title: Anterior-segment morphology and corneal biomechanical characteristics in pigmentary glaucoma.
abstract: OBJECTIVE
  The aim of the study reported here was to evaluate characteristics of the anterior-segment via anterior-segment optical coherence tomography (AS-OCT) and corneal biomechanical properties using an ocular response analyzer and their changes by peripheral laser iridotomy (PI) in patients with pigmentary glaucoma (PG).
  
  
  METHODS
  Seventeen eyes with PG were included consecutively. AS-OCT and ocular response analyzer measurements were taken before and 3 months after PI. Baseline morphology and change in morphology were analyzed by correlation and multiple linear regression analysis. The main parameters assessed were anterior-chamber (AC) angles and volume as well as corneal hysteresis (CH) and corneal resistance factor.
  
  
  RESULTS
  AC angles were found to have decreased significantly in each quadrant after PI (P<0.001), with the highest effect seen in the temporal quadrant, which decreased from 57.0°±9.6° to 44.1°±5.2° (± standard deviation). Mean AC volume decreased significantly from 213.1±36.4 to 187.0±23.4 mm(3) (P<0.001). CH and corneal resistance factor did not change after PI. CH was found to correlate with the preoperative superior and inferior angle width (Spearman's rho 0.553 and 0.615, respectively, P<0.05). Biomechanical parameters showed no predictive value on the change of AC angles or volume.
  
  
  CONCLUSIONS
  PI in eyes with PG results in a highly significant reduction in the AC angles and volume as visualized by AS-OCT, with the largest effect seen in the temporal quadrant. CH is strongly positively correlated with the superior and inferior preoperative AC angles, emphasizing the importance of the biomechanical properties of the cornea for glaucoma pathogenesis in PG, but corneal biomechanical properties cannot predict PI-related AC changes.
authors.affiliation: Department of Ophthalmology, University of Munich Hospital, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Annemarie
authors.initials: A
authors.lastname: Klingenstein
authors.affiliation: Department of Ophthalmology, University of Munich Hospital, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Kernt
authors.affiliation: Department of Ophthalmology, University of Munich Hospital, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Seidensticker
authors.affiliation: Department of Ophthalmology, University of Munich Hospital, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Anselm
authors.initials: A
authors.lastname: Kampik
authors.affiliation: Department of Ophthalmology, University of Munich Hospital, Ludwig-Maximilians University, Munich, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Hirneiss
keywords: anterior-segment optical coherence tomography; corneal hysteresis; ocular response analyzer