AIM:To analyze the diagnostic value of optical coherence tomography(OCT)for early primary open angle glaucoma(POAG)by measuring the thickness of macular ganglion cell complex(mGCC), peripapillary retinal nerve fiber layer(pRNFL), macular retinal nerve fiber layer(mRNFL)and retinal ganglion cell layer+inner plexiform layer(GCIP)in the macular region.

METHODS:A case-control study design was used to collect 82 patients(82 eyes)with early POAG who admitted to our hospital from January 2019 to January 2020. There were 40 healthy volunteers(40 eyes)in the same period selected as the control group(20 eyes for left and right eyes, respectively). All subjects underwent tests of uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA)and equivalent spherical power. The upper, lower, nasal, temporal and average pRNFL thickness, the upper, lower and average mGCC, mRNFL and GCIP thickness in the macular region were analyzed. Spearman was used to analyze the correlation among the average thickness of eachindices, and ROC curve was used to analyze the value of mGCC, pRNFL, mRNF and GCIP thickness parameters in diagnosing early POAG.

RESULTS:In the early POAG group, the thickness of upper, nasal, lower, temporal, average pRNFL and the thickness of upper, lower and average mGCC, mRNFL and GCIP were lower than those in the control group(all P<0.05). Average thickness of pRNFL was positively correlated with average thickness of mGCC, average mRNFL and average GCIP(r_s=0.582, 0.632, 0.456, all P<0.05); average thickness of mGCC was positively correlated with average thickness of mRNFL and average GCIP(r_s=0.583, 0.851, all P<0.05); Average thickness of mRNFL was positively correlated with average thickness of GCIP(r_s=0.528, all P<0.01). ROC curve analysis shows that the AUC value of mGCC thickness and average value in early diagnosis of POAG were all above 0.8, and the diagnostic efficiency was the highest.

CONCLUSION: OCT measurement of mGCC has certain value in diagnosing early POAG.