Evaluation of clinical and HRT II quantitative parameters to detect suspect and early glaucoma patients

Abstract

Abstract Purpose: To compare the different clinical and HRT II quantitative parameters among patients divided in three groups: control, suspect glaucoma and early glaucoma. Methods: The relative importance of each of a set of independent variables was assessed by stepwise discriminate analysis to identify and combine the most useful parameters of both clinical and HRT II methods. Afterwards the most significative original variables were combined to generate a new variable in such a way that the measurable differences between the groups are maximized by means of using a linear discriminate function (LDF) to generate a receiver operating characteristic (ROC) curve for each set of clinical or HRT II parameters. The differences between the ROC curves derived from LDF analysis by each method (clinical or HRT II) were tested for significance. Results: Two functions were found: Clinical = 9.69 ‐ 0.09*IOP + 0.05*Age ‐0.02*Pachymetry and HRT II = 5.83 + 0.71*FSM Mikelberg Function ‐ 7.43*RNFL cross‐sectional area + 32.44*mean RNFL thickness ‐ 10.25*rim/disc area. ROC curves were plotted and the areas for clinical and HRT II functions were 0.762 ± 0.042 and 0.757 ± 0.042 respectively. Conclusions: Despite of good discriminate results for single parameters to detect suspect or early glaucoma patients, a linear combined parameters appeared more effective statistically than clinical and HRT II single ones.