Poster (nur Text)


Intravital fluorescence microscopy has been used widely by us (Wahl M et al.: Int. J. Microcirc. Clin. Exp. 4, 3-18, 1985) and others (Mayhan WG and Heistad DD: Amer. J. Physiol. 248, H712-H718, 1985) to study blood-brain barrier (BBB) permeability. Quantification of tracer extravasation, however, is difficult because counting leaky spots provides only a semiquantitative estimation, and measuring the tracer clearance rate may involve significant error from contamination from non-cerebral vessels (e.g. dura or skull bone). We have therefore developed a new method using computerised image analysis for quantification of tracer extravasation from cerebral blood vessels in vivo.

MATERIALS AND METHODS


RESULTS I

DESCRIPTION OF IMAGE ANALYSIS PROCEDURE (FIG. 2)

Subtraction images were generated to eliminate the pattern of the pial vasculature and to correct for variations of intensity between individual fields. Generation of subtraction images required the following procedures:

Reduction of structural artefacts in the subtraction images due to dilatation or movement of pial blood vessels was achieved by the following procedures:

After performing the steps described above the mean intensity of the remaining pixels was calculated for each subtraction image to give the degree of extravasation.


RESULTS II

DETERMINATION OF THE DEGREE OF EXTRAVASATION UNDER DIFFERENT CONDITIONS

CONCLUSIONS


Zurück zum Abstract


Axel Findling, 1995-09-16
letzte Änderung: 1995-09-16