Macular morphology in patients with optic nerve head drusen and optic disc edema.

Purpose

In this study we investigated macular morphology, including individual retinal layers, in patients with optic nerve head drusen (ONHD) and optic disc edema (ODE) compared with healthy participants, using high-resolution spectral domain optical coherence tomography (OCT).

Design

Prospective, cross-sectional, observational study.

Participants

A total of 67 patients with ONHD, 36 patients with ODE, and 57 healthy participants.

Methods

High-resolution spectral domain OCT (Copernicus [OPTOPOL Technology S.A., Zawiercie, Poland] 3-μm resolution, 7 × 7 × 2-mm volumetric scans) was used to image macula morphology. Average retinal nerve fiber layer (RNFL) thickness was measured using a semiautomated method with manual correction of the internal limiting membrane, RNFL, and retinal pigment epithelium (RPE). Retinal and RNFL thicknesses were measured and analyzed in 3 circular zones (Early Treatment Diabetic Retinopathy Study protocol). Individual retinal layers at the macula were quantified by analyzing tomograms using ImageJ (http://rsbweb.nih.gov/ij/; Accessed June 1, 2013).

Main outcome measures

Average retinal and individual retinal layer thickness in patients with ODE or ONHD, and healthy controls.

Results

Patients with ONHD had thicker retinae in the inner annulus compared with patients with ODE and controls (significant in the temporal segment compared with those with ODE [P = 0.013] and in the superior segment compared with controls [P = 0.05]). Patients with ONHD had a significantly thinner inner plexiform layer (IPL) (P = 0.02), nerve fiber layer (P = 0.05), and RPE (P = 0.0001), and thicker ganglion cell layer (P = 0.003) and outer plexiform layer (OPL) (P < 0.001) compared with controls. Patients with ODE demonstrated the thickest retina and RNFL in the outer annulus (significant in the inferior segment compared with controls, P = 0.02 for both) with significant thickening in the IPL (P = 0.004), OPL (P < 0.003), and outer segment layer (P ≤ 0.02), and severe ganglion cell loss (P = 0.004) and RPE (P = 0.0001) thinning compared with healthy volunteers.

Conclusions

Our study shows that optic nerve diseases are associated with selective changes in different retinal layers in patients with ODE and ONHD. These findings may be of diagnostic value and could be taken into consideration in assessing patients and studying the pathogenesis of these conditions.