Abstract
Abstract: :
Purpose:To compare effects of myopic disc changes on retinal nerve fiber layer thickness (RNFL) in normal eyes and in eyes with early open angle glaucoma (OAG) . Methods:Enrolled were 105 control eyes and 77 eyes with early OAG. Myopic disc changes were observed in 34 eyes in the former and in 35 in the latter. The RNFL thickness was measured using Optical Coherence Tomography (OCT), and then subdivided into 12 segments. The RNFL thickness of each segment (S-RNFL-T) were calculated. The receiver operating characteristic curves (ROC) were plotted for each S-RNFL-T of glaucomatous eyes with and without myopic disc changes, on which sensitivity and false positive rate were determined by the mean deviation in the Humphrey Field Analyzer. Percent reduction of each S-RNFL-T in the OAG eyes relative to the control eyes was also calculated. A segment with the highest percent reduction in each individual was determined and the distribution of such a segment was compared between the OAG eyes with myopic disc changes and those without myopic disc changes. Results:In normal eyes, the average of each S-RNFL-T was not different between in those with and without myopic disc changes. The largest area under ROC in the OAG eyes with myopic disc changes was exhibited for inferior temporally segment thickness (93.3), while for inferior segment thickness without myopic changes (92.7). As for the distribution of segments with the highest percent reduction, the inferior temporally segment was the most frequent in the OAG eyes with myopic disc changes (48%), whereas there was no predilection in the distribution in those without myopic disc changes. Conclusion:Myopic disc changes were correlated with the reduction in the retinal nerve fiber thickness at the inferior area in early glaucomatous eyes.
Keywords: 484 nerve fiber layer • 432 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 481 myopia