[1] Univ British Columbia, Dept Ophthalmol & Visual Sci, Dept Ophthalmol, Vancouver, BC, Canada
[2] UCL, Inst Ophthalmol, London, England
[3] UCL, Med Phys & Biomed Engn, London, England
[4] Univ British Columbia, Fac Med, Vancouver, BC, Canada
[5] Simon Fraser Univ, Fac Appl Sci, Engn Sci, Burnaby, BC, Canada