DTI parameters of axonal integrity and demyelination of the optic radiation correlate with glaucoma indices
In glaucoma, damage of retinal ganglion cells may continue to the linked optic radiations. This study investigates the correlation of glaucoma severity indicators with parameters of axonal and myelin integrity of the optic radiations.
In this observational case–control study, 13 patients with normal-tension glaucoma, 13 patients with primary open-angle glaucoma, and seven control subjects (mean age, 57.6 ± 12.5 years) were randomly selected for diffusion tensor imaging (DTI) of the optic radiations. The results of the frequency doubling test (FDT) and the HRT-based linear discriminant functions of Burk (BLDF) and Mikelberg (MLDF) were correlated with the mean of the fractional anisotropy (FA), apparent diffusion coefficient (ADC), and radial diffusivity (RD) of the optic radiations. Multiple correlation analysis, corrected for age, stage of cerebral microangiopathy, diagnosis group, and gender was conducted at increasing thresholds of linear anisotropy (CL) to reduce mismeasurements because of complex fiber situations.
The best correlations were found for BLDF with FA at CL threshold 0.3 (0.594, p = 0.001), with ADC at CL 0.4 (−0.511, p = 0.005), and with RD at CL 0.4 (−0.585, p = 0.001). MLDF correlated with FA at CL 0.4 (0.393, p = 0.035). The FDT score correlated with FA at CL 0 (−0.491, p = 0.007) and with RD at CL 0 (−0.375, p = 0.045).
In glaucoma, DTI-derived parameters of the axonal integrity (FA, ADC) and demyelination (RD) of the optic radiation are linked to HRT-based indices of glaucoma severity and to impairment of the spatial-temporal contrast sensitivity.
KeywordsDiffusion tensor imaging Glaucoma Optic nerve head Optic radiation
This study was supported by the Federal Ministry of Education and Research (BMBF), Bonn, Germany (excellence cluster Medical Valley EMN, Grant MVEMN-A-02), and the Johannes und Frieda Marohn-Stiftung at the University of Erlangen, Germany.
The funding organizations had no role in the design or conduct of this research, in the collection, management, analysis, and interpretation of the data, or in preparation, review, or approval of the manuscript. .
None of the authors has any financial/ conflicting interests to disclose. The authors had full control of all primary data and agree to allow Graefe’s Archive for Clinical and Experimental Ophthalmology to review their data if requested.
- 4.van Swieten JC, van den Hout JH, van Ketel BA, Hijdra A, Wokke JH, van Gijn J (1991) Periventricular lesions in the white matter on magnetic resonance imaging in the elderly: a morphometric correlation with arteriolosclerosis and dilated perivascular spaces. Brain 114:761–774PubMedCrossRefGoogle Scholar
- 10.Liao D, Cooper L, Cai J, Toole J, Bryan N, Burke G, Shahar E, Nieto J, Mosley T, Heiss G (1997) The prevalence and severity of white matter lesions, their relationship with age, ethnicity, gender, and cardiovascular disease risk factors: the ARIC Study. Neuroepidemiology 16:149–162PubMedGoogle Scholar
- 11.Breteler MM, van Swieten JC, Bots ML, Grobbee DE, Claus JJ, van den Hout JH, van Harskamp F, Tanghe HL, de Jong PT, van Gijn J, Hofman A (1994) Cerebral white matter lesions, vascular risk factors, and cognitive function in a population-based study: The Rotterdam Study. Neurology 44:1246–1252PubMedCrossRefGoogle Scholar
- 21.Burk RO, Noack H, Rohrschneider K, Volcker HE (1999) Prediction of glaucomatous visual field defects by reference plane independent three-dimensional optic nerve head parameters. In: Wall M, Wild JM (eds) Perimetry Update 1998/1999: Proceedings of the XIIIth International Perimetric Society Meeting, Gardone Riviera (BS), Italy, September 6–9, 1998, Kugler, The Hague, pp 463–474Google Scholar
- 24.El-Rafei A, Engelhorn T, Wärntges S, Dörfler A, Hornegger J, Michelson G (2011) A framework for voxel-based morphometric analysis of the optic radiation using diffusion tensor imaging in glaucoma. Magn Reson Imaging 29(8):1076–1087Google Scholar
- 26.Castedo J, Duque A, Roa E, Rodrigo P (2006) Atlas of white matter anatomy with fiber tractography by diffusion tensor MRI. 18th Annual Meeting of the Swiss Society of Neuroradiology SGNR/SSNR, Geneva Switzerland. http://www.neurorgs.com/inv/Publi/Pdf/Poster%20Castedo.pdf. Accessed 27 August 2009
- 27.UAMS (1997) The Anatomy Project. Nashville, TN: Parthenon Publishing Group, 1997. http://anatomy.uams.edu/AnatomyHTML/atlas_html/eye_38.html. Accessed 10 September 2009
- 31.Hodapp E, Parrish RK, Anderson DR (1993) Clinical decisions in glaucoma. Mosby, St. Louis, MOGoogle Scholar
- 33.Maddess T, Henry GH (1992) Performance of nonlinear visual units in ocular hypertension and glaucoma. Clin Vision Sci 7(5):371–383Google Scholar
- 40.Barrick TR, Charlton RA, Clark CA, Markus HS (2010) White matter structural decline in normal ageing; a prospective longitudinal study using tract based spatial statistics. Neuroimage 51(2):565–577Google Scholar