Molecular size of retinal vascular leakage determined by FITC-dextran angiography in patients with posterior uveitis.
In order to investigate the selective breakdown of the blood-retinal barrier in posterior uveitis angiograms were performed using fluorescein-conjugated dextrans (FITC-dextrans) of different molecular weights (150-kDa, 20-kDa, and 4-kDa) in two healthy controls and six patients with posterior uveitis, and the results compared with those of conventional fluorescein angiography. The smallest FITC-dextran could not penetrate the healthy blood-retinal barrier. Leakage of FITC-dextrans of all sizes was seen from swollen optic discs; dextrans of 4-kDa and 20-kDa leaked from areas of macula oedema; and retinal new vessels allowed the passage of 4-kDa molecules only. These results indicate that there is a differential breakdown of the blood-retinal barrier according to molecular size in various clinical situations associated with posterior uveitis.
Atkinson
E G
EG
Department of Immunology, United Medical School, London.
Jones
S
S
Ellis
B A
BA
Dumonde
D C
DC
Graham
E
E
D000328:Adult; D001813:Blood-Retinal Barrier / Q000502:physiology*; D003911:Dextrans / Q000493:pharmacokinetics; D005260:Female; D005451:Fluorescein Angiography; D016650:Fluorescein-5-isothiocyanate / Q000493:pharmacokinetics / Q000031:analogs & derivatives; D006801:Humans; D008268:Macular Degeneration / Q000473:pathology; D008297:Male; D008970:Molecular Weight; D009898:Optic Disk / Q000473:pathology; D012171:Retinal Vessels / Q000473:pathology*; D015866:Uveitis, Posterior / Q000473:pathology*
D003911:Dextrans; C015219:fluorescein isothiocyanate dextran; D016650:Fluorescein-5-isothiocyanate