-month follow-up: priming and anchoring the drainage device (p = 0.042), inserting the tube into the eye (p = 0.025), creating and securing a scleral patch graft (p = 0.034), and closure of the conjunctiva (p = 0.034). Overall confidence in performing tube shunt surgery also remained above baseline at follow-up (p = 0.042)., Conclusions: Implantation of tube shunt devices in the porcine model closely resembles surgery in human eyes. Practicing each step associated with tube shunt surgery on porcine eyes in a supervised wet-lab environment improves trainee confidence in the procedure., (Copyright © 2019 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate preoperative testing for cataract surgery, implement stakeholder-driven change, and increase the number of patients who arrived for surgery with complete preoperative requirements, for the purpose of delivering safe, high-quality, and cost-effective care for patients., Design: Quality improvement., Participants: Cataract surgery patients, health care staff in Ophthalmology Day Surgery, an Ophthalmology improvement team, the Clinical Section Heads of Ophthalmology and Anaesthesia, Quality Consultants, and members of the Quality Council participated in this study., Methods: A lean quality improvement approach was used to define and build understanding of the problem. Between July and November 2016, a chart-based reporting system captured all patients who arrived for cataract surgery with expired or incomplete preoperative requirements. A cost analysis was completed, and evidence was reviewed to ensure alignment with best practice preoperative recommendations., Results: On average, 25% (619/2451 over a 17-week period) of patients per day arrived at the Ophthalmology Day Surgery for cataract surgery with incomplete and/or expired physical history forms and ECGs. An improvement team worked to implement a radical improvement idea and relied on an existing questionnaire to ensure patient safety preoperatively., Conclusions: Based on the literature, best practice guidelines, and a cost analysis, it was decided that patients undergoing routine cataract surgery in Edmonton Zone Hospitals under regional anaesthesia would no longer require physician history and physicals and ECGs. Elimination of the preoperative requirements for all but select high-risk patients meant that 100% of patients who arrived for cataract surgery would not have outstanding presurgery requirements., (Copyright © 2018 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Purpose: The effectiveness of selective laser trabeculoplasty (SLT) was compared with argon laser trabeculoplasty (ALT) in a randomized clinical trial for patients with medically uncontrolled open-angle glaucoma who have previously received 360° SLT., Design: An active equivalence parallel armed randomized control trial., Participants: Patients with open-angle glaucoma including pigmentary dispersion syndrome and pseudoexfoliation syndrome were enrolled into the study from 7 different sites across Canada., Methods: One setting of 180° of either SLT or ALT was assigned randomly and applied to each participant., Main Outcome Measures: The change in intraocular pressure (IOP) from baseline to 12 months was compared between the 2 groups., Results: A total of 132 patients were recruited, 2 of which dropped out early in the study, leaving 130 patients who completed the study as per protocol. For those, the study's primary outcome was calculated. The IOP change at 1 year in comparison to baseline for SLT vs. ALT was found to be different by 0.33 mmHg between the 2 groups (3.16 for SLT and 2.83 for ALT) and was not statistically significant (P = 0.71) Further analysis, though, showed that SLT had a significantly lower IOP reduction at early time points: 1 week and 1 month, but this effect was lost by 3 months. Corresponding to this finding was the strong trend for ALT to fail more quickly than SLT. Although repeatable, the first repeat SLT reduced IOP to only about half compared with initial SLT treatment., Conclusions: The comparison at 12 months following the laser therapy showed that both modalities lowered the IOP with approximately 3 mmHg, yet essentially all of the time-to-failure analyses favored SLT over ALT. The repeat SLT effect was found to be half of the initial treatment., (Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.)

Objective: To compare the efficacy and safety of ab interno trabeculectomy with the Trabectome combined with cataract surgery (phaco-AIT) versus Trabeculectomy with mitomycin C combined with cataract surgery (phaco-Trab) in open-angle glaucoma., Methods: A prospective randomized controlled trial with a single surgeon and surgical center was undertaken. Patients were recruited from July 2009 to October 2014. Primary outcomes were mean intraocular pressure (IOP) at 6 months and surgical complications. Secondary outcomes were mean IOP at 12 months, achievement of target IOP, number of glaucoma medications, and rate of secondary surgery., Results: The trial was ended early before achieving our intended sample size due to difficulties in recruitment and lack of clinical equipoise over time. Nineteen patients were enrolled, 10 phaco-AIT and 9 phaco-Trab. Baseline IOP was 20.0 ± 5.3 in phaco-AIT and 23.1 ± 6.4 mm Hg in phaco-Trab (p = 0.22). IOP decreased to 17.5 ± 3.8 and 16.0 ± 6.0 mm Hg at 6 months (p = 0.54), and 16.8 ± 2.7 and 17.1 ± 5.0 mm Hg at 1 year (p = 0.57), respectively. Mean number of glaucoma medications at baseline was 1.8 ± 1.3 in phaco-AIT and 1.4 ± 1.1 in phaco-Trab (p = 0.59). Mean number of glaucoma medications decreased to 0.78 ± 1.39 and 0.38 ± 0.74 at 6 months (p = 0.68), and 0.44 ± 0.88 and 0.75 ± 0.89 at 1 year (p = 0.41), respectively. Mild and moderate complications were seen in both treatment groups, but severe complications were seen only in phaco-Trab. One secondary glaucoma procedure was required in the phaco-AIT group., Conclusions: Phaco-AIT achieved similar IOP lowering at 6 and 12 months compared with phaco-Trab with a similar number of glaucoma medications required at 1 year, and no serious complications were identified in the Phaco-AIT group., (Copyright © 2018 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To determine the efficacy and safety of ab interno trabeculectomy with Trabectome in juvenile open-angle glaucoma (JOAG) patients., Design: Prospective cohort study., Methods: Evaluation of the 12-month results of 2 patient groups receiving ab interno trabeculectomy: group 1, eyes with no prior incisional surgery; group 2, eyes that had prior incisional cataract or glaucoma surgery., Results: Group 1, 40 eyes (average age 31 ± 7 years), had a significant reduction in intraocular pressure (IOP) of 10.6 mm Hg at 12 months from a baseline of 27.4 mm Hg (p = 0.01), and the number of glaucoma medications reduced by 0.4 (p = 0.80). Four eyes (10%) within the study period required a secondary glaucoma surgery. Group 2, 20 eyes (average age 27 ± 8 years), had a significant reduction in IOP of 8.8 mm Hg from a baseline of 27.1 mm Hg (p = 0.06), and the number of glaucoma medications reduced by 1.4 (p = 0.36). Five eyes (25%) from this group underwent a secondary glaucoma surgery within 12 months., Conclusion: After 1 year of follow-up, ab interno trabeculectomy appears to be an effective and safe intervention for patients with JOAG; however, a reduction in use of topical medications may not be observed in those receiving ab interno trabeculectomy as a primary procedure., (Copyright © 2018 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To compare the intraocular pressure-lowering efficacy and complication rate of ab interno trabeculectomy with the Trabectome between African American (AA) and Caucasian patients with open-angle glaucoma., Methods: A total of 164 patients (82 AA and 82 Caucasian) who underwent ab interno trabeculectomy over an 8-year period were included in this prospective, case-control study. The Neomedix database was used to look for AA or Caucasian patients with open-angle glaucoma who underwent Trabectome with or without phacoemulsification., Results: The average IOP of AA patients was reduced from 21.2 ± 6.8 mm Hg to 16.1 ± 4.1 mm Hg at 12 M (p < 0.01), and the mean number of glaucoma medications was reduced from 2.4 ± 1.3 to 2.0 ± 1.4 (p = 0.13). Among Caucasians, the mean IOP was reduced from 21.2 ± 6.8 mm Hg to 15.7 ± 4.2 mm Hg at 12 M (p < 0.01), and the number of medications dropped from 2.4 ± 1.2 to 1.7 ± 1.3 (p < 0.01). No statistically significant difference was found between these 2 race groups in IOP, number of medications, and complications. For complications with Trabectome alone, 13% of AA and 9% of Caucasian patients needed secondary surgery. There was only 1 case of hypotony which was in the AA group. For complications with Trabectome combined with phacoemulsification, 4% of AA as well as 4% of Caucasian patients required secondary surgery. There was only 1 case of hypotony which was in the Caucasian group., Conclusion: Ab interno trabeculectomy with Trabectome is associated with a reduction in IOP in both race groups with a similar complication and survival profiles., (Copyright © 2018 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: Pseudoexfoliation syndrome (PEX) is a systemic disease, but evidence of its association with cardiovascular disease (CVD) and cerebrovascular disease (CVA) is controversial. A quantitative systematic review will provide an accurate summary of the current body of the literature., Design: Meta-analysis., Participants: Not applicable., Methods: A comprehensive literature search of published and unpublished English-language studies was performed. Summary statistics were calculated using inverse variance weighting and are presented in forest plots. Sources of variance were evaluated statistically., Results: After screening 4547 studies, 47 articles were reviewed, and 25 eligible studies were selected that reported patients from around the world. Twenty studies enrolling 9583 individuals with PEX evaluated CVD, providing a summary odds ratio (OR) of 1.61 (95% CI 1.37-1.90). Eleven studies, enrolling 1308 PEX patients, evaluated CVA and generated a summary OR of 1.76 (1.40-2.22). For any vascular event (AVE) using all 25 studies, there were 9716 PEX patients and 363,312 control patients, yielding a summary OR of 1.64 (95% CI 1.39-1.92). Analysis for publication bias with the Egger's test was not significant for studies reporting CVD and AVE (p = 0.92 and 0.64, respectively) but was significant for CVA (p = 0.03). Asymmetry of Begg's funnel plot was noted for the CVA and AVE analyses. Multiple sensitivity analyses were performed, including assessment of study quality; the OR for all 3 outcomes varied minimally and remained significant in all analyses., Conclusion: There is strong evidence that PEX is significantly associated with both CVD and CVA., (Copyright © 2018 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To develop a standardized process for reviewing daily patient lists and identifying potential risks of misidentification. Our goal was to develop a proactive approach to identify and eliminate risks of patient misidentification., Methods: Assessment of current patient identification practices took place over a period of 4 weeks. Using a process map, a patient survey was developed to determine the encounter points when patient identification was confirmed. This information was used to develop a standardized protocol for review of daily appointment lists., Results: Review of daily appointment lists was completed to identify potential similar/same name risks. A standardized manual process of chart review, flagging, and tracking was developed., Conclusions: The name alert process resulted in a simple manual process for identifying which patients have a higher name risk and allowed care providers to take preventative action to decrease potential risk of incorrect diagnostic testing, procedure, or medication administration., (Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Background: Ophthalmology residents on call at the Royal Alexandra Hospital identified workplace disorganization and lack of standardization in emergency eye examination rooms as an impediment to efficient patient treatment., Objective: The aim of the study was to use the "6S Lean" model to improve workflow in eye examination rooms at the Royal Alexandra Hospital., Methods: With the assistance of quality improvement consultants, the "6S Lean" model was applied to the current operation of the emergency eye clinic examination rooms. This model, considering 8 waste categories, was then used to recommend and implement changes to the examination rooms and to workplace protocols to enhance efficiency and safety., Results: Eye examination rooms were improved with regards to setup, organization of supplies, inventory control, and maintenance. All targets were achieved, and the 5S audit checklist score increased by 33 points from 44 to 77., Conclusions: Implementation of the 6S methodology is a simple approach that removes inefficiencies from the workplace. The ophthalmology clinic removed waste from all 8 waste categories, increased audit results, mitigated patient and resident safety risks, and ultimately redirected resident time back to patient care delivery., (Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To investigate efficacy and safety of phaco-trabectome (PT) versus phaco-iStent (Pi) for intraocular pressure (IOP) control in open-angle glaucoma (OAG)., Design: Retrospective comparative case series., Participants: A total of 70 eyes of 55 patients with OAG underwent either PT surgery by a single surgeon or Pi (insertion of 2 stents) by another surgeon in Canada between January 2010 and December 2012., Methods: The medical records of consecutive adult patients who underwent either PT or Pi surgery were reviewed. All patients who satisfied both the inclusion and exclusion criteria were included in the outcomes analyses. IOP reduction, reduction in glaucoma medication, safety profile, and best-corrected visual acuity were evaluated., Results: Thirty-six eyes of 30 patients had PT and 34 eyes of 25 patients had Pi. Baseline IOP was higher in the PT group (20.92 ± 5.07 mm Hg) than in the Pi group (17.47 ± 4.87 mm Hg; p = 0.026). At 12 months there was no significant difference between groups in relative reduction of mean IOP (PT -5.09 ± 5.73, 24% relative reduction vs. Pi -3.84 ± 3.80, 22% relative reduction; p = 0.331) or glaucoma medication use (PT -0.49 ± 1.17 vs. Pi -0.26 ± 0.73; p = 0.168) from baseline. However, Pi had significantly fewer individual complications (PT 20 vs. Pi 5; p < 0.0001) throughout the postoperative period., Conclusion: At 12 months of follow-up, both techniques significantly lowered IOP, but fewer complications were observed in the Pi group., (Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: Wet labs are an important part of ophthalmology residency training in order to develop intraocular surgical proficiency. The purpose of this study was to compare the effectiveness of formalin versus microwave treatment to produce porcine cadaveric cataracts., Design: This study was a comparative observational study at a single centre., Methods: Cataracts were created through the injection of 0.1 mL of 100% ethanol into the anterior chamber followed by the infiltration of 0.1 mL of 37% formalin using a short 30-gauge needle into the lens by introduction through the pars plana. The comparison group investigated porcine eyes treated with a microwave for 5-13 seconds using a 700 W power setting. Two observers used a validated nuclear opalescence and corneal clarity scale to independently grade the treated eyes., Results: In total, 70 eyes were treated with either formalin or by microwave. The formalin eyes had an average lens opacity score of 0.04 ± 0.03 and 1.91 ± 01.10 pre- and post-treatment (p < 0.001). Microwaved eyes had an average pretreatment lens opacity of score 0.10 ± 0.31, which increased to 2.86 ± 0.1.08 post-treatment (p < 0.001). Post-treatment lens opacity was significantly greater in microwave eyes than in formalin-treated eyes (p = 0.003). Pretreatment corneal clarity was 3.65 ± 0.73 in the formalin group, and 3.70 ± 0.93 in the microwave group. After treatment, there was a significant reduction in corneal clarity within the formalin (3.01 ± 1.04, p = 0.0012) and microwave groups (3.03 ± 1.07, p < 0.001)., Conclusions: Porcine eye models provide a realistic way to simulate cataracts and so residents can practice the basics of cataract surgery. Both microwave and formalin-based treatments are able to opacify the porcine lens with acceptable reductions in corneal clarity., (Copyright © 2016 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

The optic nerve gray crescent can be of clinical significance if unrecognized during assessment for glaucoma. It has a characteristic appearance of a slate gray area of pigmentation within the disc margins and commonly appears along the inferotemporal or temporal neuroretinal rim areas. This type of disc rim pigmentation can create the impression of neuroretinal rim thinning, and thus lead to the misdiagnosis of glaucoma or "glaucoma suspect" with attendant implications for overtreatment or unnecessary close monitoring of such patients. The gray crescent is more common in African Americans than whites (prevalence rate 27% vs 7%) and is bilateral in at least 58% of cases. It has been reported in association with Kjer optic atrophy type 1. Suggested causes of the gray crescent include an accumulation of melanocytes, or retinal pigment epithelium cells partially located in the optic nerve head region if Bruch's membrane extends internal to the peripapillary scleral ring. Other causes of pigmentation that may resemble gray crescent are conus pigmentosus and variations of peripapillary atrophy. When a gray crescent is present, clinicians should endeavour to identify the true anatomical disc margins via the scleral lip and, if necessary, evaluate the patient further with imaging and visual field studies., (Copyright © 2014 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To review the diagnostic outcomes and clinical referral pathways of patients assessed and managed through a collaborative care patient-centred teleglaucoma program., Study Design: Retrospective cohort study., Methods: Eligible patients were those assessed by the referring optometrist or ophthalmologist to be open-angle glaucoma suspects or to have definite early open-angle glaucoma. A glaucoma specialist graded each case through virtual consultation. Clinical referral pathways were noted: in-person consultation with glaucoma specialist, repeat teleconsultation, collaborative glaucoma management with optometrist, or referral for nonglaucomatous ophthalmic pathology., Results: A total of 247 patients were referred to the program from 2008 to 2012. Of all teleconsults, 31.1% were diagnosed with glaucoma, 42.1% were suspects, and 26.7% were unaffected. Of all patients, 27% were referred for in-person glaucoma evaluation; 69% of patients could be managed by their referring optometrist, with 48% of patients requiring repeat teleconsultation. Treatment was initiated before being seen for 87% of patients with definite glaucoma and 28% of glaucoma suspects., Conclusions: Of all patients seen through the remote teleglaucoma program, most did not require an in-person consultation with an ophthalmologist and could be managed through distance collaboration. For the approximately one third who were diagnosed with glaucoma based on virtual assessment, medication was started in the majority of cases and in-person consultation was arranged. Further studies to validate and consider cost-effectiveness of this system are under way., (© 2013 Canadian Ophthalmological Society Published by Canadian Ophthalmological Society All rights reserved.)

Objective: To compare the efficacy of scanning laser ophthalmoscope microperimetry (SLO-MP) and Humphrey visual fields in detecting macular sensitivity changes in advanced glaucoma., Design: Prospective cohort study., Participants: 25 patients with advanced primary open angle glaucoma and 2 consecutive abnormal Humphrey 10-2 SITA Standard visual field tests., Methods: Thirty-six eyes of 25 patients with 2 consecutive abnormal Humphrey 10-2 SITA Standard (H10) visual fields were retested with a modified 10-2 SLO-MP within 3 months of the last reliable H10. A standardized grid was used to mark the macula. Primary outcome was change in mean macular sensitivity (dB; H10 and SLO-MP) in relation to mean macular retinal nerve fibre layer (RNFL) thickness (µm) by SLO- optical coherence tomography (SLO-OCT). Secondary outcome was comparison of reliability indices for both tests. Linear regression was used for analysis., Results: Mean macular sensitivity was significantly lower in SLO-MP (9.33 ± 3.37 dB) than H10 (18.83 ± 6.46 dB; p < 0.0001). Mean macular RNFL thickness correlated significantly with retinal sensitivity by both SLO-MP (r = 0.39, p < 0.02) and H10 (r = 0.37, p < 0.03). Fixation losses were better controlled in SLO-MP (0.38 ± 1.1) than H10 (4.28 ± 7.9; p = 0.008). False-positive responses were similar (SLO-MP: 2.25 ± 4.53, H10: 1.78 ± 3.33; p = 0.80). A statistically significant difference was noted in the false-negative responses (SLO-MP: 26.87 ± 25.24, H10: 5.33 ± 9.70; p < 0.0001)., Conclusions: Macular sensitivity determined by both H10 and SLO-MP correlates significantly with mean macular RNFL thickness measured by SLO-OCT. Precise localization of the macula in SLO-MP results in lower fixation losses. Detection of denser field defects by SLO-MP results in higher false-negative responses. A larger sample size is needed to further study the value of this diagnostic tool., (© 2013 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To describe ocular phenotypic features in Chinese families with primary angle closure (PAC)., Design: Prospective cohort study., Participants: 428 individuals of 103 eligible families., Methods: Probands identified in clinic and their relatives were examined. Measurements included intraocular pressure, anterior chamber depth, lens thickness, axial length, and gonioscopic features related to the anterior chamber angle. Electroretinogram (ERG) testing for dark and light adaptation on both eyes of each individual examined was also obtained., Results: There were 144 PAC affected patients (33.7%), 60 suspects (14%), and 224 unaffected individuals (52.3%). There were more than 2 affected members in 51 families (49.5%). Compared with unaffected individuals, affected individuals were more likely to be female, have shallower peripheral and central anterior chamber depths, narrower angles, thicker lenses, and shorter axial lengths (p<0.001). Affected patients and suspects had similar axial lengths (p>0.05). Compared with unaffected individuals, affected and suspect individuals showed ERG adaptation abnormalities (p<0.05). Of 45 unaffected individuals with mean axial length ≤ 22.00 mm (10.51%), 20 individuals (4.67%) showed ERG adaptation abnormalities similar to affected patients and suspects (p> 0.05)., Conclusions: Patients with PAC were significantly more likely to be female, have shorter axial length, and have thicker lenses compared with unaffected individuals. PAC suspects showed similar axial lengths to affected individuals. ERG abnormalities mainly occurred in affected patients and suspects, but also occurred in unaffected individuals with short axial length., (Copyright © 2013 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: Selective laser trabeculoplasty (SLT) and argon laser trabeculoplasty (ALT) are used to lower intraocular pressure (IOP) in patients with open-angle glaucoma (OAG). We report long-term follow-up data comparing SLT to ALT., Design: Follow-up of prospective randomized clinical trial., Participants: Patients with glaucoma from the practices of three ophthalmologists at the University of Ottawa., Methods: We randomized 176 eyes of 152 patients with uncontrolled IOP on maximal tolerated medical therapy (MTMT, with or without previous ALT) to undergo either SLT or ALT. Data were available for 142 eyes at 3 years, 134 eyes at 4 years, and 120 eyes at 5 years. The primary outcome was change in IOP from pretreatment baseline., Results: Comparison of baseline parameters was similar in the two groups. Lowering of IOP were similar at 3 years (SLT -6.7 ± 7.1 vs ALT -6.1 ± 5.1); at 4 years (SLT 7.0 ± 7.7 vs ALT -6.3 ± 5.0); and at 5 years (SLT -7.4 ± 7.3 vs ALT -6.7 ± 6.6). There was no statistically significant change in IOP in either of the two groups. Medication changes were equivalent in each group. A number of interventions were required in both groups, cumulatively, over the 5-year follow-up period (49 SLT and 33 ALT). Survival analysis indicated that the time to 50% failure in each group was approximately 2 years., Conclusions: The IOP-lowering effect of SLT and ALT was similar over 5 years in this group of patients with open-angle glaucoma on MTMT., (Copyright © 2011 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.)

Objective: To describe differences in axial length scan (A-scan) and ultrasound biomicroscopy (UBM) parameters in eyes with exfoliation syndrome (XFS) and occludable angles (XFSOc), XFS and open angles (XFSOp), and eyes with primary open-angle glaucoma (POAG)., Design: Cross-sectional descriptive study., Participants: Seventy-two eyes of 72 patients (mostly Caucasians) were identified through glaucoma clinics at the University of Ottawa;19 eyes had XFSOc, 31 eyes XFSOp, and 22 eyes POAG., Methods: After a detailed ophthalmic history and examination, A-scan biometry and UBM were done to assess anterior segment parameters: central anterior chamber depth (ACD), lens thickness, trabecular meshwork-iris angle, and angle opening distance (AOD). Lens/axial length factor and the relative lens position were calculated. The above measurements were compared across the 3 groups., Results: We found statistically significant differences in measurements among the groups. ACD was shallowest in eyes with XFSOc (1.88 [SD 0.07] mm), followed by XFSOp (2.37 [SD 0.05] mm), and POAG (2.64 [SD 0.08] mm). XFSOc had thicker lenses (5.28 [SD 0.09] mm) compared with the other groups: XFSOp (5.03 [SD 0.06] mm) and POAG (4.84 [SD 0.09] mm). Lens/axial length factor was highest in XFSOc (2.34 [SD 0.05] mm) versus XFSOp (2.12 [SD 0.03] mm) and POAG (2.02 [SD 0.05] mm); relative lens position was lowest in XFSOc (2.27 [SD 0.03] mm) versus XFSOp (2.31 [SD 0.02] mm) and POAG (2.36 [SD 0.03] mm)., Conclusions: Eyes with XFSOc in our study demonstrated lens thickening and shallow central ACD versus eyes with XFSOp and eyes with POAG. This suggests the possibility that cataract formation and (or) zonular weakness may contribute to the development of an occludable angle in eyes with XFS.

Background: This study aims to characterize the reflective properties of some commonly used intraocular lenses (IOLs) in vitro, with a particular focus on lens haptics., Methods: Six different types of IOLs, representative of silicone, acrylic, and polymethyl methacrylate (PMMA), single, multipiece, and multifocal were imaged using high-resolution ultrasound biomicroscopy (UBM)., Results: Reflectivity patterns were distinct to the material that was being imaged irrespective of whether the part being imaged was the haptic or optic. Acrylic haptics demonstrated a single "tram-track" reduplication echo, whereas PMMA haptics showed multiple reverberation echoes off the posterior surface. The optics of various PMMA and acrylic lenses demonstrated a reflectivity pattern similar to the respective haptics made of the same material. Silicone optics displayed clear delineation with no reverberation. Both acrylic and silicone material was relatively less reflective when compared with PMMA., Interpretation: With UBM imaging, the haptics of acrylic and PMMA IOLs demonstrate unique reflective patterns, depending on the material being studied. Prior knowledge of what the lens haptics and optics look like in vitro provides information that may assist in identifying and localizing misplaced intraocular lenses in vivo.

Case Report: Four years after trabeculectomy, a patient developed unilateral tearing and presented with an ipsilateral conjunctival filtering bleb that had dissected into the cornea. The corneal portion of the bleb was excised for symptomatic relief. Histopathological examination disclosed dissection of the conjunctival filtering bleb into the cornea between Bowman's layer and the corneal epithelium. The internal portion of the bleb consisted of loose stromal tissue lacking any internal epithelial lining., Comments: A conjunctival bleb dissecting into the cornea is a well-described late complication of trabeculectomy; however, its pathophysiology remains controversial. The subepithelial dissection plane in this specimen supports the concept that the conjunctival filtering bleb may dissect into, as well as "overhang", the limbal cornea.

Background: To propose consensus working recommendations for the role of central corneal thickness in the management of open-angle glaucoma., Methods: This work is based on evidence from a review of the glaucoma literature, a Canadian consensus development workshop, and the personal clinical experience of the participating Canadian ophthalmologists., Results: Guidelines were developed to provide eye care practitioners and their patients with support in the decision-making process for management of glaucoma or those at risk for developing glaucoma., Interpretation: Further studies will be helpful in understanding the role of central corneal thickness in glaucoma management, and these guidelines will need to be revised periodically as new information becomes available.

Background: To determine the efficacy and safety of trabeculectomy with mitomycin-C (trabMMC) compared with that of single-site phacotrabeculectomy with mitomycin-C (phacotrabMMC) in glaucoma patients at increased risk for filtering surgery failure., Methods: Eighty-five consecutive eyes that underwent trabMMC and 105 consecutive eyes that underwent phacotrabMMC were retrospectively compared up to 2 years postoperatively with respect to intraocular pressure (IOP), number of glaucoma medications, and surgical complication rates. The primary outcome was the difference in the cumulative proportion of patients meeting the target IOP range at 2 years. Secondary outcomes included mean postoperative IOP, mean IOP drop from baseline, mean number of glaucoma medications, and surgical complication rates., Results: Baseline characteristics were similar in the 2 groups and most patients had advanced glaucoma with a similar upper limit of the target IOP range (15.5 +/- 2.6 mm Hg for trabMMC vs. 15.3 +/- 2.1 mm Hg for phacotrabMMC, p = 0.56). Loss to follow-up was significant in both groups (almost 50% over 2 years). A statistically similar proportion of patients achieved their target IOP range at 1 and 2 years in both groups: the cumulative success rate at 2 years was 29.04% and 22.91% (p = 0.44) without add-on glaucoma therapy, 25.38% and 25.22% (p = 0.60) with the use of up to 2 glaucoma medications, and 30.01% and 25.17% (p = 0.81) with the use of any number of glaucoma medications, in the trabMMC and phacotrabMMC groups, respectively. Mean postoperative IOP was also similar between the 2 groups at almost all follow-up times up to 2 years (13.56 +/- 4.92 mm Hg in trabMMC vs. 13.98 +/- 4.74 mm Hg in phacotrabMMC at 2 years, p = 0.67). The mean IOP drop from baseline was significantly greater in the trabMMC group throughout the study period (-10.87 +/- 8.33 mm Hg in trabMMC vs. -6.15 +/- 7.01 mm Hg in phacotrabMMC at 2 years, p = 0.003); however, baseline IOP was also higher in the trabMMC group (26.1 mm Hg vs. 20.3 mm Hg, p < 0.0001). Serious postoperative complication rates were similarly low between the 2 groups., Interpretation: TrabMMC and phacotrabMMC may be equally safe and effective in bringing IOP to within an acceptable target range over 2 years in advanced glaucoma patients at increased risk for filtering surgery failure, although trabMMC appears to be associated with greater IOP lowering from baseline.

There is an abundance of evidence from recent randomized clinical trials showing that lowering the IOP is beneficial to the optic nerve and visual field. Setting and achieving a target IOP range is in keeping with evidence-based medicine. The benefits of reaching this target must be weighed against the risks of the treatment itself. Target IOP is a dynamic concept, needing constant reevaluation. What is lacking are established guidelines for determining the target IOP range that can be used in general ophthalmology practice.

Objective: In patients with dominant optic atrophy (DOA, Kjer type), excavation of the optic nerve develops, and these patients may be misdiagnosed as having normal tension glaucoma (NTG). This study examined disc morphologic features in patients with DOA and explored features that help distinguish this condition from NTG., Design: Noncomparative, observational case series., Participants: Patients with DOA who were seen at the Duke University Eye Center between 1987 and 1996 and who had bilateral optic nerve photographs., Methods: Retrospective chart review of the results of visual acuity testing, visual field testing by Goldmann perimetry, color vision testing, intraocular pressure measurement, and observation of bilateral optic nerve photographs., Main Outcome Measures: Appearance of the optic disc and peripapillary zone in patients with DOA., Results: Nine patients were identified. The mean age at the time of evaluation was 28 years (range, 11-62 years). Most patients had a mild to moderate reduction in visual acuity. Color vision as tested with Hardy-Rand-Rittler plates was reduced (4.0/10 +/- 4.2/10). A cup-to-disc ratio of more than 0.5 was observed in at least one eye of eight patients. A temporal wedge-shaped area of excavation was observed in 14 of the 18 eyes studied. Moderate to severe temporal pallor was observed in all of the eyes. Pallor of the remaining (noncupped) neuroretinal rim was also observed consistently, ranging from mild to moderate. A gray crescent and some degree of peripapillary atrophy were noted in all eyes., Conclusions: Several clinical features, including early age of onset, preferential loss of central vision, sparing of the peripheral fields, pallor of the remaining neuroretinal rim, and a family history of unexplained visual loss or optic atrophy, help to distinguish patients with DOA from those with NTG.

Background: Leber's congenital amaurosis (LCA) represents the earliest and severest form of retinal dystrophy leading to congenital blindness. A total of 20% of children attending blind schools have this disease. LCA has a multigenic basis and is proving central to our understanding of the development of the retina. We describe the clinical and molecular genetic features of four inbred pedigrees from neighbouring remote villages in northern Pakistan, in which some of the affected members have concurrent keratoconus., Methods: History-taking and physical and eye examinations were performed in the field. Venipuncture, DNA extraction, studies of linkage to known LCA genes, automated sequencing and polymorphism analyses for haplotype assessments were done., Results: We examined 12 affected and 15 unaffected family members. By history, there were an additional nine blind people in the four pedigrees. In each pedigree a consanguineous marriage was evident. We found a homozygous nonsense mutation in the AIPL1 gene, which replaces a tryptophan with a stop codon (Trp278X). The phenotype is severe and variable, despite the common molecular genetic etiology in each family. Affected patients had hand motion to no light perception vision and fundus findings ranging from maculopathy to diffuse pigmentary retinopathy. Three affected members had definite keratoconus, and two were suspects based on mild cone formation in the cornea of at least one eye., Interpretation: We have identified four Pakistani families with a severe form of LCA that is associated with severe keratoconus in some affected members. The molecular etiology in all four families is a homozygous nonsense mutation, Trp278X, in the photoreceptor-pineal gene AIPL1. To our knowledge, this is one of the first phenotype-genotype correlations of AIPL1-associated LCA.

Background: Pigment dispersion syndrome affects up to 4% of the white population. It is characterized by the presence of transillumination defects, Krukenberg's spindle and dense trabecular meshwork pigmentation. Open-angle glaucoma will develop in as many as 50% of affected patients. In this study we describe the familial occurrence of pigment dispersion syndrome in six North American pedigrees and the phenotypic characteristics with respect to pigment dispersion syndrome and glaucoma., Methods: Probands with pigment dispersion syndrome were identified in glaucoma clinics at university eye centres in Ottawa and Durham, NC. Families with two or more affected members were evaluated. All willing members in each family underwent a thorough clinical examination and were classified as affected with pigment dispersion syndrome, suspect or unaffected. The previous medical records were reviewed to obtain the past medical and ocular history, including risk factors for glaucoma., Results: All six families are white. Three families show at least two generations of affected members. Of the 43 subjects examined 58% were women. All 14 affected members showed moderate to heavy trabecular meshwork pigmentation and either Krukenberg's spindle or transillumination defects. The affected members were also considerably more myopic (mean spherical equivalent for the right eye -4.72 dioptres) than the suspect group or the unaffected group (mean spherical equivalent -0.79 D and +1.19 D respectively) (p < or = 0.001), and the intraocular pressure was higher for the affected than the unaffected group (mean for the right eye 20 mm Hg vs. 16 mm Hg) (p = 0.004). Half of those affected also had open-angle glaucoma., Interpretation: We have identified and phenotypically characterized six North American families with autosomal dominant pigment dispersion syndrome. Our ultimate goal is to identify the gene(s) that causes this disorder in order to clarify its molecular etiology and pathophysiology. This may give rise to a molecular classification of the disease as well as provide the foundation for genetic testing and new treatment approaches.