**4. Discussion**

Neurolasermicroscopy (NLM) was shown to recognize malignant brain tumor characteristics in patients with histologically proven GBM in our pilot feasibility study (Schlosser et al., 2009 (Epub)). There was a good accordance of the NLM images compared to the histopathological findings with respect to the WHO classification (Louis et al., 2007). The differentiation of more specific tumor entities by NLM should be performed after this promising technique is transferred into the intraoperative situation. Our ex vivo approach opened the door for a neurosurgical in vivo diagnosis on a cellular and subcellular level. Moreover, the combination of confocal laser microscopy and flexible video systems may promote a variety of potential developments eligible for neurosurgical procedures. This ranges from process optimization in the operating room (OR) to new ways to corroborate regenerative therapy (Wessels et al., 2007). Current research data showed the same technique we use in our pilot study to be useful in patients during neurosurgery (Sanai et al., 2011 (Epub), Schlosser, H.G., Bojarski, C. (2011 (Epub)). Confocal Neurolasermicroscopy (NLM). Neurosurgery, Epub,).
