[1] Univ Exeter, Med Sch, St Lukes Campus, Exeter EX1 2HZ, England
[2] Royal Devon Univ Healthcare NHS Fdn Trust, West England Eye Unit, Exeter EX2 5DW, England
[3] Royal Devon Univ Healthcare NHS Fdn Trust, NDDH, Barnstaple EX31 4JB, England
[4] Moorfields Eye Hosp NHS Fdn Trust, 162 City Rd, London EC1V 2PD, England
[5] Med Univ Warsaw, SPKSO Ophthalm Univ Hosp, Dept Ophthalmol, PL-00576 Warsaw, Poland
[6] Med Univ Warsaw, Dept Histol & Embryol, PL-02004 Warsaw, Poland