Abstract:

Objective To explore if the numbers of the hyperreflective foci (HF) is relevant to visual outcome of diabetic macular edema (DME), and to observe the changes of HF number after anti-vascular endothelial growth factor (VEGF) treatment. Design Retrospective case series. Participants We reviewed 28 eyes of 28 patients with DME, who were treated with anti-VEGF at Beijing Tongren Eye Center from February 2013 and August 2016. Methods All patients underwent best-corrected visual acuity (BCVA) measurement, slit-lamp examination, spectral domain optical coherence tomography (SD-OCT) at baseline and at final time of the follow-up. Numbers of HF were counted based on different locations including the inner retinal layer, the outer retinal layer and the vitreous cavity. Meanwhile, the areas for each vitreous cavity had to be measured. Then, the ratio of HF numbers to the total areas of vitreous cavity (RATIO) can be calculated. The correlation of the HF numbers in different locations with final BCVA was analyzed. The changes of HF number after anti-VEGF treatment were analyzed as well. Main Outcome Measures The baseline and final BCVA, central retinal thickness (CRT), the HF number in retinal layer, RATIO. Results On SD-OCT images, HF could be located in each retinal layers, as well as in vitreous cavity, but mainly located around external plexiform layer (OPL) in DME. The mean HF number in the inner retinal layer was 156.00±118.76; in the outer retinal layer it was 3.57±4.08; RATIO was 0.05±0.06. HF could be seen in the outer retinal layers among 17 eyes (62.5%), while it was visible in the inner retinal layers for all 28 eyes (100%). BCVA was negatively associated with the baseline numbers of HF in the outer retinal layers (r=-0.506, P=0.006), as well as the RATIO (r=0.462, P=0.013). However, it was not related to the baseline numbers of HF in the inner retinal layers (r=-0.163, P=0.408). The average number of HF reduced significantly in the outer and inner retinal layer, while there was not apparent change for the RATIO after anti-VEGF treatment. Conclusion HF in the outer retinal layer is obviously negatively associated with the final BCVA in patients with DME after anti-VEGF treatment. However, HF in the inner retinal layer is not associated with final BCVA.

Key words: diabetic macular edema, optical coherence tomography, hyperreflective foci, anti-VEGF