title: Optic nerve diffusion tensor imaging parameters and their correlation with optic disc topography and disease severity in adult glaucoma patients and controls.
abstract: OBJECTIVE
  To evaluate optic nerve diffusion tensor imaging (DTI) parameters in glaucoma patients and controls, and to correlate DTI parameters with the rim area obtained with Heidelberg retina tomography (HRT) and with the severity of glaucomatous damage using the Glaucoma Staging System.
  
  
  METHODS
  Pilot study.
  
  
  METHODS
  Twenty-seven patients with glaucoma and 12 control subjects underwent DTI and HRT imaging. Main outcome measures included: fractional anisotropy, mean diffusivity, axial diffusivity, radial diffusivity, HRT rim area, and Glaucoma Staging System stage.
  
  
  RESULTS
  In group comparison, mean diffusivity (1.33 vs. 0.91 μm/ms, P=0.0002), axial diffusivity (1.70 vs. 1.43 μm/ms, P=0.036), and radial diffusivity (1.24 vs. 0.71 μm/ms, P<0.0001) were significantly higher and fractional anisotropy (0.21 vs. 0.44, P<0.0001) was significantly lower in the glaucoma compared with those of control subjects. In glaucoma patients, mean, axial, and radial diffusivities increased and fractional anisotropy decreased as rim area decreases and the Glaucoma stage increased (P<0.05). However, there were no statistically significant differences in the DTI parameters when adjacent pairs of stages were compared (P>0.05).
  
  
  CONCLUSIONS
  DTI may be a useful technique for detection and evaluation of glaucomatous damage in the optic nerve, particularly for patients in whom conventional imaging and perimetry are not possible. Future studies are needed to evaluate how DTI parameters change longitudinally with glaucomatous damage within the visual pathways and address cerebrospinal fluid partial volume effects in diffusion tensor quantification, especially for patients with advanced glaucoma stage.
authors: Departments of *Ophthalmology and Visual Sciences †Neurology §Biostatistics ¶Radiology, Washington University School of Medicine, St Louis, MO ‡Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN ∥Department of Ophthalmology, University of California, San Francisco, CA.
authors: Sidney T
authors: ST
authors: Chang
authors: Junqian
authors: J
authors: Xu
authors: Kathryn
authors: K
authors: Trinkaus
authors: Melike
authors: M
authors: Pekmezci
authors: Stella N
authors: SN
authors: Arthur
authors: Sheng-Kwei
authors: SK
authors: Song
authors: Edward M
authors: EM
authors: Barnett
mesh_terms: D016022:Case-Control Studies; D056324:Diffusion Tensor Imaging; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009898:Optic Disk / Q000473:pathology*; D009900:Optic Nerve / Q000473:pathology*; D011446:Prospective Studies; D014054:Tomography / Q000295:instrumentation / Q000379:methods; D041623:Tomography, Optical Coherence / Q000295:instrumentation / Q000379:methods
references: Neurology. 2010 May 25;74(21):1702-10
references: 20498438
references: Neuroimage. 2009 Apr 15;45(3):679-86
references: 19162205
references: Arch Neurol. 2012 Jan;69(1):65-71
references: 21911658
references: Arch Ophthalmol. 1981 Apr;99(4):635-49
references: 6164357
references: J Magn Reson B. 1996 Jun;111(3):209-19
references: 8661285
references: Neuroradiology. 2004 May;46(5):339-50
references: 15103435
references: AJNR Am J Neuroradiol. 2005 Apr;26(4):951-6
references: 15814951
references: NMR Biomed. 2008 Jul;21(6):589-97
references: 18041806
references: Invest Ophthalmol Vis Sci. 2006 Aug;47(8):3374-80
references: 16877405
references: Arch Ophthalmol. 2000 Mar;118(3):378-84
references: 10721961
references: Br J Ophthalmol. 2006 Jun;90(6):674-8
references: 16464969
references: Magn Reson Q. 1991 Jan;7(1):1-30
references: 2043461
references: Magn Reson Med. 2002 Jan;47(1):24-31
references: 11754439
references: Brain. 2004 Nov;127(Pt 11):2498-505
references: 15342363
references: Curr Opin Ophthalmol. 2007 Mar;18(2):110-4
references: 17301611
references: Neuroimage. 2003 Nov;20(3):1714-22
references: 14642481
references: Neuroimage. 2006 Sep;32(3):1195-204
references: 16797189
references: NMR Biomed. 2008 Nov;21(9):928-40
references: 18756587
references: AJNR Am J Neuroradiol. 2011 Oct;32(9):1662-8
references: 21799043
references: Neuroimage. 2005 May 15;26(1):132-40
references: 15862213
references: Radiology. 2009 Aug;252(2):496-501
references: 19435941
references: Surv Ophthalmol. 2007 Nov;52 Suppl 2:S122-6
references: 17998036
references: Neuroimage. 2007 Oct 1;37(4):1138-47
references: 17689104
references: Neuroimage. 2008 Mar 1;40(1):1-10
references: 18187343
references: Neurology. 2009 Feb 17;72(7):589-94
references: 19073948
references: Ophthalmology. 1979 Oct;86(10):1803-30
references: 553256
references: Lancet. 2004 May 22;363(9422):1711-20
references: 15158634
references: Annu Int Conf IEEE Eng Med Biol Soc. 2007;2007:4312-5
references: 18002956
references: J Magn Reson Imaging. 2009 Feb;29(2):454-60
references: 19161202
references: Neuroimage. 2006 Apr 1;30(2):498-505
references: 16242968
references: Clin Exp Ophthalmol. 2009 Dec;37(9):836-41; quiz 903-4
references: 20092591
references: AJNR Am J Neuroradiol. 2012 Jan;33(1):128-34
references: 22116110
references: Am J Ophthalmol. 2006 Jan;141(1):24-30
references: 16386972
references: Neuroimage. 2002 Nov;17(3):1429-36
references: 12414282
references: NMR Biomed. 2002 Nov-Dec;15(7-8):435-55
references: 12489094