Abstract
Purpose:
Although the choroidal blood flow (CBF) might be associated with choroidal thickness (CT), the relationship is not completely understood. Laser speckle flowgraphy (LSFG-NAVI, Softcare ltd) can evaluate relative blood velocity and volume in the choroid and optical coherence tomography (OCT) can visualize the choroid. The purpose in the current study is to evaluate CBF and CT using LSFG-NAVI and OCT.
Methods:
Fourteen eyes of seven healthy volunteers (27-41 years old, an average of 34.1 years old) were examined. Mean spherical equivalent was -4.57D, and mean axial length was 25.5mm. We measured mean blur rate (MBR) in the index of the blood flow velocity and volume, skewness in the wave of blood flow (Skew), and blowout score in the capability of blood flow (BOS) using LSFG-NAVI. We made the choroidal thickness map from 12 radial scan using swept source OCT (Topcon), and measured CT at the macular area. We also compared with each parameter in LSFG-NAVE and CT within 3mm in diameter from center of fovea.
Results:
Mean CT within 3mm was 289μm [151-488]. Mean choroid thickness within 3mm in diameter was significantly correlated with the spherical equivalence (r=0.86, p<0.01) and the axial length (r=-0.78, p<0.01). BOS showed a positive correlation with CT (r=0.69, p <0.01), and Skew also showed a negative correlation with CT (r=-0.53, p=0.02). However, MBR was not correlated with CT (r=-0.32, p=0.2).
Conclusions:
Although MBR was not correlated with CT, BOS and Skew reached significant. Thickness of the choroid might reflect not the velocity and volume of CBF but the capability of flowing through the choroidal vessels.
Keywords: 452 choroid •
585 macula/fovea •
550 imaging/image analysis: clinical