Abstract
Abstract: :
Purpose: To assess longitudinally optic disc morphometry (Heidelberg Retina Tomograph, HRT) and pattern electroretinogram (PERG) in glaucoma suspect (GS) eyes under ocular hypotensive therapy. Methods: Twenty–eight patients with ocular hypertension, family history for glaucoma, normal achromatic automated perimetry (Humphrey 30–2) and normal optic disc were serially evaluated by perimetry, HRT and steady state PERG (1.7 c/deg sinusoidal gratings modulated at 7.5 Hz). Test–retest variability of HRT and PERG parameters was analyzed at baseline at two different visits within 4–6 months. During the follow–up (36 ± 4 months), patients underwent hypotensive treatment by beta–blockers (Maleate Timolol or Betaxolol) with or without prostaglandin analogues (Latanoprost). The following parameters were considered: HRT, rim area, cup/disc area ratio, rim volume and cup shape measure; PERG, 2nd harmonic response amplitude. Results: All patients showed a stable therapeutic IOP reduction (mean IOP during the follow–up: 14 ± 2 mmHg). When compared to baseline values, mean PERG amplitude increased (15 ± 2%; t–test for repeated measurements, p = 0.01) at the end of the study. Mean HRT parameters did not show significant changes. In individual patients, PERG amplitude increased (>2SD of test–retest variability) from baseline in 4/28 (14.3%), did not change in 23/28 (82%) and decreased in 1/28 (3.5%). HRT parameters and visual fields did not change significantly in any of the patients. Conclusions: Results indicate improvement of inner retinal function following therapeutic IOP reduction in GS and support, in agreement with other clinical studies,1 a neuroprotective role of ocular hypotensive treatment on the progression of early glaucomatous losses. 1. Kass MA, et al. Arch Ophthalmol. 2002;120:701–713.
Keywords: neuroprotection • electroretinography: clinical • ganglion cells