Abstract
Purpose: :
To evaluate differences in the retinal blood flow velocities of patients with active uveitis and healthy controls using the Retinal Function Imager (RFI, Optical Imaging, Israel) and to determine the correlation between the retinal blood flow velocity and central macular thickness in uveitis patients.
Methods: :
16 eyes of 14 patients with active uveitis and 51 eyes of 51 normal control subjects were enrolled. Five eyes had uveitic cystoid macular edema (CME) by optical coherence tomography (SLO-OCT, OTI, Canada). Eyes with diabetic retinopathy, posterior uveitis and glaucoma were excluded. Retinal blood flow velocities by RFI and central macular thickness by SLO-OCT were obtained. Differences among the groups were assessed.
Results: :
Median (first quartile, third quartile) venous velocity for uveitic eyes with CME, uveitic eyes without CME and controls were 2.18(1.86, 2.53), 2.57(2.26, 2.91) and 2.82(2.39, 3.53) mm/s. Median (first quartile, third quartile) arterial velocity for uveitic eyes with CME, uveitic eyes without CME and controls were 3.83(3.68, 4.15), 3.42(2.99, 4.17) and 3.93(3.35, 4.65) in mm/s. Uveitic eyes with CME had significantly lower venous velocity than controls (P=0.044). There was a similar trend for uveitic eyes without CME, but it did not reach statistical significance (P=0.239). Correlation between RBF and central retinal thickness (5x5 mm grid pattern) showed a strong linear relationship between venous velocity and central retinal thickness [coefficient -0.001572 (P = 0.007)]. Arterial velocity did not correlate with central thickness [coefficient 0.000573 (P = 0.697)].
Conclusions: :
The RFI detected significantly decreased retinal venous velocities in eyes with uveitic CME relative to healthy controls, suggesting abnormal vessel function in eyes with uveitic CME. A similar trend was seen in uveitic eyes as a whole, although the difference was not statistically significant. In eyes with uveitis, a decrease in venous velocity was correlated with an increase in central retinal thickness.
Keywords: blood supply • inflammation • edema