Cost-effectiveness analysis of confocal scan laser ophthalmoscope (HRT II) versus GDX for diagnosing glaucoma

Purpose: The aim of this study was to assess the cost-effectiveness of confocal scan laser ophthalmoscopy (HRT II) and compare it with scanning laser polarimetry (GDx) for diagnosing glaucoma. Methods: A cost-effectiveness analysis was performed at two eye hospitals in Iran. The outcome was measured as the proportion of correctly diagnosed patients based on systematic review and Meta analysis. Costs were estimated at two hospitals that used the HRT II (Noor Hospital) and current diagnostic testing technology GDx (Farabi Hospital) from the perspective of the healthcare provider. The incremental cost-effectiveness ratio (ICER) was estimated on the base scenario. Results: Annual average costs were estimated as 12.70 USD and 13.59 USD per HRT II and GDx test in 2012, respectively. It was assumed that 80 of the maximum feasible annual tests in a work shift would be performed using HRT II and GDx and that the glaucoma-positive (Gl+) proportion would be 56 in the referred eyes; the estimated diagnostic accuracies were 0.753 and 0.737 for GDx and HRT II, respectively. The incremental cost-effectiveness ratio (ICER) was estimated at USD44.18 per additional test accuracy. In a base sensitivity sampling analysis, we considered different proportions of Gl+ patients (30-85), one or two work shifts, and efficiency rate (60-100), and found that the ICER ranged from USD29.45to USD480.26, the lower and upper values in all scenarios. Conclusion: Based on ICER, HRT II as newer diagnostic technology is cost-effective according to the World Health Organization threshold of <1 Gross Domestic Product (GDP) per capita in Iran in 2012 (USD7228). Although GDx is more accurate and costly, the average cost-effectiveness ratio shows that HRT II provided diagnostic accuracy at a lower cost than GDx. © 2015 Iranian Society of Ophthalmology

Confocal scan laser ophthalmoscope for diagnosing glaucoma: A systematic review and Meta-analysis

This systematic review was performed to estimate the diagnostic accuracy of the confocal scanning laser ophthalmoscopy in diagnosing glaucoma. We did a sensitive electronic search to find relevant studies. Two reviewers independently screened relevant articles and extracted required data about study methods and reported results of sensitivity and specificity. A meta-analysis was conducted for pooling data to compare different editions of the Heidelberg Retina Tomograph (HRT) with one of its alternatives, scanning laser polarimetry (GDx) with the criteria of "visual field defect" and "changes of nerve fiber layer" as the reference standard. We identified 37 evaluations from 28 relevant primary studies. In these studies, 9573 eyes (4883 glaucomatous and 4689 non-glaucomatous) were assessed with regards to the reference standard using one of the HRT editions with or without GDx. Diagnostic odds ratios were 9.35 95% confidence interval (CI): 7.58-11.53 for HRT, 11.84 (95% CI: 9.97-14.06) for HRT II, 11.86 (95% CI: 9.16-15.35) for HRT III, and 21.33 (95% CI, 13.56-33.55) for GDx. Although GDx was more accurate than HRT, all editions of HRT had acceptable performance in diagnosing glaucomatous eyes with an ophthalmologist's clinical examination as the reference standard. © 2015 by Asia Pacific Academy of Ophthalmology