Significant Correlation Between Retinal Blood Flow and Oxygen Saturation During Intravitreal Aflibercept Treatment for Central Retinal Vein Occlusion.

PURPOSE

The purpose of this study was to evaluate the relationship between retinal blood flow and oxygen saturation during intravitreal aflibercept treatment for central retinal vein occlusion (CRVO) using OxymapT1 and laser speckle flowgraphy (LSFG).

METHODS

Thirty-two untreated patients (32 eyes) with nonischemic CRVO received monthly intravitreal aflibercept injections for 3 months followed by a pro re nata regimen; they were followed up for approximately 1 year. Central retinal thickness, retinal oxygen saturation, and retinal blood flow were measured using optical coherence tomography, OxymapT1, and LSFG, respectively.

RESULTS

Visual acuity (VA) and central retinal thickness (CRT; µm) significantly improved from 1 month onward in both the all-patient and nonischemic groups (VA baseline = 0.51, 0.48, 1 month = 0.30, 0.29, P = 0.049, P = 0.032; and CRT baseline = 615.0, 615.0, 1 month = 278.4, 275.0, P = 0.049, P < 0.001). Using OxymapT1, retinal venous oxygen saturation was reduced at baseline but significantly increased from 1 month after aflibercept injection and remained elevated in both groups (baseline = 34.1%, and 1 month = 41.1%, P = 0.006). Mean blur rate (MBR) remained stable overall, with a significant increase at the final visit in the nonischemic group (baseline = 22.4, and final = 27.4, P = 0.001). A significant positive correlation was found between venous oxygen saturation and MBR from 1 month after treatment onward (1 month = R = 0.538, P = 0.002).

CONCLUSIONS

In CRVO, venous oxygen saturation and MBR were significantly correlated.

TRANSLATIONAL RELEVANCE

Measuring and evaluating retinal blood flow and oxygen saturation during treatment of CRVO eyes is recommended.