AIM: To quantitatively analyze the changes of the peripapillary capillary vessel density(ppVD)and the peripapillary retina nerve fiber layer(pRNFL)thickness in patients with monocular retinal vein occlusion(RVO)by optical coherence tomography angiography(OCTA), and further analyze the correlation between the ppVD and the pRNFL thickness.

METHODS: Prospective observational research. A total of 43 patients diagnosed with monocular RVO were enrolled in the Department of Ophthalmology of the First Affiliated Hospital of Anhui University of Science and Technology from January to December 2021, among which 43 RVO eyes were regarded as the affected group and 43 fellow eyes were regarded as the contralateral group. At the same time, 21 healthy volunteers(42 eyes)matching the age and gender with RVO patients were regarded as the control group. The vessel density(VD)of inside optic disc, the whole VD of around disc and the ppVD and pRNFL thickness around the optic disc were measured by OCTA, including peripapillary superior(pS), peripapillary inferior(pI), temporal superior(TS), superior temporal(ST), superior nasal(SN), nasal superior(NS), nasal inferior(NI), inferior nasal(IN), inferior temporal(IT), and temporal inferior(TI). The characteristic changes of ppVD and pRNFL thickness and theirs correlation in the three groups were analyzed.

RESULTS: The VD of inside optic disc, the whole VD of around disc and the ppVD in the pS, pI, TI, ST and SN side of the affected group were all significantly decreased compared with the control group(all P<0.05). But only VD of the inside disc in contralateral group was decreased(all P<0.05). Compared with the control group, the pRNFL thickness in the TS side of the affected group was increased, and the ST and IT side pRNFL thickness of the contralateral group were decreased(all P<0.01). The canonical correlation analysis revealed that ppVD and pRNFL thickness were provided with a strong correlation between the two comprehensive variables. There were 2 pairs of canonical correlation variables in affected group and contralateral group, and 3 pairs of canonical correlation variables in control group.

CONCLUSION: The VD in the optic disc area of the affected group was decreased in patients with monocular RVO, and the pRNFL thickness in ST and IT side of the contralateral group was thinner. There was a strong positive correlation between ppVD and pRNFL thickness as a whole. The changes of ppVD and pRNFL thickness in the optic disc area were mostly manifested in the superior quadrant of the affected group and the inferior quadrant of the contralateral group.