Population prevalence of tilted optic dik and the relationhip of thi ign to refractive error

PURPOE: To ae the prevalence of tilted dik and it aociation with refractive error and viual field defect. DEIGN: Population-baed cohort tudy. METHOD: The Blue Mountain Eye tudy examined urban Autralian aged 49 year or older between 1992–1994. Of 4,433 eligible participant, 3,654 (82.4%) participated. The eye examination included logMAR viual acuity, tandardized refraction, cover teting, tereocopic optic dik photography, and Humphrey automated perimetry. Inferior or naal optic dik tilting wa graded from tereocopic photograph. REULT: Of 3,583 participant with gradable photograph, inferior or naal optic dik tilting wa oberved in 77 eye of 56 participant (1.6%). The prevalence of tilted dik increaed from 0.4% in eye with atigmatim < 1.0 diopter to 17.9% in eye with atigmatim ≥ 5.0 diopter. The mean atigmatic error wa 2.2 diopter in eye with tilted dik compared with 0.7 diopter in eye with normal dik appearance, P < .001. Myopia wa preent in 66.2% of eye with tilted dik compared with 12.4% of eye with a normal dik appearance, P < .001. The mot common aociated feature were atigmatim (93.5%), pallor, and teellation of the adjacent chorioretinal tiue (74.0%), itu inveru of the retinal veel (70.1%), β-peripapillary atrophy (64.9%), trabimu (30.4%), viual field defect (19.4%), poterior taphyloma (18.2%), inferonaal pigmentary accumulation (9.1%), and chorioretinal atrophy (5.2%). uperotemporal (33.3%) and uperior (25.0%) viual field defect were mot frequent. CONCLUION: A tilted dik appearance wa not a rare finding in our tudy population and wa trongly aociated with atigmatim and higher level of pherical refractive error, particularly myopia. The tilted dik and it aociated viual field defect hould be ditinguihed from other initer caue.