Systematic review of macular ganglion cell complex analysis using spectral domain optical coherence tomography for glaucoma assessment

Table 1 Properties of the various spectral domain optical coherence tomography instruments

	Cirrus HD-OCT (Carl Zeiss Meditec, Inc., Dublin CA, United States)	RTVue (Optovue, Inc., Fremont, CA, United States)	Spectralis (Heidelberg Engineering, Heidelberg, Germany)	3D OCT 2000 (Topcon Corporation, Tokyo, Japan)
Macular layer measured	GCIP	GCC	The entire retina (from =BM to ILM)	Macular RNFL GCIP (GCL+) GCC (GCL++)
Maps provided	Thickness map, deviation map and sectors	Thickness map, deviation map and significance map	Thickness map, asymmetry map, hemisphere asymmetry map and mean thickness map	Thickness map, significance map, average thickness asymmetry map
Grid dimensions (mm)	6 × 6	7 × 7	8 × 8	6 × 6

OCT: Optical coherence tomography; GCIP: Combined retinal ganglion cell (RGC) and inner plexiform layer (IPL); RNFL: Retinal nerve fiber layer; GCC: Ganglion cell complex = macular RNFL + GCIP; BM: Bruchs membrane; ILM: Internal limiting membrane.