Abstract
Abstract: :
Purpose: To document the existence of normal cup glaucoma, estimate its prevalence and to categorize the causes when identifiable. Methods: A retrospective analysis of 600 glaucoma cases. Patients had high IOPs (between 26mm Hg–52mm Hg before treatment), abnormal reproducible threshold visual fields and corresponding objective nerve fiber layer abnormalities with either the GDx (previously LDT now Zeiss) or OCT (Zeiss) or both. However, all had normal cupping and neuroretinal rim as assessed ophthalmoscopically, by stereo disc photos, and by HRT II (Heidelberg) Moorfields regression analysis. Results: Based upon the above criteria, 29 (4.8%) of the cases had glaucoma without glaucomatous cupping. Of the 29, 12 (41%)had disc drusen (often subtle and initially not observed), 5 (17%)had myopia over 9 D, another 5 (17%) had IOP spikes associated with angle closure, pigmentary glaucoma, or Posner–Schlossman syndrome, one had a congenital epipapillary membrane, and the remaining 6 (20%)could not be classified at present. Conclusions: The prevalence of normal cup glaucoma in this study was 4.8%. Although still unrecognized in virtually the entire world’s ophthalmologic literature, normal cup glaucoma does exist. Reliance on ophthalmoscopy and/or disc topography alone often misses these cases. Normal cup glaucoma should join normal tension glaucoma as a diagnostic dilemma.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • clinical (human) or epidemiologic studies: prevalence/incidence • optic disc