Mapping the human blood-retinal barrier function.

The aim of the work herein presented is to map blood-retinal barrier function by measuring retinal fluorescein leakage from the blood stream into the human vitreous using a confocal scanning laser ophthalmoscope (CSLO). Existing methods for the assessment of fluorescein leakage into the human vitreous are based on the qualitative evaluation of fluorescein angiographies (FA) and on volume measurements, as performed by the Fluorotron Master. A new procedure is presented capable of measuring fluorescein leakage into the vitreous while simultaneously imaging the retina. The present methodology computes the fluorescein leakage in a fully automated way, based on the three-dimensional fluorescence distribution in the human eye by using a single data acquisition. The processing includes signal filtering, volume alignment and profile deconvolution. The deconvolved profile obeys the established physical model. Representative cases shown are: a healthy eye; an eye with drusen from a nondiabetic person; a photocoagulated eye; and an eye with nonproliferative diabetic retinopathy. The results are in agreement with previous findings and go a step further by making possible its daily usage in a clinical setup based on currently available instrumentation.