title: Spectral domain optical coherence tomography cross-sectional image of optic nerve head during intraocular pressure elevation.
abstract: OBJECTIVE
  To analyze changes of the optic nerve head (ONH) and peripapillary region during intraocular pressure (IOP) elevation in patients using spectral domain optical coherence tomography (SD-OCT).
  
  
  METHODS
  Both an optic disc 200×200 cube scan and a high-definition 5-line raster scan were obtained from open angle glaucoma patients presented with monocular elevation of IOP (≥30 mm Hg) using SD-OCT. Additional baseline characteristics included age, gender, diagnosis, best-corrected visual acuity, refractive error, findings of slit lamp biomicroscopy, findings of dilated stereoscopic examination of the ONH and fundus, IOP, pachymetry findings, and the results of visual field.
  
  
  RESULTS
  The 24 patients were selected and divided into two groups: group 1 patients had no history of IOP elevation or glaucoma (n=14), and group 2 patients did have history of IOP elevation or glaucoma (n=10). In each patient, the study eye with elevated IOP was classified into group H (high), and the fellow eye was classified into group L (low). The mean deviation (MD) differed significantly between groups H and L when all eyes were considered (P=0.047) and in group 2 (P=0.042), not in group 1 (P=0.893). Retinal nerve fiber layer (RNFL) average thickness (P=0.050), rim area (P=0.015), vertical cup/disc ratio (P=0.011), cup volume (P=0.028), inferior quadrant RNFL thickness (P=0.017), and clock-hour (1, 5, and 6) RNFL thicknesses (P=0.050, 0.012, and 0.018, respectively), cup depth (P=0.008), central prelaminar layer thickness (P=0.023), mid-inferior prelaminar layer thickness (P=0.023), and nasal retinal slope (P=0.034) were significantly different between the eyes with groups H and L.
  
  
  CONCLUSIONS
  RNFL average thickness, rim area, vertical cup/disc ratio, cup volume, inferior quadrant RNFL thickness, and clock-hour (1, 5, and 6) RNFL thicknesses significantly changed during acute IOP elevation.
authors.affiliation: Department of Ophthalmology, Yeouido St. Mary's Hospital, College of Medicine, the Catholic University of Korea, 62, Yeuido-dong, Youngdeungpo-gu, Seoul 150-713, Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Ophthalmology, Yeouido St. Mary's Hospital, College of Medicine, the Catholic University of Korea, 62, Yeuido-dong, Youngdeungpo-gu, Seoul 150-713, Korea.
authors.forename: You Kyung
authors.initials: YK
authors.lastname: Lee
authors.affiliation: Department of Ophthalmology, Yeouido St. Mary's Hospital, College of Medicine, the Catholic University of Korea, 62, Yeuido-dong, Youngdeungpo-gu, Seoul 150-713, Korea.
authors.forename: Jung Il
authors.initials: JI
authors.lastname: Moon
authors.affiliation: Department of Ophthalmology, Yeouido St. Mary's Hospital, College of Medicine, the Catholic University of Korea, 62, Yeuido-dong, Youngdeungpo-gu, Seoul 150-713, Korea.
authors.forename: Myoung Hee
authors.initials: MH
authors.lastname: Park
keywords: elevated intraocular pressure; open angle glaucoma; optic nerve head; retinal nerve fiver layer; spectral domain optical coherence tomography