Discrimination between normal and glaucomatous eyes with scanning laser polarimetry and optic disc topography: a preliminary report.

PURPOSE: To test the ability of structural parameters (as measured by scanning laser polarimetry (SLP) software 1.0.12 and confocal scanning laser ophthalmoscopy (CSLO) to discriminate between normal and glaucomatous eyes.

METHODS

A total of 112 patients with primary open-angle glaucoma and 88 normal individuals were enrolled in the study. All individuals underwent a thorough ophthalmic evaluation, a 24-2 full threshold Humphrey visual field, SLP with the GDx, and CSLO with the TOPSS. Patients with marked cataract or low vision were excluded from the study. Cut-off points were selected and receiver operator characteristic (ROC) curves were created for each individual CSLO and SLP parameter. Finally, multivariate dicriminant formulas were developed in order to achieve a better sensitivity (Se)/specificity (Sp) ratio for the diagnosis of glaucoma, initially separately for each device, and then combining parameters from CSLO and SLP.

RESULTS

The mean deviation for the glaucoma group was -10.63 +/- 7.58 dB. Multivariate discriminant formulas resulted in better sensitivity/specificity ratios than any individual parameter, either for CSLO (Se: 90%; Sp: 81%; accuracy: 86%) or SLP (Se: 87%; Sp: 86%; accuracy: 86%). The multivariate formula combining parameters from both devices resulted in an improvement in the ability to diagnose glaucoma. An area under the ROC curve of 0.97 was obtained, with a sensitivity of 93%, a specificity of 91%, and an accuracy of 92%.

CONCLUSIONS

The combination of structural parameters derived from CSLO and SLP in a multivariate discriminant formula may enhance the ability to diagnose glaucoma. Further studies investigating a random population are needed in order to test the validity of this formula.