Association of macular perfusion status with microvascular parameters up to the far periphery in diabetic retinopathy using multimodal imaging

Abstract

Background The aim of our study was to investigate a possible association between macular perfusion status and retinal ischemia and leakage up to far peripheral retinal areas in eyes with early to advanced stages of diabetic retinopathy (DR). Methods In a retrospective, cross sectional analysis ultrawide field (UWF) color fundus photos (Optos, Optomap California) were graded for DR severity. Foveal avascular zone (FAZ) and vessel density from the superficial (SCP) and deep capillary plexus (DCP) were assessed on optical coherence tomography angiography (OCTA) scans (Topcon, DRI-OCT Triton). UWF angiography images were used to quantify leakage/ischemic index and number of microaneurysms (MA). Age, gender, disease duration, type of diabetes, HbA1C, hypertension, complications of diabetes and ocular history were recorded. Univariate mixed models and Spearman correlation analysis were used for statistical testing. Results 24 eyes of 17 laser-naive diabetic patients with different stages of DR were analyzed. The mean age was 59.56 ± 8.46 years and the mean disease duration 19.65 ± 12.25 years. No statistically significant associations between FAZ size, macular vessel density of SCP/DCP and peripheral retinal ischemia, leakage and MA number were demonstrated. Higher stages of DR were associated with ischemic index (estimate [95% CI]: 13.04 [1.5; 24.5], p = 0.033) and MA count (estimate [95% CI]: 43.7 [15.6; 71.8], p = 0.01), but no association with leakage index was observed. Only weak correlations between DR severity and anamnestic data were found. Conclusion Retinal ischemic index and the amount of MAs assessed on UWFA up to peripheral areas are indicators of DR severity but not related to microvascular perfusion status in the macular region. Significance and timely sequence of macular vessel density in DR progression may need to be re-evaluated in future studies.

Intraprocedural OCT monitoring of the immediate treatment response during indocyanine green angiography-guided laser therapy of teleangiectatic capillaries in diabetic macular edema

“…Ultra-widefield imaging, another innovation in retinal imaging, allows for a standardized evaluation of diabetic retinal changes up until the far periphery 32 , 33 . While resolution of ultra-widefield imaging devices is useful to detect peripheral ischemia and neovascularization and still might be sufficient to depict TCs, we know from clinical experience, that small retinal vessels in the macular region are commonly not well visualized.…”

Featureless retina in diabetic retinopathy: Clinical and fluorescein angiographic profile

“…There is a dichotomy in literature in this regard: UWF-FA reportedly revealed a significant association of macular ischemia with peripheral ischemia[ 13 ]; but a more recent report employing both UWF-FA and noninvasive swept-source OCT angiography (UWF SS-OCTA) showed no such association, like us. [ 14 ] Indeed, the gold standard ETDRS grading system is probably due for an update,[ 15 ] both due to the frequency of DR changes outside the posterior 30-degree fields and because the clinically observed changes do not always follow a set temporal sequence, as we also observed in our case series.…”

“…[ 2 ] We found a high percentage of DMI in this study, in line with the predominance of advanced DR as revealed by FA; DMI was significantly associated with poor vision, as shown by others. [ 10 13 14 ] However, we did not find a significant association between macular and midperipheral ischemia, probably because we used conventional FA and not ultra-widefield imaging (UWF-FA), limiting our assessment of peripheral CNP. There is a dichotomy in literature in this regard: UWF-FA reportedly revealed a significant association of macular ischemia with peripheral ischemia[ 13 ]; but a more recent report employing both UWF-FA and noninvasive swept-source OCT angiography (UWF SS-OCTA) showed no such association, like us.…”

Relationship Between Nonperfusion Area from Widefield Optical Coherence Tomography Angiography and Macular Vascular Parameters in Diabetic Retinopathy

“…In this study, we evaluated the relationship between the NPA from wide eld OCTA and macular vascular changes in DR. A similar study was performed in the past, but Hajdu et al assessed peripheral ischemia using ultrawide eld angiography [11]. They revealed no association between the leakage index and VD of the SCP and DCP.…”