Diagnostic Accuracy of Three-Dimensional Neuroretinal Rim Thickness for Differentiation of Myopic Glaucoma From Myopia.

PURPOSE

To compare the diagnostic accuracy of three-dimensional neuroretinal rim (3D-NRR) and peripapillary retinal nerve fiber layer (RNFL) thickness for differentiation of myopic glaucoma from myopia.

METHODS

Healthy myopic individuals (n = 193 eyes) and age-matched myopic glaucoma patients (n = 61 eyes) were enrolled. A 200 × 200-optic disc cube scan was performed with Cirrus HD-OCT. The rates of false-positive errors were compared between RNFL and 3D-NRR thickness measurements. The diagnostic accuracies of RNFL and 3D-NRR thickness for myopic glaucoma were compared by calculating the areas under receiver operating characteristic (AUROC) curves and the partial area under the curve (pAUC) for sensitivity ≥90%.

RESULTS

The overall false-positive rate was significantly greater for RNFL thickness (26.9%) than for 3D-NRR thickness (2.1%, P < 0.001). False-positive RNFL-thickness errors were prevalent in the nasal peripapillary region. The 3D-NRR thickness relative to RNFL revealed a greater AUROC from the 12 to 6 o'clock and 9 o'clock sectors. Again, comparing 3D-NRR with RNFL thickness, the pAUC for sensitivity ≥90% was greater in the nasal quadrant, 12, 3, 4, and 5 o'clock sectors. Also, the sensitivity and specificity, based on the internal normative database, were greater for 3D-NRR than for RNFL thickness.

CONCLUSIONS

3D-NRR thickness measurement reduced the false-positive rate for glaucoma diagnosis and demonstrated better accuracy for glaucoma detection in myopic eyes. Measurement of 3D-NRR can be complementary to RNFL thickness measurement for differentiation of myopic glaucoma from myopia.