Spectral-domain optical coherence tomography measurement of macular volume for diagnosing glaucoma

To determine the glaucoma diagnostic power of measuring the volume of the ganglion cell complex (GCC; 3 innermost retinal layers) using spectral-domain optical coherence tomography (SD-OCT).

Fifty eyes with open-angle glaucoma and 35 normal partipants were included for this study. SD-OCT (RTVue-100), and time-domain (TD)-OCT were used to measure total retinal, GCC (SD-OCT only), and circumpapillary retinal nerve fiber layer (cpRNFL) thicknesses in 50 eyes with open-angle glaucoma and in 35 without glaucoma.

Total retinal and GCC volumes in a macular area correlated with visual field mean deviation (GCC: r=0.580, P<0.001; total: r=0.458, P<0.001). The area under the receiver operating characteristic curve (AROC) was greater for macular GCC volume (0.922) than for macular total retinal volume, as measured by SD-OCT (0.857; P=0.020) or TD-OCT (0.841; P=0.025). GCC AROCs were smaller than cpRNFL AROCs determined using SD-OCT (0.971; P=0.110) or TD-OCT (0.970; P=0.122), but not in a statistically significant manner. AROC for the GCC was greatest in the inferior macula. Interclass correlation coefficient values were comparable for GCC and total retinal volumes.

Selective measurement of the GCC layer by SD-OCT improves diagnostic performance of the macular structural analysis for glaucoma diagnosis.