Abstract
Purpose::
The Retinal Function Imager (RFI, Optical Imaging, Ltd.) is a non-invasive instrument capable of quantifying blood flow velocity in small retinal vessels. This study sought to determine the precision of those measurements in vitro using an "artificial eye", as well as with in vivo measurements.
Methods::
The in vitro model included a mechanical system that simulates the optical geometry of the eye and blood flowing through a retinal vessel. A high precision syringe pump, moved blood through the model system at various flow rates while images were captured with the RFI. In vivo measurements were made on tissues including the retina.
Results::
The in vitro results showed a strong correlation (R2 > 0.99) between the actual and the measured retinal blood flow velocity. Larger variability was observed at model retinal vessels with a diameter larger than 20µ. That suggests that the RFI is capable of providing reproducible measurements of retinal blood flow velocity in small retinal vessels, including capillaries.
Conclusions::
The results suggest that the RFI is capable of providing acute measurements of retinal blood flow velocity in small vessels.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • retina