Lamina Cribrosa Morphology in Glaucomatous Eyes with Hemifield Defect in a Korean Population.

PURPOSE

To compare regional variations in lamina cribrosa (LC) curvature and depth between healthy eyes (group 1) and naïve eyes with primary open-angle glaucoma (POAG) having superior (group 2), inferior (group 3), and both (group 4) hemifield retinal nerve fiber layer (RNFL) defects.

DESIGN

Cross-sectional study.

PARTICIPANTS

Each group consisted of 39 eyes of 39 Korean patients who were matched for age, sex, and axial length.

METHODS

The LC curvature index (LCCI) and LC depth (LCD) were measured in B-scan images obtained using enhanced depth imaging OCT at 7 locations spaced equidistantly across the vertical optic disc diameter. Superior and inferior LCCI and LCD were compared by calculating the superior-to-inferior (Sup/Inf) ratios.

MAIN OUTCOME MEASURES

Comparisons of LCCI, LCD, and Sup/Inf ratio among the 4 groups.

RESULTS

Compared with healthy eyes (group 1), LCCIs were larger at the superior and middle planes in group 2, at the inferior and middle planes in group 3, and at all planes in group 4 (P ≤ 0.003). The LCD showed similar results, but there was no difference in superior planes between groups 1 and 2. The Sup/Inf ratio of LCCI differed significantly between groups 1 (1.03) and 2 (1.20), groups 1 and 3 (0.79), groups 2 and 3, groups 2 and 4 (0.96), and groups 3 and 4 (all P < 0.001), but not between groups 1 and 4 (P = 0.273). The Sup/Inf ratio of LCD differed only between groups 2 and 3 (P = 0.002).

CONCLUSIONS

Eyes with POAG showed regional differences in LC morphology, corresponding with the location of RNFL defects. The regional variations in LCCI suggest that LC morphology in POAG would be better assessed on a regional basis than by a global index.