Abstract
Abstract: :
Purpose: To evaluate the status of retinal nerve fiber layer (RNFL) corresponding to intact hemifield in the eyes with normal–tension glaucoma (NTG) confined to one hemifield visual defect using scanning laser polarimetry Methods: In this prospective case–controlled study, 55 consecutive NTG eyes with hemifield defect based on Humphrey field analyzer (HFA, Zeiss–Humphrey, Dublin, CA, USA) 24–2 glaucoma hemifield test underwent scanning laser polarimetry (GDx–VCC system, Laser Diagnostic Technologies, San Diego, California, USA). 40 normal eyes from 40 subjects served as a control group. We compared GDx–VCC deviation–map algorithm scores and parametric values in the RNFL corresponding to the intact hemifield based on HFA between the study and control group. We also compared the RNFL thickness and deviation–map algorithm score between the two hemiretinas corresponding to intact hemifield and defective hemifield in the study group. Results: 12.5% (7/55 eyes) of NTG eyes showed an abnormal superior or inferior average probability in the quadrant corresponding to intact hemifield while none showed abnormal probability (P<5%) in the control group based on GDx–VCC. GDx–VCC in the deviation–map algorithm score showed significant difference between NTG eyes and control group in the quadrant corresponding to intact hemifield (P<0.05). The mean RNFL thickness in the affected quadrant corresponding to defective hemifield was significantly thinner than that in the quadrant corresponding to intact hemifield (P<0.05). Conclusions: In NTG eyes with visual field defect confined to one hemifield, some eyes also exhibited RNFL damage in the quadrants corresponding to intact hemifield based on scanning laser polarimetry (GDx–VCC).
Keywords: clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled • nerve fiber layer • imaging/image analysis: clinical