Prolonged monitoring of the blood-aqueous barrier with fluorescein- labeled albumin

Aqueous fluorophotometry has proved to be a useful indicator of changes in the blood-aqueous barrier after surgical, immunologic, or laser manipulations. Previously used fluorescent tracers have been unable to follow rapid changes continuously in the blood-aqueous barrier. Fluorescein-labeled homologous serum albumin, however, provides extremely stable and high plasma levels of fluorescence due to active renal reabsorption with very low levels in the normal aqueous because of its high molecular weight. This feature allows prolonged, continuous, and highly sensitive monitoring of the blood-aqueous barrier before, during, and after a manipulation. The usefulness of this technique is demonstrated in a model that has been well studied with other methods: the response to argon laser iris photocoagulation.