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Purpose: To determine the anatomic and visual outcomes of pars plana vitrectomy for uncomplicated, primary macula-off rhegmatogenous retinal detachment (RRD) with and without internal limiting membrane (ILM) peeling. Methods: This retrospective chart review comprised 129 patients with uncomplicated, primary macula-off RRD presenting between January 1, 2016, and May 31, 2021. Thirty-six patients (27.9%) had ILM peeling and 93 (72.0%) did not. The primary outcome was the rate of recurrent RRD. Secondary outcomes included preoperative and postoperative best-corrected visual acuity (BCVA), epiretinal membrane (ERM) formation, and macular thickness. Results: No significant difference was found in the risk for recurrent RRD between patients who had ILM peeling and those who did not (2.8% [1/36] and 5.4% [5/93], respectively) ( P = 1.00). The final postoperative BCVA was better in eyes that did not have ILM peeling ( P < .001). No ERM occurred in the group with ILM peeling, whereas ERM occurred in 27 patients (29.0%) who did not have ILM peeling. The temporal macular retina was thinner in eyes in which ILM peeling was performed. Conclusions: The risk for recurrent RRD was not statistically lower in eyes having ILM peeling of the macula in uncomplicated, primary macula-off RRD. Despite a reduction in postoperative ERM formation, eyes having macular ILM peeling had worse postoperative VA.

Purpose To present a surgical technique and case presentation of internal chandelier-assisted macular buckling for myopic foveoschisis. Methods Review of patient clinical features, visual-acuity and optical coherence tomography (OCT) results following internal chandelier-assisted macular buckling for myopic foveoschisis. Results A 48-year-old highly myopic female (axial length 29.85mm) underwent internal chandelier-assisted macular buckling for myopic foveoschisis with macular detachment. The best-corrected visual acuity improved from 20/150 to 20/40. Post-operative OCT confirmed central buckle positioning and demonstrated resolved foveoschisis and macular detachment. There were no complications. Conclusions Internal chandelier-assisted macular buckling is a valuable tool to optimize buckle position and patient outcomes.

The overall activity of cycling, although profoundly heterogenous, often occurs with mechanisms consistent with motor vehicle collisions. Advanced trauma life support is the standard of care. Traumatic brain injury is the leading cause of death, and concussions are common in cyclists. Road rash is the most common injury, and management should be synonymous with other kinds of burns. A unique aspect of cycling medicine is that it often is done on public roadways in close proximity to the athletes during competition. Clinicians who care for cyclists in the field setting should be prepared to manage a broad spectrum of traumatic injuries.

Purpose To analyze the single surgery success rate and anterior segment complications related to phacoemulsification and intraocular lens implantation in a series of patients undergoing phacovitrectomy for all types of primary rhegmatogenous retinal detachment. Methods We performed a retrospective interventional case series on 302 eyes undergoing phacovitrectomy for primary rhegmatogenous retinal detachment repair between November 1, 2016, and February 2, 2019, in Edmonton, Canada. Primary outcomes included single surgery retinal reattachment rate and anterior segment complications. Secondary outcomes included the effects of proliferative vitreoretinopathy and macula and/or peripheral internal limiting membrane peeling on the rate of surgical success. Results The single surgery success rate of phacovitrectomy for all types of primary rhegmatogenous retinal detachment was 85.1%. The presence of proliferative vitreoretinopathy was associated with lower surgical success (odds ratio, 0.33; P = 0.01). Macular internal limiting membrane peeling was associated with higher surgical success (odds ratio, 2.4; P = 0.05). Anterior segment complications included posterior capsular opacification (28.8%), posterior synechiae (10.9%), and posterior capsular rupture (2.3%). Conclusion Phacovitrectomy is a safe and effective treatment option for the primary repair of rhegmatogenous retinal detachments. This study provides evidence to support the safe incorporation of phacoemulsification and intraocular lens implantation with retinal surgery.

Purpose: To determine whether pneumatic vitreolysis with intravitreal air is effective for focal vitreomacular traction (VMT). Methods: We conducted a retrospective consecutive case series of 20 eyes from 19 individuals with focal VMT who underwent pneumatic vitreolysis with intravitreal air (January 2017 to November 2018). We analyzed patients via spectral-domain optical coherence tomography before intravitreal air injection and at 1 month. The primary outcome measure was release of VMT. Results: We observed release of VMT in 55% of individuals. An analysis limited to phakic eyes demonstrated release of VMT in 69%, and 65% developed improved best-corrected visual acuity. Individuals with persistent VMT and visual improvement had a significant reduction in angle of vitreoretinal insertion ( P < .01), area under VMT ( P < .05), and subfoveal cyst area ( P < .05). Conclusions: Intravitreal air is an effective treatment for focal VMT. In individuals with persistent VMT, visual-acuity improvement was associated with a reduction in overall VMT.

Purpose To compare the efficacy of ranibizumab using a treat-and-extend (TE monthly, n = 258). At baseline, mean age was 78.8 years (standard deviation [SD], 7.8 years), 60.3% were women, and 94.3% were white. No significant between-group baseline differences were observed. The primary outcome of noninferiority regarding visual acuity was met with mean BCVA improvement of 8.4 letters (SD, 11.9 letters) and 6.0 letters (SD, 11.9 letters; P = 0.017) in the T&E and monthly regimens, respectively, with a between-group mean difference of 2.38 letters (95% confidence interval, 0.32–4.45 letters). Per protocol, a secondary analysis was performed to test for superiority of number of injections received up to month 12. This analysis demonstrated significantly fewer injections with T&E versus monthly dosing (9.4 and 11.8 injections, respectively), with a mean difference of –2.46 injections (95% confidence interval, –2.68 to –2.23 injections). Conclusions The 12-month results of this 2-year study demonstrated that regarding visual outcomes, the T&E regimen was noninferior to a monthly dosing regimen. Similar visual outcomes in the T&E group as in the monthly dosing group were achieved with significantly fewer injections.

Purpose: The purpose of this article is to describe the characteristics and outcomes of retinal detachment (RD) repair associated with atopic dermatitis (AD). Methods: A single-center, retrospective review of all patients with RD associated with AD between January 2007 and December 2017 was conducted. Results: Ten patients (13 eyes) were included with a mean age of 23.5 ± 6.4 years; 6 of the patients were male (60%). The average follow-up was 41.3 ± 34.8 months. Seven eyes developed proliferative vitreoretinopathy (PVR) and recurrent RD (53.8%). The mean number of retinal surgeries was 2.3 ± 1.3. Three eyes had a scleral buckle alone (23.1%), 4 eyes had vitrectomy only (30.8%), and 6 eyes had both scleral buckle and vitrectomy (46.2%). Five eyes had prior cataract surgery (38.5%), 5 eyes had cataract at presentation (38.5%), and 5 eyes developed lens subluxation (38.5%). The mean presenting best-corrected visual acuity (BCVA) was 1.14 logarithm of the minimum angle of resolution (Snellen equivalent, 20/276) and the mean final BCVA was 1.06 (Snellen, 20/230; P = .83). The retina was successfully reattached at final follow-up in all 13 eyes (100%). Conclusions: RD is a challenging complication of AD with a high rate of PVR, recurrent RD, cataract, and lens subluxation. Patient education and physician awareness are necessary for timely diagnosis, appropriate counseling, and optimal surgical planning.

Introduction: The objective of this study is to assess the long-term effectiveness of a treat-and-extend (T&E) anti-vascular endothelial growth factor regimen in patients with neovascular age-related macular degeneration who remain on T&E and those switched from once-monthly (OM) dosing to T&E (OM-T&E). Methods: In this 12-month extension of the 2-year CANTREAT study, patients received intravitreal ranibizumab 0.5 mg in a T&E regimen. Main outcome measures included mean change in best-corrected visual acuity (BCVA) from baseline and from month 24 to month 36; percentages of patients who gained ≥5, ≥10, or ≥15 Early Treatment of Diabetic Retinopathy Study (ETDRS) letters or lost ≥5, ≥10, or ≥15 letters from baseline and from month 24 to month 36; and number of injections administered from baseline and from month 24 to month 36 for both groups. Results: Of the 139 patients (73 T&E, 66 OM-T&E) in the extension, 121 (68 T&E, 53 OM-T&E) completed 36 months. Mean (standard deviation [SD]) BCVA changes from baseline to the extension last visit (month 33–36) were +6.6 (11.4) letters in the T&E group and +4.8 (14.3) letters in the OM-T&E group, representing maintenance of 24-month gains. The mean (SD) numbers of injections during the extension were 7.3 (2.7) for T&E and 7.1 (2.8) for OM-T&E. Discussion/Conclusion: These findings suggest that after 36 months of treatment, the mean BCVA improvement achieved at 24 months is maintained for both the patients exclusively treated with the T&E regimen and those that switched to T&E after 24 months in the OM regimen.

Although the Canadian Treat-and-Extend Analysis Trial With Ranibizumab in Patients With Neovascular Age-Related Macular Disease (CANTREAT) reported herein and the Treat and Extend study provided data to show noninferiority of treat-and-extend (TE) at 12 months, to date there are few data on 24-month TE trials compared with monthly dosing.To compare the efficacy of ranibizumab using a TE regimen to monthly dosing in treatment-naive patients with neovascular age-related macular degeneration (nAMD) after 24 months.A randomized, open-label, multicenter, noninferiority intention-to-treat trial with a margin of -5 letters in best-corrected visual acuity (BCVA) from baseline to 12 months between groups was conducted at 27 treatment centers in Canada. Participants included 580 patients with treatment-naive choroidal neovascularization secondary to AMD. The study was conducted from May 8, 2013, to August 28, 2018, and data analysis was performed between August 29 and September 12, 2018.Patients with nAMD were randomized 1:1 to receive intravitreal ranibizumab, 0.5 mg, in either a TE or monthly dosing regimen.Mean change in BCVA in Early Treatment of Diabetic Retinopathy Study letters from baseline to month 24.Of the 580 randomized patients, 350 were women (60.3%) and 547 were white (94.3%). Mean (SD) age was 78.8 (7.8) years. By the end of month 24, 466 of the 580 randomized patients (80.3%) had completed the study and participants in the TE arm received a mean of 17.6 injections compared with 23.5 injections for the monthly arm, for a difference of 5.9 injections and visits over 2 years (95% CI, 5.4-6.5; P .001). The mean (SD) BCVA improvement was not worse with the TE arm, 6.8 (14.1) letters vs 6.0 (12.6) letters, compared with the monthly arm (difference, 0.9; 95% CI, -1.6 to 3.3; P = .21). There was a gain of 15 or more letters in 25.5% of the TE group and 23.1% of the monthly treatment group (difference, 2.4%; 95% CI, -6.8% to 11.6%; P = .59) and a loss of 15 or more letters in 6.5% of the TE group and 5.8% of the monthly treatment group (difference, -0.7%; 95% CI, -9.9% to 8.5%; P = .85).These findings suggest that change in vision from baseline is not worse with a TE compared with a monthly regimen of ranibizumab for nAMD through 24 months, achieving clinically meaningful improvements in BCVA despite fewer injections and visits.ClinicalTrials.gov identifier: NCT02103738.

We present a unique case of food dependent exercise induced anaphylaxis (FDEIA) triggered by an inhaled allergen in a 23- year-old professional cyclist. FDEIA is considered a rare form of anaphylaxis in which the state of exercise can trigger mast cell degranulation to an allergen which normally does not cause a reaction. It is closely related to exercise induced anaphylaxis, which occurs with exercise but in the absence of a food trigger. The patient experienced an anaphylactic reaction during a bicycle race when the race went through an almond orchard in full bloom. He was successfully stabilized with aggressive measures including steroids, fluids, anti-histamines and multiple doses of epinephrine.

To compare the efficacy of ranibizumab using a treat-and-extend (TE) regimen with monthly dosing in treatment-naive patients with neovascular age-related macular degeneration (nAMD).Prospective, randomized, open-label, multicenter, noninferiority, postauthorization study.Treatment-naive patients with choroidal neovascularization secondary to AMD.Patients with nAMD were randomized 1:1 to receive intravitreal ranibizumab at a dose of 0.5 mg in either a TE or monthly dosing regimen. The noninferiority of TE compared with the monthly dosing regimen was to be shown using a margin of 5 letters in best-corrected visual acuity (BCVA) improvement.Mean change in BCVA in Early Treatment Diabetic Retinopathy Study letters from baseline to month 12.Baseline and 12-month visual acuity data are available for 526 patients (TE, n = 268; monthly, n = 258). At baseline, mean age was 78.8 years (standard deviation [SD], 7.8 years), 60.3% were women, and 94.3% were white. No significant between-group baseline differences were observed. The primary outcome of noninferiority regarding visual acuity was met with mean BCVA improvement of 8.4 letters (SD, 11.9 letters) and 6.0 letters (SD, 11.9 letters; P = 0.017) in the TE and monthly regimens, respectively, with a between-group mean difference of 2.38 letters (95% confidence interval, 0.32-4.45 letters). Per protocol, a secondary analysis was performed to test for superiority of number of injections received up to month 12. This analysis demonstrated significantly fewer injections with TE versus monthly dosing (9.4 and 11.8 injections, respectively), with a mean difference of -2.46 injections (95% confidence interval, -2.68 to -2.23 injections).The 12-month results of this 2-year study demonstrated that regarding visual outcomes, the TE regimen was noninferior to a monthly dosing regimen. Similar visual outcomes in the TE group as in the monthly dosing group were achieved with significantly fewer injections.

Objective To present the outcomes of scleral buckle (SB) removal with and without concurrent prophylactic laser retinopexy. Design Retrospective, interventional case series. Participants Eighty-seven eyes of 87 patients who had SB removal after primary rhegmatogenous retinal detachment repair. Methods All patients who had SB removal after primary rhegmatogenous retinal detachment repair from both Wills Eye Institute and University of Alberta from 2000 to 2011 were identified. All patients had a minimum of 6 months of follow-up. Results Eighty-seven patients met the study criteria. Primary indications for SB removal were extrusion (76%, n=66), diplopia (8%, n=7), infection (6%, n=5), a combination of extrusion and infection (6%, n=5), and others (5%, n=4). Only 3 of 87 eyes (3.4%) developed a recurrent retinal detachment after SB removal. Only 1 eye (2.2%) from the group that received laser retinopexy (n = 45) at the time of SB removal had a retinal redetachment, whereas 2 eyes (4.2%) in the group that did not receive laser (n = 42) had a recurrent retinal detachment ( p = 0.61). Conclusions The overall rate of recurrent retinal detachment after SB removal was low. No significant difference in recurrent retinal detachment was found between the eyes that received prophylactic laser retinopexy compared with those that did not at the time of SB removal.

Ce document a pour objet de fournir aux ophtalmologistes canadiens des indications de depistage et diagnostic de la retinopathie diabetique (RD) et de gestion du diabete en ce qui concerne particulierement la RD, et de proposer des approches chirurgicales et non chirurgicales de traitement de la RD. Ce guide concerne la population canadienne de toutes origines ethniques aux prises avec le diabete de type 1 ou 2. Les autres professionnels de la sante intervenant dans le soin des personnes diabetiques pourront aussi trouver ce document utile. Ce guide a ete elabore systematiquement a partir d’un examen minutieux de la litterature medicale et de l’experience clinique. Il ne cherche pas a restreindre l’innovation. En effet, les guides n’ont pas pour objet de proposer des « recettes » d’exercice de la medecine ni de remplacer le jugement clinique, mais plutot d’informer les tendances de la pratique. L’adhesion a ce guide ne produira pas necessairement des resultats favorables dans chaque cas. Qui plus est, il ne doit pas servir de ressource juridique, car sa nature generale ne permet pas d’en faire un instrument personnalise a chaque patient en toutes circonstances. Les guides ne veulent pas definir des normes juridiques de soins medicaux et ne doivent pas servir a cette fin. Les normes de soins medicaux sont particulieres a chaque cas, selon l’ensemble des faits et des circonstances, et peuvent changer a mesure de la progression du savoir scientifique et de la technologie et de l’evolution des tendances de la pratique. On ne s’attend pas a ce que ce guide soit applique dans un cadre de recherche. Aucun commentaire n’est formule quant aux repercussions financieres des interventions recommandees dans ce guide. Idealement, les guides de pratique sont des outils souples bases sur les meilleures donnees probantes scientifiques et cliniques disponibles; ils expriment le consensus de professionnels du domaine et permettent aux medecins d’utiliser

To describe the phenotype and genotype of patients with autosomal recessive bestrophinopathy.The phenotype of the subjects was described after a complete ophthalmological examination, and in various cases, ancillary testing of the visual field, optical coherent tomography, full field electroretinography and electrophysiology. Genetic analysis was carried out by screening the Bestrophin-1 (BEST1) gene for mutations by dideoxy sequencing and segregation analysis.We identified three previously described mutations (Ala195Val, Leu191Pro and Arg141His) and two potentially pathogenic changes (Trp93Pro and Trp287Ter) in the Best-1 gene. Two patients carried compound heterozygous mutations, Trp93Pro/Ala195Val, and Leu191Pro/Trp287Ter. Two sisters were homozygous for an Arg141His mutation. All individuals with Best1 gene mutations had signs of maculopathy.Our observations expand the limited number of phenotypes associated with mutations in the Best1 gene. Patients with compound heteroyzygous Best1 mutations developed atypical forms of Best disease. Two siblings with homozygous Arg141His mutation developed symptoms of typical Best vitelliform dystrophy while their parents had clinical features of mild maculopathy.

Aims Individuals with diabetic retinopathy (DR) represent a high-risk group who would benefit from intensive metabolic control and risk factor management. This brief report examines quality of care among diabetic patients attending a tertiary retinal clinic. Methods A cross-sectional survey, notes review, and slit-lamp examination was conducted in 139 diabetic patients attending a specialist retinal clinic to assess the quality of comprehensive diabetes care. DR was graded according to the Early Treatment Diabetic Retinopathy Study scale. Results The prevalence of non-proliferative DR (NPDR) and proliferative DR (PDR) was 39.6 and 35.2%, respectively. The prevalence of microalbuminuria in patients with no DR, NPDR and PDR was 32, 54.1 and 68.8%, respectively. Glycaemic control was suboptimal (mean HbA1c 8.0 ± 1.8%) and 15.8% were current smokers. Drugs affecting the renin–angiotensin system were used by only 61.9% of patients with both DR and microalbuminuria, and aspirin by only 35.3%. Conclusions These data suggest that diabetes care in this high-risk population with established microvascular complications was suboptimal. Specialist clinics dealing with diabetic complications may be a setting where quality improvement strategies to reduce morbidity and mortality should be focused.

To explore the use of helmets in skiers and snowboarders injured at ski runs and terrain parks in Colorado and the northeast United States and to examine differences in head injury severity in terrain parks as compared to ski runs.This was a retrospective cohort study. We reviewed emergency department medical records of injured skiers at 9 medical facilities in Colorado, New York, and Vermont to examine the frequency of helmet use, type of terrain on which injuries occurred, and effect of injury event type and helmet use on change in mental status. Injuries that occurred from July 2002 to July 2004 were included. Eligible patients were skiers and snowboarders who sustained a head injury as defined by International Classification of Diseases-9 codes for acute head injuries. Data elements included event location, mechanism of injury, helmet use, loss of consciousness, neurologic findings, Glasgow Coma Scale score, and initial outcome. Data were entered into SPSS for analysis.Of 1013 patients, 52.6% were skiing, 46.7% were snowboarding, and the remainder engaged in other activities such as sledding or using a sit ski. Most (78.7%) were using a ski run, whereas 19.1% were at a terrain park when their injuries occurred, and 37.1% were wearing helmets. Most injuries (74.1%) occurred when the victim hit his/her head on the snow; 10.0% and 13.1% occurred in collisions with other skiers and fixed objects, respectively. There were significantly fewer instances of loss of consciousness in fall events in the Colorado group (chi(2): 4.127; P.05), a significantly lower incidence of loss of consciousness in helmet users who struck a fixed object (chi(2): 5.800; P.05), and a significantly higher incidence of skiers colliding with fixed objects in the Northeast (chi(2): 14.05; P.005). There were significantly more documented head injuries in terrain parks, even when controlling for helmet use (chi(2): 5.800; P.05).There is an increased risk of head injury, regardless of helmet use, at terrain parks as compared to ski runs, and helmets were notably protective in collisions with fixed objects. Regional differences in injury events were noted in that there were more fall-related head injuries and a higher incidence of collisions with fixed objects in the Northeast compared to Colorado.

Traumatic brain injury is a major source of death and disability worldwide. Significant success has been achieved in improving short-term outcomes in severe traumatic brain injury victims; however, there are still great limitations in our ability to return severe traumatic brain injury victims to high levels of functioning. Primary brain injury, due to initial injury forces, causes tissue distortion and destruction in the early postinjury period. Clinical outcomes depend in large part on mediating the bimolecular and cellular changes that occur after the initial injury. These secondary injuries from traumatic brain injury lead to alterations in cell function and propagation of injury through processes such as depolarization, excitotoxicity, disruption of calcium homeostasis, free-radical generation, blood-brain barrier disruption, ischemic injury, edema formation, and intracranial hypertension. The best hope for improving outcome in traumatic brain injury patients is a better understanding of these processes and the development of therapies that can limit secondary brain injury.

Purpose To evaluate the ability of Joint Photographic Experts Group (JPEG) compressed, stereoscopic, digital photography to identify clinical levels of diabetic retinopathy, detect clinically significant macular edema (CSME), and make appropriate referral recommendations as compared with Early Treatment Diabetic Retinopathy Study (ETDRS) standard film photography. Design Prospective, clinic-based, comparative photographic format validation study. Participants Two hundred four eyes from 102 consecutive, new, diabetic patients with a median duration of diabetes of 12.5 years were enrolled and analyzed. Methods After pupillary dilation, a trained ophthalmic photographer obtained 2 sets of images: standard ETDRS, stereoscopic 7-field 35-mm film photographs and high-resolution, digital images of the same 7 standard fields (stereoscopic images of fields 1 and 2). Two masked readers graded both sets of images. The 35-mm film photographs were graded by hand using a written template. Digital photographs were compressed, uploaded to a web site, and graded by a web-based, computer-assisted ETDRS algorithm. The ETDRS level of diabetic retinopathy, presence of retinal thickening, and referral recommendation based on these 2 diagnoses were recorded and compared. Main Outcome Measures The presence of CSME, ETDRS level of diabetic retinopathy, and referral threshold diabetic retinopathy. Results Film and compressed digital grading levels were compared using a simplified ETDRS categorization scheme. Film and digital gradings were highly correlated with exact agreements for level of diabetic retinopathy, CSME, and referral thresholds >87% and κ levels >0.71. McNemar's testing found no statistically significant difference between compressed digital images and film when comparing referral thresholds (defined as the presence of CSME and/or ETDRS level ≥ 61; P = 0.76). Conclusions A modified ETDRS protocol (stereoscopic images of fields 1 and 2 only) with 16:1 JPEG image compression and computer-assisted ETDRS grading algorithm has excellent reproducibility when compared to standard ETDRS stereoscopic slide-film photography. An internet-based teleophthalmology system can correctly and reliably (κ = 0.78) identify patients requiring referral for CSME and proliferative diabetic retinopathy (PDR; ETDRS level ≥ 61).

Objective: Identifying diabetes complications through screening using portable laboratory equipment in Aboriginal communities, and providing education and client empowerment for improved follow-up care and self-care. Participants: First Nations people with known diabetes. Setting: Screening was carried out in temporary clinics and laboratories set up at the local health centre in each of Alberta’s 44 First Nations. Intervention: Two mobile units (“SLICK vans”), equipped with professionally trained staff, portable lab instruments and a retinal camera, travelled to all 44 Alberta First Nations communities to facilitate implementation of the Canadian Diabetes Association Clinical Practice Guidelines (CPGs). The project provided relevant education and counselling in conjunction with screening activities. Outcomes: SLICK screened 1,151 clients between December 2001 and July 2003, and the project remains ongoing. A preliminary evaluation of the project’s 19-month implementation period showed screening activities and satisfaction with diabetes services were low prior to SLICK. There were modest improvements in some program outcomes at 6–12 months follow-up. Conclusion: The SLICK project is designed to address the impact of diabetes by utilizing evidence-based CPGs with respect to screening for complications at the community level. It had a successful implementation period facilitated by community acceptance.

Background: Canada's vast size and remote rural communities represent a significant hurdle for successful monitoring and evaluation of diabetic retinopathy.Teleophthalmology may provide a solution to overcome this problem. We investigated the application of joint Photographic Experts Group (JPEG) compression to digital retinal images to determine whether JPEG compression could reduce file sizes while maintaining sufficient quality and detail to accurately diagnose diabetic retinopathy. Methods: All 20 patients with type 2 diabetes mellitus assessed at a 1-day teleophthalmology clinic in northern Alberta were enrolled in the study. Following pupil dilation, seven 30° fields of each fundus were digitally photographed at a resolution of 2008 × 3040 pixels and saved in uncompressed tagged image file format (TIFF). The files were compressed approximately 55× and 113× their original size using JPEG compression. A reviewer in Edmonton randomly viewed all original TIFF images along with the compressed JPEG images in a masked fashion for image quality and for specific diabetic retinal pathology in accordance with Early Treatment Diabetic Retinopathy Study standards. The level of diabetic retinopathy and recommendations for clinical follow-up were also recorded. Exact agreement and weighted κ statistics, a measure of reproducibility, were calculated. Results: Exact agreement between the compressed JPEG images and the TIFF images was high (75% to 100%) for all measured variables at both compression levels. Reproducibility was good to excellent at both compression levels for the identification of diabetic retinal abnormalities (κ = 0.45–1), diagnosis of level of retinopathy (κ = 0.73–1) and recommended follow-up (κ = 0.64–1). Interpretation: The application of JPEG compression at ratios of 55:1 and 113:1 did not significantly interfere with the identification of specific diabetic retinal pathology, diagnosis of level of retinopathy or recommended follow-up.These results indicate that JPEG compression at ratios as high as 113:1 has the potential to reduce storage requirements without interfering with the accurate and reproducible teleophthalmologic diagnosis of diabetic retinopathy. This pilot project demonstrates the potential for JPEG compression within a digital teleophthalmology viewing system.

Background: The availability of new therapeutic approaches, particularly intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapies, has prompted significant changes to the established treatment paradigms for retinal vein occlusion (RVO). Better visual outcomes and significantly lower rates of adverse events have been noted in multiple large randomized clinical trials and have led to a new standard of care for this sight-threatening condition. Objective: To develop an expert consensus for the management of RVO and associated complications in the context of recent clinical evidence. Methods: The development of a Canadian expert consensus for optimal treatment began with a review of clinical evidence, daily practice, and existing treatment guidelines and algorithms. The expert clinicians (11 Canadian retina specialists) met on February 1, 2014, in Toronto to discuss their findings and to propose strategies for consensus. Results: The result of this expert panel is a consensus proposal for Canadian ophthalmologists and retina specialists treating patients presenting with RVO. Treatment algorithms specific to branch and central RVO (BRVO and CRVO) were also developed. Conclusions: The consensus provides guidelines to aid clinicians in managing RVO and associated complications in their daily practice. In summary, laser remains the therapy of choice when neovascularization secondary to RVO is detected. Adjunctive anti-VEGF could be considered in managing neovascularization secondary to RVO in cases of vitreous hemorrhage. Intravitreal anti-VEGF should be considered for symptomatic visual loss associated with center-involving macular edema on optical coherence tomography. Patients with BRVO and a suboptimal response to anti-VEGF could be treated with grid laser, and those with CRVO and an inadequate response to anti-VEGF may be candidates for intravitreal steroids.

Diabetic eye disease is present in remote communities across Canada. A pilot study was designed to assess the feasibility of stereoscopic digital imaging to identify levels of diabetic retinopathy via teleophthalmology. Diabetic patients were assessed for diabetic retinopathy by seven field stereoscopic digital imaging through a dilated pupil. Images were transferred by satellite to a tertiary eye center for review by a retinal specialist. Images were viewed stereoscopically on a video monitor, with grading of all images using a modified Early Treatment Diabetic Retinopathy Study (ETDRS) classification. Patients found to have treatable diabetic retinopathy were transferred to a tertiary eye center for assessment and treatment by a retinal specialist. One hundred patients (199 eyes) had stereoscopic digital imaging of the retina. Microaneurysms were identified in 70 eyes, hard exudates in 31 eyes. Two eyes were identified with neovascularization of the disc (NVD) and 15 eyes with clinically significant macular edema (CSME). All eyes identified by stereoscopic digital imaging with treatable disease were confirmed by clinical examination with contact lens biomicroscopy. Stereoscopic digital imaging of the retina enables the identification of diabetic retinopathy. Further research is needed to delineate the sensitivity and specificity of stereoscopic digital imaging when compared to slide film and clinical examination.

* BACKGROUND AND OBJECTIVE: To evaluate a macular buckle for exudative choroídal neovascularization secondary to age-related macular degeneration (ARMD). * PATIENTS AND METHODS: Forty-two eyes with choroidal neovascular membranes (CNVM) secondary to ARMD underwent surgical placement of a macular buckle. A Gore-Tex strip (2.0-2.5 mm wide) was button-holed through a 5 mm diameter silicone sponge (9 mm long) and placed behind the macula underneath the CNVM by the same surgeon (Dr Peyman) in all cases. Follow-up ranged from 7-76 months (mean, 20.9 months). * RESULTS: Of 12 eyes with classic subfoveal CNVM: 4 (33%) gained 2 or more lines of Snellen visual acuity; 3 (25%) gained 1 line, remained the same, or lost 1 line; and 5 (42%) lost 2 or more lines range + 6 to - 6 lines). Of 22 eyes with ill-defined subfoveal CNVM: 12 (54%) gained 1 line, remained the same, or lost 1 line; and 10 (46%) lost 2 or more lines (range + 1 to - 8 lines). Eight eyes with illdefined juxtafoveal CNVM had the following visual acuity outcomes: 5 eyes (62%) maintained the same level of Snellen visual acuity (gained 1 , O, or lost 1 line); and 3 (38%) got worse (lost 2 or more lines of Snellen visual acuity, range + 1 to - 6 lines). Ten eyes (24%) bled subretinally during the follow-up period (average 11.5 months, range 14 days to 27 months), all outside the area of indentation of the macular buckle. * CONCLUSIONS: The macular buckle treatment for exudative subretinal choroidal neovascular membranes in ARMD stabilized visual decline and displaced significant subfoveal hemorrhage. [Ophthalmic Surg Lasers 1999;30:619-630.]

Case report: Sympathetic ophthalmia typically presents as bilateral granulomatous panuveitis that occurs after penetrating ocular injury. We describe a case of bilateral exudative retinal detachments in a patient with Turner syndrome and sympathetic ophthalmia. Comments: To our knowledge, this is the first report of sympathetic ophthalmia in Turner syndrome.

Retinopathy of prematurity (ROP), a leading cause of pediatric blindness, predominantly affects premature and low-birth-weight infants. Although many cases are self-limiting, a minority progress to retinal detachment despite treatment. Exudative retinal detachments, although uncommon, have been reported after conventional laser therapy.(1-3) We report 2 cases of exudative retinal detachment after laser therapy for prethreshold and threshold ROP that responded favourably to a series of intravitreal bevacizumab injections.

Recent advances in the therapeutic options and approaches for diabetic retinopathy (DR) and diabetic macular edema (DME) have resulted in improved visual outcomes for many patients with diabetes. Yet, they have also created many clinical dilemmas for treating ophthalmologists and retina specialists, including treatment selection, initiation, frequency and duration. With this in mind, a panel of Canadian retina specialists met and discussed the current clinical evidence as well as specific situations and scenarios commonly encountered in daily practice. They also shared their experiences and therapeutic approaches. This document, containing a consensus on treatment algorithms for various clinical scenarios, is the result of their lengthy and in-depth discussions and considerations. The intent is to provide a step-by-step approach to the treatment of DR and DME. Although clinicians are encouraged to use and refer to these algorithms as a guide for various situations, they are not meant to be a replacement for sound clinical judgment.

The objective of this document is to provide guidance to Canadian ophthalmologists regarding screening and diagnosis of diabetic retinopathy (DR), management of diabetes as it pertains specifically to DR, and surgical and nonsurgical approaches to the treatment of DR. These guidelines apply to all Canadians with type 1 or type 2 diabetes of all ethnic origins. Other health professionals involved in the care of people with diabetes may find this document helpful. These guidelines were systematically developed and based on a thorough consideration of the medical literature and clinical experience. These guidelines are not meant or intended to restrict innovation. Guidelines are not intended to provide a “cookbook” approach to medicine or to be a replacement for clinical judgment; rather, they are intended to inform patterns of practice. Adherence to these guidelines will not necessarily produce successful outcomes in every case. Furthermore, these guidelines should not be used as a legal resource, as their general nature cannot provide individualized guidance for all patients in all circumstances. Guidelines are not intended to define or serve as a legal standard of medical care. Standards of medical care are specific to all the facts or circumstances involved in an individual case and can be subject to change as scientific knowledge and technology advance, and as practice patterns evolve. There is no expectation that these guidelines be applied in a research setting. No comment is made on the financial impact of procedures recommended in these guidelines. Ideally, guidelines are flexible tools that are based on the best available scientific evidence and clinical information, reflect the consensus of professionals in the field, and allow physicians to use their individual judgment in managing their patients. These guidelines

RESUME Background: New therapeutic approaches, particularly anti-vascular endothelial growth factor (anti-VEGF) therapies, prevent, and in some cases reverse, vision damage caused by age-related macular degeneration (AMD). Unequal access to care across Canada remains a problem for many retina specialists and their patients. Objective: To develop a consensus concerning the management of patients with exudative age-related macular degeneration (AMD). Design: Consensus document. Participants: Ten Canadian retina specialists. Methods: The development of a consensus among Canadian experts concerning optimal treatment of AMD began with a review of the clinical evidence, daily practices, existing guidelines, and current national and international approvals and policies. The experts met on June 29, 2010, in Quebec City to discuss their findings and to propose strategies for consensus. Results: The result of this expert panel is a consensus proposal for Canadian ophthalmologists and retina specialists who are treating patients with or at risk for developing neovascular AMD. Conclusions: The consensus provides guidelines to aid retina specialists in managing exudative AMD. Currently, ranibizumab is the only agent with sufficient Level I evidence and a Health Canada-approved indication for the treatment of wet AMD. Bevacizumab has been shown to be noninferior in preserving and improving visual acuity when compared to ranibizumab. Potential safety differences between the 2 drugs remain to be elucidated. The positioning of ranibizumab in this therapeutic area will be further defined as additional data for existing and emerging therapies become available. Until then, this agent remains the therapy of choice for individuals with neovascular AMD.

We consider the problem of representing numbers in close to optimal space and supporting increment, decrement, addition and subtraction operations efficiently. We study the problem in the bit probe model and analyse the number of bits read and written to perform the operations, both in the worst-case and in the average-case. A counter is space-optimal if it represents any number in the range [0, . . . , 2n - 1] using exactly n bits. We provide a space-optimal counter which supports increment and decrement operations by reading at most n - 1 bits and writing at most 3 bits in the worst-case. To the best of our knowledge, this is the first such representation which supports these operations by always reading strictly less than n bits. For redundant counters where we only need to represent numbers in the range [0, . . . , L] for some integer L < 2n - 1 using n bits, we define the efficiency of the counter as the ratio between L + 1 and 2n. We present various representations that achieve different trade-offs between the read and write complexities and the efficiency. We also give another representation of integers that uses n + O(log n) bits to represent integers in the range [0, . . . , 2n - 1] that supports efficient addition and subtraction operations, improving the space complexity of an earlier representation by Munro and Rahman [Algorithmica, 2010].

The mode of a multiset of labels, is a label that occurs at least as often as any other label. The input to the range mode problem is an array A of size n. A range query [i, j] must return the mode of the subarray A[i], A[i+1],...,A[j]. We prove that any data structure that uses S memory cells of w bits needs Ω(log n/log(Sw/n)) time to answer a range mode query. Secondly, we consider the related range k-frequency problem. The input to this problem is an array A of size n, and a query [i, j] must return whether there exists a label that occurs precisely k times in the subarray A[i], A[i+1],...,A[j]. We show that for any constant k > 1, this problem is equivalent to 2D orthogonal rectangle stabbing, and that for k = 1 this is no harder than four-sided 3D orthogonal range emptiness. Finally, we consider approximate range mode queries. A c-approximate range mode query must return a label that occurs at least 1/c times that of the mode. We describe a linear space data structure that supports 3-approximate range mode queries in constant time, and a data structure that uses O(n/e) space and supports (1 + e)-approximation queries in O(log 1/e) time.

We study the following one-dimensional range reporting problem: On an array A of n elements, support queries that given two indices i ≤ j and an integer k report the k smallest elements in the subarray A[i..j] in sorted order. We present a data structure in the RAM model supporting such queries in optimal O(k) time. The structure uses O(n) words of space and can be constructed in O(n logn) time. The data structure can be extended to solve the online version of the problem, where the elements in A[i..j] are reported one-by-one in sorted order, in O(1) worst-case time per element. The problem is motivated by (and is a generalization of) a problem with applications in search engines: On a tree where leaves have associated rank values, report the highest ranked leaves in a given subtree. Finally, the problem studied generalizes the classic range minimum query (RMQ) problem on arrays.

Background: Radial optic neurotomy (RON) is a new surgical procedure that has, until now, been studied only in a case series format. This study was designed to evaluate the efficacy of RON in improving visual acuity in patients suffering from central retinal vein occlusion (CRVO) with visual acuity equal to or worse than 20/100. Methods: A retrospective cohort study was conducted of consecutive CRVO patients, consisting of 19 who underwent RON and 38 observation subjects matched on presenting visual acuity. Results: The observation group worsened by 0.25 logMAR units from baseline, whereas the surgery group improved by 0.29 logMAR. Multivariate linear regression modelling found that, having controlled for other significant predictors and confounders, the change in visual acuity in the surgery patients was 0.63 logMAR units better than in the observation patients. Interpretation: Our data suggest that RON is a promising treatment for visual acuity loss in severe CRVO causing visual acuity equal to or worse than 20/100. These results should be interpreted cautiously because of the limitations of the study, including the retrospective study design and the use of Snellen visual acuity. Our data suggest that further evaluation of RON is warranted.

The need to incorporate stereopsis into a teleophthalmology system is controversial. Detection of hard exudate in the macula is suggested by some as an adequate surrogate for direct observation of retinal thickening. This study was designed to determine how accurate the detection of hard exudate is as a surrogate for stereoscopic detection of clinically significant macular edema (CSME).120 patients with diabetes underwent clinical retinal examination with contact-lens biomicroscopy by a retinal specialist. The presence or absence of CSME was recorded. On the same day as clinical grading, 30 degrees stereoscopic digital photographs of the macula were captured. At least 2 months after clinical examination, the digital images were viewed by masked graders for the presence or absence of hard exudate and retinal thickening.207 eyes of 106 patients had complete data sets for both diagnostic modalities. The sensitivity of hard exudate (93.9%) in predicting the presence of CSME was similar to that of direct stereoscopic observation of retinal thickening (90.9%), with p = 0.5. On the other hand, digital stereopsis was significantly more specific (92.9%) than was hard exudate (81.6%) in predicting the presence of CSME (p0.001). This difference was maintained even when controlling for image quality.Although the presence of hard exudate within the macula is a sensitive surrogate marker for CSME, it is less specific than stereoscopic evaluation. Any American Telemedicine Association category 3 teleophthalmology system that utilizes hard exudate as a surrogate marker for CSME may refer patients unnecessarily for clinical evaluation.

Emergency medicine plays a significant role in injury prevention through the use of public health models that link injury data to prevention programming, research, and advocacy. The day-to-day experiences in the emergency department provide a picture of the injury problem in a given community and give the emergency practitioner a real-world basis for injury prevention efforts. This article covers the basics or injury prevention, including defining the problem, discussing data and conceptual aspects of injury prevention, and systematically identifying successful approach to reducing the burden of injuries.

Background: This study compared the sensitivity and specificity of stereoscopic digital photography of the retina through a dilated pupil with a 45° nonmydriatic camera and Joint Photographic Experts Group (JPEG) compression of the images with the sensitivity and specificity of 35-mm slide film photography in the identification of age-related macular degeneration (AMD). Methods: Consecutive patients with a diagnosis of AMD were enrolled. Stereoscopic retinal images of the disc,macula and temporal macula were captured with a digital 45° nonmydriatic camera (then compressed into JPEG format) and with a standard fundus camera and slide film. A single retinal specialist graded both image formats in masked fashion, at least 1 month apart, using a modified Age-Related Eye Disease Study (AREDS) severity scale.The digital images were displayed on a monitor and viewed with the use of liquid crystal display shutter glasses and stereo imaging software.The film images were mounted on a light box and graded with the use of a stereoviewer. Primary outcome measures included the presence or absence of AMD pathological features. Positive and negative predictive values (PPVs and NPVs), sensitivity, specificity and weighted κ w statistics were calculated. Results: We photographed 203 eyes (of 103 patients) with both digital and slide film cameras. Correlation of the 2 image formats was substantial in identifying AREDS level 3a or greater (κ w = 0.64, standard error=0.08, PPV=0.95, NPV=0.66, sensitivity=0.93, specificity=0.74) and excellent in identifying level 4b or greater (κ w = 0.83, standard error=0.05, PPV=0.81, NPV=0.98, sensitivity=0.94, specificity=0.94). Interpretation: High-resolution stereoscopic, mydriatic, 45° digital images captured with a nonmydriatic camera and JPEG compressed correlate well with stereoscopic slide film photographs in the identification of moderate to advanced AMD (AREDS level 3a or greater).