Abstract
Abstract: :
Purpose: To determine whether glaucoma patients with progressive visual field loss on conventional perimetry exhibit concomitant changes in optic disc morphology. Methods: A retrospective analysis identified 24 eyes of 20 patients with primary open angle glaucoma (POAG) who had serial visual field tests (Humphrey automated perimetry) and serial confocal scanning laser tomography (Heidelberg Retinal Tomograph [HRT]) over a minimum period of 24 months. Visual fields results were read by three glaucoma specialists, masked to the patients identity and HRT results, and categorized as either being stable (n = 16) or progressing (n = 8). HRT results for the eyes with either stable visual fields or progressive visual field loss were compared using both the standard HRT change analysis (topographic differences) and a quantitative regional analysis technique (Trick, et al, ARVO 2001) that compares surface height measurements at 128 distinct locations in the papilla and in the peripapillary retina. Results: : Six of 24 POAG eyes showed progression of damage on the HRT. Five of the 16 POAG eyes with stable visual fields exhibited evidence of glaucomatous change on HRT, while one of the eight eyes with progressing visual fields exhibited evidence of glaucomatous change on HRT. There was no significant difference in the "mean absolute difference" between the two groups (p = 0.296). Similarly, there was no significant difference in the "no change probability" between the two groups (p = 0.792). Quantitative regional analysis found no significant differences (average p = 0.67) at any of the 128 locations measured. Conclusion: In POAG patients the progression of functional deficits (visual field loss) and changes in optic disc morphology are not strongly associated. POAG patients may exhibit a detectable progression of visual field loss without a concomitant change in optic disc topography. These findings support the synergistic use of both visual field testing and optic disc tomography for detecting the progression of glaucomatous optic neuropathy.
Keywords: 498 optic disc • 599 topography • 624 visual fields