Abstract
Purpose:
To investigate patterns of subsequent progression of localized retinal nerve fiber layer (RNFL) defect and to quantify extents of progression in normal-tension glaucoma (NTG) patients.
Methods:
Thirty-three eyes of consecutive 33 NTG patients who had shown continuous progression of localized RNFL defect on serial red-free fundus photographs were selected for the study. Patterns of subsequent progression of localized RNFL defect were categorized and extents of progression were quantified. Serial evaluations of disc stereophotographs and visual fields were also performed to detect progression.
Results:
The most common pattern was continuous widening of the defect towards the macula (n = 11; 33.3%) followed by sharpening of the defect border after widening of the defect towards the macula (n = 5; 15.2%), continuous widening of the defect away from the macula (n = 2; 6.1%), and deepening of the defect after appearance of new defect (n = 2; 6.1%). Four eyes (12.1%) simultaneously showed two patterns of subsequent progression. In 13 eyes that showed continuous widening of the defect, subsequent angular widening towards the macula and away from the macula were 9.2 ± 6.0° (range: 1.1-24.4°, n = 11) and 5.2 ± 4.9° (range: 0.3-11.3°, n = 2), respectively. Thirty-two eyes showed no progression of optic disc cupping. Out of the 23 eyes in which Humphrey central 30-2 threshold visual field were performed after progression of RNFL defect, 13 eyes showed no deterioration in the visual field.
Conclusions:
There were nine patterns of subsequent progression of localized RNFL defect. Among them, continuous RNFL loss proceeding temporally was the most common one. Initial progression of defect proceeded temporally might be at a risk of further RNFL loss temporally.
Keywords: 610 nerve fiber layer