Abstract: Objective　To investigate the value of optical coherence tomography angiography (OCTA) and multispectral fundus imaging system (MSI) in the screening of nonproliferative diabetic retinopathy (NPDR). Methods　A total of 118 eyes of 59 patients with type 2 diabetes mellitus and NPDR were observed and studied. All the patients underwent fundus fluorescein angiography (FFA), multispectral retinal imaging (MSI) and OCTA examination. The imaging features of four kinds of fundus lesions including microaneurysm, rigid exudation, velvety spot and hemorrhage in FFA, OCTA and MSI images of diabetic retinopathy (DR) affected eyes were recorded. The consistency of OCTA and MSI noninvasive examination and FFA in the above fundus changes was analyzed. Results　OCTA, MSI and FFA showed good consistency in detecting retinal microaneurysms in NPDR patients (Kappa: 0.783 and 0.815); OCTA and MSI sensitivity were 98.02% and 99.01%, specificity were both 76.47%, Youden index were 74.49% and 75.48%. OCTA and MSI showed good consistency in the detection of retinal hard exudation (Kappa: 0.836 and 0.891); OCTA and MSI sensitivity were 94.59% and 95.95%, specificity were 88.64% and 93.81%, Youden index were 83.23% and 89.13%. For cotton wool spots detection, OCTA and FFA showed poor consistency, and MSI and FFA showed general consistency (Kappa: 0.192 and 0.467). OCTA and MSI sensitivity were 75.00% and 83.33%, specificity were 66.98% and 87.50%, Youden index were 41.98% and 70.83%. OCTA and FFA were generally consistent in retinal hemorrhage, while OCTA and MSI showed good consistency (Kappa: 0.684 and 0.906); OCTA and MSI sensitivity were 93.41% and 96.70%, specificity were 74.07% and 96.30%, Yoden index were 67.48% and 93.00%. Conclusion　OCTA and MSI have high clinical value in the diagnosis of microaneurysms and rigid exudates in NPDR eyes. MSI is more advantageous than OCTA in the diagnosis of retinal hemorrhage. However, OCTA and MSI should be cautious in the diagnosis of cotton wool spots.

Key words: diabetic retinopathy, diabetes mellitus, type 2, fluorescein angiography;tomography, optical coherence, multi spectral fundus imaging system, optical coherence tomography angiography, fundus fluorescein angiography