Relationship between structural abnormalities and short-wavelength perimetric defects in eyes at risk of glaucoma

PURPOSE: To determine the relative prevalence of blue-yellow: perimetric de fects and structural abnormalities of the optic nerve and nerve fiber layer in eyes at risk of glaucoma. METHODS: Seventy-two eyes (of 72 patients) at risk of glaucoma, with normal white-on-white full threshold perimetry, were examined prospectively with blue-yellow full-threshold perimetry (Humphrey), Structural evaluations wer e conducted with qualitative assessment of stereoscopic color optic disk ph otographs and monochromatic nerve: fiber layer photographs performed indepe ndently by three masked examiners (a glaucoma specialist and two glaucoma f ellows), and statistical analysis of summary parameters was obtained with s canning confocal laser tomography (abnormal defined as values outside 95%:c onfidence limits established in normal control subjects), RESULTS:! Kappa values for interobserver agreement were 0,64,0,88, and 0.79 for optic disk evaluation and 0.59, 0.60,:and 0.61 for nerve fiber layer e valuation. Thirteen (18%) of 72 eyes had blue-yellow abnormalities, A rotal of 30 eyes (42%) were identified as having a structural abnormality; 29 (4 0%) had qualitatively determined optic disk abnormalities, 21 (29%) had qua litatively determined nerve fiber layer defects, and 26 (36%) had statistic ally significant structural abnormalities. Twelve of 13 eyes with blue-yell ow defects had a detectable structural abnormality; all 12 had abnormalitie s identified with disk photography, nine with nerve fiber layer photography , and 12 by scanning laser tomography. CONCLUSIONS: Clinically detectable structural abnormalities frequently coex ist with blue-yellow perimetric defects in patients with ocular hypertensio n. A substantial proportion of patients with ocular hypertension with norma l blue yellow perimetry has early detectable glaucomatous structural abnorm alities. (C) 2000 by Elsevier Science Inc. All rights reserved.