Publications (22)57.92 Total impact
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Article: Systemic effects of intravitreal vascular endothelial growth factor inhibitors.
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ABSTRACT: PURPOSE OF REVIEW: The development of vascular endothelial growth factor (VEGF) inhibitors has revolutionized the treatment of retinal diseases. However, VEGF functions in many physiological and pathological processes. Consequently, inhibition of this signalling molecule carries the potential to cause serious adverse events. RECENT FINDINGS: Numerous clinical trials, meta-analyses and population-based studies have provided data regarding the safety of intravitreal VEGF inhibitor injections. Although individual trials and some meta-analyses have not found significant risks, other meta-analyses have suggested possible risks, especially in patients with multiple baseline risk factors. Population-based studies have not found increased risks of vascular adverse events. SUMMARY: Overall, results across studies with differing methodologies provide some reassurance that the widespread use of intravitreal injections of VEGF inhibitors has not resulted in significant increases in the risks of adverse events. However, ongoing vigilance and further study remain priorities, with a particular need for greater evaluation of high-risk subgroups. Rapidly evolving treatment options for ocular diseases including new drugs and new delivery technologies will require ongoing evaluations of safety.Current opinion in ophthalmology 03/2013; · 2.49 Impact Factor -
Article: Projecting the growth of cataract surgery during the next 25 years.
Archives of ophthalmology 11/2012; 130(11):1479-81. · 3.86 Impact Factor -
Article: Subspecialization in Glaucoma Surgery.
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ABSTRACT: 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.Ophthalmology 07/2012; · 5.45 Impact Factor -
Article: Stroke rates after introduction of vascular endothelial growth factor inhibitors for macular degeneration: a time series analysis.
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ABSTRACT: To assess whether stroke rates among patients with retinal disease were influenced by the rapid and sequential uptakes of bevacizumab and ranibizumab for age-related macular degeneration (AMD). Population-based, time series analysis using encrypted, linked healthcare databases in Ontario, Canada. We included all patients aged 66 years or older with physician-diagnosed retinal disease in the previous 5 years between 2002 and 2010 (N = 116 388). A secondary analysis evaluated patients who had undergone photodynamic therapy (PDT) within the preceding year (N = 10 059). We used segmented regression analysis to evaluate changes in the rate of hospitalization for ischemic stroke associated with the introduction of bevacizumab and ranibizumab. The stroke rate was compared across 3 mutually exclusive periods: the period before the availability of bevacizumab or ranibizumab, the period of bevacizumab dominant AMD therapy, and the period of ranibizumab dominant AMD therapy. Hospitalizations for ischemic stroke. Among patients with retinal disease, neither the trend nor the level of the stroke time series changed with the uptake of bevacizumab (trend change coefficient -0.0026 stroke hospitalizations/1000 subjects/month [95% confidence interval {CI}, -0.0066 to 0.0014; P = 0.20]; level change coefficient, 0.036 stroke hospitalizations/1000 subjects [95% CI, -0.070 to 0.14; P = 0.51]), or ranibizumab (trend change coefficient: -0.0011 stroke hospitalizations/1000 subjects/month [95% CI, -0.0087 to 0.0065; P = 0.78]; level change coefficient: -0.017 stroke hospitalizations/1000 subjects [95% CI, -0.14 to 0.11; P = 0.79]). Similar results were observed in the analysis restricted to patients with recent PDT and in analyses stratified on age, sex, history of stroke, and history of diabetes. The rapid uptake of vascular endothelial growth factor (VEGF) inhibitors for AMD was not associated with a change in the rate of hospitalization for stroke among Ontario seniors with retinal disease. Furthermore, stroke rates in the bevacizumab and ranibizumab periods were not different. These population-level results complement the findings of a recently published trial comparing bevacizumab and ranibizumab, and may assist clinicians and policy makers as they balance the comparative efficacy, safety, and cost of these 2 closely related treatments.Ophthalmology 06/2012; 119(8):1604-8. · 5.45 Impact Factor -
Article: Short-term exposure to antidepressant drugs and risk of acute angle-closure glaucoma among older adults.
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ABSTRACT: Acute angle-closure glaucoma (AACG) is an ocular emergency that may be precipitated by certain types of medications. Antidepressant drugs can affect a number of neurotransmitters, which are involved in the regulation of the iris, which may precipitate AACG. We used a case-crossover study design to investigate the association between recent exposure to antidepressant drugs and AACG. We identified patients with AACG among adults aged 66 years or older between 1998 and 2010 in Ontario using linked population-based administrative databases. We identified intermittent users of antidepressant medications through prescription drug claims in the year preceding AACG. We determined antidepressant exposure in the period immediately before AACG and compared it with antidepressant exposure in 2 earlier control periods. We used conditional logistic regression to determine the odds ratio for antidepressant exposure in the hazard period compared with the control periods. A total of 6470 patients with AACG occurred during the study period. The mean age of the patients was 74.3 years, and 66% were female. Overall, 5.6% of individuals were intermittent users of antidepressant drugs in the year preceding AACG. The odds ratio for any antidepressant exposure in the period immediately preceding AACG was 1.62 (95% confidence interval, 1.16-2.26). An increased risk of AACG was also observed in several subgroups. We conclude that recent exposure to antidepressant drugs is associated with an increased risk of AACG. Clinicians should remain vigilant for the development of this uncommon but potentially serious adverse event after initiating antidepressant therapy.Journal of clinical psychopharmacology 04/2012; 32(3):403-7. · 5.09 Impact Factor -
Article: Implications of "not me" drugs for health systems: lessons from age related macular degeneration.
BMJ (Clinical research ed.). 01/2012; 344:e2941. -
Article: Variation in prices charged to patients for specialty intraocular lenses inserted during universally covered cataract surgery.
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ABSTRACT: Patients often pay for specialty intraocular lenses (IOLs) for cataract surgery covered by universal insurance. This practice creates the potential for inequitable pricing where the medical service provider is also the retailer. We measured the variation in prices between cataract surgeons for the same IOL and associated testing. We telephoned every cataract surgeon in Ontario, Canada, and asked their price for the most common type of specialty IOL as a prospective patient. We measured the total prices quoted and variation between providers. We contacted 404 ophthalmologists. There were 256 that performed cataract surgery but 127 offered the most commonly employed specialty IOL and would provide a price to patients over the telephone. We obtained prices from all 127 ophthalmologists. Prices for the same lens and associated testing varied substantially between ophthalmologists from $358 to $2790 (median $615, interquartile range $528-$915). There was variation in all components of the total out-of-pocket price, including the price for the IOL itself, charges for uninsured eye measurements, and non-specific supplemental fees. Although cataract surgery is covered by public health insurance, some ophthalmologists charge much more than others for the same specialty IOL and associated testing. Greater access to price information and better regulatory control could help ensure patients receive fair value for out-of-pocket health expenses.PLoS ONE 01/2012; 7(4):e35179. · 4.09 Impact Factor -
Article: Adverse events with intravitreal injection of vascular endothelial growth factor inhibitors: nested case-control study.
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ABSTRACT: To assess the risk of systemic adverse events associated with intravitreal injections of vascular endothelial growth factor inhibiting drugs. Population based nested case-control study. Ontario, Canada. 91,378 older adults with a history of physician diagnosed retinal disease identified between 1 April 2006 and 31 March 2011. Cases were 1477 patients admitted to hospital for ischaemic stroke, 2229 admitted for an acute myocardial infarction, 1059 admitted or assessed in an emergency department for venous thromboembolism, and 2623 admitted for congestive heart failure. Event-free controls (at a ratio of 5:1) were matched to cases on the basis of year of birth, sex, history of the outcome in the previous 5 years, and diabetes. MAIN EXPOSURE MEASURE: Exposure to vascular endothelial growth factor inhibiting drugs identified within 180 days before the index date. After adjustment for potential confounders, participants who had ischaemic stroke, acute myocardial infarction, congestive heart failure, or venous thromboembolism were not more likely than control participants to have been exposed to either bevacizumab (adjusted odds ratios of 0.95 (95% confidence interval 0.68 to 1.34) for ischaemic stroke, 1.04 (0.77 to 1.39) for acute myocardial infarction, 0.81 (0.49 to 1.34) for venous thromboembolism, and 1.21 (0.91 to 1.62) for congestive heart failure) or ranibizumab (adjusted odds ratios 0.87 (0.68 to 1.10) for ischaemic stroke, 0.90 (0.72 to 1.11) for acute myocardial infarction, 0.88 (0.67 to 1.16) for venous thromboembolism, and 0.87 (0.70 to 1.07) for congestive heart failure). Similarly, a secondary analysis of exclusive users of bevacizumab or ranibizumab showed no differences in risk between the two drugs (adjusted odds ratios for bevacizumab relative to ranibizumab of 1.03 (0.67 to 1.60) for ischaemic stroke, 1.23 (0.85 to 1.77) for acute myocardial infarction, 0.92 (0.51 to 1.69) for venous thromboembolism, and 1.35 (0.93 to 1.95) for congestive heart failure). These findings were consistent for all but one outcome in subgroup analyses. Intravitreal injections of bevacizumab and ranibizumab were not associated with significant risks of ischaemic stroke, acute myocardial infarction, congestive heart failure, or venous thromboembolism.BMJ (Clinical research ed.). 01/2012; 345:e4203. -
Article: New surgical technique for correcting tube-iris touch following glaucoma drainage implant surgery.
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ABSTRACT: Glaucoma drainage implant surgery may be associated with a number of potential complications including tube malpositioning. This malpositioning may have serious sequelae such as corneal endothelial damage, chronic iritis, cataract formation or tube occlusion. Traditional management of tube malpositioning involves major surgical re-dissection and reinsertion of the tube. Alternatively, shortening of the tube within the anterior chamber can, in some circumstances, relieve tube contact with the endothelium or iris. However, these procedures are associated with important risks. We describe a new minimally invasive surgical technique for correcting posterior tube malpositioning that avoids the need to shorten the tube or re-dissect the conjunctiva. This technique is straightforward to perform and has successfully maintained proper drainage device tube position during more than 1 year of follow up.Clinical and Experimental Ophthalmology 12/2010; 39(6):572-5. · 1.98 Impact Factor -
Article: Effect of physician remuneration fees on glaucoma procedure rates in Canada.
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ABSTRACT: Earlier studies have reported wide regional variability in glaucoma procedure rates, suggesting nonclinical factors influencing procedure rates. This study was designed to investigate the possible influence of fees on procedure rates. Databases were accessed to obtain yearly provincial population, procedure and ophthalmologist numbers, and physician fees for trabeculoplasties, trabeculectomies, and glaucoma drainage device (GDD) implantations from 1992 to 2007. Regression models using generalized estimating equation methods were used to evaluate the influence of fees on procedure rates after adjusting for temporal trends and the number of ophthalmologists per 1000 persons with glaucoma. Trends in glaucoma procedure rates and fees varied widely among provinces: decrease of 98% to an increase of 380% for trabeculoplasties, decrease of 72% to an increase of 42% for trabeculectomies, and decrease of 32% to an increase of 1292% for GDD. In 2007, provincial remuneration varied from $125 to $553 for trabeculoplasties, $370 to $748 for trabeculectomies, and $426 to $956 for GDD. The regression models found for every 1000 persons with glaucoma, a $100 increase in fee was associated with 0.68 more trabeculoplasties (P=0.94), 1.2 fewer trabeculectomies (P=0.17), and 0.18 more GDD implantations (P=0.18); and for every additional ophthalmologist per 1000 persons with glaucoma, 53.8 more trabeculoplasties (P=0.24), 0.34 more trabeculectomies (P=0.86), and 0.79 more GDD implantations (P=0.0004). A regression model examining procedure substitution effect did not find any association between relative remuneration and procedure rate. Our analysis did not show an influence of physician remuneration fee on procedure rates in Canada during the study period.Journal of glaucoma 11/2010; 20(9):548-52. · 1.74 Impact Factor -
Article: Rapid expansion of intravitreal drug injection procedures, 2000 to 2008: a population-based analysis.
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ABSTRACT: To evaluate patterns of care for age-related macular degeneration following the introduction of vascular endothelial growth factor inhibitors. Using a population-based retrospective design, we studied monthly fee claims for intravitreal injections submitted to the Ontario Health Insurance Plan between January 1, 2000, and March 30, 2008, and linked procedures to the physicians who performed them. This database records physician services provided as part of universal health care insurance coverage in Ontario, Canada. This program covers all residents of Ontario, which had an average population of 12.1 million during the study period. Following regulatory approval of bevacizumab for colorectal cancer in 2005, off-label use of this drug for the treatment of retinal disease, particularly age-related macular degeneration, became increasingly common. The rate of intravitreal injections in Ontario rapidly grew 8-fold, and this growth preceded the availability of ranibizumab by more than a year. Moreover, in 2007, more than 50% of intravitreal injections in Ontario were performed by 3% of ophthalmologists. The development of vascular endothelial growth factor inhibitors has revolutionized the treatment of age-related macular degeneration. To our knowledge, this study is the first to quantify the dramatic uptake of these treatments at a population level. Our findings also suggest that off-label injection of bevacizumab was highly prevalent in Ontario. Serial intravitreal injections requiring direct physician administration and the concentration of injection procedures in the hands of a small number of ophthalmologists have the potential to affect services for other vision-threatening conditions.Archives of ophthalmology 03/2010; 128(3):359-62. · 3.86 Impact Factor -
Article: Canadian health care: a question of access.
Archives of ophthalmology 10/2009; 127(10):1384-6. · 3.86 Impact Factor -
Article: Comparison of retinal nerve fibre layer measurements from time domain and spectral domain optical coherence tomography systems.
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ABSTRACT: 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, p< 0.0001). 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 of >50 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.Canadian Journal of Ophthalmology 10/2009; 44(5):562-6. · 1.47 Impact Factor -
Article: Internal glaucoma drainage device tube fenestration for uncontrolled postoperative intraocular pressure.
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ABSTRACT: To describe a novel approach to early postoperative intraocular pressure (IOP) control after glaucoma drainage device (GDD) implantation. Two patients with elevated IOP after GDD implantation underwent internal GDD tube fenestration using a 30-gauge needle to perforate the GDD tube. IOP was lowered in each case by over 50% without complication. Transanterior chamber internal GDD tube fenestration is a novel, straightforward approach to early IOP control after GDD implantation. This procedure adds to our armamentarium of methods for controlling IOP during the early postoperative period.Journal of glaucoma 10/2008; 17(6):494-6. · 1.74 Impact Factor -
Article: Timolol concentrations in breast milk of a woman treated for glaucoma: calculation of neonatal exposure.
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ABSTRACT: A 32-year-old lactating woman with open-angle glaucoma used timolol maleate 0.5% eye drops twice daily to her right eye for 6 months. Four milk samples were collected over a span of 6 days. Timolol maleate milk levels were examined by liquid chromatography tandem mass spectrometry and found to be at a mean of 0.12 ng/mL (range, 0 to 0.37 ng/mL). At this level, the theoretical maximum relative infant dose expressed as a percentage of the weight-adjusted maternal dose was 0.012%. As most glaucoma patients administer drops to both eyes, the dosage was duplicated to reflect the more pertinent calculated theoretical relative infant dose of 0.024%. This dose of timolol is unlikely to cause systemic side effects to the healthy breastfed infant.Journal of glaucoma 10/2008; 17(6):511. · 1.74 Impact Factor -
Article: Glaucoma laser and surgical procedure rates in Canada: a long-term profile.
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ABSTRACT: 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. 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. 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. 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.Canadian Journal of Ophthalmology 09/2008; 43(4):449-53. · 1.47 Impact Factor -
Article: Multicenter study of compliance and drop administration in glaucoma.
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ABSTRACT: Poor compliance with medication is a major concern in the management of glaucoma. Improper administration technique can lead to contamination and inaccurate dosing. This study estimates the prevalence and predictors of noncompliance and improper administration technique among Canadian glaucoma patients. Data were collected using a standardized questionnaire. Noncompliance was defined as missing at least 1 drop of medication per week and (or) the inability to accurately describe the medication regimen. Patients were asked to indicate the most common reason for missing medication. Study personnel assessed drop administration technique as patients were applying eye drops. Physicians provided information, including measures of disease stability, regarding the patient's glaucoma. Predictors were assessed using odds ratios from a logistic regression model. 500 patients from 10 centers across Canada participated in the study. Of these, 25.6% reported missing at least 1 drop of medication per week, and 4.2% were unable to accurately describe their medication regimen. The overall proportion of noncompliance was 27.9%. With regard to drop administration, 6.8% missed their eye and 28.8% contaminated the bottle tip; overall, 33.8% demonstrated improper technique. The most common reasons given for missing eye drops were "forgetfulness" and "being away from drops." Formal education limited to elementary school and treatment duration of <5 years increased patient-reported noncompliance. Factors associated with improper administration technique were age 60 years and older and formal education limited to elementary school. Over 50% of the patients surveyed were either noncompliant or demonstrated improper administration technique. Glaucoma patients should be educated on the importance of compliance and instructed on proper drop administration.Canadian Journal of Ophthalmology 08/2008; 43(4):454-61. · 1.47 Impact Factor -
Article: Ocular massage for intraocular pressure control after Ahmed valve insertion.
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ABSTRACT: 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 (p < 0.001). 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.Canadian Journal of Ophthalmology 03/2008; 43(1):48-52. · 1.47 Impact Factor -
Article: Short-term intraocular pressure changes after intravitreal injection of bevacizumab.
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ABSTRACT: This study examines the changes in short-term intraocular pressure (IOP) in patients receiving intravitreally administered bevacizumab. A prospective series of consecutive patients undergoing injection of intravitreal bevacizumab was investigated. All patients received bevacizumab (0.05 cc) injected intravitreally in a standard fashion. IOP was measured at baseline, 2, 5, and 30 minutes after injection by 1 of 2 observers using Goldman applanation tonometry. An intraobserver study was done to assess agreement in IOP measurements. We accrued 104 patients with a mean age of 76 years: 58% were female, and 42% were male. Most patients (85%) were being treated for neovascular age-related macular degeneration. The mean IOP values at baseline, 2, 5, and 30 minutes after injection were 14.0 (95% confidence interval [CI] 13.4-14.7) mm Hg, 36.1 (95% CI 33.5-38.6) mm Hg, 25.7 (95% CI 23.8-27.5) mm Hg, and 15.5 (95% CI 12.4-16.51) mm Hg, respectively. Three patients (2.9%) had an IOP of 25 mm Hg or higher at 30 minutes. IOP normalized within 2 hours without medical therapy in 2 of these patients, and 1 patient required a 1-week course of glaucoma medication. Regression analysis showed a trend towards phakic patients having higher IOP at 30 minutes (odds ratio = 3.2; p = 0.089). Intravitreal injection of bevacizumab is safe with respect to short-term IOP changes, as almost all patients' IOP returned to a safe range (<25 mm Hg) within 30 minutes. Elevated IOP at 30 minutes after injection does occur, rarely, thus clinicians should consider checking IOP after injection as a precaution. Transient extreme IOP elevations occur in a significant percentage of patients, but the consequences of these events are unknown.Canadian Journal of Ophthalmology 12/2007; 42(6):807-11. · 1.47 Impact Factor -
Article: Optimal optical coherence tomography-based measures in the diagnosis of clinically significant macular edema: retinal volume vs foveal thickness.
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ABSTRACT: To compare optical coherence tomography-based measures of retinal thickness and volume as quantitative tests for clinically significant macular edema (CSME). Diagnostic validation study. Sixty-five eyes with diabetic retinopathy underwent stereo photographic and optical coherence tomographic examination. Stereo photographs were examined in a masked fashion to determine the presence or absence of CSME according to criteria from the Early Treatment Diabetic Retinopathy Study. Optical coherence tomography-based measurements of central foveal thickness as well as retinal volumes within a series of radii of fixation were generated. The main outcome measures were areas under receiver operating characteristic curves. Likelihood ratios, sensitivities, and specificities for the diagnosis of CSME were also evaluated. Retinal volumes within radii of 0.50 mm and 1.11 mm of fixation and central foveal thickness were the best variables for discriminating between those with and without CSME as evidenced by analysis of receiver operating characteristic curves. There were no significant differences among these 3 variables in their performance as diagnostic tests for CSME. Optical coherence tomography-based retinal volume and central foveal thickness variables display comparable abilities to discriminate between those with and without CSME. Both measures may have clinical applications as quantitative diagnostic tests for CSME.Archives of Ophthalmology 06/2007; 125(5):619-23. · 3.71 Impact Factor
Top co-authors
Top Journals
Institutions
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2010–2012
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University of Toronto
- • Faculty of Medicine
- • Department of Ophthalmology and Vision Sciences
Toronto, Ontario, Canada
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2007–2010
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Queen's University
- Department of Ophthalmology
Kingston, Ontario, Canada
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2008
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The University of Western Ontario
London, Ontario, Canada
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