title: [Evaluation the value of Pentacam arterial segment analysis system in the study of anterior segment of the eye before and after laser periphery iridectomy].
abstract: OBJECTIVE
  To evaluate the anterior segment parameters in early primary angle-closure glaucoma (PACG) and primary angle closure (PAC) eyes before and after neodymium:yttrium aluminum garnet (Nd:YAG) laser periphery iridectomy (LPI) by using Pentacam system.
  
  
  METHODS
  Self-control study. Sixty one eyes of 33 patients were recruited into this study. The images of the anterior segment of the eye were captured and the parameters [i.e. the anterior chamber (AC) volume, the central AC depth, the peripheral AC depth, the peripheral AC angle and the pupil size] were measured by the Pentacam system pre-operatively and 1 week after laser treatment.
  
  
  RESULTS
  The Pentacam system clearly showed the structure changes of the anterior segment after LPI (i.e. the convex configuration of the iris was flattened and the peripheral AC depth was deepened). The average AC volume (t=15.928), the peripheral AC depth (t=-17.399, -10.629, -12.576, -14.474) and the peripheral AC angle (t=-5.087) were increased significantly (P<0.01) after LPI. The AC volume was (74.10±16.35) mm3 before LPI and (94.10±18.42) mm3 after LPI, and the increases of peripheral AC depth were 0.17 mm (nasal) and 0.29 mm (temporal). There was no statistical significant changes in the AC depth before and after LPI.
  
  
  CONCLUSIONS
  In patients with PACG and PAC, the changes of AC after LPI can be demonstrated by the Pentacam qualitatively and quantitatively.
authors.affiliation: Department of Ophthalmology, People's Hospital Peking University, Beijing 100044, China.
authors.forename: Hui-juan
authors.initials: HJ
authors.lastname: Wu
authors.forename: Ze-qin
authors.initials: ZQ
authors.lastname: Ren
authors.forename: Yong-zhen
authors.initials: YZ
authors.lastname: Bao
authors.forename: Xian-ru
authors.initials: XR
authors.lastname: Hou
authors.forename: Yi-wen
authors.initials: YW
authors.lastname: Hu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000869:Anterior Eye Segment / Q000000981:diagnostic imaging* / Q000601:surgery*; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000601:surgery; D006801:Humans; D032801:Iridectomy / Q000379:methods*; D007498:Iris / Q000601:surgery; D053685:Laser Therapy / Q000379:methods; D008297:Male; D008875:Middle Aged; D011859:Radiography; D041623:Tomography, Optical Coherence