Wide-field en face swept-source optical coherence tomography angiography using extended field imaging in diabetic retinopathy

Aims To examine the feasibility of wide-field en face swept-source optical coherence tomography angiography (SS-OCTA) with extended field imaging (EFI) for evaluation of the retinal vasculature in diabetic retinopathy (DR). Methods This study included 37 eyes of 27 patients (age, 65 +/- 10 years; male patients, 18; female patients, 9) with DR. All patients underwent comprehensive ophthalmological examination, including OCTA and fluorescein angiography (FA). The imaging methods were compared for visible field of view, presence and extent of non-perfused areas (NPAs), presence and number of new blood vessels (NVs), vessel density (VD) and patient comfort level measured by Visual Analogue Scale. Results SS-OCTA with EFI allowed capture of larger areas (by 1.80 +/- 0.18 times on average) of the fundus than SS-OCTA without EFI. Compared with FA, the sensitivities of SS-OCTA with EFI for detection of NPAs and NVs were 96% and 79%, respectively, with specificities of 100% and 96%, respectively. There was no significant difference in extent of NPAs (61.2 +/- 45.8 vs 61.5 +/- 55.0 disc areas, P=0.99) or number of NVs (1.5 +/- 3.3 vs 0.9 +/- 1.8, P=0.68) between FA and SSOCTA with EFI. VD showed significantly lower values in EFI SS-OCTA than in those acquired without EFI (31.6%+/- 4.3% vs 34.2%+/- 4.3%, P<0.001). Wide-field OCTA with EFI was significantly more comfortable for patients than FA (P<0.001). Conclusions SS-OCTA with EFI allows acquisition of wide-field en face images of the retinal vasculature in patients with DR, with greater patient comfort than FA.