title: Anterior chamber depth, iridocorneal angle width, and intraocular pressure changes after phacoemulsification: narrow vs open iridocorneal angles.
abstract: OBJECTIVE
  To determine the association of changes in anterior chamber angle and anterior chamber depth (ACD) with intraocular pressure (IOP) reduction after uncomplicated phacoemulsification.
  
  
  METHODS
  In this prospective study, subjects underwent phacoemulsification with foldable lens implantation. Anterior chamber angle grading of 2 or less (Shaffer grading) in 3 or all quadrants was considered narrow angle (NA). Anterior segment optical coherence tomography and tonometry were performed preoperatively and 10 days and 1, 3, and 6 months after surgery. The ACD and angle opening distance at 500 μm anterior to the scleral spur (AOD500) were assessed from anterior segment optical coherence tomography.
  
  
  RESULTS
  Data were collected from 63 eyes that underwent cataract surgery. Twenty-six eyes were classified as having NA. Before surgery, the mean (SD) AOD500 and ACD in the NA group were 0.179 (0.014) mm and 2.23 (0.07) mm, respectively. Six months after surgery, the mean (SD) AOD500 and ACD in the NA group were 0.389 (0.025) mm and 3.75 (0.05) mm, respectively. The postoperative IOP was reduced significantly in both groups. We found that each 0.1-mm increase in AOD500 corresponded to a mean (SD) 0.42 (0.18)-mm Hg decrease in IOP (P < .001) in the NA group and 0.32 (0.16) mm Hg (P = .046) in the OA group.
  
  
  CONCLUSIONS
  Postoperative reduction in IOP was proportional to the increase in angle in both groups, but the IOP reduction per 0.1-mm increase in AOD500 in NA eyes was greater than that in OA eyes.
authors: Department of Ophthalmology, San Francisco School of Medicine, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
authors: Guofu
authors: G
authors: Huang
authors: Eduardo
authors: E
authors: Gonzalez
authors: Pai-Huei
authors: PH
authors: Peng
authors: Roland
authors: R
authors: Lee
authors: Thidarat
authors: T
authors: Leeungurasatien
authors: Mingguang
authors: M
authors: He
authors: Travis
authors: T
authors: Porco
authors: Shan C
authors: SC
authors: Lin
mesh_terms: D000368:Aged; D000867:Anterior Chamber / Q000473:pathology*; D058452:Axial Length, Eye; D003315:Cornea / Q000473:pathology*; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D007498:Iris / Q000473:pathology*; D019654:Lens Implantation, Intraocular; D008297:Male; D009887:Ophthalmoscopy; D018918:Phacoemulsification; D011184:Postoperative Period; D011446:Prospective Studies; D041623:Tomography, Optical Coherence; D014065:Tonometry, Ocular