Czech and Slovak Ophthalmology 162 10.31348/2020/21 Original article Optic Chiasm Width in Normal-Tension and High-Tension Glaucoma Lešták Ján https://orcid.org/0000-0001-9630-3441 Kynčl Martin Fůs Martin https://orcid.org/0000-0003-3245-4544 Marešová Klára https://orcid.org/0000-0002-9973-3145 10 10 2020 3 4

Purpose: The aim of our study was to find out whether in patients with hypertensive glaucoma (HTG) and normotensive glaucoma (NTG), there is a change in the size of the chiasm depending on the changes in the visual field. Therefore, we retrospectively measured the width of the chiasm in the patients to whom we measured the size of the corpus geniculatum laterale in 2013. Materials and methods: The group consisted of two groups of patients. Nine with hypertensive glaucoma (HTG) and nine with normotensive glaucoma (NTG). The diagnosis was based on a complex ophthalmological examination and in NTG and electrophysiological examination. The visual field was examined by a rapid threshold program on the Medmont M700. The sum of the sensitivity from both visual fields in the range of 0-22 degrees was compared with the width of the chiasm obtained by the magnetic resonance imaging using the eight channel head coil. The measured values of all subjects were analyzed using a paired t-test and a correlation coefficient. Results: We found a reduction in the chiasma width in both glaucoma groups. We found a statistically significant difference in the size of the chiasm (p = 0.0003) between the control group and the HTG group (p = 0.001). The narrowing of the chiasm showed a slight correlation in HTG with changes in the field of vision (r = 0.139) and in NTG a moderate correlation (r = 0.375). Conclusion: We found a reduction in the size of the chiasm in both HTG and NTG. The sum of sensitivities in the central parts of the visual field, however, more correlated with the reduction in the size of the chiasm in NTG. This finding shows that there are two different diagnostic groups.

 Hypertensive glaucoma normotensive glaucoma optic chiasm width MRI changes in visual field References Kyncl M, Lestak J, Sverepa M, Ettler L, Rozsival P.: The anterior visual pathway in normal-tension glaucoma. Indian Journal of Research. 2015 Jan;4(1):10–14. Lestak J, Kyncl M, Svata Z, Rozsival P.: Lateral Geniculate Nucleus in Hypertensive and Normotensive Glaucoma. J Clin Exp Ophthalmol. 2013 Feb;4(2): DOI:10.4172/2155-9570.1000269.10.4172/2155-9570.1000269 Araie M, Yamagami J, Suziki Y.: Visual field defects in normaltension and high-tension glaucoma. Ophthalmology. 1993 Dec;100(12):1808–1814. Lestak J, Nutterova E, Bartosova L, Rozsival P.: The Visual Field in Normal tension and Hypertension Glaucoma. International Journal of Scientific Research. 2014 Dec;3(12):49–51. Lester M, De Feo F, Douglas GR.: Visual field loss morphology in high-and normal-tension glaucoma. J Ophthalmol. 2012 Feb; 327326. [Epub 2012: doi:10.1155/2012/327326].10.1155/2012/327326 Shin IH, Kang SY, Hong S, Kim SK, Seong GJ, Tak MK. et al.: Comparison of OCT and HRT findings among normal tension glaucoma, and high tension glaucoma. Korean J Ophthalmol. 2008 Dec;22(4): 236–241. Lestak J, Nutterova E, Pitrova S, Bartosova L.: High tension versus normal tension glaucoma. A comparison of structural and functional examinations. J Clin Exp Ophthalmol. 2012 Mar; S:5. [Epub doi. org/10.4172/2155-9570.S5-006].10.4172/2155-9570.S5-006 Prasad S, Galetta SL. Handbook of Clinical Neurology. 102. Amsterdam (The Netherlands): Elsevier; 2011. Anatomy and physiology of the afferent pupilary systém; 3–19. Shou T, Liu J, Wang W, Zhou Y, Zhao K.: Differential dendritic shrinkage of alpha and beta retinal ganglion cells in cats with chronic glaucoma. Invest Ophthalmol Vis Sci. 2003 Jul;44(7): 3005–3010. Erzos MG, Peckevik Y, Ayintap E, Gunes IB, Mart DK, Yucel E. et al.: MR Imaging of the Anterior Visual Pathway in Primary Open-Angle Glaucoma: Correlation with Octopus 101 Perimetry and Spectralis Optical Cherence Tomography Findings. Curr Eye Res. 2013 May;42(7): 995–1001. Hernowo AT, Boucard ChC, Jansonius NM, Hooyman JM, Cornelissen FW. et al: Automated Morphometry of the Visual Pathway in Primary Open-Angle Glaucoma. Invest Ophthal & Vis Sci. 2011 Apr;52(5): 2758–2766. Iwata F, Patronas NJ, Caruso RC, Podqor MJ, Remaley NA, Kupfer C. et al: Association of Visual Field, Cup-Disc Ratio, and Magnetic Resonance Imaging of Optic Chiasm. Arch Ophthalmol. 1997 Jun;115(6): 729–733. Murai H, Suzuki Y, Kiyosawa M, Tokumaru AM, Ashii K, Mochizuki M.: Positive correlation between the degree of visual field defect and optic radiation damage in glaucoma patients. Jpn J Ophthalmol. 2013 May;57(3):257–262. Omodaka K, Murata T, Sato S, Takahashi M, Nagasaka T, Doi H. et al.: Correlation of magnetic resonance imaging optic nerve parameters to optical coherence tomography and the visual field in glaucoma. Clin and Exp Ophthalmol. 2014 May- -Jun;42(4):360–368. Zhang YQ, Jing LiJ, Xu L, Wang ZC, Yang H, Chen CX. et al.: Anterior visual pathway assessment by magnetic resonance imaging in normal-pressure glaucoma. Acta Ophthalmol. 2012 Jun;90(4):e295–302. Kashiwagi K, Okubo T, Tsukahara S.: Association of magnetic resonance imaging of anterior optic pathway with glaucomatous visual field damage and optic disc cupping. J Glaucoma. 2014 Jun;13(3):189–195.