The technique of reflective densitometry was brought to a high level of technical development by Rushton et al1 at Cambridge for their studies of the visual pigments. This paper shows how the technique may be used to measure the blood volume and blood flow rate in the living eye. In 1961 Broadfoot et al2 applied this method to a qualitative study of choroidal blood volume changes. They demonstrated its feasibility in an elegant series of experiments. They did not, however, discuss the quantitative aspects of the technique.
Reflective densitometry has been used quantitatively to determine the amounts of photopigment in the albino rabbit eye. Hagins3 has made unpublished experiments which have extended this technique to estimate ocular blood flow. Applying these methods, the experiments reported here were performed and the volume and flow rate of blood in the ocular fundus of ten albino rabbits have been determined.
STEPHEN TROKEL. Measurement of Ocular Blood Flow and Volume by Reflective Densitometry. Arch Ophthalmol. 1964;71(1):88–92. doi:10.1001/archopht.1964.00970010104017