Aim: to determine the value of RNFL thickness at which visual field defect becomes
detectable.
Methods: Our study included 29 normal subject and 36 glaucomatous patient (one
eye per person) .Every person was examined by OCTOPUS perimetry with glau
coma 30-2
program, and peripapillary RNFL thickness was measured by HIEDELBERGSPECTRALIS
SD_OCT.
Results: comparison of results showed higher sensitivity of OCT compared to
Perimetry. Mean RNFL thickness at which visual field defect showed was 87 microns.
Superior RNFL thickness value which correlated with inferior visual field defect was 101
microns, whereas inferior RNFL thickness value which correlated with superior visual
field defect was 75 microns .and the difference in RNFL thickness between normal and
glaucomatous visual field was significant (p<0.001).
Conclusion: in open-angle glaucoma , it needs significant thinning in RNFL before
visual field defects becomes detectable.