Influence of angular width and peripapillary position of localized retinal nerve fiber layer defects on their detection by time-domain optical coherence tomography.

Purpose: To investigate the influence of angular width and peripapillary position of localized retinal nerve fiber layer (RNFL) defects on their detection by the time-domain optical coherence tomography (OCT).

Methods: Fast RNFL Stratus OCT scans were obtained from 186 eyes of 186 newly detected glaucoma patients with only a single, localized RNFL defect in either eye. The RNFL defects were divided into subgroups according to their angular width at 15° intervals and superior or inferior position. In the sector average graph of OCT results, abnormal clock-hour sectors were evaluated at P < 5%.

Results: Among 154 eyes included in the final data analysis, mean angular width of localized RNFL defects was 21.82 ± 10.38°, and 108 eyes (70.1%) had an inferiorly located RNFL defect. Localized RNFL defects with an angular width interval of 30° to 45° were more frequently detected by Stratus OCT than those with an angular width of <15° (odds ratio = 30.32, P = 0.001). Inferior RNFL defects were not detected more frequently by Stratus OCT than superior RNFL defects (odds ratio = 1.58, P = 0.24).

Conclusions: Only the angular width of localized RNFL defects had a significant influence on the sensitivity of the time-domain OCT.