title: Horizontal central ridge of the lamina cribrosa and regional differences in laminar insertion in healthy subjects.
abstract: OBJECTIVE
  To assess the general morphology and position of the lamina cribrosa (LC) in healthy subjects using enhanced depth imaging-optical coherence tomography (EDI-OCT).
  
  
  METHODS
  Serial horizontal and vertical B-scans of the optic nerve head (interval between images, approximately 30 μm) were prospectively obtained using EDI-OCT for both eyes of each healthy subject. After delineation of the anterior laminar surface, mean and maximum LC depths were measured in 11 equally spaced horizontal B-scans, and the depth of the anterior LC insertion was measured at 32 points along its circumference (reference plane, Bruch's membrane edges) for one randomly selected eye of each subject. Three-dimensional (3D) images of the anterior laminar surface and the peripapillary sclera were reconstructed from serial horizontal EDI-OCT B-scans to assess the 3D morphology of the anterior laminar surface.
  
  
  RESULTS
  Among the 61 eyes (61 subjects) enrolled, 31 were excluded because of poor LC image quality, and 30 were included for analysis (mean age, 40 ± 18 [range, 21-78] years). Both mean and maximum LC depth profiles showed an elevation in the central area and a depression in the superior and inferior midperiphery of the LC. The anterior LC insertion was more posteriorly located in the superior and inferior than in the nasal and temporal regions. Three-dimensional LC images showed a bowtie-shaped horizontal central ridge of the LC.
  
  
  CONCLUSIONS
  The LC has a central ridge ranging from the temporal to the nasal insertion areas and inserts more posteriorly in the superior and inferior than in the nasal and temporal regions. Further investigation is needed to elucidate the significance of these findings in the pathophysiology of glaucoma.
authors.affiliation: Einhorn Clinical Research Center, New York Eye and Ear Infirmary, New York, New York, USA. sungchulpark1225@gmail.com
authors.forename: Sung Chul
authors.initials: SC
authors.lastname: Park
authors.forename: Saman
authors.initials: S
authors.lastname: Kiumehr
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Teng
authors.forename: Celso
authors.initials: C
authors.lastname: Tello
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Liebmann
authors.forename: Robert
authors.initials: R
authors.lastname: Ritch
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000033:anatomy & histology*; D011446:Prospective Studies; D012590:Sclera / Q000033:anatomy & histology*; D041623:Tomography, Optical Coherence; D055815:Young Adult