Quantitative assessment of optic disc edema using spectral domain optical coherence tomography

Abstract

Introduction Optic disc edema (ODE) can be caused by a variety of conditions including pseudotumor cerebri, hypertension, diabetes, uveitis, anemia, lymphoma, and papillitis. Improvement in the quality of optical coherence tomography (OCT) can support the diagnosis and management of ODE. OCT may help in this diagnosis by showing peripapillary retinal nerve fiber layer (RNFL) thickening. Aim of the work To evaluate quantitative assessment of optic disc edema by measuring peripapillary nerve fiber layer (RNFL) thickness, and peripapillary maximum neurosensory retinal (MNSR) thickness in the four quadrants using spectral domain OCT. Patients and methods The study was done in El-Minya Investigation Eye Center between May 2012 and May 2013. The study included 21 eyes of 16 patients with optic disc edema and 20 eyes of 11 normal control persons. Both patients and normal control were examined by spectral domain OCT, two sets of measurements were evaluated and compared: Peripapillary RNFL thickness measurement in four quadrants using the standard optic disc cube 200 × 200 acquisition protocol, spectral domain OCT, Peripapillary maximum neurosensory retinal thickness (MNSR) in four quadrants using high definition 5 line images. Results In ODE group, 21 eyes of 16 patients were evaluated. The control group included 20 eyes of 11 normal subjects. The Mean average peripapillary RNFL was 93.1 ± 8.2 in control group 132.3 ± 46 µ in mild ODE, 139.4 ± 29.2 µ in moderate ODE and 264.2 ± 116.9 µ in severe ODE. The mean average peripapillary MNSR in the four quadrants was 350.1 ± 36.3 µm in control group, 458.7 ± 37.3 µm in mild ODE, 634.4 ± 35.01 µm in moderate ODE and 968.3 ± 245 µm in severe ODE. Conclusion There was a statistically significant increase in mean RNFL thickness and mean MNSR in four quadrants in all grades of ODE group compared with the control group ( P = 0.001). There was a strong positive correlation ( r = 0.89, P = 0.001) between the mean MNSR and the mean RNFL in eyes with ODE.