Glaucoma without cupping.
BACKGROUND: Although glaucoma can exist with normal intraocular pressures (IOPs), clinicians still rely on the presence of a large cup to "flag" suspects, regardless of IOP, whereas a small cup at the same pressure level is often ignored. High-tech instruments offer a new dimension of evaluation in the objective assessment of structure when subjective tests of function and/or ophthalmoscopic observations are equivocal. CASE REPORTS: Thirteen cases are presented and show evidence of glaucoma based on glaucomatous visual-field defects, often with steadily rising intraocular pressures and retinal nerve fiber layer loss. Surprisingly, these patients maintained small C/D ratios. Accordingly, ophthalmoscopy and/or disk topography classified these disks as normal. CONCLUSIONS: Although unrecognized in virtually the entire world's ophthalmic literature, normal cup glaucoma is a real clinical entity. At least half the normal cup glaucoma cases presented herein have disk drusen (obvious, subtle, or occult), while others are highly myopic and/or have documented IOP spikes. Several of the cases defy classification and explanation at the present time.