Macular Imaging in Highly Myopic Eyes With and Without Glaucoma

PurposeTo determine how evaluations of macular structures on spectral-domain optical coherence tomography compare with those of the optic disc and circumpapillary retinal nerve fiber layer (RNFL) in discriminating between highly myopic eyes with and without glaucoma.DesignRetrospective, comparative study.MethodsThe appearances of ganglion cell layer and RNFL on Spectralis macular scans (Heidelberg Engineering) and optic disc on photographs were evaluated by 2 observers. The receiver operating characteristic regression was conducted for macular ganglion cell complex and circumpapillary RNFL measurements on RTVue-100 (Optovue).ResultsNinety highly myopic eyes (−6.0 to −15.0 diopters; mean deviation [MD], −5.6 ± 5.1 dB) and 91 non-highly myopic eyes (1.0 to −5.5 diopters; MD, −4.9 ± 5.7 dB) were enrolled. In highly myopic eyes (<−6 diopters), the Cohen κ for qualitative decisions by observers was 0.363 for photographs and 0.946 for Spectralis macular scans, and observers' evaluations of Spectralis macular scans were more accurate (94.5% and 94.5%, respectively; P < .0001) than their evaluations of photographs (71.4% and 80.2%, respectively). In the receiver operating characteristic regression analyses assessing the influences of age, sex, MD, and axial length, the better MD (P = .002 to .016) and longer axial length (P = .031 to .041) were associated significantly with diagnostic performances for all or some spectral-domain optical coherence tomography parameters. The receiver operating characteristic curves of average macular ganglion cell complex and circumpapillary RNFL thicknesses were comparable at low MD.ConclusionsIn high myopes, observers' assessments of the spectral-domain optical coherence tomography macular scans may agree better and be more accurate than observers' optic disc assessments. Glaucoma diagnostic performance of the macular ganglion cell complex may be less affected by axial length compared with that of circumpapillary RNFL.