title: Comparison of the thickness of the lamina cribrosa and vascular factors in early normal-tension glaucoma with low and high intraocular pressures.
abstract: OBJECTIVE
  To compare the thickness of the lamina cribrosa (LC) and vascular factors of early normal-tension glaucoma (NTG) patients with high and low intraocular pressure (IOP) that are expected to be associated with the development of glaucoma.
  
  
  METHODS
  Seventy-one Korean NTG patients with low IOP (the highest IOP <15 mmHg, 40 patients) and high IOP (the lowest IOP >15 mmHg, 31 patients) were included in this study. The thickness of LC and vascular factors were compared. The thickness of the LC was measured using the enhanced depth imaging method with spectral domain optical coherence tomography (Heidelberg Spectralis).
  
  
  RESULTS
  The mean thickness of the central LC was 190.0 ± 19.2 µm in the low IOP group and 197.8 ± 23.6 µm in the high IOP group, but there was no statistical significant difference between the two groups (p > 0.05). The prevalence of self-reported Raynaud phenomenon was significantly higher in the low IOP group (33.0%) than the high IOP group (10.3%, p = 0.04).
  
  
  CONCLUSIONS
  The laminar thickness did not significantly differ between the high and low IOP groups. However, the prevalence of Raynaud phenomenon was higher in the low IOP groups. These results suggest that the development of glaucoma with low IOP patients may be more influenced by peripheral vasospasm, such as Raynaud phenomenon, rather than laminar thickness in NTG.
authors.affiliation: Cheil Eye Hospital and Cheil Eye Research Institute, Daegu, Korea.
authors.forename: Jee Hyun
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Cheil Eye Hospital and Cheil Eye Research Institute, Daegu, Korea.
authors.forename: Tae Yoon
authors.initials: TY
authors.lastname: Lee
authors.affiliation: Cheil Eye Hospital and Cheil Eye Research Institute, Daegu, Korea.
authors.forename: Jong Wook
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Cheil Eye Hospital and Cheil Eye Research Institute, Daegu, Korea.
authors.forename: Kyoo Won
authors.initials: KW
authors.lastname: Lee
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007429:Intraocular Pressure; D057066:Low Tension Glaucoma / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D011928:Raynaud Disease / Q000175:diagnosis*; D012165:Retinal Ganglion Cells / Q000473:pathology; D041623:Tomography, Optical Coherence; D014065:Tonometry, Ocular; D014786:Vision Disorders / Q000175:diagnosis; D014794:Visual Fields
keywords: Enhanced depth imaging method; Lamina cribrosa; Low tension glaucoma; Spectral domain optical coherence tomography