Dye extravasation and the nature of background fluorescence in sodium fluorescein angiography.
OBJECTIVE
To obtain better insight into the process of dye extravasation in the human choroid during sodium fluorescein angiography of the ocular fundus.


METHODS
Sodium fluorescein angiography using a scanning laser ophthalmoscope was performed on the right eye of five healthy volunteers. The dose of sodium fluorescein was chosen to avoid quenching in the ocular vessels. The time-intensity curve of background fluorescence was measured and its shape compared with that of the time-intensity curve of a retinal artery, representing an intravascular compartment. Significant dye extravasation is expected to cause a marked change in shape of the time-intensity curve of background fluorescence as compared with the intravascular time-intensity curve due to long washout of dye from the interstitial space of the choroid.


RESULTS
In all five subjects, the time-intensity curve of background fluorescence and the retinal artery proved to be quite similar in shape until several seconds after peak intensity of the first bolus passage.


CONCLUSIONS
Background fluorescence originates mainly from intravascular compartments during the early phase of the sodium fluorescein angiogram.
van den Biesen
P R
PR
F.C. Donders Institute of Ophthalmology, University Hospital Utrecht, The Netherlands.
Hermens
W T
WT
Slaaf
D W
DW
D000328:Adult; D002199:Capillary Permeability; D002829:Choroid / Q000378:metabolism; D003287:Contrast Media / Q000493:pharmacokinetics*; D005119:Extravasation of Diagnostic and Therapeutic Materials / Q000378:metabolism*; D005260:Female; D019793:Fluorescein / Q000493:pharmacokinetics*; D005451:Fluorescein Angiography; D005453:Fluorescence; D005654:Fundus Oculi; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007834:Lasers; D008297:Male; D009887:Ophthalmoscopy; D012016:Reference Values; D012161:Retinal Artery / Q000502:physiology*
D003287:Contrast Media; D019793:Fluorescein