title: Peripapillary intrachoroidal cavitations. The Beijing eye study.
abstract: OBJECTIVE
  To assess prevalence, size and location of peripapillary intrachoroidal cavitations (PICCs) and their associations in a population-based sample. .
  
  
  METHODS
  The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 ± 9.8 years (range:50-93 years). A detailed ophthalmic examination included enhanced depth imaging of the choroid by spectral-domain optical coherence tomography and fundus photography. PICCs were defined as triangular thickening of the choroid with the base at the optic disc border and a distance between Bruch's membrane and sclera of ≥ 200 μm. Parapapillary large choroidal vessels were excluded.
  
  
  RESULTS
  Out of 94 subjects with high myopia (refractive error <-6.0 diopters or axial length >26.5mm in right eyes), OCT images were available for 89 (94.7%) participants. A PICC was detected in 15 out of these 89 highly myopic subjects (prevalence:16.9 ± 4.0%) and in none of hyperopic, emmetropic or medium myopic subgroups each consisting of 100 randomly selected subjects. Mean PICC width was 4.2 ± 2.3 hours (30°) of disc circumference and mean length was 1363 ± 384 μm. PICCs were located most frequently (40%) at the inferior disc border. On fundus photos, a typical yellow-orange lesion was found in 8 (53%) eyes with PICCs. In binary regression analysis, presence of PICCs was significantly associated with optic disc tilting (P=0.04) and presence of posterior staphylomata (P=0.046).
  
  
  CONCLUSIONS
  Prevalence of PICCs in the adult Chinese population was 16.9 ± 4.0% in the highly myopic group, with no PICCs detected in non-highly myopic eyes. PICCs were located most frequently at the inferior optic disc border. Only half of the PICCs detected on OCT images showed a yellow-orange lesion on fundus photos. Presence of PICC was significantly associated only with an increased optic disc tilting and presence of posterior staphylomata, while it was not associated with axial length, refractive error or other ocular or systemic parameters.
authors.affiliation: Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Science Key Laboratory, Beijing, China.
authors.forename: Qi Sheng
authors.initials: QS
authors.lastname: You
authors.forename: Xiao Yan
authors.initials: XY
authors.lastname: Peng
authors.forename: Chang Xi
authors.initials: CX
authors.lastname: Chen
authors.forename: Liang
authors.initials: L
authors.lastname: Xu
authors.forename: Jost B
authors.initials: JB
authors.lastname: Jonas
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D002829:Choroid / Q000473:pathology*; D015862:Choroid Diseases / Q000453:epidemiology / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D005654:Fundus Oculi; D006801:Humans; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000453:epidemiology / Q000473:pathology*; D015995:Prevalence; D041623:Tomography, Optical Coherence