| 목적 : To investigate the relationship between optic disc torsion and macular ganglion cell inner plexiform layer complex (GCIPL) thickness measured by the Cirrus optical coherence tomography (Carl Zeiss Meditec, Dublin, CA) and to evaluate the differences of the GCIPL thickness parameters and their patterns comparing with retinal nerve fiber layer(RNFL) thickness for normal tension glaucoma(NTG) patients with optic disc torsion.방법 : Participants were divided by optic disc photography and standard automated perimetry into groups according to the presence of optic disc torsion and glaucoma. optic disc torsion group were divided further into supero-nasal torsion and inferio-temporal torsion groups according to direction of optic disc torsion. All of them were underwent OCT imaging with optic nerve head mode and GCIPL mode within a single day. The relationship between GCIPL thickness, ocular factors and the direction of optic disc torsion by regression analysis. Results were compared with those obtained for RNFL thickness.결과 : One hundred fifty seven control subjects and 155 patients with NTG patients were included in the present study. Among NTG eyes, 60.0% were eyes with optic disc torsion. Temporal RNFL thickness significantly different according to direction of disc torsion, supero-nasal torsion group shows significantly thinner temporal quadrant RNFL thickness despite of similar mean deviation score of visual field defects. While GCIPL thickness at all quadrants had no difference according torsion degree. Infero-temporal optic disc torsion with NTG group had shown significant less supero-temporal GCIPL loss.결론 : The direction of optic disc torsion influences temporal RNFL thickness while GCIPL thickness at all segments would not be affected. Infero-temporally optic disc torsion results less superior GCIPL loss which presents as less frequently correlated inferior visual field defects. It is hypothesized that more supero-nasally tortuous nerve fiber bundle would be more vulnerable to glaucomatous damage. supero-nasal optic disc torsion would place stress on the superior nerve axons, resulting in more vulnerable to damage to the axons of retinal ganglion cells in the superior region. |