Identifying early glaucomatous changes - Comparison between expert clinical assessment of optic disc photographs and confocal scanning ophthalmoscopy

Objective: To compare the ability of expert clinicians, using qualitative a ssessment of stereoscopic optic disc photographs, and confocal scanning las er ophthalmoscope imaging to discriminate between healthy persons and patie nts with early glaucoma. Design: Comparative instrument validation study. Participants: Seventy-two healthy persons and 51 patients with early glauco ma (average visual field mean deviation, -3.6 dB). Early glaucoma was defin ed as a history of ocular hypertension and a reproducible visual field defe ct scoring 5 or less in the Advanced Glaucoma Intervention Study classifica tion, regardless of optic disc appearance. Intervention: Stereoscopic optic nerve head (ONH) photography and Heidelber g Retina Tomograph (HRT) imaging, (Heidelberg Engineering GmbH, Dossenheim, Germany). Main Outcome Measurer Ability of clinical assessment of stereoscopic ONH ph otographs and analysis of HRT parameters, taking into account the optic dis c size, to detect early glaucomatous optic disc changes. Results: The speci ficity of the majority opinion of five observers to detect early glaucomato us optic disc changes was 94.4%, with a sensitivity of 70.6%. Using the HRT analysis, the specificity was 95.8% and the sensitivity was 84.3%. Conclusions: Heidelberg Retina Tomograph image analysis that takes into acc ount the optic disc size is more sensitive than clinical assessment of ster eoscopic optic disc photographs in distinguishing between healthy persons a nd patients with early glaucoma. (C) 2000 by the American Academy of Ophtha lmology.