title: Posterior (outward) migration of the lamina cribrosa and early cupping in monkey experimental glaucoma.
abstract: OBJECTIVE
  To quantify the lamina cribrosa insertion into the peripapillary sclera and optic nerve pia in normal (N) and early experimental glaucoma (EEG) monkey eyes.
  
  
  METHODS
  Perfusion-fixed optic nerve heads (ONHs) from 21 animals were digitally reconstructed three dimensionally and delineated. Anterior Laminar Insertion Position (ALIP), Posterior Laminar Insertion Position (PLIP), Laminar Insertion Length (LIL; distance between the anterior and posterior laminar insertions), and Scleral Thickness (at the Anterior Sub-arachnoid space) were calculated for each ONH. Animals were pooled into four groups based on the kill condition (N vs. EEG) and perfusion IOP (10, 30, or 45 mm Hg) of each eye: N10-N10 (n = 6), N30/45-N10 (n = 6), EEG10-N10 (n = 3), and EEG30/45-N10 (n = 6). Glaucomatous EEG versus N eye differences in each group and each animal were required not only to achieve statistical significance (P < 0.05) but also to exceed physiologic intereye differences within the bilaterally normal groups.
  
  
  RESULTS
  ALIP was significantly posterior (outward) in the EEG compared with N10 eyes of the EEG30/45-N10 group and 5 of 9 individual EEG eyes (difference range, 12-49 μm). PLIP was significantly posterior in the EEG eyes of both EEG groups and in 6 of 9 individual EEG eyes (range, 25-83 μm). LIL ranged from 90 to 190 μm in normal eyes and was significantly increased within the EEG eyes of both EEG groups and in 7 of 9 individual EEG eyes (difference range, 30-47 μm).
  
  
  CONCLUSIONS
  Posterior migration of the lamina cribrosa is a component of early cupping in monkey EEG.
authors.affiliation: Optic Nerve Head Research Laboratory, Devers Eye Institute, Legacy Health System, Portland, Oregon 97232, USA.
authors.forename: Hongli
authors.initials: H
authors.lastname: Yang
authors.forename: Galen
authors.initials: G
authors.lastname: Williams
authors.forename: J Crawford
authors.initials: JC
authors.lastname: Downs
authors.forename: Ian A
authors.initials: IA
authors.lastname: Sigal
authors.forename: Michael D
authors.initials: MD
authors.lastname: Roberts
authors.forename: Hilary
authors.initials: H
authors.lastname: Thompson
authors.forename: Claude F
authors.initials: CF
authors.lastname: Burgoyne
mesh_terms: D000818:Animals; D001369:Axons / Q000473:pathology; D002465:Cell Movement; D004195:Disease Models, Animal; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D007429:Intraocular Pressure; D008252:Macaca fascicularis; D008253:Macaca mulatta; D008297:Male; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D012590:Sclera / Q000473:pathology*; D014065:Tonometry, Ocular