Abstract:  Objective  To measure macular parameters in patients with acute primary angle closure glaucoma (APACG) and investigate the differences in these parameters between the acute phase and the long-term period after intraocular pressure (IOP) control by using of optical coherence tomography (OCT). Design Retrospective case series. Participants Thirty patients with APACG acute attack in Handan Eye Hospital from December 2016 to December 2017 were enrolled. The affected eyes were used as the study group (33 eyes), and the contralateral eyes were used as the control group (27 eyes). Methods IOP, OCT, visual acuity, and slit lamp examination were performed at acute attack stage and 6 months after IOP control. The differences of retinal thickness parameters in macular OCT images at acute attack eyes from after IOP control were compared, and compared with the contralateral eyes. The image features of the OCT topographic map in the macular region were observed and analyzed. The macular central foveal thickness, retinal thickness, retinal volume, and average thickness of the scanned area were calculated using system software. Main Outcome Measures IOP and retinal thickness parameters. Results The mean intraocular pressure was (52.6±8.2) mmHg at the acute attack, and (14.2±4.1) mmHg at 6 months after treatment. Compared with the control of IOP, the thickness of the outer quadrant of the macular area, the inferior inner ring and the temporal retina at the acute attack were thicker (all P<0.05); the retinal volumes were increased (all P<0.05) and the average thickness of the scanning area was thickened (P=0.009). There was no significant difference in the macular thickness of the contralateral eye between the acute attack period and 6 months after IOP control (P=0.750). The mean retinal thickness of the attack eyes was thicker than that of the contralateral eyes during the acute attack period (P=0.001), and the mean retinal thickness of the attack eyes was thinner than that of the contralateral eyes at 6 months after IOP control (P=0.001). Conclusion Compared with that after IOP control, the macular retinal thickness becomes thicker in the acute stage of APACG, and the macular retinal thickness becomes thinner after 6 months of APACG. It is suggested that the macular retinal ganglion cells atrophy and thinning due to acute ocular hypertension injury. It is suggested to reduce the intraocular pressure as soon as possible to reduce the damage to the macular retina. (Ophthalmol CHN, 2024, 33: 23-27)