Economic appraisal of prosthetic replacement of ocular surface ecosystem in Canada

Published:October 01, 2021DOI:



      To perform an economic appraisal of the Prosthetic Replacement of Ocular Surface Ecosystem (PROSE; BostonSight, Needham Heights, Mass.) lens in patients with a distorted corneal surface or ocular surface disease in Canada.


      Retrospective observational cohort study with cost, cost-utility, and benefit-cost analyses.


      Patients who received PROSE from the only PROSE clinic in Canada from 2018 to 2020.


      Visual acuity (VA) outcomes of the participants were assessed. Benefits were defined as VA improvements that were converted into utilities and then quality-adjusted life years. Economic values were derived via government statements, clinic financial statements, and published literature.


      Average best-corrected VA (BCVA) improvement was –0.42 ± 0.41 logMAR (p = 2.68 × 10–13) or Snellen 20/53 for the overall cohort, –0.51 ± 0.48 (p = 5.42 × 10–8) or Snellen 20/65 for distorted corneal surface patients, and –0.31 ± 0.30 (p = 1.30 × 10–7) or Snellen 20/41 for ocular surface disease patients. This corresponded to discounted quality-adjusted life year gains of 0.51, 0.65, and 0.42, respectively, over an estimated 5-year PROSE device lifespan. Average cost to fit a patient with PROSE was USD$5 469.85 (CAD$7 087.28), of which USD$4 971.38 (CAD$6 441.42) was clinic cost and USD$498.47 (CAD$645.87) was patient cost. Cost-utility was USD$10 256.47 (CAD$13 289.31) for the overall cohort, USD$8 439.79 (CAD$10 935.44) for distorted corneal surface patients, and US$13 069.90 (CAD$16 934.67) for ocular surface disease patients. The benefit-cost ratio was 34.4 for all, 43.8 for distorted corneal surface patients, and 28.3 for ocular surface disease patients.


      Our economic appraisal demonstrated that PROSE treatment provides a significant, cost-effective benefit to Canadian patients with distorted corneal surfaces and ocular surface diseases. This indicates that PROSE clinics are an efficient investment.
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