Confocal fluorescence microscopy for minimal-invasive tumor diagnosis

The goal of the project "stereotactic laser-neurosurgery" is the developmen t of a system for careful and minimal-invasive resection of brain tumors wi th ultrashort laser pulses through a thin probe. A confocal laser-scanning- microscope is integrated in the probe. In this paper, the simulation of its optical properties by a laboratory setup and the expansion by the ability for fluorescence microscopy are reported. For a valuation of the imaging pr operties, the point-spread-function in three dimensions and the axial depth -transfer-function were measured and thus, among other things, the resolvin g power and the capacity for depth discrimination were analysed. The micros cope will enable intraoperative detection of tumor cells by the method of i mmunofluorescence. As a first model of the application in the brain, cell c ultures, that fluorescein-labelled antibodies were bound to specifically, w ere used in this work. Due to the fluorescence signal, it was possible to d etect and identify clearly the areas that had been marked in this manner, p roving the suitability of the setup for minimal-invasive tumor diagnosis.