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Purpose To investigate patient-level factors associated with first-line glaucoma therapy with laser trabeculoplasty (LT) versus topical medication. Design Population-based study. Participants All patients 66 years of age and older in Ontario, Canada, receiving first-ever therapy for glaucoma with either LT or topical medication between April 1, 2007, and March 31, 2019. Methods Linked health care databases were used to identify patients receiving first-line glaucoma therapy and to ascertain patient-level factors potentially associated with receipt of LT versus medication. Multivariate logistic regression analyses were undertaken. Main Outcome Measures Factors associated with receiving LT versus medications were evaluated using adjusted odds ratios (ORs) for age, gender, previous cataract surgery, previous corneal transplantation, previous retina surgery, level of systemic comorbidity, socioeconomic status (SES), and rural versus urban residence. Results In total, 194 759 patients were included. Older patients were less likely to be treated with LT versus medication (≥81 years of age vs. 66–70 years of age: OR, 0.49; 95% confidence interval [CI], 0.48–0.50), whereas women were more likely than men to receive LT (OR, 1.42; 95% CI, 1.39–1.45). Previous ocular surgeries were associated with decreased probability of treatment with LT, including cataract surgery (OR, 0.31; 95% CI, 0.30–0.32), corneal transplantation (OR, 0.39; 95% CI, 0.31–0.49), and retina surgery (OR, 0.46; 95% CI, 0.41–0.51). Patients with high comorbidity were less likely to receive LT (highest vs. lowest level of comorbidity: OR, 0.94; 95% CI, 0.91–0.97). Laser trabeculoplasty use was less likely among patients at higher levels of SES (highest vs. lowest level: OR, 0.86; 95% CI, 0.84–0.89) and from a rural residence (versus urban: OR, 0.92; 95% CI, 0.90–0.95). Increasing utilization of LT over time was noted (for each additional calendar year: OR, 1.05 per year; 95% CI, 1.05–1.05 per year). Conclusions Our results identified patient characteristics associated with use of LT as primary therapy for glaucoma, including factors related to patient demographics, ocular history, and comorbidity. Many of these associations are unexpected based on efficacy data or evidence-based guidelines. These results are topical considering growing evidence supporting use of first-line LT.

To explore the utility of the Catquest 9SF visual function (VF) questionnaire along with visual acuity (VA) for determining appropriateness and priority for cataract surgery. To evaluate the feasibility of administering the Catquest-9SF in a clinical setting using web-based electronic data capture and interpretation.Prospective multicentred interventional observational study.Subjects undergoing sequential cataract surgery in both eyes at 4 sites in Ontario.We recorded best-corrected VA (BCVA) and VA with current correction (CCVA) in each eye and both eyes (OU) and Catquest-9SF responses on a tablet before and after cataract surgery. Linear regression models were employed to test for associations between VA and visual function (VF).Preoperative BCVA and CCVA in the worse eye were significant predictors of change in VF (p = 0.006 and p = 0.008, respectively); subjects with worse VA had a greater improvement in VF after surgery. There was a significant association between improvement in VF and improvement in CCVA OU (p = 0.001). Fourteen of 151 subjects (9%) had no improvement or worse VF scores after surgery. Within this group, 10 of 14 subjects had a preoperative score ≤-3, which is suggestive of minimal visual disability. Within this subset, 4 of 14 subjects (2.6%) had a preoperative BCVA of 20/30 or better in their worse eye.For patient groups with equal VA, the Catquest-9SF score can help determine priority for surgery. Web-based data capture and interpretation allow for efficient virtual assessments of VF. A BCVA in the worse eye of 20/30 or better combined with a Catquest-9SF score-3 can be used as a guideline for lowest priority.

An important potential unintended consequence of the growth of surgical subspecialization is the narrowing of surgical practice among comprehensive ophthalmologists. We investigated trends in the narrowing of surgical practice and the exclusive provision of cataract surgery.Population-based, retrospective study.All ophthalmologists and all ophthalmologic surgical patients in Ontario from 1994 to 2016.We linked several health care databases to evaluate the proportion of ophthalmologists who exclusively provided cataract surgery (and no other ophthalmologic surgery) and the proportion who provided other types of ophthalmologic surgical care. To further investigate surgical focus, we evaluated the proportion of surgical cases within each surgical area for each ophthalmologist.Between 1994 and 2016, the proportion of ophthalmologists who exclusively provided cataract surgery rose from 10.0% to 34.9% (p0.0001). In contrast, the proportions of ophthalmologists providing other types of subspecialized surgical care were stable over the study period. Cataract surgeons showed high degrees of focus with a median percentage of surgical cases approaching 100% in all years. Among exclusive cataract surgeons, the median annual cataract case volume increased from 138 (interquartile range: 87-214) to 529 (interquartile range: 346-643) between 1994 and 2009 (p0.0001) and then plateaued.Between 1994 and 2016, exclusive cataract surgical focus among ophthalmologists in Ontario rose dramatically from 1 in 10 to 1 in 3 surgeons. This evolution was similar among recent graduates and established ophthalmologists. Our data may have important implications for policies regarding surgeon human resources as well as residency and fellowship training programs.

Purpose Tamsulosin is associated with intraoperative floppy iris syndrome (IFIS), an important risk factor for complications during cataract surgery. Significant efforts have been made to increase awareness of the risks associated with tamsulosin, and educational initiatives have fostered the uptake of technical adjustments to decrease adverse event rates among tamsulosin-exposed patients. However, the effectiveness of these efforts at the population level has not been studied. Design Population-based study to evaluate cataract surgical adverse event rates over time among patients exposed to tamsulosin and those not exposed to this drug. Participants All male patients 66 years of age and older undergoing cataract surgery in Ontario, Canada, between January 1, 2003, and December 31, 2013, were included in the study. Methods Linked healthcare databases were used to study the evolution in the risk of cataract surgical adverse events over time among tamsulosin-exposed and non–tamsulosin-exposed patients adjusting for patient-, surgeon-, and institution-level covariates. The study timeframe incorporated periods before and after the first reports of tamsulosin-associated IFIS. Main Outcome Measures Four important cataract surgical adverse events were evaluated: posterior capsule rupture, dropped lens fragments, retinal detachment, and suspected endophthalmitis. Results Among patients exposed to tamsulosin, the risk of surgical adverse events decreased over time (odds ratio, 0.95 per year; 95% confidence interval, 0.91–0.99 per year). This trend was observed across patient age strata. Among patients not recently exposed to tamsulosin, the risk of surgical adverse events also decreased over time (odds ratio, 0.96 per year; 95% confidence interval, 0.95–0.98 per year). Conclusions The risk of cataract surgical complications among both tamsulosin-exposed and non–tamsulosin-exposed patients declined between 2003 and 2013. Tamsulosin remains an important risk factor for cataract surgical adverse events, and ongoing efforts will be needed to develop and disseminate surgical approaches that mitigate the risks posed by tamsulosin.

Purpose Reports have questioned the technical proficiency of newly graduating surgeons. However, objective data supporting these concerns are limited. Surgical outcomes among recent graduates are an important indicator of residency programs' ability to graduate surgeons who are ready to meet the needs of their patients. This study aimed to investigate the association between a surgeon's number of years of independent practice and the risk of surgical adverse events. Design Population-based cohort study. Participants All patients 66 years of age or older undergoing isolated cataract operations in Ontario, Canada, between January 1, 1997, and December 31, 2013. Methods Cataract surgical outcomes for all operations performed by surgeons commencing practice in the study period were evaluated using linked health care databases. Main Outcome Measures Four serious complications were evaluated: posterior capsule rupture, dropped lens fragments, retinal detachment, and suspected endophthalmitis. Analyses controlled for patient-, surgeon-, and institution-level covariates. Results The study evaluated 1 431 320 cataract operations. Surgeons in their first year of independent practice were more than 9 times more likely to have high complication rates (≥2%) than surgeons in their tenth year (odds ratio [OR], 9.3; 95% confidence interval [CI], 2.7–31.9). Each additional year of independent practice was associated with a 10% decrease in the risk of patients experiencing an adverse surgical event (OR, 0.90 per year of surgeon independent practice; 95% CI, 0.87–0.94). Conclusions In this population-based study, surgical complications were significantly more likely early in surgeons' careers. Interventions may be needed in postgraduate surgical training and early independent career monitoring and mentoring processes to ensure patient safety while continually renewing the surgical workforce.

Objective To report on patterns of optometry prescribing and adherence to prescribing regulations at a tertiary care ophthalmology centre. Design Prospective cohort study. Participants All new referrals from optometrists and other health care professionals to the emergency eye care service (n = 1965) between July 2011 and June 2012, as well as optometry referrals to 2 subspecialty services (glaucoma [n = 71] and cornea [n = 212]). Methods In our primary analysis, the frequency of prescribing and classes of medications prescribed were reported and compared amongst various referral sources to the emergency eye care service. As a secondary analysis, we reported frequency of prescribing in optometry referrals to 2 subspecialty clinics. Adherence to prescribing guidelines was reported for all optometry referrals. Results Of 296 referrals from optometrists to the emergency eye care service, 20 (6.8%) had received a prescription medication; this was significantly less compared to emergency and family physicians ( p Conclusions After the introduction of prescribing privileges, optometrists prescribe a variety of medications in their practices. Current prescribing guidelines are not always followed in practice, suggesting that continued study and collaboration is necessary to create an optimal model of interdisciplinary care that provides access to the highest quality of care.

Vitamin D has emerged as a potentially important molecule in ophthalmology. To date, all ophthalmic data pertaining to vitamin D has been restricted primarily to tear and serum analysis in human patients. Considering the isolated nature of the eye, we sought to determine the presence of intraocular vitamin D in ocular disease. Methods 25-Hydroxyvitamin D3 (25(OH)D3) concentrations were measured in the eye and blood of 120 participants undergoing ophthalmic procedures. Ocular localization of the 1,25-dihydroxyvitamin D3-generating (CYP27B1) and deactivating (CYP24A1) hydroxylases was performed by immunohistochemistry. Gene expression of CYP27B1, CYP24A1 and VEGF-A was measured in eyes from patients with and without disease. Results 25(OH)D3 was quantified in 112 ocular samples. In 40 cataract patient samples, the average 25(OH)D3 concentration was 0.057 ng/mL, compared to 72 retinal disease patient samples, average of 0.502 ng/mL (p Conclusions Our data confirms that vitamin D is present in the humours of the human eye and that local synthesis/degradation is possible via the ocular CYP27B1 and CYP24A1. This argues for a functional role for local vitamin D production and signaling in the eye and suggests that vitamin D may be an important intraocular mediator in disease pathogenesis.

Purpose To investigate the effect of anti-inflammatory therapy on selective laser trabeculoplasty (SLT) outcomes. Design Randomized, double-masked, placebo-controlled trial. Participants Patients with primary open-angle or pseudo-exfoliation glaucoma. Methods Patients undergoing SLT were randomized to receive placebo (artificial tears), prednisolone acetate 1%, or ketorolac tromethamine 0.5% eye drops 4 times per day for 5 days commencing immediately after SLT. Main Outcome Measures Change in intraocular pressure (IOP) from baseline to the 1-month post-SLT visit. Results Mean change in IOP at the 1-month primary outcome time point, as well as all other time points, was not significantly different among groups ( P = 0.99). Likewise, a repeated-measures, mixed-effects model did not find significant differences in IOP outcome at the 1-month time point ( P = 0.95). The IOP was reduced in all groups at the 1-month post-SLT time point and all other time points, and no significant differences were found between groups using separate unadjusted cross-sectional analyses of variance ( P > 0.15 for analyses at all time points). Treatment failure rates were not different among groups ( P = 0.75), and at 1 year after SLT, the percentage of patients maintaining a 20% IOP reduction ranged from 18% to 22% in the 3 study groups. Conclusions Anti-inflammatory therapy after SLT does not seem to substantially influence the IOP-lowering effect of SLT. In this study of patients with low baseline IOP, SLT showed limited efficacy in achieving a sustained reduction in IOP.

Purpose To evaluate trends in glaucoma surgery subspecialization. Design Population-based analysis of incisional glaucoma surgery and laser trabeculoplasty practice patterns among all ophthalmologists in Ontario, Canada, from 1995 through 2010. Participants All ophthalmologists in Ontario, Canada, providing universal health care for the provincial population of approximately 12 million. Methods The province of Ontario provides government-funded universal health care insurance to all citizens through the Ontario Health Insurance Plan (OHIP). Anonymized physician services data were obtained from the OHIP database, which has excellent accuracy for procedure performance. Main Outcome Measures Proportion of ophthalmologists providing incisional glaucoma surgery and laser trabeculoplasty and the distribution of these surgical and laser procedures among ophthalmologists. Results Between 1995 and 2010, the median number of ophthalmologists in Ontario was 427 (35.1 per 1 million population), ranging from 417 to 453 (32.9–40.3 per 1 million population). The percentage of ophthalmologists providing incisional glaucoma surgery dropped from 35% in 1995 to 19% in 2010, a 47% decline. Over the same period, the mean number of incisional glaucoma surgeries performed per surgeon doubled, and the percentage of incisional glaucoma operations provided by high-volume surgeons rose from 23% to 59%. The percentage of ophthalmologists performing laser trabeculoplasty was relatively stable (48% in 1995 to 50% in 2010). Conclusions Over the past 16 years, the proportion of ophthalmologists providing incisional glaucoma surgery has declined significantly. At the same time, the proportion of incisional glaucoma surgery provided by high-volume glaucoma surgeons has more than doubled. These trends will have important implications for stakeholders from policy makers and hospitals to academic departments and residency education programs. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

This paper presents four three-dimensional (3D) micro-electrode arrays for pumping liquid by utilizing AC electro-osmosis (ACEO) mechanism. Fabricated by using PolyMUMPs(R) process, these electrode arrays are made of polysilicon and subject to a surface oxide layer, which does not exist on conventional gold electrodes. An ACEO finite element model (FEM) accounting for the surface oxide on polysilicon electrodes is integrated in this work. The relationship of the velocity of driven liquid vs. the frequency of the electrical driving signal is obtained for the four electrode arrays through simulation and testing. Impacts of the electrode configuration and surface oxide are analyzed by comparing simulation and experimental results.

To compare retinal nerve fibre layer (RNFL) thickness measurements acquired using spectral domain (SD) and time domain (TD) optical coherence tomography (OCT) systems.Prospective clinical study.Twenty eyes of 20 healthy volunteers.All patients underwent 3 sets of circular OCT scans around the optic disc using both a TD OCT system, and a new SD OCT system. RNFL thickness measures within each of 4 quadrants, as well as overall mean RNFL thickness, were compared. Bland-Altman plots were also used to assess agreement.Using the RTVue-100, RNFL measurements in the superior quadrant were, on average, 20 microm greater than those obtained from the Stratus (151.8 microm vs 131.7 microm, p0.0001). RNFL measures within other quadrants and overall mean RNFL thickness were not significantly different between systems. Bland-Altman plots indicated large differences between Stratus and RTVue-100 for all variables, with 95% limits of agreement spanning clinically important ranges of50 microm for all RNFL variables.Significant differences exist between RNFL measurements obtained from the TD and SD OCT systems used in this study. These related, but distinct, technologies are not interchangeable. Further studies will be required to allow for appropriate clinical use of new SD OCT systems.

RESUME Background: New laser and surgical techniques have had a significant effect on glaucoma therapy. A precise understanding of how these developments are affecting overall glaucoma management is fundamental to health services planning. The objective of this study was to synthesize Canadian national and provincial data regarding glaucoma laser and surgical procedure rates from 1992 to 2004. Methods: Canadian provincial health insurance databases, which cover virtually all surgical procedures provided domestically to Canadians, were accessed to ascertain yearly total glaucoma procedure numbers. To estimate the number of individuals with glaucoma, an age-stratified glaucoma prevalence model was applied to population census data. Results: Laser trabeculoplasty rates dramatically increased between 2001 and 2004 with the national Canadian rate more than doubling. However, this increase varied widely across regions, ranging from 0% to 530%. Trabeculectomy surgery rates slowly increased from 1992 to 1995, then declined by 29% nationally between 1995 and 2004. Implantation rates of glaucoma drainage devices increased 12-fold nationally between 1992 and 2004; by 2004 this procedure accounted for 10% of incisional glaucoma surgical procedures in Canada. Interpretation: In Canada, laser trabeculoplasty rates have risen significantly over recent years. Trabeculectomy rates have recently declined, and implantation of glaucoma drainage devices is playing an increasingly important role in glaucoma management in this country. Contexte : Les nouvelles techniques au laser et chirurgicales ont eu d'importants effets sur la therapie du glaucome. Pour la planification des services de sante, il est essentiel de comprendre precisement comment ces developpements affectent dans l'ensemble la gestion de la maladie. Cette etude a pour objet de faire la synthese des donnees canadiennes, nationales et provinciales, sur les taux des procedures au laser et chirurgicales de 1992 a 2004. Methodes : Les bases de donnees provinciales d'assurance-maladie, qui couvrent virtuellement toutes les procedures chirurgicales pratiquees au Canada, ont ete evaluees pour confirmer la somme annuelle des interventions pour le glaucome. Pour estimer le nombre de personnes atteintes du glaucome, on a applique aux donnees du recensement un modele de prevalence du glaucome stratifie par groupes d'âges. Resultats : Les taux de trabeculoplastie au laser ont augmente de facon spectaculaire entre 2001 et 2004, le taux a l'echelle nationale ayant plus que double. Toutefois, la hausse a varie considerablement entre les regions, s'etalant de 0 % a 530 %. Les taux de trabeculectomie ont augmente lentement de 1992 a 1995, puis, ils ont baisse de 29 % a l'echelle du pays entre 1995 et 2004. Les taux d'implantation des appareils de drainage pour le glaucome se sont multiplies par 12 au pays entre 1992 et 2004; en 2004, cette procedure comptait 10 % des chirurgies incisionnelles pour le glaucome au Canada. Interpretation : Au Canada, les taux de trabeculoplastie au laser ont augmente de facon signi- ficative ces dernieres annees. Les taux de trabeculectomie ont diminue et l'implantation d'ap- pareils de drainage du glaucome joue un role de plus en plus important dans la gestion du glaucome au pays.

To investigate the immediate and longer-term effect of ocular massage on intraocular pressure (IOP) after Ahmed valve insertion.A retrospective chart review was undertaken of the effects of ocular massage in patients with inadequately controlled IOP after Ahmed valve surgery. During a 20-month period between January 2004 and August 2005, 20 of 52 patients underwent a course of ocular massage. They were compared on IOP and the number of ocular hypotensive medications required with the 32 patients whose IOP was satisfactory after surgery.The mean time to initiation of massage was 29 days (range 8-141 days), and the mean total duration of massage was 127 days (range 18-273 days). At the initiation of massage, the mean IOP was 19.2 mm Hg, significantly higher than at any other postoperative visit (p = 0.001-0.02). Immediately following massage, the IOP was reduced by 40% to 11.6 mm Hg (p0.001). When compared with those patients not requiring massage, there were no differences in IOP at any subsequent visit (p = 0.1-0.9). There were also no differences in final absolute IOP reduction (11.1 [SD 5.9] for the massage group vs. 10.64 [SD 8.0] mm Hg for those not requiring massage, p = 0.8), percentage IOP reduction (46% vs. 40%, p = 0.5), or number of glaucoma medications required at 1 year (2.9 vs. 2.6, p = 0.4), respectively. The massage group was receiving more medications than the group not requiring massage at 3 months (3.1 vs. 1.9) and 6 months (3.5 vs. 2.2). No complications arose due to ocular massage.This is the first report to document that ocular massage is a safe and effective manoeuvre for the management of elevated IOP after Ahmed valve insertion. Massage resulted in an immediate reduction of IOP, and, despite initial higher postoperative IOP in the massage group, there were no differences between groups at 1 year with regard to IOP reduction or requirements for medications.

Alginates are versatile biopolymers used extensively in the food, textile and pharmaceutical industries. One of the major uses is in the treatment of reflux disease and here we investigate whether alginates can influence pepsin activity, a major aggressor in reflux disease. The primary uronic acid structure of alginates can be altered using epimerase technology and we test tailor-made alginates to identify the optimal structure for pepsin inhibition. Pepsin activity in the presence of alginates was studied using an in vitro N-terminal assay and enzyme kinetics using a chromagenic peptide. The data described showed clearly that alginates were capable of concentration dependently reducing the activity of pepsin in a non-competitive manner, in vitro. This was variable between different alginates of wide ranging structure and size with positive correlation with alternating sequences of mannuronic and guluronic acid. We hypothesize that alginates may have a more extensive role in the treatment of reflux disease by inhibiting pepsin, a damaging component of the refluxate.

The middle–late Campanian was marked by an increase in the bioprovinciality of calcareous microfossil assemblages into distinct Tethyan, Transitional, and Austral Provinces that persisted to the end of the Maastrichtian. The northwestern Australian margin belonged to the Transitional Province and the absence of key Tethyan marker species such as Radotruncana calcarata and Gansserina gansseri has led petroleum companies operating in the area to use the locally developed KCCM integrated calcareous microfossil zonation scheme. The KCCM zonation is a composite scheme comprising calcareous nannofossil (KCN), planktonic foraminiferal (KPF) and benthonic foraminiferal (KBF) zones. This paper presents the definitions and revisions of Zones KCCM8–19, from the highest occurrence (HO) of Aspidolithus parcus constrictus to the lowest occurrence (LO) of Ceratolithoides aculeus, and builds on our previous early–late Maastrichtian study. The presence of a middle–upper Campanian disconformity is confirmed by microfossil evidence from the Vulcan Sub-basin, Exmouth and Wombat plateaus, and the Southern Carnarvon Platform. In the Vulcan Sub-basin and on the Exmouth Plateau (ODP Hole 762C) the hiatus extends from slightly above the LO of common Rugoglobigerina rugosa to above the LO of Quadrum gothicum. On the Wombat Plateau (ODP Hole 761B) it spans from above the LO of Heterohelix semicostata to above the LO of Quadrum gothicum; and in the Southern Carnarvon Platform the disconformity has its longest duration from above the HO of Heterohelix semicostata to above the LO of Quadrum sissinghii. A significant revision of the events which define Zones KCCM18 and 19 was necessary owing to the observation that the LO of Ceratolithoides aculeus occurs below the HOs of Archaeoglobigerina cretacea and Stensioeina granulata incondita and the LO of common Rugoglobigerina rugosa. In the original zonation these events were considered to be coincident.

Bathymetric change is investigated within the transgressive phase of an extensive Early Cretaceous (Aptian-Albian) marine flooding of the Australian continent. Lithofacies and biofacies associations, found in nine outcrop sections and four continuously cored bore sections in the northeastern Eromanga Basin, are used to reconstruct depositional environments and to determine palaeobathymetry. Shoreface (c . 0–2 m water depth), transitional (c .

In the presence of pipecolate, Pseudomonas putida P2 (ATCC 25571) converts α-amino[6-14C]adipate to radioactive glutamate with a 14C distribution of 11% and 80% in carbons 1 and 5, respectively. This labeling pattern, when considered with previous data, indicates that α-aminoadipate is an obligate intermediate in the metabolism of pipecolate to glutamate. Some of the 14C in carbon 1 results from tricarboxylic acid cycle activity since cells incubated in the presence of malonate form glutamate with only 5.6% 14C in carbon 1. Cells incubated with dl-[2-14C]pipecolate form [1-14C]glutamate, which distinguishes between two possible pathways for pipecolate catabolism. While this data excludes glutarate as an intermediate in the metabolism of pipecolate to glutamate, dl-α-amino[6-14C]adipate forms radioactive glutarate and [1,5-14C]glutarate forms [1,5-14C]glutamate. From these results and earlier studies it is concluded that the major pathway for l-pipecolate catabolism in P. putida P2 is different from that in mammals. A proposed pathway includes enzyme-bound, or derivatives of, glutarate, glutaconate, and α-hydroxyglutarate as intermediates. The pathway for formation of radioactive glutarate from dl-α-amino[6-14C]adipate is unknown but could represent a minor contribution by a second catabolic pathway. Radioactive glutamate formed from [1,5-14C]glutarate containing 14C in carbon 1 is evidence for a glutarate catabolic route different from that inferred for Pseudomonas fluorescens and mammalian tissue.