Abstract
Purpose:
To report the reproducibility of retinal blood flow measurements by using a newly developed Doppler Fourier-domain optical coherence tomography (FD-OCT) instrument in anesthetized cats.
Methods:
Four cats (2.5-5.0 kg) were anesthetized using a mixture of sevoflurane and room air. We measured retinal blood flow by using both the FD-OCT and the bidirectional LDV (Canon Laser Blood Flowmeter, Canon Co., Japan) which was customized for cats. The reproducibility of retinal blood flow measurements was assessed by calculating the coefficients of variation (CV) for repeated measurements (5X) of retinal vessel diameter, time-average centerline blood velocity, and blood flow (RBF) at temporal retinal arterioles and venules. In addition, we examined the changes in retinal blood flow in arterioles in response to systemic inhalation of 100% pure oxygen (hyperoxia) by using both instruments.
Results:
The averaged values of CV (mean ± SD) for RBF were 9.7% ± 3.8% and 8.2% ± 3.5% in arterioles and 10.3% ± 0.8% and 7.4% ± 0.9 % in venules with LDV and FD-OCT, respectively (p = 0.34 and p = 0.18). After 10 minutes of hyperoxia, RBF decreased by -43.8 ± 11.2% and -43.9 ± 7.4% with LDV and FD-OCT, respectively. There was no significant change in RBF in response to hyperoxia between LDV and FD-OCT (p = 0.87).
Conclusions:
The current study revealed that newly developed FD-OCT enable the accurate and reproducible measurements of blood velocity in retinal arterioles and venules in in vivo cats models.
Keywords: 550 imaging/image analysis: clinical •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
688 retina