Heidelberg retina tomography and optical coherence tomography in normal, ocular-hypertensive, and glaucomatous eyes

Purpose: To evaluate optic disc and retinal nerve fiber layer (RNFL) appear ance in normal, ocular-hypertensive, and glaucomatous eyes undergoing confo cal scanning laser ophthalmoscopy and optical coherence tomography (OCT). Design: Prospective, cross-sectional study. Participants: Seventy-eight eyes of 78 consecutive normal (n = 17), ocular- hypertensive (n = 23), and glaucomatous subjects (n = 38) were enrolled. Methods: Each patient underwent complete ophthalmic examination, achromatic automated perimetry, confocal scanning laser ophthalmoscopy (Heidelberg Re tinal Tomography [HRT]), and OCT. Topographic HRT parameters (disc area, cu p-disc ratio, rim area, rim volume, cup shape measure, mean RNFL thickness, and cross-sectional area) and mean OCT-generated RNFL thickness were evalu ated in each group. Main Outcome Measures: OCT and HRT assessment of optic disc and RNFL anatom y. Results: OCT RNFL thickness showed no difference between normal and ocular- hypertensive eyes (P = 0.15) but was significantly less in glaucomatous eye s (P < 0.001). HRT measurements of rim area, cup-disc ratio, cup shape meas ure, RNFL thickness, and RNFL cross-sectional area were significantly less in glaucomatous eyes (all P < 0.005) and were correlated with mean OCT RNFL thickness (all P < 0.02). RNFL thickness using OCT or HRT was highly corre lated with visual field mean defect during achromatic perimetry (P < 0.0001 ). Conclusion: Both HRT and OCT can differentiate glaucomatous from nonglaucom atous eyes. RNFL thickness measurements using OCT correspond to disc topogr aphic parameters using HRT.