A Further Comment.
—Although the argument between Dr Riva and associates and Drs Cunha-Vaz and Lima seems to center on details of methodology, it probably stems from a basic difference between these well-respected investigators in their approach to research: one side is seemingly committed to the concept that advances in basic science are dependent on the accuracy of measurements, and the other is more oriented toward obtaining clinically significant results.Generally, the criticisms by Riva and associates seem valid. In our own experience,1 first appearance time of fluorescein was found to be so dependent on background noise that we abandoned it as a reproducible measurement. This was true even if an excess of fluorescein were injected very rapidly in order to make the slope of the fluorescein intensity wave very steep and also to minimize the effect of pulsatile flow (injection within one heartbeat). Furthermore, we attempted flow measurements in retinal arteries
van Heuven WAJ. Retinal Blood Flow. Arch Ophthalmol. 1979;97(1):175. doi:10.1001/archopht.1979.01020010097029