Early treatment diabetic retinopathy study (ETDRS) subfields.

<p>Macular ganglion cell (mGCL) and retinal nerve fiber (mRNFL) layers were measured in each of the nine macular areas defined by the ETDRS circle. Abbreviation: C0, central fovea; IS, inner superior; IN, inner nasal; II, inner inferior; IT, inner temporal; OS, outer superior; ON, outer nasal; OI, outer inferior; and OT, outer temporal; RE, right eye; LE, left eye.