Abstract
Purpose: :
To evaluate the visual sensitivity and retinal nerve fiber layer thickness (RNFLT) in the normal visual hemifield of glaucomatous eyes with localized visual field loss compared with hemifield values of glaucoma suspect and normal eyes.
Methods: :
Normal volunteers, glaucoma suspect, and glaucoma patients underwent complete eye examination, standard automated perimetry (SAP), optic disc photography, scanning laser polarimetry (GDxECC, Carl Zeiss Meditec, Dublin, CA), time-domain OCT (Stratus OCT, Carl Zeiss Meditec, Dublin, CA) and spectral- domain OCT (RTVue, Optovue, Inc., Fremont, CA). Glaucoma suspects consisted of eyes with ocular hypertension (IOP > 24 mmHg) or glaucomatous optic neuropathy and normal SAP. Glaucomatous eyes had neuroretinal rim atrophy and corresponding SAP defect in one hemifield present on two reliable examinations. Normal hemifields (characterized by no points with a p<0.02 on the pattern standard deviation plot) were randomly selected in normal subjects and glaucoma suspects, and compared to normal hemifields of glaucomatous eyes. Mean retinal sensitivity values (dB) and mean RNFLT were calculated; a one-way analysis of variance with Tukey HSD adjustment for multiple comparisons was performed.
Results: :
Thirty-two age-matched normal volunteers (mean age 64.6±10.0 years), 21 glaucoma suspects (mean age 65.2±10.5 years), and 22 glaucoma patients (mean age 70.1±11.2 years, average visual field mean deviation -6.0±3.8) were enrolled. Mean retinal sensitivity values (dB) in the normal hemifield were similar (p>0.05) among normal, glaucoma suspect, and glaucomatous eyes (29.2±1.7, 29.8±1.8, and 28.2±1.8, respectively). Mean normal hemifield RNFLT in glaucomatous eyes using GDxECC and Stratus OCT was significantly thinner (p=0.01 and 0.006) in glaucomatous eyes (55.8 and 102.4 microns) compared with normal eyes (62.1 and 120.9 microns); no differences were observed using SDOCT (94.0 and 103.1, p =0.1). Mean normal hemifield RNFLT was similar (p>0.05) in glaucoma suspects compared with normal eyes using GDxECC, Stratus OCT and SDOCT (63.3, 116.0 and 98.0 microns, respectively).
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • nerve fiber layer • visual fields