AIM: To investigate the effect of repeated intravitreal injection of anti-vascular endothelial growth factor(VEGF)on the vitreomacular interface(VMI)and its related risk factors in patients with diabetic macular edema(DME).

METHODS: The clinical data of 31 patients(55 eyes)with DME who received intravitreal injections of Conbercept(3+PRN)in the ophthalmology department of the First People's Hospital of Zunyi from January 2018 to December 2021 were analyzed retrospectively. There were 9 cases(13 eyes)in the group that has changes in VMI and 22 cases(42 eyes)in the other group that has no changes in VMI. The best corrected visual acuity(BCVA), central retinal thickness(CRT), and central choroidal thickness(CCT)of the two groups were compared, and the risk factors of VMI change were analyzed.

RESULTS: The patients were followed up for an average of 9.58±8.32mo, received an average of 4.07±2.17 times of anti-VEGF therapy, and the number of intravitreal injections in VMI changed group was more than that in VMI unchanged group(5.77±2.09 times vs. 3.55±1.93 times, P=0.001). At the last follow-up, compared with before treatment, the BCVA of both patients improved significantly after treatment(both P<0.05), while CCT had no significant change(both P>0.05). CRT of patients in the VMI unchanged group decreased significantly(P=0.039), but there was no significant change in patients of VMI changed group(P=0.627). Logistic regression analysis showed that BCVA was a risk factor for VMI change before treatment(P=0.049, OR=6.210, 95%CI 1.006～38.346).

CONCLUSIONS: The VMI of DME patients may change during repeated intravitreal injections of anti-VEGF drugs. The worse the BCVA before treatment, the higher the risk of change in VMI, and the patients with VMI change have a poor response to anti-VEGF treatment.