Introduction: Refractive surgery in presbyopia tends to achieve spectacle independence with minimal optical disturbances. We compared monovision to multifocality procedures regarding these outcomes.
Methods: We conducted a systematic review of published (till November 21, 2016) randomized controlled trials (RCTs) comparing any monovision to any multifocality method or comparing different monovision/multifocality methods to each other that enabled direct or indirect comparisons between particular monovision and particular multifocality procedures in presbyopic patients undergoing cataract-related or unrelated surgery in respect to spectacle independence, unaided binocular visual acuity (VA), contrast sensitivity (CS), and adverse events.
Results: Three trials comparing monovision (monofocal lenses, LASIK) to multifocal intraocular lenses (MFIOLs; Isert refractive or Tecnis diffractive) and 6 comparing other MFIOLs to Tecnis were included (1-12 months duration). Spectacle independence. All reporting trials were of sufficient quality. Directly, pseudophakic monovision was inferior to Isert (1 trial, N = 75, RR = 0.49, 95% CI 0.28-0.80) and Tecnis (1 trial, N = 211, RR = 0.36, 95% CI 0.25-0.52) in cataract patients, and LASIK was comparable to Tecnis (1 trial, N = 100, RR = 0.93, 0.78-1.10) in refractive surgery. In network meta-regression (6 trials, 14 arms) pseudophakic monovision in cataract patients was inferior to Tecnis. Indirect data suggest also that it is inferior (ReZoom refractive, TwinSet diffractive) or tends to be inferior (Array refractive) to other MFIOLs. LASIK was comparable to Tecnis in refractive surgery. Indirect data suggest also that it tends to superiority vs. ReZoom or Array refractive MFIOLs. Adverse events. No pooling was possible (heterogeneity of assessment and reporting). One quality direct RCT indicated less glare/dazzle with pseudophakic monovision vs. Tecnis in cataract patients. Unaided VA and CS data were burdened with heterogeneity (assessment, reporting) and insufficient quality.
Conclusions: Randomized comparisons of monovision to multifocality are scarce. Existing estimates regarding spectacle independence (imprecision, indirectness) and particularly regarding unaided VA and CS (assessment/reporting heterogeneity, bias, imprecision, indirectness) are burdened with uncertainty. Dysphotopsia is less common with monovision, but estimate uncertainty is high (bias, imprecision).
Keywords: Meta-analysis; Ophthalmology; Presbyopia; Refractive surgery; Systematic review.