title: CHOROIDAL VASCULARITY INDEX: A Novel Optical Coherence Tomography Based Parameter in Patients With Exudative Age-Related Macular Degeneration.
abstract: OBJECTIVE
  To evaluate choroidal structural changes in exudative age-related macular degeneration (AMD) using choroidal vascularity index computed from image binarization on spectral domain optical coherence tomography with enhanced depth imaging.
  
  
  METHODS
  This prospective case series included 42 consecutive patients with unilateral exudative AMD. Choroidal images were segmented into luminal area and stromal area. Choroidal vascularity index was defined as the ratio of luminal area to total choroid area. Mean choroidal vascularity index and mean choroidal thickness between study and fellow eyes of the same patient with dry AMD were compared using Student's t-test.
  
  
  RESULTS
  There was a significantly lower choroidal vascularity index in eyes with exudative AMD (60.14 ± 4.55 vs. 62.75 ± 4.82, P < 0.01). Luminal area (P < 0.01) was decreased in eyes with exudative AMD but there was no significant difference in total choroid area (P = 0.05) and choroidal thickness (P = 0.93) between study and fellow eyes.
  
  
  CONCLUSIONS
  Eyes with exudative AMD demonstrated reduced choroidal vascularity index but insignificant differences in choroidal thickness compared with their fellow eyes. Choroidal vascularity index may be a potential noninvasive tool for studying structural changes in choroid and monitoring choroidal disease in exudative AMD.
authors.affiliation: *National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore, Singapore; †Singapore Eye Research Institute, Singapore, Singapore; and ‡Singapore National Eye Centre, Singapore, Singapore.
authors.forename: Xin
authors.initials: X
authors.lastname: Wei
authors.forename: Daniel Shu Wei
authors.initials: DSW
authors.lastname: Ting
authors.forename: Wei Yan
authors.initials: WY
authors.lastname: Ng
authors.forename: Neha
authors.initials: N
authors.lastname: Khandelwal
authors.forename: Rupesh
authors.initials: R
authors.lastname: Agrawal
authors.forename: Chui Ming Gemmy
authors.initials: CMG
authors.lastname: Cheung
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002829:Choroid / Q000098:blood supply*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012171:Retinal Vessels / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000379:methods*; D014792:Visual Acuity; D057135:Wet Macular Degeneration / Q000175:diagnosis*